14...Laurie Whitaker from Shropshire, with an illustrated account of a trip to Clee Hill with the Shropshire Geological Society, while the 12-16 prize went to “The Palaeontology

MERCIAN GEOLOGIST 1999 14 (4)

Journal of the East MidlandsGeological Society

President Vice-PresidentDr. R. J. O. Hamblin Mrs. S. M. Miles

Secretary TreasurerMr. A. J. Filmer Mrs. C. Moore

Editorial BoardDr. J. N. Carney Mrs. J. B. RigbyDr. A. S. Howard Mrs. J. M. SmallMr. T. Morris Dr. A. C. Waltham

CouncilMrs. J. Anderson Mr. L. R. HallMr. J. Aram Mrs. P. M. JonesMr. C. Bagshaw Dr. P. G. SmallMr. B. Bentley Dr. I. D. SuttonDr. P. Gutteridge Mr. D. Usher

Address for CorrespondenceGeneral information and membership details:The Secretary, E.M.G.S.Rose Cottage, Chapel Lane,Epperstone, Nottingham NG14 6AETel: 01159 663854

The Mercian Geologist is published by the EastMidlands Geological Society and printed byNorman Printing Ltd, Nottingham and London.Paper made from woodpulp harvested fromrenewable forests, where replacement rate exceedsconsumption.

No part of this publication may be reproduced inany other publication without the prior writtenconsent of the Society.

Registered Charity No. 503617

© 1999 East Midlands Geological SocietyISSN 0025 990X

Contents

Mercian News 154Bakewell Bargains; The Flying Finns; Rockwatch1999; Sculptured Stones; Trent Trends

Reports 156Cool Peterborough exhibition — A. Dawn andA. FilmerPeak District Mining Museum — L. Willies

T. D. Ford 161The Growth of Geological Knowledge in thePeak District

M. Evans 191A new reconstruction of the skull of the Callovianelasmosaurid plesiosaur Muraenosaurus leedsiiSeeley

H. E. Boynton 197New fossils in the Precambrian of CharnwoodForest, Leicestershire, England

Excursion Reports 201P. Gutteridge — Wye ValleyK. Ambrose and A. Filmer — Cloud Hill QuarryJ. Small — Field excursion to Skipton MoorK. Ambrose — Ticknall and Ibstock Brick PitT. Morris — Field visit to the Malverns Area

Secretary’s Report 213A. J. Filmer — Report for 1998/99

Book Reviews 214

Index Volume 14 216

VOLUME 14 PART 4 DECEMBER 1999

the first project under a recently agreedMemorandum of Understanding between theBritish Geological Survey (BGS) and the GeologicalSurvey of Finland (GTK). The work was co-sponsored by the Department of the Environment,Transport and the Regions and the EnvironmentAgency.

The survey was flown using the elegant andpowerful de Havilland Twin Otter based atTollerton Airport near Nottingham. The mainobjective of this trial was to test the effectiveness ofthe GTK electromagnetic (EM) system in the rapidmapping of polluted groundwaters that may occur inthe vicinity of certain landfill sites and colliery spoilheaps. GTK have proved the value of their system insuch applications in Finland and BGS decided totest the method in the generally less favourable UKenvironment. In addition to EM, gammaspectrometer and magnetic total field and horizontalgradient data were also collected. These additionaldata will also be of both geological andenvironmental significance.

The four areas targeted are Shirebrook, the TrentValley immediately north east of Nottingham,Langar-cum-Barnstone (all in Nottinghamshire)and Wolvey near Rugby. The preliminary results arevery encouraging and several of the features detectedwill be investigated by ground survey in the nearfuture. The fully processed data will be available forlicencing in due course.

Rockwatch 1999 — RockhoundChallenge winnersJohn Aram writes: The 1999 Rockwatch competitionresults have just been announced, and once againentries from local children featured strongly in thefinal stages of the judging.

Katy Flinn from Nottingham received a specialprize in the 12-16 Rock Artist competition for herbeautiful hand-made book of illustrations ofgeological specimens; the first prize going to StefGladders of York for an original 3-D cave model.

Emily Ratcliffe of Sleaford created a rotundpapier-maché woolly mammoth that earned her aHighly Commended in the very competitive under12 years class of the same section of the competition.The winner was an impressive collage made byThomas Baird from Northern Ireland.

The Rock Reporter under 12 class was won byLaurie Whitaker from Shropshire, with an illustratedaccount of a trip to Clee Hill with the ShropshireGeological Society, while the 12-16 prize went to“The Palaeontology Post”, a newspaper written andproduced by Kathy Marshall of Leeds.

Jane Robb won the under 12 Rockhound prizewith a folder describing and illustrating hergeological collection and the mini-museum in herhome in East Lothian. Winner of the 12-16competition and ‘Rockhound of the Year 1999’ was12 year old Alex Ayling of Sandhurst, for an

MERCIAN NEWS

154 MERCIAN GEOLOGIST 1999 14 (4)

M E R C I A N N E W S

Bakewell for Bargains!John Aram writes: The 9th and 10th October 1999found the largest gathering in the region ofgeological dealers, suppliers, collectors, academicsand amateur enthusiasts for ‘The Rock Exchange’.

Under the control of the Peak Lapidary andMineral Society and the guidance of Les Fox, thisannual event takes place in the Lady MannersSchool near Bakewell. For two days the schoolSports Hall, Drama Hall, canteen area and even thecorridors are taken over by dozens of displays andstands, selling and demonstrating everything andanything related to geology. Free parking is providedin staff and coach parking areas, with the overflowonto mown grass and an adjacent sports field.

This year my eye was caught by machines to crackopen geodes, hands-on demonstrations of goldpanning, and guidance in polishing rock slices.Magnetite crystals from Shetland vied for myattention with haematite from Cumbria and fluoritefrom the Pennines. Increasingly rare trilobites inmudstones from North Wales contrasted with largenumbers of finely detailed and prepared trilobitesfrom North Africa. Bargain bins, oddments andspecial show prices contrasted with a gem-qualitysapphire in its matrix with a four figure price tag. Nodoubt the many specialist dealers and part-timecollector/dealers who are attracted to this show fromall parts of Britain help to create a wide range ofprices and quality of specimens.

The bargains? One member of EMGS went homethe proud owner of a ‘nearly new’ lap for polishinghis rock specimens (bought at a fraction of its ‘new’cost). A Rockwatch member came from Coventry tospend his pocket-money on trilobites; when he lefthe not only had five new specimens to add to hiscollection, but had also been given a large bag of‘interesting pieces’ of trilobites by one of the stall-holders. Myself? In addition to the new milleniumsupply of white card trays to store specimens, andthe ‘write-on’ plastic self-seal bags (I have promisedto maintain much better records of my specimens),a small, battery-powered ultra-violet lamp has beenadded to my equipment, and a splendid newspecimen of green fluorite from Wearsdale can nowbeen seen in my cabinet. They were all bargains!

Put next year’s show dates (7th and 8th October,2000) into your diary. But take a warning; allowyourself plenty of time (and money) for your visit.Selecting a bargain can take time, and there are somany choices to make.

The Flying Finns . . .Roger Peart (BGS) writes: Late June 1999 saw thecompletion of data acquisition for a collaborativeairborne geophysical and environmental trial surveyof four sites in the East Midlands. This was part of

outstanding report of his collecting work, laboratorypreparation and study of micro-fossils.

If you know of any keen young geologists, do tellthem to watch out for details of the 2000Rockhound Challenge. The prizes in each class areworth up to £100 worth of geological materials,specimens, equipment and books!

Sculptured Stones at Rufford CountryParkAlan Filmer writes: Fashion in gardening hascurrently moved to hard landscaping, with plantssometimes playing merely a supporting role. In thisgarden, created by Gerry Price, this idea has beentaken to its ultimate conclusion with scarcely a plantin view. However, for a geologist with an interest ingarden design and sculpture, it is full of interest. Thegarden was created in June 1999 and will beremoved in June 2000. It is laid out like aconventional garden with curved island beds butplanted with rocks and stones and having mulches ofdifferent coloured, textured and sized pebbles orchippings. Among these there are a number ofsculptures carved from various types of stone and indiffering stages of completion.

The garden provides an interesting geological trailin a compact area, with plenty of scope for trying toidentify the rock types and processes that are inevidence. Rufford Country Park is on the A614between Nottingham and Ollerton. Entrance is freewith a parking charge only at weekends and BankHolidays. To find the garden, park in the main carpark and walk through the old stable block andcourtyard. Enter the sculpture gardens and turn left.

Trent Trends, Nottingham University,16th October 1999Phillip and Judy Small write: This conference washeld in the Djanogly Arts Centre, NottinghamUniversity, and was organised by the Trend andPeak Archaeological Unit and C.B.A. EastMidlands. A series of excellent speakers reviewedthe discoveries and developments in archaeology inthe Trent valley over the last 45 years and discussedthe new techniques that were being applied.

Several members of the EMGS were present andwere pleased to find how the geology of the Trentvalley had played such a major part in thedevelopment of early civilisation. Identification ofsites may involve both aerial and geophysicaltechniques. Scientific backup for archaeology nowinvolves the talents of many other experts.

The Trent, the third longest river in England, isfed by the Dove and Derwent, which both rise in thePeak District. In early post-Devensian times,enormous quantities of gravel were brought down bymeltwaters into the braided river systems of the wideTrent valley. As the river meandered across thevalley floor, palaeochannels were left behind which

are now frequently exposed as the gravel isextracted. This has led to the discovery of manyimportant artefacts such as bridges, fish weirs andthe Bronze Age Aston log boat. The gravelexcavations need continuous pumping. Artefactsand wooden structures have often been wellpreserved by the high water table but need urgentattention when exposed to air and sunlight. Sandsand well-preserved organic-rich mud deposits areoften related to the palaeochannels and these maycontain plant and animal parts which can beidentified by experts. Beetle wing cases are oftenwell preserved and give good information about theenvironment in which they lived. Plant material isalso of value. Oak tree trunks are of particularimportance as dendrochronology can often give areliable date for worked wood and associatedartefacts.

