SERVICES & FACILITIES ANNUAL REPORT - FY April 2005 to March 2006

SERVICE FUNDING AGREEMENT ESTABLISHED as S&F TERM ION MICROPROBE FACILITY

(IMF)

Contract F14/G6/40 1987 5yrs

TYPE OF SERVICE PROVIDED:

The Ion Microprobe Facility (IMF) (see http://www.geos.ed.ac.uk/facilities/ionprobe/) is the only UK facility

enabling SIMS (secondary ion mass spectrometry) analysis of a wide range of natural and synthetic materials. It

allows in-situ, high spatial resolution (5–20 µm) analysis of elements and isotopes across the whole Periodic Table, and

is ideal for studies of fine-grained and zoned Environmental and Earth Sciences materials such as minerals and fossil

skeletons. The IMF has a very strong international reputation, and has pioneered the development and application of

SIMS stable isotope analysis techniques on insulating materials (e.g. silicates, carbonates).

Two ion microprobes (Cameca ims-1270 and ims-4f) provide the analysis of a wide range of stable isotope ratios (H,

Li, B, N, C, O, S, Si), trace elements (e.g. rare-earth elements, large ion lithophile elements, high field strength

elements) and light elements (H, Li, Be, B, C, N). Depth profiles of elemental or isotopic composition can also be

obtained; this is particularly useful for diffusion studies. In general most heavy (>C) stable isotope work is done on the

ims-1270 since its analytical precisions are some 4 to 5 times higher and its counting times (with multi-collector) are

shorter than on the ims-4f. The high transmission of the ims-1270 has also permitted a geochronology service, using

U-Th-Pb isotopic dating of zircon and other U- and Th-bearing minerals, to be offered recently for first time. The ims-

4f is mainly used for multi-element, light element and light isotope (H, Li, B) analysis.

The Ion Microprobe Facility is located in the Grant Institute of Earth Science, School of Geosciences, University of

Edinburgh, where the ion microprobe (SIMS) instruments form the centre-piece of a unique and complementary suite

of world class micro-beam instruments for different types of micro-analysis. The IMF also provides access to the new

Cameca SX100 electron microprobe and analytical SEM facilities (including detectors for Energy Dispersive Analysis,

Backscattered Electron Imaging, Cathodoluminescence and Electron Backscatter Diffraction) - these may be used for

full characterisation of samples on site. Tephrochronology, involving high precision microanalysis of glasses to

permit correlation of tephra layers for relative age dating, forms an integral part of the service (see

http://www.geos.ed.ac.uk/facilities/tephra/).

Access to the Facility is by peer review via the IMF Steering Committee and is free for members of the NERC

community. Overseas users are charged at scales depending on the extent of collaboration with members of the NERC

community. Advice on analytical strategy is given. All visitors to the IMF are trained in instrument operation and in

data reduction and interpretation. This ‘hands-on’ approach for all users contributes strongly to the training of the post-

graduates and post-doctoral researchers. ANNUAL TARGETS AND PROGRESS TOWARDS THEM

The target to supply high precision oxygen isotope analysis and U-Th-Pb geochronology to the user community was

met. The total number of NSS instrument user hours of over 3100 was significantly up on previous years despite

continuing research and development on the ims-1270 to extend the analytical capabilities of this new instrument. All

users received time within deadlines set.

SCORES AT LAST REVIEW (each out of 5) Date of Last Review:

Need Uniqueness Quality of Service Quality of Science & Training Average

5.0

5.0 5.0 5.0 5.0

Staff & Status

Richard W Hinton

CAPACITY of HOST ENTITY

FUNDED by S&F

Nicola Cayzer 50% TIME

Next

Review

(January)

Contract

Ends

(31 March)

60% David Steele 50% TIME 2007 2008

FINANCIAL DETAILS: CURRENT FY

Unit Cost £k Tital resource

allocation £k Unit 1 Unit 2 Unit 3

Capital

Expend £k

Income

£k

Full cash

cost £k

0.125 per hour 0.250 per session 0 £175.5

FINANCIAL COMMITMENT (by year until end of current agreement)

2005-06 165 2006-07 245 2007-08 267 2008-09 270 2009/2010

STEERING COMMITTEE Independent Members Meetings per annum Other S&F Overseen

IMF 6 2 0

APPLICATIONS: DISTRIBUTION OF GRADES (Current FY — 2005/06) Data for the Ion Microprobe Facility (IMF) and

Tephrochronology analytical unit (TAU) given separately (all TAU numbers preceded by a +)

αααα5 αααα4 αααα3 αααα2 αααα1 ββββ R*/Pilot Reject

NERC Grant projects 6

Other academic 3 4 1 2 2

Students 1 1

Pilot

TOTAL 3 10 2 2

APPLICATIONS: DISTRIBUTION OF GRADES (per annum average previous 3 years —21002/03 – 2004/05

