The origin of organic matter in the Lower Silesia copper-bearing shales

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Annales S ocietatis G eologorum P oloniae (1993), vol. 63: 85 - 99 PL ISSN 0208-9068

THE ORIGIN OF ORGANIC MATTER IN LOWER SILESIAN COPPER-BEARING SHALES

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Mariusz J. Rospondek , Anna Fijałkowska & Anna Lewandowska

1 Jagiellonian University, Institute o f G eological Sciences, D epartm ent o f M ineralogy and Petrography, ul. O leandry 2a, 30-063 Kraków, Poland,

2 State G eological Institute, H oly C ross Branch, ul. Zgoda 2 1 ,2 5 -9 5 3 K ielce, Poland.

Rospondek, M. J., Fijałkowska, A. & Lewandowska, A., 1993. The origin o f organic malter in Lower Silesian copper-bearing shales. Ann. Soc. Geol. Polon., 63: 85 - 99.

A b s t r a c t : Stratified Lower Silesian copper deposits, similar to other deposits of this type, are enriched in organic matter. Microscope analyses o f this substance occurring in the examined lithofacies of copper-bearing shales indicate that this organic material consists predominantly of structureless organic debris. Recognizable organic debris (vascular bundle, wood remains and palynomorphs) occur in subordinate amounts. The estimation of chemical nature o f the quantitative

ly dominant but microscopically unidentifiable organic matter at the molecular level, was carried out using gas capillary chromatographic analysis o f the pyrolysis products o f kerogen Py(6 ICTC)- GC. Kerogen occurring in the copper-bearing shales consists o f aliphatic macromolecules (n-alkanes and n-alk-l-enes were identified among the pyrolysis products). Thus composition is characteristic for biopolymers which are highly resistant to (bio)chemical degradation occurring in algae (al- gaenan) and protective anvelopes of higher plants (subcran and cutan). However, since no such tissues were encountered microscopically, organic matter must be derived from marine algae.

The presence o f thiophene structural units in kerogen.indicates anaerobic (H2S) conditions in the sedimentous environment. When compared with other types of organic material, the structureless organic matter is enriched in metal sulphides. The sulphides are directly bound to structureless organic matter and occur as framboids. Organic matter is enveloping the sulphide concentrations. This indicates the important role of this organic malter in framboid formation by the isolation of precipitated iron sulphide phases from sedimentation environment and protection o f these sulphides from replace

ment by copper sulphides due to action of Cu-bearing solutions.

K e y w o r d s : copper-bearing shales, kerogen, Py-GC, highly aliphatic biopolymer, algaenan, framboids.

Manuscript received 10 August, 1992, accepted 8 July 1993

INTRODUCTION

T he p resent studies deal with the organic m atter occurring in the Z echstein copper-bearing shales (K upferschiefer) from the L ow er Silesian copper d e posits, SW Poland. T his G erm an term “ K upferschiefer” im plies very thin, stratified sulphide-bearing series, occurring betw een R otliegendes continental

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faciès (L ow er Perm ian) and transgressive, usually carbonate Z echslein sed i

m ents (U pper Perm ian). A detailed description o f this geological setting is presented e.g. by O szczepalski (1986).

G eochem ical studies o f organic m atter from the Sudetic M onocline w ere carried out by S aw łow icz (1991) who also reviewed earlier publications on this subject. On the other hand, Püttm ann et al. (1990) have exam ined m ainly ex tractab le organic m àtter (EO M ) from the N orth Sudetic Syncline. B oth authors are em phasizing secondary alterations, first o f all oxidation, o f o r

ganic m atter and its potential reducing role in the origin o f the deposit. H ow ever, th ese in v estig atio n s did n o t lead to the defin itiv e d e te m iin a tio n o f biological precursors o f this organic m atter, the origin o f w hich is generally considered to be sapropelic (H aranczyk, 1986).

T he aim o f this study was to identify organic rem ains from the copper- bearing shales and to determ ine the relationship betw een the occurrence of individual m acérais (organic m atter types) and the presence o f sulphides en trapped w ithin organic m atter. To solve these issue, two w eight fractions o f organic m atter, separated in heavy liquid, w ere subjected to m icroscope ex am ination in transm ittant light and the m orphology o f individual grains was studied using scanning m icroscopy (SEM ).

Since com plete identification o f organic rem ains was im possible using only the m icroscopic m ethod, seven representative sam ples w ere selected for m ore detailed investigation of kerogen type at the m olecular level. A new analytical technique, fo r this m aterial, was applied - nam ely Curie p o int p y ro lysis gas chrom atography Py(610°C )-G C (Nip, 1987). T h e identification o f the p y ro ly sis p ro d u cts w as carried o u t by m eans o f m ass sp e c tro m e try Py(610°C )-G C -M S. T h e identification o f chem ical structure at m olecular level allow ed to define biological precursors o f organic m atter occurring in copper- bearing shales.