There are only a few professional archaeologistsworking in the Trent valley and much valuable helpis provided by enthusiastic amateurs. Dr ChrisSalisbury, who is also a keen EMGS member, hasspent much of this spare time studying the Trentvalley. For many years he has been regularly visitingmany of the gravel pits and has a good rapport withthe quarry staff. He is often contacted whensomething interesting has turned up. His majorcontributions to local archaeology were freelyacknowledged by many of the speakers.

News items for the MercianTo mark progress into the new millennium, theEMGS editorial board aims to expand the newssections of the Mercian Geologist in order to reflectthe many aspects of local geology with which Societymembers are involved. Future issues will featuremore short items, on, for example, significanttemporary exposures, geological events, importantsites within the East Midlands and small items oflocal research, beside devoting pages to thepublication of longer papers. We will thereforewelcome any text (with or without illustrations) thatis sent in by members.Please send any material to the new editor, TonyWaltham (see notes for contributors at the end ofthis issue). A single copy is all that is needed, and thestyle can be very informal; just call the editor if youhave concerns about any drawings or photographs.Don’t hold back or delay with your contributions,especially in the spring months when issues areprepared for printing. We hope that this way forwardwill make the Mercian an active record and forum ofits members, in a style that befits an active localsociety.

MERCIAN NEWS

MERCIAN GEOLOGIST 1999 14 (4) 155

The Museum has a considerable collection of allthese remains. To them were added, during thecourse of preparation, half the pelvic girdle of amammoth, and part of the vertebral column of ahorse. New finds are made regularly.

The elephant bones were prepared with the adviceof Dr Tony Stuart, of Norwich Castle Museum, whosupervised the excavation of the West Runtonelephant, and of Nigel Lark, who is conserving andreplicating the West Runton specimen. It wasdecided to display not only the bones of thesecreatures but also to illustrate their environmentswith large scale paintings and to show their actualsize by means of life-size cardboard cut-outs. Theelephant had to be scaled down a little to fit into thegallery, but bison, horse, rhino, hyena, auroch,reindeer and fallow deer were all true to size. Exceptfor the elephant, which was cut out in hardboard, allthe rest were constructed from glued-up cardboardboxes and scrap materials, costing nothing exceptfor the paint and glue.

Explanatory texts were prepared and the wholeshow came together by May 1999. Dr Adrian Listerof University College London performed theopening ceremony before an invited audience ofabout 130 people. The exhibition ran until the endof November 1999 and proved highly popular,attracting many hundreds of visitors throughout thesummer. The entire project was carried out byvoluntary work, mainly by members of Stamfordand District Geological Society.

The exhibition was supported by generous grantsfrom the following: Lafarge Redland; the COPUSfund; The Earl FitzWilliam Charitable Trust;Stamford Geological Society; Friends ofPeterborough Museum and Art Gallery; AnglianWater; Pedigree Petfoods and the StamfordMercury, plus many individual subscribers. TheEast Midlands Geological Society contributed £500towards the cost of casting the elephant skeleton.

A booklet entitled “Cool Peterborough” wasprepared to accompany the exhibition, but alsostands alone as an excellent introduction to theQuaternary history of the region. It describes howthe environments, flora and fauna of thePeterborough area have changed during theQuaternary, commencing with IpswichianInterglacial and continuing through the LateDevensian glaciation to the present day. It is wellillustrated with maps, stratigraphic sections andprofiles through the Quaternary deposits, andincludes some of Alan Dawn’s superb handdrawings of elephants, rhinoceros and aurochs.

Printing was sponsored by Kall-Kwik Print CopyDesign of Peterborough. The booklet is availablefrom the City Museum and Art Gallery, Priestgate,Peterborough PE1 1LF, price £2.50, plus postageand packing. Proceeds from the sale go towardscasting of the exhibits for permanent display.

Compiled by the Editor from contributions by Alan Dawnand Alan Filmer

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R E P O R T

Cool Peterborough —An Ice Age spectacularThis exhibition about ice-ages at PeterboroughMuseum and Art Gallery was inspired by thediscovery in 1996 of a considerable part of theskeleton of the straight-tusked elephantPalaeoloxodon antiquus. The bones were found in asand and gravel quarry operated by Lafarge Redlandat Deeping St. James. The quarry normally exploitsthe Late Devensian (cold stage) gravels of theWelland valley. The skeleton was preserved,however, in the silts and clays of an abandoned riverchannel within much older (warm stage) Ipswichiangravels underlying the Devensian deposits. Thesands deposited by this ancient ‘proto Welland’ riverhave been dated as 117,000 years BP by thermo-luminescence techniques. The present-day riverWelland flows within a hundred metres of the site.

The exciting find of the elephant was well worth itsown exhibition at Peterborough Museum, andpreparations were put in hand. As time progressed,the plans grew to encompass a more wide-rangingdisplay of all the animals whose remains have beenfound in the gravels, and the ice age exhibition tookshape. It comprised three stages:1. The Ipswichian warm period which contained

the elephant, together with hippopotamus,beaver, fallow deer and brown bear;

2. The Late Devensian, with mammoth, horse,bison, reindeer, woolly rhinoceros;

3. The early post-glacial (Holocene) period, fromwhich a near-complete skeleton of Bos primigenius(wild ox, or auroch) had been discovered in theNordolph peats, at Whittlesey, at about the sametime as the elephant was found.

Palaeoloxodon antiquus from the painting by Alan Dawn.

in total, with production now confined to by-product lead. The only lead now smelted in thePeak, however, comes from secondary sources,mainly batteries.

The oldest artefacts include a ceremonial lead axefrom Middle Bronze Age times which was found atthe hillfort on Mam Tor at Castleton and, about tocome to the Museum, a bone tool from Ecton,recently radiocarbon dated at 3800-3600 years BP.The earliest major artefacts are a substantial numberof lead ingots from the Roman period, though nocertain mines have yet been located. About thirtyingots or pigs have been found on land, inscribedwith “LVT” the mark for Lutudarum, reasonablyestablished as the settlement now under CarsingtonWater near Wirksworth. But over 200 more ingots,some at least from Derbyshire, have been found in aRoman wreck off Ploumenac in Normandy — onemarked ICENI, the tribe whose western border wasprobably the Trent. This river has always, with theIdle and Don, been an outlet for Derbyshire lead.Visitors to Nottingham’s Brewery Yard can see alarge pig of lead recovered from gravels nearColwick, marked with the monogram LW. Thewriter sees this as a particularly good omen! TheMuseum has about half a dozen lead ingots in itscollection.

Until its poisonous properties outweighed itsutility, Lead the Precious Metal (the title of a bookpublished as recently as 1924*) was the equivalentof modern plastic. In a large house, such as Bess ofHardwick’s late 16th century Hall (built with moneyearned by three deceased husbands from lead, iron,coal and land) the metal and its compounds wereused lavishly. Her stone initials on the roof line wereanchored in lead and the roof, gutters anddownpipes were of the metal. The windows“Hardwick Hall, all glass no wall” were, of coursefitted in lead cames. Water was kept in cisterns oflead, delivered in pipes of lead and sprayed infountains from ornamental (lead) figures. Inside thehouse the tables and sinks were sometimes leadcovered, and lead with tin was used as pewter orwith tin and silver as a solder. Expensive tea andother spices arrived in lead-lined boxes and tobaccowas traditionally kept in its lead jar. White, orange orred lead (oxycarbonate and oxides of leadrespectively) would have been used in paints or as abase of other colours. Red lead was a majorcomponent of lead crystal glass too. White lead hadeven greater utility — perhaps as the glaze forWedgwood’s creamy Devonshire Ware, or for aperfect white face foundation powder, with linseedoil to waterproof the canvas roof of carriages, forenamelled trinkets, even as a poultice for a bruisedthumbnail. It might also have been used forwhitening bread (a well-located cornmill was said tobe next to either a chalk pit or a paupers’ grave yardand a white lead works!). Other salts such as thesoluble acetate “sugar of lead” were useful forsweetening wine and for treating unfortunateailments such as syphylis. And, for the sporting

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R E P O R T

Peak District Mining MuseumMatlock Bath, DerbyshireThis summer (1999) Peak District Mining Museumis 21 years old. Planned, constructed and operated bymembers of Peak District Mines Historical Society,it had taken a year for the first stage to be ready foropening and is still steadily developing. The projectwas initially sparked by the need to remove and thendisplay the 1819 Wills Founder water-pressurepumping engine. This was half-buried in silt some360 feet underground in the Winster mine, in achamber which was normally flooded and likely tobe lost for ever. Originally it was part of an attemptin the 1840s to sink below the toadstone, a volcanicbasaltic lava, to the unknown and, thus,undoubtedly fabulously rich deposits below. Thiswas not to be, but now the thirty feet high engine sitsin a dry shaft right at the centre of the Museum.

Out of some twenty seven or so rocks and mineralswhich have been mined in the Peak, until iron andcoal supplanted it, lead was for some 3500 years themost important. The main ore is galena whichoccurs in rakes (mineralised wrench faults), pipes(infilled or metasomatised stratiform deposits) andin widened joints known to “t’oad man” as scrins. Arich deposit of copper ore was mined at Ecton andnearby on the Derbyshire/Staffordshire border.Several minor minerals were often mined also, suchas haematite and limonite, zinc blende and calamineand, mainly this century, the former waste or gangueminerals fluorite, barite and calcite have beenworked on a considerable scale. Only one under-ground mine, Milldam at Hucklow, is still active forvein minerals, though another, at Middleton-by-Wirksworth, mines high grade limestone on aconsiderable scale.

