GEOLOGICA BALCANICA, 26. 4, Sofia, Decemb. 1996, p. 41-49

Early Carboniferous miospores from Novachene Borehole, Central North Bulgaria

Tatyana Dimitrova

Geological Institute, Bulgarian Academy of Sciences, 1 J/3 Sofia, Bulgaria

'S ubmitted: 04.12.1995; accepted for publication: 29.02.1996)

T. /JuMumposa- PaHHeKap6oHcKue Muocnopbl u3 cKsa­:JK:UHbl Hosa'leHe, /.(eHmpaAbHall 'lacmb CesepHou IioA­M puu. B cTaTbe npe,AcTauneHbl pe3ynbT8Tbl nanHHono­rH'IeCKHX HCCne,AOBaHHH K86pOHCKHX CC.AHMeHTOB HJ cnalKHHbJ Houa'feHe. Bo3paCTb onpe.neneHa MHocnopa­MH - C TypHeHCICOfO B03paCTa no HHlKHe- Cpe,AHeBH3eH-

I:OMy uo3pacry. MHKpo$nopa BKnJO'faeT TaKCOHbl: Re­tispora lepidophyta, Verrucosisporites nitidus, Schopfites daviger. Raistrickia clavata, Crassispora trichera, Diato­mozonotriletes saetosus H Lycospora pussila.

Abstract. The paper presents the results of palynostrati­graphic studies of Carboniferous rocks from Novachene Borehole. The age determination is based on miospore ranges from the Upper Tournaisian to the lower-middle part of the Visean. The identified microflora includes the following taxa: Retispora lepidophyta, Verrucosisporite nitidus, Schopfites claviger, Raistrickia clavata, Crassispo­ra trichera, Diatomozonotriletes saetosus and Lycospora pussila. The sediments from Novachene contain spores attributable to the part of Biozones PL, PC, CM, PU (Westeuropean subdivision).

Dimitrova, T. 1996. Early Carboniferous miospores from Novachene Borehole, Central North Bulgaria.- Geologica Bale. , 26, 4;

Key words: Early Carboniferous; miospores; Central North Bulgaria

Introduction

Novachene Borehole was drilled in 1987. The project involves the search of oil and gas in the Moesian Platform of North Bulgaria (Fig. I). At depth of 3418 m the deepdrilling penetrates terrigenous coal-bearing rocks and ends at 4000 m. The borehole provides for the first time the possibility for investigation of the coal sediments outside the Dobrudja Coal Basin. All data avai­lable about the lithology, the coal substance and the stratigraphy of the Novachene Bore­hole are compiled in the article of Nikolov (HHKOJJOB et al., 1990). The sediments contain considerable amounts of pyroclastic material and in some intervals the rocks grade into san­dstones, tuff-sandstones, tufT-shales and siltsto­nes. The coal is mainly claroduritic, durocla­ritic or duritic. The fossil macroflora found in the borehole show that the sediments within the interval3614-3616 mare of Late Visean- Earli-

6

est Namurian age and those within the interval 3617-3706 m correspond to the middle-upper part of the Visean (6blswesa et al.,1990). Dimi­trova (1993) reported about a miospore assem­blage recovered from a number of samples from Novachene that was identified as Middle Visean. Due to the lack of material available for laboratory treatment to the present moment, the interpretation of the data needs to be fur­ther specified and completed. The present study was compiled after sampling additional rock material from the fifth core-interval (Fig. 1 ), as well as from levels beneath it.

The results presented in the article are gathe­red from the data obtained from samples of core intervals and the coreless interval at 3450.00-3645.00 m.

The determined miospore associations from the Novachene Borehole submit a question for discussion about the data published in the above mentioned article by Nikolov concerning

41

A. COre interval II

6

7 8 9

B. COle Interval V

+0

+0 +0

Fig. I . Location ofNovachene Borehole and core intervals: I - sandstones; 2 - argillite; 3 - siltstones; 4 - coal seams; 5 - fossil macroflora; 6 - tectonic zone; 7 -miospore samples

the established age and the time correlation with Irechek and Mogiliste Formation from the Dobrudja Coal Basin.