MATERIALS

T h e m aterials studied w ere collected from the L ow er Silesian co p p er-b ear

ing beds w ithin the F ore Sudetic M onocline (Fig. 1). T he sam ples com es from accessible m ining fields o f the Rudna North (galleries N-4, N-6 and W -249) and Lubin G łówny. T h eir detailed position in the geological cross-section is presented w hen discussing lilhological characteristics o f sedim ents. B asing the choice on lithological characteristics, ten sam ples w ere selected fo r lab o r

atory exam inations, w hereby the sym bols o f those seven subjected to g eo chem ical study are underlined.

T h e geological setting o f the area in question is described in detail e.g. by N iśk iew ic z (1980) and O szczep alsk i (1986). A ccording to O szczep alsk i (1986), w hite sandstone (B s l) and the overlying copper-bearing shales ( T l) initiate the Zechstein sedim entary sequence in this area. Further upw ards,

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ORGANIC MATTER IN COOPER-BEARING SHALES

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Fig. 1 Location o f the area in vestig a ted on a sketch map o f Poland (the left hand comer) and the g e o l o g i c a l map o f th e Lower Silesia Mining D is

trict indicating the location o f the mines

copper-bearing shales pass gradually into the Zechstein lim estone (C a l). L o cally, boundary lim estone (C a lp ) appears betw een the sandstones (B s l) and copper-bearing shales (T l).

T h e follow ing lithological units can be distinguished w ithin the sam pled profiles (Fig. 2):

I - boundary dolom ite (locally lacking) - usually gray, coarse-grained, being a facial variety o f boundary lim estone (C a lp ), 0 - 20 cm thick, rep re

sented by sam ple RPn-D ol.

II - "dirtying" shale, black, structureless or, scarcely, fine-lam inated, containing the highest am ounts of organic carbon. It is from several to 50 cm thick and represented by sam ples R P n -l (N-6L R Pn-9 (N -6), R P n -l (W -249), R Pn-4 (W -249).

III - lam inated m arly shale, black or dark gray, 20 - 50 cm thick, rep re

sented by sam ples RPn-3 (N -4), L -1 5 .

IV - carbonates (a facial variety o f the Zechstein lim estone (C a l)), gray partly m arly, lam inated in the bottom part, represented by sam ples R Pn-4 (N -4). R P n-9 (W -249). T hey grade into m assive varieties, represented by sam ple RPn-5 (N -4), taken only in this part w hich belongs to the ore-bearing series.

All the above m entioned units are, in general, m ineralized. M ineralization occurs locally in the lop part o f R otliegendes w hich, in this case, is often w hite in colour. T he dom inant ore m inerals arc iron and copper sulphides (pyrite, chalcopyrite, bom ite, digenite, chalcocile, covellite) (M ayer and P ies

trzyński, 1985).

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Fig. 2 The lithologie column of the o r e -b e a r in g s e r ie s . A - sandstone (B s l) , B - sandstone cemented with anhydrite ( B s l ) , C - boundary do

lomite (Calp), D - organic-rich shale, Kupferschiefer (T l), E - marly shale, K upferschiefer ( T l), F - carbonates (Cal)

B

METHODS

M ethods of organic m atter m aceration

T he crushed sam ples (about 10 g) w ere twice acid treated (HC1 follow ed by HF). T hen, the organic m atter from the residue was obtained by w ashing, sieving (25 [Am) and heavy liquid (ZnCl2 solution) separation. T he heavy liquid drifting fraction was collected separately from that being in suspension in o rder to select the heavier organic fraction w ith entrapped sulphides from the sulphide-lean (lighter). They w ere referred to as heavy and light fractions, respectively. The obtained residues w ere applied on cover slips (22 x 22 mm ) and m ounted in D epex. In each slide all recognizable palynom orphs w ere considered as 100%. M oreover, the ratio o f palynom orphs to am orphous m a

terial was estim ated.

Organic geochem ical analysis

T he kerogen fo r pyrolysis was obtained from the organic m atter unsepar

ated from the m ineral m atrix by S o x h let’s extraction with the toluene/m eth

anol (1:3, v/v) fo r4 8 h .