For two centuries Derbyshire was the economiccentre of the world lead industry. After theDissolution of the Monastries in the 16th Centurythe availability of vast amounts of church roof-leadruined the European lead industry and, out of theashes, rose the Derbyshire industry. New smeltingtechnologies made huge amounts of earlier waste-ore available from old hillocks: in the mid 17thcentury perhaps 40,000 people were dependent inthe Peak on lead’s prosperity. New skills in drivingsoughs or drainage tunnels in hard rock — includingvery early use of black-powder (i.e. gunpowder) —and then the development of steam power madehuge quantities of lead ore available. About 1730 forexample, Yatestoop mine in Winster probably hadthe World’s greatest concentration of steam power,with three certainly and, possibly, four Newcomenengines installed (though the total power wasprobably hardly more than a family car can producetoday). Fifty years later saw the beginning of a longdecline which lasted until Mill Close Mine, Britain’slargest ever lead mine, closed in 1939. Probablysome two million tons of lead ore have been mined

REPORT


Fig. 1. The Wills Founder pumping engine at its original site deep in the Winster mind. The mine chamber is normally flooded,and the pumping engine is now in the Museum at Matlock.

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Fig. 2. Pushing an ore tub through the Temple Mine at Matlock; this section of tunnel was driven in the dolomitised MatlockLimestone.

weekend, or for use of the regiment in times of war,lead was irreplaceable for shot and bullets. And atthe end of a lead-shortened life, a lead-lined coffin.

The effect on the landscape was great too. Therakes and scrins still dominate wide areas oflandscape in and alongside the Derwent Valleybetween Wirksworth and Castleton — there areespecially good examples on High Tor at MatlockBath. The mining villages and towns, mostly indecline until recent commuting habits reversed thetrend, form some of the most unspoiled in the Peak:Wirksworth where the lead mining Barmoot Courtstill sits; Bonsall; Winster (Derbyshire’s third largestsettlement at its peak around 1750); Youlgreave(from Auldgrove or Old Mine); Ashford; Eyam andBradwell. On the streams and rivers are the remainsof leats and weirs of the smelting mills, the main userof water power until the usurper, cotton, tookadvantage of the decline. And in the soil, levels oflead contamination on old mine and smelting sitesare high enough nowadays almost to be thought ofas ore.

So the museum is about lead and lead mineraldeposits, about the countryside around, aboutpeople and their houses and how they won the metalfrom the earth. At present we are developing ourdisplays to tell something of the history of geologyand how mineralisation occurs, including a recentlyinstalled display of one of the country’s finestcollections of minerals, that of Professor Howie ofDeere, Howie and Zussman book-fame. ProfessorHowie liked our displays and felt a small museumwould cherish his collection more than a larger:there are now about 200 of the most mouth-watering items on display, including the eponymousHowieite. Over the road, visits can be made to ourlead and fluorite mine, with one of the bestexposures of basaltic lava (toadstone) visible — thesite of the only authenticated gold discovery in theCounty. The Museum is open every day (Telephone01629 584322). For visiting groups the Society’sfield centre at Magpie Mine, Sheldon near Bakewell,has basic hostel accommodation.* Harn, Orlando, C. 1924. Lead the Precious Metal. Jonathan Cape.

Lynn WilliesProject LeaderPeak District Mining MuseumMatlock BathDerbyshireDE4 3NR

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lead miners made practical use of geologicalprinciples as early as the 17th century (Rieuwerts,1984). In the 18th century the course of the initialpart of Cromford Sough followed the strike of thelimestone/shale contact where excavation was easierthrough shale. The position of the contact wasobtained by down-dip projection from the outcropshowing that the soughers had some appreciation ofconcealed geology. The lead miners also used thebasic principles of stratigraphy and structure topredict whether or not they would intersecttoadstones in driving other soughs in the 18thcentury (Fig. 1).

Whilst most of the lead miners’ knowledge wasnever written down, some of it has been preserved inthe appendix to “An Inquiry into The Original Stateand Formation of the Earth” by John Whitehurst(1713-1788) (see Craven, 1996). This appendixrecorded the strata of limestone and interlayeredtoadstones on either side of the Derwent Gorge atMatlock by means of some of the first stratigraphicalsections ever published (Whitehurst, 1778). Thepositions of some mines and mineral veins depictedon Whitehurst’s sections confirms that he acquiredsome of his knowledge about their disposition fromthe lead miners. However, he misunderstood thenature of the bouldery alluvium beneath the riverbed and invoked a “gulf” full of boulders extendingto an unknown depth (Fig. 2). Whitehurst realizedthat there was a syncline between Matlock and theAshover inlier, but he found it difficult to showcurvature of the strata on his sections andaccommodated the axis with boulders fillinganother, downwards-expanding “gulf”.

A disciple of Whitehurst’s was White Watson(1760-1835). His geological tablets and Delineationbooks (1811; 1813) extended Whitehurst’s principleof a regular stratigraphical succession in the Matlockarea throughout the Peak District and into theDerbyshire coalfield. He established a stratigraphicalcolumn of 36 units in Derbyshire, noting subtledifferences in both lithology and palaeontology oflimestones, shales and gritstones. White Watson’sinlaid marble tablets were at first diagrammaticrepresentations of folded limestones and lavas,flanked by scarps of overlying shales and gritstones,but later he compiled detailed sections across muchof the county, basing the first on drawings by Farey(Ford, 1960; 1995; Torrens, 1994). White Watsonbuilt up large fossil collections for sale, 500 at atime, and some of these form the basis of museumcollections today. Watson and his colleague WilliamMartin set out to produce an illustrated catalogue ofDerbyshire fossils but it was eventually published by


The Growth of Geological Knowledge in thePeak DistrictTrevor D. Ford

Abstract: The development of geological knowledge in the Peak District from the 18thcentury to the present day is reviewed. It is accompanied by a comprehensive bibliography.

IntroductionGeology has changed in the last two centuries froma largely amateur “gentleman’s” science to aprofessional vocation. The results of professionalinvestigation in the Peak District have been built onthe amateur foundation and the works cited in thisreview demonstrate the change in approach. TheGeological Survey commenced a professionalapproach in the 1860-1880 period, continuedduring World War I and in the 1950s, but it was notuntil the 1970s that some intensive economicinvestigations were pursued. The GeologicalSurvey’s activities in the 20th century wereconcurrent with the development of GeologyDepartments in the nearby Universities, whereresearch grew slowly after World War I and morerapidly after World War II. However, there is stillroom for amateur investigation, as shown by theactivities of such organizations as the East MidlandsGeological Society.

As far as is known, the only previous attempts tosurvey the growth of geological knowledge in thePeak District were by Challinor (1949-1951), whoseviewpoint was biased towards the western margins ofthe Peak District, and the present author, who gavean outline of research on the limestone massif in theintroduction to his book on the Limestones andCaves of the Peak District (Ford, 1977). This reviewis an expanded version of a talk given at theSymposium held at the University of Derby onMarch 16th 1996, that date being the centenary ofthe first extra-mural classes in geology taught inDerby.

There are many published contributions to thegeology of the Peak District which space precludesmentioning herein. Only those works representingsignificant advances are included. Readers arereferred to Ford and Mason (1967) and Ford (1972)for comprehensive bibilographies up to those dates.Since then the pace of research has increased and asteady flow of publications has appeared since theabove-mentioned bibliographies.

Historical perspectiveThe Pioneers. The principles of stratigraphy areoften said to have been first formulated by WilliamSmith in Somerset where there was an economicstimulus with a coalfield adjacent to lead mines inthe limestones of the Mendip Hills, plus a sub-Triassic unconformity and overlapping Jurassic.Similar stimuli occurred elsewhere in other miningfields, particularly in the Peak District where the

TREVOR D. FORD


Fig. 1. A section of Basrobin Mine, Wensley, shows the lead miners’ prediction of strata to be penetrated (after Rieuwerts, 1984).

Fig. 2. A section across the Derwent Gorge at Matlock, showing alternating limestones and toadstones and the gulf full of brokenrocks beneath the river (Whitehurst, 1778).

Martin alone (Martin, 1810). Unfortunately Martinused a non-Linnean trinomial system ofnomenclature so that his names were later declaredinvalid according to the Rules of ZoologicalNomenclature, though some were adapted and arestill used for some well-known species, e.g.“Conchylolithus Anomites Pugnus” is still known asPugnax pugnus.

John Farey (1766-1826) inspired Watson’s latermore detailed sections. Farey was a polymath whopublished in various subjects, notably mathematics,music and geology (Ford and Torrens, 1989). Heprepared long stratigraphical sections of variousparts of Britain on rolls of paper: these unfortunatelyremained unpublished until discovered by Ford(1967). One such unpublished section lay across theAshover anticline (Fig. 3). John Farey was a friendand disciple of William Smith and came toDerbyshire in 1807 to produce what was in effect thefirst district memoir (Farey, 1811). This cataloguedthe strata of Derbyshire in such a way that a simplestratigraphical map could have been produced,although his book contained only a simple outlinegeological map. Farey started work on a detailedgeographical map of Derbyshire in the style ofSmith’s county maps but it was never completed andthe manuscript has only recently been discovered byHugh Torrens in a Californian library! Farey alsodrew a coloured, manuscript geological map of theAshover inlier, recently published by Torrens(1994), which is comparable to modern maps.Perhaps more important is that Farey recognized thenature of faulting and his book contained fold-outsheets of explanations of different classes of fault.However, he overstated his arguments by assigningparts of the unconformable contact betweenlimestones and Edale Shales to a Great Peak Fault.White Watson later corrected Farey in showing thatthe basset (outcrop) of the shale/limestone contactwas without faults over much of its course (Watson,1813).

These three pioneers, Whitehurst, Farey andWhite Watson, set geology on its feet in Derbyshirein much the same way as William Smith did aroundBath, but they did not really get the credit theydeserved as founders of the science of stratigraphy.Perhaps this was because three men were involvedinstead of one; perhaps the fact that they were notinvolved in canals as parts of a national transportsystem pushed them into the background. Even so,Farey was the first to publish William Smith’s systemof a stratigraphical succession and he helped Smithto extend his work over much of England.

All three pioneers also expressed ideas on theorigins of toadstone, effectively supporting Huttonand Playfair in regarding toadstones as ancientvolcanic rocks. Farey went so far as to suggest that itwas satellite attraction which raised the Massonanticline at Matlock, but White Watson disagreedand argued that volcanic pressure from within theEarth was a much more likely cause of up-folding.Whitehurst and Farey published brief notes on theorigin of mineral veins by lateral secretion. Watsonalso put forward ideas on the origin of the mineralveins from volcanic sources but only in unpublishedlecture notes. White Watson was the first lecturer ongeology in Derbyshire, delivering talks in Bakewellon a variety of geological topics for some 40 yearsuntil his death in 1835. A bound volume of printedsheets (effectively lecture notes) and sketches whichhe used as visual aids survives in Derby ReferenceLibrary.