αααα5 αααα4 αααα3 αααα2 αααα1 ββββ R*/Pilot Reject

NERC Grant projects .7+.3 2.3 .7

Other Academic 1.7+.3 3.7+.7 .7 1 .3 1 1

Students .3 2.7+4 2.7 .3

Pilot 2

TOTAL 2.7+.7 8.7+4.7 4 1.3 0.3 3 1

PROJECTS COMPLETED (Current FY)

αααα5 αααα4 αααα3 αααα2 αααα1 ββββ R*/Pilot

NERC Grant projects 2 5

Other Academic 2

Students 2

Pilot

USER PROFILE (current FY) *Combined non-Directed and Directed

Infrastructure PAYG

Student Student Grand

Total Supplement to NERC

Grant * Total NERC

NERC

RC Other

NERC

Grant* Total NERC

NERC

C/S Other

26+7

7+1 7+5 4+2

12+2

USER PROFILE (per annum average previous 3 years) *Combined non-Directed and Directed

Infrastructure PAYG

Student Student Grand

Total Supplement to NERC

Grant * Total NERC

NERC

RC Other

NERC

Grant* Total NERC

NERC

C/S Other

28.7+7.4 3.7 8.3+4.7 5+4 11.7+2.7

USER PROFILE (current FY)

Academic NERC RC NERC Fellows PhD Commercial

17 2 7

USER PROFILE (per annum average previous 3 years)

Academic NERC RC NERC Fellows PhD Commercial

13.3+2.7 0.3 0.3 9.3+5.3

OUTPUT & PERFORMANCE MEASURES (current FY)

Publications (by science area & type)

SBA ES MS AS TFS EO Polar Grand Total Refereed Non-Ref/ Conf Proc PhD Theses

100 45

24 17 4

Distribution of Projects (by science areas)

SBA ES MS AS TFS EO Polar

77% 23%

OUTPUT & PERFORMANCE MEASURES (per annum average previous 3 years)

Publications (by science area & type)

SBA ES MS AS TFS EO Polar Grand Total Refereed Non-Ref/ Conf Proc PhD Theses

47 47 26

16.7 4.3

Distribution of Projects (by science areas)

SBA ES MS AS TFS EO Polar

80% 20%

Distribution of Projects (by NERC strategic priority)

Earth’s Life Support Systems Climate Change Sustainable Economies Underpinning Science Specific Research

30% 70%

OVERVIEW & ACTIVITIES IN FINANCIAL YEAR (2005/06):

Analytical methods for U-Th-Pb analyses of zircon have been improved with the addition of a new lens immediately after the

oxygen primary ion source. This lens has significantly increased the primary beam current available and has greatly improved

long term beam stability. 24 hour operation is now possible and continuous runs of up to 6 days have been achieved.

A high precision Nuclear-Magnetic-Resonance (NMR) probe has been installed to improve the stability of the magnetic field

control for multi-collector operation. The NMR probe has proved useful in determining the general stability of the magnet

control and in troubleshooting of the magnet control system. The analytical techniques and protocols for stable isotope

analyses of C, N and O continue to be improved as experience is gained on the new instrument. New standard materials are

continuing to be obtained and assessed in order to expand the range of minerals and isotopes which can be studied (e.g. titanite

and aragonite for oxygen). The high performance of the ims-1270 has continued with precisions for oxygen isotope analyses

down to 0.2 per mil for a 6 minute analysis. Automatic (chained) analyses have been shown to give high degree of

reproducibility in instrument tuning and also a high analytical efficiency.

Changes have been made to the configuration of the SX100 to permit analysis of a wider variety of elements without

compromising sensitivity. The changes also permit more accurate fluorine analysis of tephra and enable chemical dating

procotols to implemented. A forescatter detector has been added to the SEM to enhance the EBSD capabilities. This allows a

faster assessment of the grain and sub-grain structure within a sample allowing more efficiently targeted mapping.

SCIENCE HIGHLIGHTS (including four most impactful outputs):

Variations in the elemental composition of minerals can often be studied in great detail using physical techniques e.g.

cathodoluminesce, backscattered electron imaging etc. Sometimes intricate patterns may be observed which can then be

related to growth events, subsequent alteration etc. Isotopic variability, in contrast, has had to be inferred from a few

well placed analyses across a crystal. The new ims-1270 multicollector detection system permits a high precision C

isotope measurement to be made in 2-3 minutes. This fast analysis time has been fully utilised to generate the first

detailed carbon isotope map of a diamond. The diamond chosen was one which previously demonstrated such complex

Cl zoning (related to N abundance) that it was referred to as the ‘Picasso’ diamond (photo left). C isotope mapping has

demonstrated that the diamond is equally strongly zoned in its carbon isotope signature. The high degree of

correspondence between chemical zoning (N variability) and carbon isotopes which formed during growth has not been

removed despite the crystal sitting a high temperature and pressures for many million years.

Cathodoluminesence image (left) and Carbon isotope image (right) of SCHdiamond16 otherwise known as the ‘Picasso’

diamond. The carbon isotope complexity shows close correspondence with the CL and nitrogen element zonations Total

range shown -10 � 13

C (yellow) to -18 � 13

C (red).