Miospore analysis

The miospore assemblages were recovered from 16 out of 17 macerated samples. The spo­res are preserved to various degrees and most of them are easily determinable. In view of the fact that materials of such a presumed age were ob­served and determined for the first time on the territory of Bulgaria, the author of the present article has used as a main source of reference some publications about miospore associations of a similar age by Playford (1962, 1978), Ut­ting et al. (1989), Higgs et al., (1988), Clayton (1971), Sullivan (1968), Byvcheva and Umnova (1992), Turner et al.(l995).

The biggest part of the studied samples be­longs to the second and fifth core-intervals (Fig. 1).

The oldest Carboniferous sediments were recovered at 3645 m. This sample is from a co­reless interval and it consists of argiJlites. The type of the miospore association is determined mainly by the presence of the following species: Retusotriletes cf. planus., Heterotriletes sp., Ver­rucosisporites nitidus, Verrucisporites bul/iferus, Retispora /epidophyta, Tumu/ispora cf. raritu­berculata, Auroraspora macra, Corbu/ispora cancel/ata, Knoxisporites literatus, Grandispora sp., Densosporites spp., Raistrickia corynoges. Two specimens of Lophotriletes cristifer occur. This species does not occur in the overlying se-

42

diments. Characteristic only of this assemblage is the presence of Tumulispora and Retispora lepidophyta.

Eight of the samples belong to the fifth core­interval: 3614.00 m; 3614.80 m; 3615.40 m; 3616.50 m; 3617.50 m; 3619.00 m; 3619.30 m; 3620.00 m.

The biggest variety of species is registered in the assemblages obtained from samples from 3619.00 and 3619.30 m.

The miospore association is characterised by the presence of the following species: Aurora­spora macra, Diatomozonotriletes saetosus, Ver­rucosisporites nitidus and Knoxisporites litera­Ius. As a part of the assemblage occur also Raistrickia corynoges, Spelaeotriletes pretiosus, Corbu/ispora cancellata, Crassispora trichera and Densosporites spp. Only at 3619. 00 m and 3620.00 m can be found Raistrickia clavata to­gether with some common representatives of the genus Convolutispora. To the same core-in­terval belong also the samples from 3615.50 and 3617.50 m. The dominant taxa are: Con­volutispora usitata, C. labiata, C. vermiformis, Knoxisporites literatus and Spelaeotriletes pre­tiosus. A peculiarity is the increased quantity of Schopfites claviger (14 specimens) and Stenozo­notriletes coronatus. Only in these samples single representatives of Dictyotriletes cf. sub­marginatus and Murospora intorta occur.

In the fourth core-interval there are two samples: 3552.00 and 3552.10 m. Both samples were macerated together due to the lack of rock material. This miospore assemblage could be distinguished from the other samples by the common occurrence of Retialetes sp. and Diatomozonotriletes saetosus. Only in this asso­ciation can be found many specimens of the taxa Monilospora, Euryzonotriletes sp., Trema­tozonotriletes variabi/is, Reticu/atisporites pelta­tus, Densosporites anulatus, Convolutispora /a­biata, C. cerebra, Densosporites anulatus, Cra­ssizonotriletes canaliculatus, Knoxisporites cin­ctus, Apiculiretusispora multiseta, Trilobozonot­riletes incisotrilobus, Waltzispora sp. The mios­pore assemblage obtained from 3550 m is from coreless interval and comprises the following species: Trilobozonotriletes incisotrilobus, Den­sosporites anulatus, Knoxisporites literatus, K. rotatus, Crassispora trichera, Convolutispora cf. circumvalata, C. labiata, Retialetes radforthii, Lophotri/etes sp., Tetraporina sp., Waltzispora planiangulata, Leiotriletes ornatus, Murospora sub/obata, M. margodentata.