Among the few other early geologists who may beconsidered alongside the pioneers is John Mawe(1766-1829) (Torrens, 1992). Mawe’s book (1802)preceded both White Watson and Farey, but he wasmore concerned with mines and minerals. Even so,he provided an early stratigraphic account andsection of the Castleton area. Profiles along severalvalleys showing the disposition and faulting of someof the toadstone outcrops were given in a littleknown private publication by Hopkins (1834).

THE GROWTH OF GEOLOGICAL KNOWLEDGE IN THE PEAK DISTRICT


Fig. 3. A section of the strata from Matlock across the Ashover anticline from an unpublished diagram by John Farey (1808).

Mid to Late 19th century prehistory. ThoughWhite Watson mentioned the occurrence of bones ofancient animals in caves, e.g. an “elephant’s” skull inBall Eye Cavern near Bonsall, it was not until the1820s that the concept of antediluvian animals cameto the fore through the work of Dean WilliamBuckland at Oxford. One of his examples was therhinoceros skeleton found by lead miners in theDream Cave near Wirksworth (Buckland, 1823).Unfortunately the specimen has not survived so it isimpossible to identify which species of rhinoceroswas found there. Both Darwin’s “Origin of Species”in 1859 and the growth of prehistoric archaeologyelsewhere had their spin-offs in the Peak District,where cave excavation reached a climax with thefinding of Devensian faunas at Windy Knoll andother caves (Dawkins, 1874; 1875; Dawkins andPennington, 1877; Pennington, 1874; 1875; 1877).Contemporary excavations at Creswell on theDerbyshire-Nottinghamshire border yielded bothextinct mammals and human artefacts (Mello,1876) and inspired a more intensive search in thePeak District, but it was not until the turn of thecentury that a “Pliocene” fauna was found in afissure at Doveholes (Dawkins, 1903); it was laterre-determined as Cromerian (Spencer and Melville,1974). Some of the above writers and othersspeculated on the relationship of such deposits toearly ideas of glaciation and denudation. Theconcept of denudation chronology, however, wasslow to develop and little was published on thesubject until the 1930s.Mid 19th century Consolidation. The middlepart of the 19th century was a period ofconsolidation rather than major advances ingeological knowledge. There was much theoreticaldevelopment of the subject elsewhere but the PeakDistrict played little part in it.

Systematic knowledge of the fossils of the PeakDistrict grew in the mid to late 19th century with thepublication of several Palaeontographical Societymonographs on brachiopods (Davidson, 1858-1863), corals (Milne-Edwards and Haime, 1852-1854), trilobites (Woodward, 1883), Foraminifera(Brady, 1876) and ostracods (Jones et al., 1875).Numerous papers discussed less important groups offossils. These and the early monographs have beensuperceded by later revisions but, to this day, thereis no published, illustrated catalogue of the manyCarboniferous fossils from the Peak District.

The growth of mineralogy as a science stimulatedthe catalogue of Greg and Lettsom (1858), whichprovided descriptions of some new minerals inDerbyshire, in particular matlockite and cromfordite(the latter now known as phosgenite).

Geological Survey officers commenced work in thePeak District in the mid-19th century and producedthe early hachured 1 inch to 1 mile maps andmemoirs (Green et al., 1869). These collatedgeological knowledge, incorporating data from thelead mining industry. However, they failed tosystematize Whitehurst, Watson’s and Farey’s

subdivisions of the limestone succession, and theirmaps coloured all the limestone outcrop in the sameshade of blue, making no distinctions between thelimestone formations that were to be named later.

Stokes’ (1879) review of the economic geology ofDerbyshire provided a survey of a variety of mineralproducts with commercial potential, including leadand zinc ores, iron ore, fluorspar, baryte, calc-spar,chert, umber and coal. His later review of the thendeclining lead mining industry in 1880-83 includeda map of the veins and a few geological observations.20th century Geologists and GeologicalInstitutions. Much of the early growth of geologicalknowledge in the Peak District can be put down tothe work of amateurs or semi-professionals such asWhite Watson and Farey (1811). Professionalsstarted to enter the area with early GeologicalSurvey (Green et al., 1869, 1887) and it was notuntil the early 20th century that academic geologywas developed in the Universities of Sheffield andManchester and later in Nottingham. Derby had towait many years before an Earth SciencesDepartment was established in its College of HigherEducation, recently established as the University ofDerby. The small numbers of staff in the UniversityGeology Departments before World War II meantthat few had much opportunity for research either inthe Peak District or anywhere else; post-graduatestudents were a rarity. Such research as was donewas mostly concerned with practical geology in thecoalfields either side of the Peak District. However,Fearnsides (1933) gave an early structural analysisof the Peak District and its surroundings. Hiscolleague in Sheffield University, Shirley (togetherwith Horsfield) (1940, 1945) followed with detailedmapping of the Carboniferous Limestone. Ofmuseum geologists, only Jackson (1925; 1926;1927) made any significant addition to knowledgewith his studies of Millstone Grit stratigraphy andpalaeontology around Edale and Castleton.

While the general distribution of undergroundwater resources was well known, it was not until1929 that the data were collected in a Wellsand Springs Memoir (Stephens, 1929). Thegeochemistry of these waters was later investigatedby Downing (1967) and Edmunds (1971). Theunderground catchments were delineated byChristopher et al., (in Ford, 1977) and the leadminers’ soughs catalogued by Rieuwerts (1987).

The search for oil resources during World War Iwas largely abortive but the oil seeps at Hardstoftmaintained an interest in the Peak District (Falconand Kent, 1960). Boreholes in Edale and Alport in1938 and later at Gun Hill, Staffs (Hudson andCotton, 1945), enabled detailed correlations and faciesanalyses but failed to yield hydrocarbon resources.

The Geological Survey started a re-survey of thePeak District in the late 1930s but it was put intoabeyance during World War II and not continueduntil the 1950s. The set of maps and memoirscovering the whole Peak District was completed inthe 1980s.

TREVOR D. FORD


Re-investigation of mineral resources duringWorld War II produced reports on fluorspar andbaryte. Although an economic memoir on the leadmines and veins was started by C. A. U. Craven andJ. V. Stephens of the Geological Survey in the 1950s,it was never completed and there is still nocomprehensive overview comparable with thedescriptive memoirs compiled for the NorthPennines and Cornwall. Reviews of South Penninebaryte and fluorspar resources were compiled byDunham and Dines (1945) and by Dunham (1952).Detailed studies of the limestone and dolomiteresources were produced by the Geological Surveyin the 1980s (see summary by Harrison and Adlam,(1985)).

Specific advancesCarboniferous Limestone. Whitehurst (1778)and Watson (1811) established a sequence ofalternating limestones and toadstones, and Farey(1811) named these, in downward succession, the1st Lime, 2nd Lime etc. Furthermore, Farey’ssimple outline map differentiated the 1st Lime ascovering roughly the area of outcrop of Brigantianstrata as known today. After these pioneer studies,little progress was made towards establishing adetailed stratigraphical succession within thelimestones for another 50 years.

The early work of the Geological Survey (Greenet al., 1869, 1887) did not attempt to subdivide theCarboniferous Limestone. Soon after Vaughan’sestablishment of a zonal scheme based on corals andbrachiopods in the Avon Gorge at Bristol, Sibly(1908) was able to show that most of the White Peakwas composed of limestones belonging to Vaughan’suppermost zones (D1 and D2). This was restated inFearnsides’ (1932) review.

In the pre-war run-up to the Geological Survey’sremapping, Cope (1933, 1939) described andnamed the sequence in the most fully exposedsection of the Wye Valley. Shirley and Horsfield(1940; 1945) followed with detailed stratigraphical

papers on the Castleton and Monyash-Wirksworthareas. Unfortunately, they misunderstood therelationships of massif and reef limestones aroundCastleton, regarding the latter as submarine screesbanked against cliffs eroded into a massif of olderlimestones (Fig. 4). An alternative insight into faciesrelationships was provided by Hudson and Cotton’s(1945) analyses and detailed stratigraphical sectionsderived from the deep boreholes in Edale, Alportand Gun Hill. The contrasts between massif, reefand basin facies were shown to have resulted fromsedimentation on a block surrounded by deeperwater. Soon afterwards, the rubber chemist andamateur geologist Parkinson (1947) reinterpretedthe relationships at Castleton showing that the reeffacies was contemporary with the massive facies,with a lateral passage between the two. Parkinson(1953) elaborated on the structure of the Castletonreef belt, providing palaeo-contours of the fore-reefslope. The palaeocology of the specialized reeffaunas reflected the facies changes both at Castletonand in the similar reef belt on the western margin ofthe limestone massif around Earl Sterndale(Wolfenden, 1958) (Fig. 5). The complex faciesrelationships in the Dovedale-Manifold Valley areawere investigated by Parkinson (1950), and theadjoining Weaver Hills by Ludford (1951). Somerevision became necessary as a result of joint studiesin the intervening area (Parkinson and Ludford,1964).

The “reef” facies, variously referred to as knoll-reefs, apron reefs and build-ups, are perhaps bettercalled mud-mounds in view of their lack of anorganic framework like modern coral reefs (Bridgesand Chapman, 1988; Bridges et al., 1995). Thoughthe evidence is limited, it seems certain that themud-mounds were built by microbial action(Gutteridge, 1995) particularly by algae andCyanobacteria (Pickard, 1996). The shape of themud-mounds was controlled by the depth of waterat initiation and by the rate of subsidence. On ramps(sloping sea floors), contemporary mud-moundscould be wide and low in shallow water but narrowand highly domed at the margins of deeper water



Fig. 4. Shirley’s proposed relationship of the “reef” limestones lying unconformably against an eroded cliff of the massiflimestones (modified after Shirley and Horsfield, (1940).