The lead isotopic signature of melt inclusions from Iceland has been studied for the first time. It was shown that the

interpretation of the lead isotope data can be considerably enhanced by the addition of trace element analyses made on the

same inclusions, a procedure only possible by ion microprobe. The lead isotopic variability was surprisingly high. The

variation found in one hand specimen covered 40% of the global range observed in oceanic basalts, a greater range than

has been observed in any of the whole rock samples from the Icelandic rift zone. This variability on the micro-scale is

thought to have originated at depth, rather than due to shallow magma chamber processes, and testifies to the generation

of melt from a wide variety of sources. If the variability is deep seated, the trace element compositions can be used to

give further information on the source materials and permit the high melt production rates of Iceland volcanic sources to

be better modelled.

U/Pb

IP pit trace

element IP

pits

oxygen isotope

IP pits

SEM image of zircon. Holes in surface

represent individual ion probe (IP)

analyses.

The ages and origins of Scottish Caledonian granites are being investigated

by combining radiogenic dating, oxygen isotope and trace element

analysis of zircons. Zircon is extremely unusual in that once formed it is

difficult to destroy: it can survive high temperature processes, including

melting, and is sufficiently physically and chemically robust to survive

weathering and sedimentary processes. Thus while a population of crystals

can give information on a single igneous event, individual crystals, or indeed

small areas within a crystal, may retain evidence for earlier events. The U/Pb

age determined for the Lochnagar granite zircons was 421±4Ma. Ages for

the individual units of this granite overlap suggesting they were all intruded

over a relatively short time period. The oxygen isotope signatures

demonstrate that a crustal component is present in all samples and none have

an unmodified mantle source. The melting and assimilation of crustal rocks

was confirmed in several samples by both the presence of inherited grains

and a wide range of oxygen isotope values.

The changes which occur during the ascent of magma towards the surface have been highlighted in samples of Mount St

Helens eruptions that have occurred since the catastrophic eruption of 1980. Trace element and H2O contents on melt

inclusions have been combined with the geothermometry of the host plagioclase pressure-temperature-ascent path. Rb

was used to determine the extent of crystallisation, H2O the confining pressure (and hence depth), and the host chemistry

gave the crystallisation temperature. The results demonstrate for the first time that decompressing H2O-saturated magma

has experienced a large heating effect during crystallisation, in this case by a remarkable 80ºC, due to latent heat of

crystallisation. Significant Li enrichments gave strong evidence for the transfer of a magmatic vapour phase from deep

seated to shallow reservoirs. These results have important implications for the rheology of ascending hydrous magmas

and the style of the eruptive processes.

In the calendar year 2005 data from the facility was included in 24 papers in refereed journals including three in Earth

and Planetary Science Letters, three in Geochimica Cosmochimica Acta and three in Contributions to Mineralogy and

Petrology. One paper including oxygen isotope analyses of zircons has recently appeared in Nature.

1) Blundy J. and Cashman K. (2005) Rapid decompression-driven crystallisation recorded by melt inclusions from

Mount St. Helens volcano. Geology 33, 793-796.

2) Cavosie A.J., Valley J.W., Wilde S.A. and EIMF (2005) Magmatic �18

O in 4400-3900 Ma detritial zircons: A

record of the alteration and recycling of crust in the Early Archaen Earth Planet. Sci. Lett. 235, 663-681.

3) Corgne A., Liesbke C., Wood B.J. Rubie, D.C. and Frost D.J. (2005) Silicate perovskite-melt partitioning of trace

elements and geochemical signature of a deep perovskitic reservoir Geochim. Cosmochim. Acta 69, 485-496.

4) Kemp A.I.S., Hawkesworth C.J., Paterson B.A. and Kinny P.D. (2006) Episodic growth of the Gondwana

supercontinent from hafnium and oxygen isotopes in zircon. Nature 439, 580-583.

FUTURE DEVELOPMENTS/STRATEGIC FORWARD LOOK

A number of further improvements to the ims-1270 are planned. A new sample airlock system for the ims-1270 is

already under construction. The new airlock will permit storage of 6 samples under vacuum compared to only 2 at

present. The addition of the unique 8 sample airlock system to the ims-4f resulted in significant improvement in

analytical methods, instrument vacuum and turn around time after sample changes. It is hoped that the new ims-1270

airlock will also significantly improve analytical methods by permitting additional standards to be stored together with

more unknowns. Residual gas analysers will be added to both the new airlock and the sample chamber to permit leak

testing and better monitoring of the systems vacuum, including the effects of sample outgassing.

Improvements will continue to be made to all instruments to permit the integration of analytical techniques in the

determination of the structural, isotopic and chemical variability of individual crystals. For example several recent

projects on zircon have combined analyses using the EPMA, SEM, ims-4f and ims-1270 instruments. Improvements to

the SEM for structural and crystal orientation determination will be followed by the addition of a cold stage for the

analysis of sensitive samples. The changes to the hardware and configuration of the SX100 will permit chemical dating

protocols to be developed such that samples can be dated by both chemical and isotopic techniques. This will improve

the accuracy of both methods and extend dating to samples which are too small to be analysed by ion probe techniques.