From the third core-interval, two samples are examined. At 3501 m occur single speci­mens of Waltzispora planiangulata, Grandispo­ra echinata and Convolutispora cf. circumvala­ta. The species Crassispora trichera and Schop-

foes claviger continue to occur in this miospore assemblage. The appearance of Lycospora is

cific for this assemblage and distinguishes it ~ m the others. Very abundant in species is the sample recovered from 3496.70 m. The variety

miospore assemblages is determined by the esence of the following taxa: Densosporites

ariomarginatus, D. variabilis, Monilospora triun­gensis, Anapiculatisporites concinus, Convoluti­IpOra cerebra, C. mellita, Calamospora spp., Ve­rrucosisporites nitidus, Reticulatisporites cance-

. Lophotriletes densus, Stenozonotriletes per­f oratus, Spinozonotriletes uncatus, Densosporites

., Acanthotriletes sp., Punctatisporites punctatus, !Jurospora spp., Triquitrites grandis, Leiotriletes ornatus. The species Schopfites claviger is absent ~ m this assemblage.

In the second core-interval the two examined samples from 3460.50 m and 3465.00 m border

n tectonic zones which explains the presence of numerous torn plant remainders. The taxa :ound are a repetition of a part of the previous

·o assemblages: Densosporites spp., Triqui­t:riles grandis, Leiotriletes tumidus, Punctatispo-

. es glaber, P. punctatus, Convolutispora spp. ~ew for. this miospore association is the appea­rance of the species Raistrickia nigra and Cras­nspora aculeata. There are also single repre­sentatives of Lycospora pusilla.

Immediately above the second core-interval, e sample from 3450 m, represents a restored ·as pore assemblage, including the species

T ricidarisporites balteolus, Schulzospora cf. ampiloptera, Chaetosphaerites spp., Lycospora

pusilla, Raistrickia nigra, Convolutispora plani­·uricata, Rotaspora spp. The genus Tripartites

· completely absent from this assemblage.

Palynostratigraphy

ln the sediments of the Novachene Borehole ere found stratigraphic levels from the

Moesian Plarform unstudied until now. The only publication that shows the presence of the Lower Carboniferous out of the boundaires of the Dobrudja Coal Basin belongs to CnacoB ( 976). His data were obtained from Gomo­tartsi Borehole through a conodont analysis. To

e present moment, on the territory of Bulga-. a, well studied are only the miospore ass em­lages from Carboniferous sediments from the

Dobrudja Coal Basin (Late Visean - West­phalian D). The taxonomical content of the miospore assemblages from Novachene can be compared only with the results from Konare and Belgun Formations (Dimitrova, 1993). Comparisons and the correlations are possible only in the interval 3450-3550 m (Fig. 2) from

the Novachene Borehole. The biggest part of the common species compose the content of sample 3450 m: Raistrickia nigra, Lycospora pusilla, Schulzospora sp. and Rotaspora sp.

The common species from the second core­interval are similar to some miospores from Konare and Belgun Formations (Dobrudja Basin): Leiotriletes tumidus, Punctatisporites glaber, Densosporites anulatus, Convolutispora labiata, C. cerebra, Raistrickia nigra. This assemblage from the Dobrudja Coal Basin was proved to be of Late Visean age (Dimitrova, 1993). The results are comparable to the spore content from the second core-interval from Novachene.

All the other levels form the third to the fifth core-intervals and the samples from careless intervals cannot be correlated with the palyno­logical data from the Dobrudja Basin.