TREVOR D. FORD


Fig. 5. Sketch map and section of the facies relationship of the reef and massif limestones at Castleton (modified after Wolfenden,1958).



Fig. 6. Simplified map of the subdivisions of the Dinantian strata of the Peak District (reproduced from Aitkenhead andChisholm, 1982, by permission of the Director of the British Geological Survey; © NERC).

basins (Gutteridge, 1995; Bridges et al., 1995).Bioclastic limestones rich in crinoid debris bothflanked the muds-mounds and accumulated onplatform margins (Gawthorpe and Gutteridge,1990). Some degree of water-depth control on thedistribution of various species of brachiopods,molluscs and trilobites was deduced by thepalaeobathymetric studies of Broadhurst andSimpson (1973).

The Woo Dale borehole extended knowledge ofthe concealed sequence beneath the lowest exposedbeds (Cope, 1949; 1973). It penetrated 273m oflargely dolomitic limestones resting on pre-Carboniferous volcanic rocks beneath the WyeValley (Cope, 1949; 1973). The Woo Dalelimestones themselves were shown to be partlydolomitized by Schofield and Adams (1985; 1986).The Eyam borehole, though starting at a higherhorizon, penetrated over 1600m of limestones withanhydritic beds at the bottom before entering slatesof probable Ordovician age (Dunham, 1973). Thisthick sequence demonstrated that transgression onto the Derbyshire massif started much earlier(Tournaisian?) than at Woo Dale, and that thebasement surface was either sloping or faulted.

The higher (Brigantian) part of the sequence wasinvestigated around the Hope cement quarry (Edenet al., 1964) where the marginal complex is largely aseries of mud-mounds and shoals of crinoidalcalcarenite. Farther south, the Asbian-Brigantiansequence and accompanying lavas were mapped inMonsal Dale by Butcher and Ford (1973). Adeeper-water facies with thin dark limestones, someof which are laminated with small slump structures,occurs in the mini-basin around Ashford-in-the-Water (Adams and Cossey, 1978). The flankinghighs had contemporary mud-mounds nearMonyash (Gutteridge, 1987; 1995). Microfacies inthe Asbian marginal reefs and lagoonal limestonesaround Hartington were studied by Sadler (1966).The sequence in the main part of Dovedale, with itscomplex of “reef” limestones of two different ages,was described by Parkinson (1950). The marginalreefs in upper Dovedale were later shown to bear aclose resemblance in both age and palaeontology tothe marginal reefs of Castleton (Wolfenden, 1958).The sequence in the basinal facies of the ManifoldValley to the west, though much disturbed by bothfolding and faulting, was delineated by Prentice(1951). In the far southwest of the White Peak, theWeaver Hills stratigraphy was described by Ludford(1951). The earlier series of reefs in the Dovedalearea were later shown to be relatively deep-watermud-mounds comparable to the Waulsortian faciesof Belgium (Miller and Grayson, 1982; Bridges andChapman, 1988; Bridges et al., 1995). Across theCastleton-Bradwell margin of the massif, lateDinantian (Brigantian) sedimentation was shown tobe an accumulation of migrating shoals of crinoidalcalcarenite in contrast to the marginal “reef”complex in Asbian times (Gutteridge, 1989; 1990;1995; Gawthorpe and Gutteridge, 1990).

Cyclic emergence of the carbonate-coveredDerbyshire Block with the intermittent formation ofpalaeosols and palaeokarstic surfaces was deducedfrom sections along the Wye Valley (Walkden, 1974)and in the Wirksworth-Grangemill area (Oakman,1984; Walkden et al., 1981). At Crich, the cyclicnature of the Brigantian sequence was related totransgression-regression cycles (Bridges, 1982).The effect of this emergence on diagenesis, withresultant multiple generations of cementation, wassubsequently discussed by Walkden and Williams(1991). Using cathodoluminescence to distinguishsuccessive phases, the later phases of diagenesis haverecently been related to mineralization and tohydrocarbon emplacement (Hollis and Walkden,1996).

Dinantian sedimentation in the concealed EdaleBasin was first investigated following drilling of theEdale borehole (Hudson and Cotton, 1945b). Amore detailed interpretation was given byGutteridge (1991), who also suggested that theadjacent limestone massif might be bounded byconcealed basement faults.

Dolomitization is widespread in the upperlimestones of the southern Peak District (Parsons,1922). Although commonly attributed to the sub-surface effects of a Permian transgression, it isusually regarded as an early phase of mineralization(see later section on mineralization).

Silica is common in some limestone formations inthe form of chert nodules, authigenic quartz,silicified fossils or as quartz rock. On the other hand,some limestones, particularly mud-mounds, arealmost devoid of silica. Whilst some of thedistribution in Brigantian beds has been ascribed tomobilization of silica from altered volcanics (Orme,1974) no full study is yet available. Massive cherts inthe highest beds around Bakewell were once minedfor use in the Potteries (Bowering and Flindall,1998).

Palaeontology has been incidental to most of thestratigraphical and sedimentological studies. Lists offossils were given in many publications but therewere few illustrations and no guide to identification.Parkinson (1954), however, laid some of thefoundations of statistical palaeontology with studiesof brachiopod populations and community growthpatterns based on collections from the fore-reeflimestones of Treak Cliff, Castleton. Facies controlof faunal distribution around Castleton and upperDovedale was noted by Wolfenden (1958) and in theBrigantian mud-mounds near Monyash byGutteridge (1990; 1995 and Bridges et al., 1995).Tilsley (1988) noted that, at Castleton, trilobiteremains seemed to be concentrated at intermediatedepths on fore-reef slopes. The Eyam boreholeenabled Strank (1985) to describe the Tournaisianto Brigantian evolution of foraminifera and otherfaunas.

The Geological Survey returned to the PeakDistrict during the 1950-1970 period, as a resultof which maps at 1:50,000, 1:25,000 and 1:10,000

TREVOR D. FORD


(or 10,560) scales are now available. Descriptivememoirs also cover the whole Peak District (Smithet al., 1967; Stevenson and Gaunt, 1971;Aitkenhead et al., 1985; Chisholm et al., 1988).Nomenclature was standardized and a summarymap produced by Aitkenhead and Chisholm (1982)(Fig. 6). The series of formational names produced

in different parts of the Peak District was alsosystematized by Aitkenhead and Chisholm (1982)(Fig. 7), although some revision became necessaryowing to the later recognition of subtle facieschanges around Matlock (Chisholm et al., 1983).Although not usually listed among the main authors,the Geological Survey’s biostratigraphers, notably



Fig. 7. Stratigraphic tables of Dinantian subdivisions in the Peak District: a. Central, northern and eastern Peak District; b.southwestern Peak District (Stage boundaries are uncertain in the southwest) (reproduced with modifications from Aitkenheadand Chisholm, (1982), by permission of the Director of the British Geological Survey; © NERC).

DINANTIANSTAGES

LONGSTONEMUDSTONES

EYAMLIMESTONES Ashford Beds

Cawdor Group

Cawdor Shale

Cawdor Limestone

MatlockLimestone

LathkillLimestone

Via GelliaLimestone

Wolfscote DaleLimestone

Iron TorsLimestone

Alsop MoorLimestone

HootonwoodLimestone

Cawdor Limestones

Matlock Group

HoptonwoodGroup

Griffe Grange Bed

Upper Limestones

Lean Low Beds

Hard Dale Beds

Vincent House Beds

Monsal Dale Beds

Priestcliffe BedsUpper Lava

Miller’s Dale Beds

Lower Lava

Chee Tor Rock

Daviesiella Beds

Station Quarry Beds

MONSAL DALELIMESTONES

BEE LOWLIMESTONES

WOO DALELIMESTONES

REGIONALFORMATION

NAMESWye valley

(Cope 1933, 1937 & 1958)

Matlock area(Smith and others

1967)

Wirksworth area(Frost and Smart

1979)

Monyash andWirkswoth(Shirley 1953)

North-east ofHartington

(Sadler and Wyatt 1966)

Wolfscote Dale &Alsop Moor

(Parkinson 1950)

BRIGANTIAN

ASBIAN

HOLKERIAN

LOCAL AND EARLIER CLASSIFICATIONS

DINANTIANSTAGES

BRIGANTIAN

MIXONLIMESTONE - SHALES

andWIDMERPOOLFORMATION

ECTONLIMESTONES

andHOPEDALE

LIMESTONES

MixonLimestone - Shales

Mixon Limestonesand

Ecton Limestones

ManifoldLimestones with Shales

MILLDALELIMESTONES

RUE HILLDOLOMITES

REDHOUSESANDSTONES

(Carboniferous or Devonian)

MILLDALELIMESTONES

KEVINLIMESTONES

Calton Limestones

Cementstone Series

Massive Series

Brownlow Mudstones

Posidonomya Beds Hollington End Beds

Bull Gap Shales

Waterhouses Limestone

Forest Hollow Beds

Solenopora Beds

ManifoldLimestone-with-Shales

Cauldon Low Limestoneand

Weaver Beds

Gag Lane Limestone

Milldale Limestone

Apestor & WarslowLimestones

Waterhouses Limestoneand Crassiventer Beds

ManifoldLimestone-with-Shales

ASBIAN

HOLKERIAN

ARUNDIAN

CHADIAN

COURCEYAN

REGIONAL FORMATION NAMES

(Aitkenhead & Chisholm, 1982)

Mixon & Manifold Valley(Hudson in Hudsonand Cotton 1945a)

Dovedale & Swinscoe(Modified from Parkinson 1950

andParkinson and Ludford 1964)

Manifold Valley(Prentice 1951)

Weaver Hills(Ludford 1951)

LOCAL AND EARLIER CLASSIFICATIONS

M. Mitchell, W. H. C. Ramsbottom. N. J. Riley, andA. R. E. Strank identified thousands of fossils listedin the Memoirs and contributed much tounderstanding of the stratigraphical and structuralrelationships. The Survey also published 1:25,000scale maps of educationally important areas (Edaleand Castleton, Millers Dale, Matlock andWirksworth) with concise descriptions in theirmargins. Almost the whole White Peak area wascovered at the latter scale in maps accompanyingthe limestone resources assessment reports notedbelow.