Legend:

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P y ro ly sis-g as ch rom atography Py(610°C )-G C . It w as carried o ut using Varian 3700 gas chrom atograph equipped w ith a Curie point pyrolysis device and a fused silica capillary colum n CP Sil-C B (25m x 0.32m m , film thickness 0.42 |o,m). T he 610°C Curie point ferrom agnetic wires w ere used. H eating tim e w as 10 s. H ydrogen was applied as carrier gas. T he program m ed oven heating ratio was the follow ing: an isotherm al period o f 5 m in at 0°C, then 3°C/m in from 0°C - 320 °C and a final isotherm al period o f 10 m in at 320°C.

P yrolysis products o f kerogen w ere exam ined by a FID detection system . G as chrom atography - m ass spectroscopy Py(610°C )-G C -M S. It w as car

ried o ut using a H ew lett-Packard 5840 gas chrom atograph com bined w ith a V G -70S m ass spectrom eter which operated w ith electron energy at 70 eV and the m ass range m /z = 50 - 800 was scanned every 1.8 sec. T he gas ch ro m ato graph w as equipped w ith the sam e colum ns as described above. H elium w as used as carrier gas. T he oven heating ratio was program m ed as for the Py-G C unit.

RESULTS

Palynology and organic petrography

Palynofacies w ere characterized using the term inology proposed by Van B ergen et al. (1990). O rganic m aterial exam ined is com pletely dom inated by orange and brow n organic debris, the content o f w hich ranges from 85.00 to 99.5 %. T he rem aining part is represented by palynom orphs. T h e ir content increases w hen going upw ards along the profile. The type o f organic m atter is uniform in all the investigated sam ples.

P alynology. In the sam ples exam ined distinct dom inance o f m iospores (97.7% ) over acrytarchs (2.3 %) is observed. The m ost abundant genus is Lueckisporites vrikkiae Potonie et Klass (1954) (Pl. I: 1). L ess frequent are taxons o f the genera: Jugasporites (Pl. I: 3), Klausipollenites (Pl. I: 4), Triad- ispora, Limitisporites (PI. I: 5), Cordaitina (PI. I: 7), Hamiapollenites, Liina- tisporites (Pl. I: 7), Veryhachium (Pl. I: 8) and Leiospheridia. A crytarchs are represented by three genera: Baltisphaeridiiim (Pl. I: 7), Veryhachium (Pl. I:

8) Leiospheridia. Taking into account the applied m ethod o f separation (sieves 25 (im), it m ay be supposed that acrytarchs real content is higher.

O rg a n ic p e tro g ra p h y . O rganic debris occurring in these rocks can be subdivided into two groups:

i. S tructureless organic debris (exinite-type) (Pl. I: 9) w hich in several sam ples practically represents the w hole organic m aterial. Two varieties of this debris w ere found to occur. T he first is characterized by distinctly shaped m argins and occurs in the form of transparent orange flakes (Pl. II: 1). The second is distinctly porous, spongy and its colour changes from orange to dark brow n (Pl. Ill: 1).

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Kupferschiefer Fig. 3 Gaschromatogramofthe kerogenpyrolysisproducts, o — n-alk-l-enes,H - n-alkanes, C7-the numbers refer to the numberofcarbon atoms ofn-alk-l-enes and n-alkanes, T -toluene, E -ethylbenzenes,X -xylene (dimethylbenzenes), N- naphthalene, M -methylnaphthale- nes, D -dimethylnaphtalenes,nor-Pr -nor-pristane, ¥ - impurities

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ii. Structural organic debris. This type o f organic m atter is represented by fragm ents o f land plants (m ost often vitrinite) such as: elongated pieces o f wood (Pl. I: 10; Pl. II: 2), vascular veins or sieving plates.

T h e w hole organic m aterial is poorly preserved. It contains num erous pores and depressions, often filled w ith opaque rounded sulphide aggregates.

T he sulphides are often entrapped w ithin organic grains (Pl. I: 3; Pl. Ill: 2). In the p o lle n grains su lp h id es are m ain ly co n cen trated w ith in th e ir cen tral bodies. O n the other hand, silphides abound in structureless organic debris.

C onsequently, ju s t this type o f organic m atter has been enriched w ith heavier fraction w hen applying this separation m ethod.

Scanning m icroscope im ages reveal the inner arrangem ent o f grains of m etal sulphides, not rem oved during dem ineralization in acids. They are re p resented only by fram boids o f various types. O ne o f these fram boids, co n sist

ing o f larg er grains (as nuclei) and surrounded by sm aller ones grouped in outer (partly destroyed layer) is presented in Pl. Ill: 2. M oreover, organic envelopes, em bedding individual fram boid grains are visible in the picture.