The taxonomical peculiarity of the species (Pis. I, II) determines the stratigraphical posi­tion of the miospore assemblages from the Novachene Borehole and makes them com­parable to the general divisions from Western Europe (Clayton et al., 1917) and Western Europe and the Russian Platform (Owens et al., 1978). Well studied are the ranges of some of the following index-species: Verrucosisporites nitidus, Raistrickia corynoges, R. clavata, Spe­laeotriletes pretiosus, Crassispora trychera, Schopfites claviger, Lycospora sp., Retispora lepidophyta. The species listed above are impo­rtant for the associations .of the Carboniferous biozones CM, PU from the Westeuropean sub­division (Clayton et al., 1977). The established age is Tn 3/ V 1-2··

According to the miospore analysis, the boundary between Late Devonian and Early Carboniferous can be defined between the two zones LN and PC introduced by Loboziak (in Loboziak et al., 1994) which also includes the appearance of Schopfites cf. claviger and Crassispora trichera.

Some species from the fourth core-interval in the Novachene Borehole are similar to to the Middle Visean miospore associations from the Russian Platform (liblawesa et al., 1985): Crassizonotriletes variabilis, C. canaliculatus, C. macroduplicatus, Euryzonotriletes sp., as well as Densosporites .

As a result of the correlation between the miospore assemblages from Poland and Great Britain, Turnau (in Clayton and Turnau, 1990) established the following species as typical for the zone CL for West Pomerania miospore zonation: Tumulispora rarituberculata, Raist­rickia clavata, R. corynoges, Knoxisporites lite­ratus, Schopfites claviger. The established age is

43

PLATE I

Early Carboniferous miospores from Novachene borehole. All figures x 700. I. Triquitrites cf. grandis; depth 3460.50 m. 2. Anapiculatisporites concinnus Playford; depth 3496.70 m. 3. Triquitrites marginatus Hoffmeister, Staplin and Malloy; depth 3645.00 m. 4. Schopfites claviger Sullivan; depth 3617.00 m. 5. Crassispora cf. trichera Neves and Joannides; depth 3619.00 m. 6. Convolutispora vermiformis Huques and Playford; depth 3619.30 m. 1.Crassispora trichera Neves and Joannides; depth 3619.00 m. 8. Murospora intorta (Waltz) Playford; depth 3617.50m. 9. Reticulatisporites cancellatus (Waltz) Playford; depth 3496.70 m. I 0. Convolutispora planimuricata Butterworth and Spinner; depth 3450.00 m II. Leiotriletes ornatus lchchenko; depth 3496.70 m. 12. Punctatisporites glaber (Naumova) Playford; 3696.70 m. 13. Convolutispora usitata Playford; depth 3696.70 m. 14. Diatomozonotriletes saetosus (Hacquebard and Bars) Huques and Playford; depth 3619.30 m. I5. Verrucosisporites nitidus Playford; depth 3645.00 m. 16. Crassizonotriletes canaliculatus (Playford) Byvscheva; depth 3552.10 m. I 7. Knoxisporites litera/us (Waltz) Playford; depth 36I 9.00 m. 18. Convolutispora labiata Playford; depth 3615.50 m.

PLATE II

Early Carboniferous miospores from Novachene borehole. All figures x 700.

1. Retialetes sp.; depth 3552.00 m. 2. Raistrickia clavata (Hacquebard) Playford; depth 3620.00 m. 3. Retusotriletes sp.; 3645.00 m. 4. Monilospora sp.; depth 3552.00 m. 5. 7 Grandispora sp.; depth 3501 .00 m. 6. Rugospora sp.; 3645.00 m. 7. Vallatisporites verrucosus Hacquebard; depth 3617.50 m. 8. Concentricisporites ? concentricus Byvscheva; depth 3645.00 m. 9. Heterotriletes sp. I McGregor and Playford; depth 3645.00 m. I 0. Tumulispora cf. rarituberculata (Luber) Playford; depth 3645.00 m. 11. Retispora lepidophyta (Kedo) Playford; depth 3645.00 m. 12. Lophotriletes cristifer (Luber) Kedo; depth 3645.00 m. 13. Tetraporina sp.; depth 3552.00 m. 14. Lophotriletes sp.; depth 3552.30 m. IS. Monilospora triungensis Playford; depth 3552.00 m. 16. Corbulispora cancellata (Waltz) Bharadwaj and Vencatachala; depth 3645.00 m.