As part of the general systematization ofchronostratigraphy and nomenclature in the LowerCarboniferous (Avonian, later Dinantian), a series ofstages were defined in accordance with the rules ofstratigraphic nomenclature (George, 1972; Georgeet al., 1976). Based on fossil assemblages from type-sections in various parts of Britain, the stagesseemed to correlate with transgression-regressioncycles identified by Ramsbottom (1973). The stagesCourceyan, Chadian, Arundian, Holkerian, Asbianand Brigantian (Fig. 7) replaced the old coral-brachiopod zones, K, Z, C, S and D, which couldonly be applied to the shallow water shelf facies. Thefirst of these stages (Courceyan) appears to havelittle or no representation in the Peak District,though some of the Rue Hill Sandstones at thebottom of the Cauldon Low borehole in the WeaverHills (Chisholm et al., 1988) may be of this age orpossibly even late Devonian.

Substantial surface and subsurface lithologicaldetail was provided by the surveys of limestone anddolomite resources carried out by the Institute ofGeological Sciences for the Department of theEnvironment by Cox and Bridge (1977), Cox andHarrison (1980), Harrison (1981), Bridge andGozzard (1981), Gatliff (1982) and Bridge andKneebone (1983). Many shallow boreholes yieldedboth lithological and stratigraphical detail for almostthe whole limestone outcrop. The results weresummarized by Harrison and Adlam (1985).The Toadstones. The assemblage of basalt lavas,tuffs and ashes commonly known as toadstonesintrigued early geologists in view of the late 18thcentury controversy between Werner, who thoughtthat all ancient basalts were precipitates from aprimaeval sea, and Hutton, who correctly regardedthem as volcanic outpourings. As noted above,Whitehurst, Watson and Farey were adherents of theHuttonian theory. They thought that there were twoprincipal horizons of toadstone in most of the PeakDistrict, but Hopkins (1834) argued that theremight be three toadstones in some locations but onlyone in others (Fig. 8). Later, as many as seventoadstone horizons were identified in Mill CloseMine at Darley Dale (Traill, 1939; Shirley, 1949).

The end of the 19th century and early 20th saw amajor advance in knowledge with the publication ofAllport’s (1874) and Bemrose’s (later ArnoldBemrose) works on the petrography of the lavas andashes (Bemrose, 1894). Bemrose later mapped the

distribution of toadstones throughout the WhitePeak (1907). His mapping demonstrated thepresence of several main lava flows as well as sheetsof tuff and patches of vent agglomerate. A few sillswere also recognised. Although there are two mainlavas in both the Castleton-Millers Dale and theMatlock areas, they lie at different horizons and laterwork showed that a simple correlation of the lavas inthose areas was misleading. Bemrose’s studies couldhave provided the basis for a detailed stratigraphicalmap of the White Peak’s limestones, but he wascontent with mapping the toadstones and giving ageneral review of the area (Bemrose, 1910a).Wilcockson (in Fearnsides, 1932) and laterMacdonald et al. (1984) added petrographical detailshowing that the basalts ranged in composition fromolivine-rich alkaline basalts to olivine-poor tholeiites.Detailed studies of the lavas in the Matlock areaarising from the limestone resources investigationsnoted above led to the Lower Matlock Lava beingrecognized as multiple lava flows, intercalated withthick tuffs (Chisholm et al., 1983). Webb and Brown(1989) provided both a new map of the toadstoneoutcrops (Fig. 9) and a digest of geochemical data.

Interbedded with the limestones both above andbelow the main lavas are thin greenish clay layersknown as wayboards. Their origin as volcanic ashfalls, sometimes accompanied by soil-formingprocesses, was described by Walkden (1972), whofound that some ash falls were sufficient to result intemporary emergence above sea level.

The basalts of Calton Hill, near Taddington, werefound to include the unusual feature of olivinenodules (Bemrose, 1910b). The opening of a quarrythere in the 1920s, in what appeared to be a volcanicneck, stimulated research into these basalts,particularly by the Russian emigré Tomkeieff(1928). The basalts included massive, columnar andvesicular varieties, and there was secondary

TREVOR D. FORD


Fig. 8. Alternative sections with of two or three toadstones,near Aldwark (from Hopkins, 1834).



Fig. 9. Distribution of Carboniferous lavas, vents and sills. LAVAS: UMB, Upper Millers Dale; LMB, Lower Millers Dale; CD,Cave Dale; CRD, Cressbrook Dale; SWB, Shacklow Wood; CBB, Conksbury Bridge; LOB, Lathkill Lodge; LRB, Lower Matlock;WMB, Winster Moor; URB, Upper Matlock; R. Rowsley Boreholes. VENTS: SV, Speedwell; CH, Calton Hill; GM, Grangemill.SILLS: PFS, Peak Forest; PS, Potluck; WSS, Waterswallows; TDS, Tideswell; BS, Bonsall; IS, Ible; TUFFS:TS, Tissington; AS,Ashover (reproduced from Webb and Brown, 1989, by permission of the Director of the British Geological Survey; © NERC).

LOB

SV

GM

TS

R

AS

mineralization with many quartz veins containinghematite inclusions. A pattern of boreholes sunk bythe quarry company to prove resources showed thatthe whole pile had a saucer-shaped base; no feederpipe was detected. Olivine nodules within themassive basalt were shown by Hamad (1963) tocontain a small proportion of pyroxenes. It is stilldebatable whether the nodules representconcentrations of ferro-magnesian minerals broughtup from deep in the magma chamber or whetherthey might have been derived from the Earth’smantle. The former seems to be the favouredhypothesis at present.

A borehole beneath the cement works at Hoperevealed an unexpected pile of mostly pillow lavas(Fearnsides and Templeman, 1932). These appearto be marginal to a tuff mound later found beneaththe adjacent quarry (Eden et al., 1964; Stevensonand Gaunt, 1971).

In 1933 Cope described tholeiite dykes in GreatRocks Dale. In 1997 he proposed that these mightrepresent feeders for the lavas. Elsewhere the lavaswere thought to emanate from scattered vents,though demonstrating the physical connection hasnot generally been possible.

As noted in the Carboniferous Limestone sectionabove, the officers of the Geological Survey re-surveyed the Peak District after World War II,thereby providing the first detailed maps oftoadstone outcrops since Bemrose (1907). Duringthis resurvey, boreholes near Ashover demonstrateda thick volcanic pile beneath that anticline(Ramsbottom et al., 1962). Later, Walters andIneson (1981) provided a detailed analysis of thevolcanic history.Millstone Grit. At the base of the Millstone Gritsuccession, the thick marine Edale Shales were atfirst correlated with the Yoredale Beds of the NorthPennines until palaeontological work showed thatthis was partially incorrect and that the lowerYoredales were of Dinantian age. The basal contactof the shales with the limestone, regarded as due toa fault complex by Farey (1811) and the earlyGeological Survey (Green et al., 1869; 1887), wasshown to be at least partly a buried-landscape typeof unconformity by Jackson (1925) and Hudson(1931); they demonstrated that the shales werebanked against eroded fore-reef beds largely ofAsbian age. A massive boulder bed at the shale/limestone contact around Treak Cliff, Castleton,indicated that perhaps 100m thickness of Brigantianlimestones had been removed in latest Brigantian toearliest Namurian times (Simpson and Broadhurst,1969). Their implication was that uplift ofcomparable magnitude had taken place and that thelimestone had been eroded subaerially.

The thick sequences of alternating shale andcoarse sandstone (gritstone) noted by Watson(1811) and Farey (1811) forms the Millstone Gritframe around the White Peak, culminating in theplateau of Kinderscout in the north — the so-calledDark Peak. Farey’s unpublished section of 1808

numbered Grit horizons in upward order (Fig. 3).The beds were mapped by early officers of theGeological Survey (Green et al., 1869; 1887) wholaid the foundations of the sandstone nomenclatureused today, namely Shale Grit, Kinderscout Grit,Chatsworth Grit, Ashover Grit and Rough Rock.However, the equivalent beds in northeastStaffordshire were unfortunately referred to as FirstGrit, Second Grit, etc., leading to mis-correlation(Fig. 3) until it was sorted out by the palae-ontological work of Hind (1897, 1898), Jackson(1926, 1927) and particularly Bisat (1924). Bisatnotably established the Namurian age of theMillstone Grit by goniatite correlation with theBelgian sequence. A series of mainly proto-quartziticsandstones in the lower part of the Millstone Gritwas later named the Minn Beds in northStaffordshire (Holdsworth, 1963; Ramsbottomet al., 1978).

In post World War II times the details of theNamurian strata have been mapped and describedin Geological Survey Memoirs (Eden et al., 1957;Smith et al., 1967; Stevenson and Gaunt, 1971;Aitkenhead et al., 1985; Chisholm et al., 1988). Themapping stimulated sedimentological studies bycontemporary academics, notably Allen (1960),Holdsworth (1963) and Collinson (1968; 1969).Bisat’s (1924) notation of goniatite zones E1, E2, H,R1, R2, and G was replaced by a sequence of stagesnamed after type areas; Pendleian, Arnsbergian,Chokerian, Alportian, Kinderscoutian, Yeadonianand Marsdenian. The relationship of localsuccessions to these stages was discussed byRamsbottom et al. (1978) (Fig. 10). Thesechronological stages were regarded as almostsynchronous with a series of transgression/regressioncycles referred to as mesothems (Ramsbottom,1977). Eleven mesothems were recognized, but theconcept was later regarded as too simplistic byHoldsworth and Collinson (1988). Applying thehypothesis of sequence stratigraphy, Read (1991)referred the lower parts of each sandstone/shalecycle to a low-stand system tract, whilst the massivesandstones represented high-stand system tracts andthe whole package was explained as due to glacial-eustatic sea-level oscillations. The concept ofsequence stratigraphy now proposes that the simpleearly idea of repeated rises of sea-level should bereplaced by one involving both rises and falls.

The sedimentology of the Millstone Grit wasoutlined as early as 1859 by Sorby, and enlargedupon much later by Gilligan (1919), who explainedthe Millstone Grit as the deposit of a massive delta,building out southwestwards into the PennineBasin. The coarse sandstones of the north and eastflanks of the Peak District exhibit current-beddingthat indicates derivation from the north andnortheast. Preceded by the deep-water Edale Shales,the deltas did not build out into the Peak Districtuntil Kinderscoutian times. Remnants of the EdaleShales on top of the limestone massif showcondensed sequences which contrast with the thick

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Fig. 10. Namurian correlation between North Staffordshire and North Derbyshire (after Ramsbottom et al., 1978).

mudstones of the Edale and North Staffordshire‘Gulfs’. The deltaic sandstones have a variablecontent of feldspar and mica indicating a source inmetamorphic rocks like those of the ScottishHighlands.

By contrast the earliest sandstones, the Minn Bedsof the Staffordshire Gulf, were proto-quartziticturbidites of Pendleian to Kinderscoutian age. Theywere deficient in feldspar and mica and were derivedfrom a southerly source, the Midlands land-mass(Trewin and Holdsworth, 1973). FromKinderscoutian times onwards, deltas with coarsefeldspathic sandstones derived from the north alsobuilt out into the Staffordshire Gulf.

The sedimentological studies of Allen (1960),Walker (1966), Collinson (1968, 1969), Morris(1969), Trewin and Holdsworth (1973), Chisholm(1977), Jones (1980), Jones and Chisholm (1997)and Hampson (1997) have distinguished suchfeatures as delta-top aggradation, prograding slopesheets, overbank splays, channel-fills, proximalturbidite fans, distal aprons, offshore muds andgrowth faults (Fig. 11). Most importantly, a changeof view has emerged from simple stacking of deltasone on top of the other to a concept of laterally pro-grading fluvio-deltaic systems. For example, Jones(1980) showed that the Ashover Grit was fed intothe South Pennine basin from a southeast direction,by-passing the thick pile of Kinderscout andChatsworth Grits and reaching far enoughwestwards to form the Roaches Grit. Recent studieshave shown that the Ashover Grit and its correlativeRoaches Grit in Staffordshire filled a palaeo-valleyup to 80m deep cut across the southern margins ofthe preceding Kinderscout delta complex (Jones andChisholm, 1997).

The Tertiary Silica Sand Pocket Deposits.Worked for refractory brick manufacture to a limitedextent in the late 18th century, and also testedunsuccessfully for china clay, the silica sand pocketsdid not attract much attention from geologists untilBrown’s (1867) and Maw’s (1867) descriptions.Their economic importance was investigated byHowe (1897; 1918; 1920) but the deposits in thesixty or so pits (Fig. 12) were not described in anydetail until Yorke’s private publications (1954-61).Long regarded as Triassic outliers (Kent, 1957), thelate Cenozoic age of the Pocket Deposits was notestablished until much later when Walsh et al.(1972) formally named the sands and clays as theBrassington Formation. They showed that there wasonce a continuous sheet at least 45m thick overmuch of the southern part of the Peak District,composed of three members:3. Kenslow Member: grey clays with fossil plants;2. Bees Nest Member: coloured clays;1. Kirkham Member: white and yellow sands with

pebble bands.In spite of the former extent of the BrassingtonFormation, these three members are now preservedonly as a result of sagging into subsidence collapse“pockets” (Fig. 13), but a continuous sheet of thesefluvial sediments is thought to have once formed abraided river plain across much of the southern PeakDistrict (Walsh et al., (1972).

The fossil plants in the Kenslow Member werelisted by Boulter (1971), who deduced a lateMiocene to early Pliocene age. Quartzite pebbles inthe sands were deduced to have been derived fromthe Triassic Sherwood Sandstones which now occuras a low, north-facing escarpment around HullandWater, some 8km south of Brassington. The

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Fig. 11. Block diagram of the different facies of Millstone Grit deltaic sediments in the Peak District (modified after Collinson,1968).



Fig. 13. Diagrammatic section through a typical pocket deposit (modified after Dalton et al., 1988, with permission from theGeographical Association).

Fig. 12. Sketch-map to show thedistribution of the Neogene BrassingtonFormation in the Peak District (fromFord, 1977).

Limestone boundary with shales

Dolomitized limestoneareas

Possible pockets

Pebbles in soil

Miles

Km

0

2 3 41 2 3

Brassington Formation

HubberdaleMine

escarpment appears to have retreated from a formerextent covering the southern part of the limestonemassif. The fact that the escarpment is now at alower altitude than the silica sand pockets suggeststhat there has been differential uplift of thelimestone plateau since the early Pliocene (Walshet al. 1972).The Quaternary. Often regarded by 19th centurygeologists as “the muck” on top of the real geology,Quaternary deposits are thin and patchy over mostof the Peak District and have received comparativelylittle attention.

Passing remarks concerning Pleistocene mammalremains in caves were made by White Watson(1811), who recorded an elephant skull alleged tohave been found in Ball Eye cave near Bonsall. Arhinoceros skeleton was found in the Dream Cavenear Wirksworth (Buckland, 1823). It was not untilthe 1870s that systematic digging started (Dawkinsand Pennington, 1877). A Pliocene fauna found atDoveholes (Dawkins, 1903) was later re-determinedas probably Cromerian in age, perhaps one millionyears younger (Spencer and Melville, 1974). Fromthe 1930s onwards, Elderbush Cave and other cavesin the Manifold Valley and Dovedale area yieldedimportant, later Pleistocene sequences and faunas(Bramwell, in Ford, 1977).

The early Geological Survey (Green et al., 1869;1887) commented on the patchy representation ofglacial drift in the Peak District, and little furtheradvance was made until Jowett and Charlesworth(1929) analysed the directions of ice streams acrossthe White Peak and found little evidence of morethan a single glaciation. However, an analysis of riverterraces along the Derwent valley by Waters andJohnson (1958) showed that there were ‘high’ and‘low’ level deposits which could be related to“Older” and “Newer” Drifts, suggesting at least twoepisodes of glaciation. Further discussion on therelationship of tills, terraces and drainage diversionand their implications for glacial chronology, wasput forward by Straw and Lewis (1962) and byStraw (1968). Drainage patterns and terraces in theBuxton — Chapel-en-le-Frith area were alsoinferred to support two glacial episodes (Johnsonand Rice, 1961; Johnson, 1967; Burek, 1977)(Fig. 14). Burek (1991) has more recently shownthat two distinct tills can be distinguished by theirclay mineralogy.

Widespread yellowish silty clays on the limestoneplateau were interpreted as bioturbated loess byPigott (1962). Representing wind-blown detritusfrom the surrounding Millstone Grit areas, they areprobably largely Devensian in age, though there maybe earlier deposits of unproven age. Materialapparently derived from these is intermixed withoutwash sands in cave sediments (Noel et al., 1984;Ford, 1986).

A starting point for a chronological sequence ofPleistocene events was provided by the recognitionof the Mio-Pliocene age of the BrassingtonFormation (Walsh et al., 1972). Noting the work of

Beck (in Ford, 1977), Burek (1977) was able tobuild up a tentative history of Pleistocene events asthey relate to cave formation. The chronology wasdeveloped further by Ford’s (1986, 1996) analysis ofthe evolution of the Castleton cave systems, basedpartly on morphology and partly on uraniumdisequilibrium dates on stalagmites (Ford et al.,1983). The caves’ relationship to the evolution ofsuch landforms as the Winnats Pass has also beendiscussed by Ford (1987).

Cave sediments around Matlock have yieldedpalaeomagnetic evidence of a pre-Anglian glaciationat around 780,000 years BP (Noel et al., 1984). Theglacial/interglacial history is critical in the analysis ofthe evolution of the Derwent Gorge at Matlock(Ford, 1997) and further dating and research areneeded. Similar glacial-related sediments in ancientcaves intersected by quarrying at Eldon Hill, nearCastleton, still await a full description.

The problem concerning whether the high leveldrifts represent a different glaciation (Anglian?) fromthe low level drifts on terraces (Wolstonian?)highlights the deficiencies in knowledge. The highlevel drifts, at least in the southern part of thelimestone area, contain a high proportion of materialderived from the Trias via the BrassingtonFormation, whilst the low level till has a highproportion of Carboniferous material with rare LakeDistrict erratics. In short, the details of thePleistocene glacial history of the Peak District stillawait full analysis and understanding.

Landforms such as gritstone tors (Palmer andRadley, 1961), dry valleys (Warwick, 1964),landslides (Skempton et al., 1989), dolomite tors(Ford, 1963), caves (Ford, 1977, 1986), outwashsheets (Johnson, 1967) and anomalous gorges (Fordand Burek, 1976) such as the Winnats Pass (Ford,1987) and Derwent Gorge at Matlock (Ford, 1997),demonstrate the diversity of geomorphology inthe Peak District. Useful summaries of thegeomorphological history have been provided byDalton et al. (1988; 1990; 1999).Structure. The general structural pattern of the“Derbyshire Dome” and its subsidiary folds wasknown early in the 19th century with simple sketchmaps produced by Farey (1811) and Watson(1811). The general wrench fault nature of themineral veins was established later, but thestructural history of the Peak District drew littleearly attention until Fearnsides’ (1933) astuteobservations. From the fault pattern, he deduced thepossibility that the Peak District limestones hadbeen deposited on a block of buried Precambrian(Charnian) rocks and that this had been pushednorthwestwards so that folds in the Millstone Gritcountry were bent round it, as around the prow of aship. Fearnsides’ compilation, however, combineddifferent phases and types of folds and faults asthough one single episode of tectonic movement wasresponsible.