44

P LATE I

11 8

45

46

L'f

:n 1!11 ~

a [ e: ~ 5: c:: -s· ::I 0 .... :T n 9

~· ri

E

BOREHOLE NOVACHENE

< ~ - - ~(") - - 0 0 f- - ..., ..., < CD

QOJynot_o_gtcat pro_ft e 0 ~

~ e ~ 00 ~~ <a~ <a .a

' I OD (;) (/)

I I

~ 0 w w w w -8 0) 0) (11 (11 ~ ~ 0 (11 0 (11 -(11 0 0 0 0 '::1'

3

• T. cf. rarituberculata

• R. lepidophyta

• V. nitidus

.. R. clavata

••• S. claviger

..... c. trychera ~ .. C. cf. circumvalata -· 0

- K. literatus VI

"0

Crassizonotriletes sp ..... 0 ...,

Euryzonotriletes sp. CD

T. incisotrilobus • -i 0

M. triungensis .... X 0

Murospora s p.

Lycospora pusilla

C. aculeata .-.

R. nigra . ....--. Schulzosporo sp. e---e

Rotaspora sp . ... T1-2 T3•V1-2 T3Upper + V1-2 V1-2 v3 I~ NV PC+CM CM f" PU PU NM

N 0 ;::)

Miospore_ ~~n~~- W. E_u_r- o p e -Qa y ton et al.t 1977 CD

T 2.3• In the same article Clayton assumed that the disappearance of Tumulispora from the se­diments of the British Isles determines the boundary between the zones PC and CN. All species which are included in the zonal scheme Clayton, Turnau's (1990) publication, represent a part of the miospore assemblage from the interval 3614 - 3645 m from the Novachene Borehole.

Conclusion

The miospore assemblages recovered from the majority of the examined samples (exceptions are those from the second core-interval and above the second core-interval) show the pre­sence of the species Verrucosisporites nitidus, which tentatively determines the statigraphical importance of the miospore assemblage. The morphological discussion about the description of the index-species and its synonymy, based mainly on the size of the basal diameter of verrucae, was given by Turnau et al.(1993). The authors have used material from different Car­boniferous localities: West Pomerania (Po­land), LL-CM Biozones; from Ireland, LN Biozone; from Russian Platform, Belarus and Russia, LE and LN Biozones.

The first appearance of the species V. nitidus was identified by Playford (1964) and was related to the Tournaisian Horton Group from Eastern Canada. The species V. nitidus is consi­dered in Northwest Europe to be an important zonal species.

The information about the taxonomy and the stratigraphical significance of the species V. nitidus reveals that its presence in the miospore assemblages from the Novachene Borehole is extremely important for the correlation of the sediments from this borehole with other analo­gical localities in Europe. The age of the mio­spore assemblages from different core and co­relies intervals is determined by species with considerable staratigraphical importance, such as: Tumulispora cf. rarituberculata (3645 m); Raistrickia clavata (3619- 3620m); Schopfites claviger (3501 -3617,50m); Lycospora pusilla (3465 - 3501 m). The taxa listed above charac­terise the biozones VI, PC, CM and PU from the generalised zonal scheme for Western Eu­rope (Clayton et al., 1977).

From the analysis of the miospore associa­tions and the stratigraphical distribution of the single species the following conclusions can be made:

1. The age of the sediments from Novachene in the interval 3501-3645 m, including the dis­tribution of the species V. nitidus, was establi­shed as Tn2{fn3 - Vl-2.

48

2. The appearance of the taxa Schulzospora and Rotaspora in the sample from 3645 m gives also information about the Visean age in the Novachene Borehole. A peculiarity is the com­plete absence of the genus Tripartites.

3. The sediments in the interval 3465-3550 m can be correlated with parts of the Belgun and Irechek Formations (Dobrudja Coal Basin).