The nature of the pre-Carboniferous basementbelow the limestone massif remained unknown until

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Fig. 14. Sketch-map of the distribution of glacial deposits, erractic boulders and suggested lines of ice flow (from Burek, 1977).

the Woodale borehole demonstrated a volcanicfoundation only 273m down (Cope, 1949; 1973).The age of these volcanics is still uncertain. Cope(1979) reported a K/Ar date of 382±6Ma, i.e.Devonian, though this may reflect a Caledonianoverprint on Precambrian (Charnian) or Ordovicianvolcanics (Webb and Brown, 1989). In contrast, thedeep borehole at Eyam (Dunham, 1973) provedbasement at more than 1600m, composed ofOrdovician pelites. This indicated that the basementwas not a northerly extension of the Precambrianrocks of Charnwood Forest. The thick sequence ofcarbonates in this borehole threw some doubt on theburied massif concept. No boreholes in the adjacentdeep basins have proved basement. A borehole atCauldon Low in the Weaver Hills of Staffordshirepenetrated 170m of early Dinantian and possiblylate Devonian sandstones beneath the carbonates(Aitkenhead and Chisholm, 1982). The boreholeterminated at a depth of 535m, probably not farabove the basement.

Geophysical studies of the sub-Carboniferousbasement (Maroof, 1976; Rogers, 1983; Colmanet al. in Plant and Jones, 1989) suggested that thebasement is faulted and that the carbonates aredraped over tilted fault blocks, thereby covering aseries of half-grabens. The positions, trends,directions and amounts of throw on these buriedfaults remain controversial, with the faultsdownthrowing west according to Miller andGrayson (1982) or northeast according to Smithet al. (1985). Gutteridge (1987) agreed with thelatter but proposed a rather more complex pattern oflargely concealed listric faults (Fig. 15). The patternof blocks and half-grabens was discussed further byPlant and Jones (1989). Some of the bounding faultsappear to have become inactive during Dinantiantimes so that they have little or no expression in thehigher beds. Others were reactivated as wrenchfaults by later movements and may also have beenmineralized. Buried faults around the Derbyshireblock comparable with the Craven Faults boundingthe Askrigg Block to the north have not yet beendemonstrated, though Gutteridge (1991) suggestedthat such basement faults outlined the northern endof the limestone massif. The results of oil companyvibroseis traverses in the 1980s have largelyremained confidential though may ultimately yield asolution if they are ever released into the publicdomain.

The Derbyshire block thus appears to be a localuplift within a much wider South Pennine basinwhich suffered inversion as a result of the Variscancompression at the end of the Carboniferous.

Within the orefield, the major veins or rakes arecharacterized by lateral movement and Firman’s(1977) intriguingly titled paper on “Wrenches andOres, the Rake’s Progress” suggested howmineralized faults might have been propagated.However, analysis of mineral vein patterns indicatesthat the stress field changed intermittently throughmiddle and late Carboniferous times, with both

compressional and extensional phases operatingwith varying orientation (Fig. 16). These stresspatterns evolved during episodic mineralizationmainly in late Carboniferous times (Quirk, 1986;1993).

The structure of the orefield was related to a muchwider study of metallogenesis in Eastern England byPlant and Jones (1989). They extended the conceptof the Widmerpool and Edale Gulfs bounding theDerbyshire Block, first proposed by Falcon andKent (1960), to suggest that there were other blocksand basins beneath the East Midlands. Any or all ofthese basins could have held the Carboniferousmudstones that yielded the metals, fluorine, bariumand sulphur ions necessary for mineralization duringdiagenesis and could thus represent a buriedequivalent of the South Pennine Orefield.

The relationship of the different types of faultpatterns in the White Peak, the adjoining MillstoneGrit country and the coalfields to a history ofchanging stress regimes still awaits full analysis.

The burial history of the Peak District has givenrise to some debate. Though formerly portrayed onsome palaeogeographic maps as a series of islands,the South Pennines are now thought to have beencovered by Jurassic and Cretaceous strata (Copeet al., 1992), before being denuded again in Tertiarytimes.Mineral Deposits and Mineralisation. Thegalena in the mineral veins of the Peak District (alsoknown as the South Pennine Orefield) attractedattention from prehistoric times but its origin wasconsidered a matter of divine provenance: indeedtithes were once claimed on the basis that oresregenerated in the same way as crops grew on thesurface. The lead miners used elementary principlesof geology as early as the 16th century in predictingthe strata which would be penetrated in shafts anddrainage levels (Rieuwerts, 1984) (Fig. 1). However,little appeared in print until the end of the 18thcentury when brief ideas on ore genesis were putforward. Whitehurst (1778) and Farey (1811) bothargued that the ores had been concentrated fromsurrounding rocks, i.e. by some form of lateralsecretion. White Watson elaborated on this a little inan unpublished lecture sheet, advocating origin ofthe mineral veins by volcanic effects.

After these early comments there was little writtenon ore genesis until the early 20th century when aconsensus seemed to regard the Peak Districtmineral veins as being comparable with the Cornishveins and therefore fed from a concealed granite.

Mineral veins were long categorized by leadminers into four types: rakes (major fracture fills),scrins (minor fracture fills), flats (along thebedding), and pipes (cavity linings) (Fig. 17). Themineral veins themselves were catalogued by Farey(1811) with notes on their mineral content and onthe stratigraphy of the host rocks, such as 1st lime,2nd lime etc (Fig. 3). The early Geological SurveyMemoirs (Green et al., 1869, 1887) added some

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Fig. 15. Different interpretations of the basement structure beneath the Peak District:a. single tilt-block and half-graben with a major fault system throwing down to the west (after Miller and Grayson, 1982);b. two tilt-blocks and half-grabens with faults throwing down to the northeast (reproduced with permission from Smith et al.,1985; © John Wiley & Sons Ltd.).c. three tilt-blocks with half-grabens bounded by listric fault systems (reproduced with permission from Gutteridge 1987; © JohnWiley & Sons, Ltd.).

(a)

(b)

(c)

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Fig. 16. Outline maps of the changing stress fields affecting the Peak District mineral deposits (after Quirk, 1993):1. Intra-Dinantian NE-SW extension results in NW-SE faults above basement structures.2. End-Dinantian: stress field rotates anticlockwise resulting in dextral wrench faults.3. Early Namurian: stress field continues to rotate with some uplift and erosion, and the development of NNW-SSE faults.4. Late Carboniferous: thermal subsidence with maximum extension NW-SE resulting in faulting along the same trend.

information on both individual mines and onproduction but said little on ore genesis. TheInspector of Mines, A. H. Stokes, provided acomprehensive survey of mineral deposits ofeconomic potential (Stokes, 1879) and a map of theveins with an account of the history of mining and ofthe associated legal system (Stokes, 1880-83).However, he was writing during the declining yearsof the lead mining industry and it was not until theearly 20th century that interest was renewed owingto the rise of the fluorspar industry (Wedd andDrabble, 1908). World War I brought newinvestigations of resources needed for the war effortand the rebuilding of industry afterwards. TheGeological Survey published Special Reports onlead and zinc (Carruthers and Strahan, 1923),copper (Dewey and Eastwood, 1915), fluorspar(Carruthers and Pocock, 1916), barytes (Carrutherset al., 1915), fireclay and other refractories (Howe,1918; 1920). Though giving useful descriptions ofthe deposits, it is doubtful if these reports providedmuch stimulus to home production. None of thereports had much to say on genetic theories. WorldWar II brought a more complete survey of baryteresources (Dunham and Dines, 1945) and, later, offluorspar resources (Dunham, 1952). The fluorsparmining potential was reviewed again by Ford andIneson (1971).

While the distribution of the mineral deposits waswell-covered, little was written on the economics of

exploitation and matters such as stratigraphical andstructural relationships were left until later (Varvill,1937; Traill, 1939; Dunham and Dines, 1945;Dunham, 1952). The Pb-Zn-F-Ba veins occupy adominantly E-W wrench fault system and its off-shoots in the limestone massif. Local controls of theposition of strata-bound orebodies are afforded bytoadstone and tuff horizons with their limitedpermeability (Traill, 1939; Shirley, 1949). In spite ofa widely-held belief that there was no ore in thetoadstones, Walters and Ineson (1980) were able tolist many such occurrences. The dominant mineralswere shown to be zoned with fluorspar common inthe east, baryte in the centre and calcite in the west(Dunham, 1952; Mueller, 1954a). Subsequentresearch (Firman, 1977; Quirk, 1986, 1993) hasshown the distribution of gangue minerals to beconsiderably more complex owing to episodic,sometimes overlapping, phases of mineralization.

A summary map of the veins was compiled byQuirk (1993) (Fig. 18) as part of an analysis of thegenesis of the orefield (Fig. 19). An accompanyinganotated catalogue of nearly a hundred minerals wascompiled by Ford et al. (1993).

A small, separate orefield dominated by copperminerals occurs at Ecton in the Manifold Valley andwas worked as far back as Bronze Age times. Hostedin folded basinal limestones, the ore-pipes arevertical bodies said to be formed at the intersections



Fig. 17. Block diagram of the types of mineral vein in the Peak District: two rakes (one brecciated) have scrins branching fromthem: two flats underlie volcanic horizons: a pair of strata-bound pipe veins are cavities lined with minerals.

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Fig. 18. Sketch-map of the principal mineral veins of the Peak District (from Quirk, 1993).

of N-S and E-W veins (Critchley, 1979) thoughthese are difficult to delineate. On the basis of fluidinclusion studies, Masheder and Rankin (1988)argued that the ores at Ecton had been derived fromfluids expelled from the Cheshire Basin, in contrastwith the rest of the South Pennine orefield, whichhad been sourced from the east.

A unique fluorite-baryte deposit alongside DirtlowRake, south of Castleton, was found to be hosted ina pre-Namurian palaeokarstic collapse structure(Butcher and Hedges, 1987).

Unusual pervasive mineralization was found in theonly areas where Triassic sediments rested directlyon Carboniferous Limestone, at Snelston and atLimestone Hill, near Ashbourne (Cornwell et al.,1995). Although some mining of both lead andcopper occurred the deposits were only of limitedextent.

Dolomitization has affected the higher parts of thelimestone sequence (Asbian-Brigantian) over abouta quarter of the limestone outcrop (Parsons, 19

Documents

14...Laurie Whitaker from Shropshire, with an illustrated account of a trip to Clee Hill with the Shropshire Geological Society, while the 12-16 prize went to “The Palaeontology