4. For the first time on the territory of Bul­garia were registered miospore assemblages from Early Carboniferous age.

5. It remains an open question whether there was a spatial relation between the Novachene Borehole and the Dorudja Coal Basin during the Visean.

APPENDIX

List of taxa recorded In the present study Apiculiretusispora multiseta (Luber) Butterworth and

Spinner, 1967 Anapiculatisporites concinnus Playford, 1962 Calamospora sp. Convolutispora planimuricata Butterworth and Spinner,

1967 C. labiata Playford, 1962 C. cerebra Butterworth and Williams, 1958 C. cf. circumvalata C. mel/ita Hoffmeister et al., 1955 C. vermiformis Hughes and Playford, 1961 Concentricisporites ? concentricus Byvscheva, 1976 C. usitata Playford, 1962 Corbulispora cancellata (Waltz) Bharadwaj and

Vencatachala, 1961 Crassispora trichera Neves and Joannides, 1974 Crassispora aculeata Neville, 1968 Crassizonotriletes canaliculatus (Playford) Byvscheva,

1985 C. cf. macroduplicatus (Naumova) Byvscheva, 1985 Cincturazonotriletes literatus (Waltz) Hasquebard and

Barss, 1957 Densosporites variomarginatus Playford, 1963 D. anulatus (Loose) Smith and Butterworth, 1967 D. variabilis (Waltz) Byvscheva, 1980 Diatomozonotriletes saetosus (Hacquebard and Barss)

Hughes and Playford, 1961 Dictyotriletes cf. submarginatus Playford, 1962 Euryzonotriletes sp. Grandispora echinata Hasquebard, 1957 Grandivpara sp. Heterotriletes sp.l Me Gregor and Playford, 1992 Knoxisporites literatus (Waltz) Playford, 1963 K. cinctus (Waltz) Butterworth and Williams, 1958 K.noxisporites sp. Leiotriletes tumidus Butterworth and Wiliams, 1958 L. ornatus lchchenko, 1956 Lophotriletes sp. Lophotriletes cristifer (Luber) Kedo, 1966 L. densus Love, 1960 Lycospora pusilla (Ibrahim) Somers, 1971 Monilospora triungensis Playford, 1963 Murospora intorta (Waltz) Playford, 1962 M . sublobata Beju, 1970 M. margodentata, Beju, 1970

Punctatisporites glaber (Naumova) Playford, 1962 Retispora lepidophyta (Kedo) Playford, 1976 Retusotriletes sp. Raistrickia corynoges Sullivan, 1968 R. clavata (Hasquebard) Playford, 1962 R. nigra Love, 1960 Reticulatisporites cancellatus (Waltz) Playford, 1962 Retialetes radforthii Staplin, 1960 Rotaspora sp. Rugospora radiata (Kedo) Byvscheva, 1985 Schulzospora cf. campiloptera Schopfites claviger Sullivan, 1964 Spelaeotriletes pretiosus (Playford) Neves and Belt, 1971 Stenozonotrilctes corona/us Sullivan and Marshall, 1960 Tetraporina sp. Trilobozonotroletes sp. T. incisotrilobus Naumova ex Ishchenko, 1956 Triquitrites marginatus Hoffmeister et al., 1955 Tricidar:isporites balteolus Sullivan and Marshall, 1966 Tumulispora cf. rarituberculata Verrucosisporites cf. V. nitidus Playford, 1964 Vallatisporites verrucosus Hacquebard, 1957 Waltzispora sp. W. planiangulata Sullivan, 1957

References

Byvcheva, T.V., Umnova, N.I. 1992. Palynological chara­cteristics of the Lower part of the Carboniferous of the Central region of the Russian platform. - Ann. Soc. geol. Belgique, 115, 2; 519-529.

Clayton, G. 1971. A Lower Carboniferous miospore as­semblage from the Califerous Sandstone Measures of the Cockburuspath region of Eastern Scotland. -Pollen Spores, 12; 577-600.

Clayton, G., Coquel, J., Doubinger, J., Gueinn, K.J., Loboziak, S., Owens, B., Streel, M. 1977. Carboni­ferous miospores of Western Europe: illustration and zonation.- Meded Rijks Geol. Dienst., 29; 1-17.

Clayton, G. and Tum au, E. 1990. Correlation of the Tou­maisian miospore zonations of Poland and the British Isles. -Ann. Soc. Geol. Pol .• 60, 45.

Dimitrova, T. 1993. Palynostratigraphy of the Irechek Formation (Upper Visean-Lower Nam·urian) from Dobrudza Coal Basin, North-East Bulgaria.- Geolo­gica Bale., 23, 4; 55-63.

7

Dimitrova, T. 1993. Carboniferous miospores from R-1 Novachene well section (Central North Bulgaria). -Geologica Bale., 23, 6; 60.

Higgs, K., Clayton, G. and Keegan, J. 1988. Stratigraphic and systematic palynology of the Tournaisian rocks of Ireland. - Geol. Jr. Spec. Pap. 7; 1-93.

Loboziak, S., Street, M., Dusar, M., Boulvain, F. and G. De Geyter. 1994. Late Devonian - Early Carboniferos miospores from the Menen Borehole, Namur Synclinorium, Belgium. - Rev. Palaeobot. Palynol., 80; 55-63.

Owens, B .• Loboziak, S. and Teteriuk, V.K. 1978. Palyno­logical subdivision of the Dinantian to Westphalian deposits of North West Europe and the Donetz Basin

· of the U.S.S.R. - Palynology, 2; 69-91 . Playford, G . 1962. Lower Carboniferous microfloras of

Spitsbergen. Part I. - Palaeontology,5; 550-618. Playford, G., 1964. Miospores from the Mississippian

Horton Group, Eastern Canada. - Bull. GeoL Surv. Can .• 107; 1-47.

Playford G. 1978. Lower Carboniferous spores from the Ducabrook Formation, Drummond Basin, Queens­land.- Palaeontographica B.,167; 105-160.

Sullivan, H. J. 1968. A Toumaisian spore flora from the Cementstone Group of Ayrshire, Scotland. - Palae­ontology, II; 116-131.

Turnau, E., Avchimovitsh, V.I., Byvsheva, T.V., Clayton, G., Higgs, K. T. and B. Owens. 1994. Taxonomy and stratigraphical distribution of Verrucosisporites nitidus Playford, 1964 and related species. - Rev. Palaeobot. Palynol., 81; 289-295.

Turner, N., Spinner, E., Doming, K.J. 1995. A palyno­logical study of the Lower Carboniferous lydebrook sandstone and adjacent late Wenlock and Langsettian strata, Shropshire, England. - Rev. Palaeobot. Paly­nol .• 84; 305-329.

Utting, J., Jachowicz, M. and Jachowicz, A. 1989. A paly­nological study of the Lower Carboniferous strata (Di­nantian), from Titterstone clee, Shropshire, England. -Pollen Spores, 30; 429-459.

liblsmesa, T. 1985. Ant.~rac cnop u nbl.lrbllbl HetjJmeza3o­HOCHblX mO.IliJl rpaHep030Jl pycCKOU U mypaHCKOU 11.11um. MocKsa, He.llpa. 224 c.

HHKonos, 3., nonosa, K. nonos, A. 1990. Bl>rneHocHH ropHonaneoJoACKH ce.llHMeHTH s P-1, HosalfeHe (UeHTpanHa CesepHa liDnrapHR). - Cn. Ii'6.11Z. zeoA. d-Bo, 51, I; 38-47.

Cnacos, X. 1977. TypHeACKH KOHO.llOHTH OT cOH.llUC P-3 [oMOTapUH (CeBepo3ana,o.Ha liDnrapJUl). - llaAe­OHm. cmpamuzp. u Aumo.ll. , 6; 3-13.

49