Pyrolysis gas chrom atographic analysis Py(610°C)-GC

T he products o f pyrolysis w ere identified, if necessary, by m eans o f m ass spectroscopy Py(610°C )-G C -M S and the obtained spectra interpreted by com paring them w ith the data presented in M cLafferty and S tre u fe r’s (1989) cata

logue.

A high content o f organic carbon (TOC) in the m aterial analyzed (on the average 6% TO C) allow ed to use for pyrolysis, kcrogen w hich was n ot separ

ated from the m ineral m atrix. Since all the obtained gas chrom atogram s are sim ilar, o n ly one o f them as re p re se n ta tiv e (sam ple R P n-9 (W -249)) is presented in Fig. 3.

The pyrolysis products o f all the sam ples exam ined are dom inated by a hom ologue series o f n-alkanes and n -a lk -l-e n c s, w hereby the m ost intense peaks are due to hydrocarbons characterized by the length o f chains from C6 to C i i (Fig. 3). A m ong isoprenoids, the peak corresponding to nor-pristane is observed. Only toluene is as com m on as aliphatic com pounds, being even the dom inant organic com ponent eg. in sam ples RPn-9 (W -249) and L-15. O ther alkyl derivatives o f benzene are represented by xylene (C2-alkylbenzenes) and C3-alk y lb e n zen e. B icy clic arom atic hy d ro carb o n s are represented by the naphthalene hom ologue series. The m ost intense peaks are due to m ethylnaphthalene isom ers. T he 1-m ethylnaphthalene peak is tw ice as intense as that of 2-m ethylnaphthalene. P olycyclic arom atic hydrocarbons are n ot detectable.

S ulphur organic com pounds are represented by Ihiophene and benzothiophene derivatives.

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CONCLUSIONS

K erogen, defined as organic m atter insoluble in generally applied organic solvents (D urand, 1980), w as until recently considered as a p roduct o f random c o n d en satio n and p o ly m eriza tio n reactio n s o f re lativ e ly sm all m o lecules form ed in sedim ents as the result o f degradation o f biom ass. T hus form ed protokerogen is, subsequently, in the course réactions, transform ed into inso

luble, non-hydrolyzable m acrom olecular polym er - kerogen (B rooks, 1981;

T issot and W eite, 1984).

A ctually, how ever, it was found that Ihe origin o f kerogen is due to selec

tive preservation in sedim entary environm ent o f “biom acrom olecules” - som e prim ary niacrom olecules (Tegelaar et al., 1989). C onsequently, kerogen is no longer treated only as the result o f the accidental processes m odified by p u re

ly geological factors. T herefore, it is often possible to relate its chem ical structure to that o f its biological precursors.

In the case o f am orphous (structureless) organic m atter from the copper- bearing shales, gas capillary chrom atographic analysis o f its kerogen p y ro lysis products has show n that this organic m atter consists alm ost exclusively o f aliphatic structural units. In nalure, insoluble, non-hydrolysable, m acro- m olecular highly aliphatic resistant to (bio)chem ical degradation biopolym ers form protective envelpoes o f higher plants (cutan* and suberan*) as w ell as cell w alls o f sam e algae species (algaenan*) (Nip, 1987; T egelaar et a l., 1989;

G oth et al., 1988). T he obtained chrom atogram s are as those o f kerogen o f the d o cu m e n te d alg al o rig in due to p re se rv e d m o rp h o lo g y w hich w ere e n countered in M essel Oil Shale (Goth et al., 1988). They are also sim ilar to P y-G C chrom atogram s o f culin separated from the bitum inous coal (N ip,

1987).

Till now, only hypotheses concerning the origin of organic m atter in the L o w er S ilesia co p p er-b earin g shales have been p resented. P hytoplancton, algae and bacteria w ere proposed as its source m aterial (fide Saw tow icz,

1991). T he results o f the present studies allow us to exclude the participation o f som e organism groups in form ation o f the kerogen as w ell as to concentrate further research on algae and higher plants. Because o f sm all am ounts o f spores and pollens encountered (from 0.5 to 15%) and subordinate content o f h igher plants rem ains in the analyzed palynofacies, it is concluded that the kerogen in question is not com posed o f cutan and suberan only. It should be em phasized that in both these types o f organic m atter prim ary m orphology is usually preserved that is not observed in organic m atter o f the copper-bearing shales. A fter elim ination of higher plants as the source o f organic m atter, only algaenan has highly aliphatic nature and therefore, can be considered as the source substance for kerogen. A part from geochem ical data, algal origin of

* - the terms refer to the ch em ical com pounds o f w hich the maceral is built o ff. eg. alginil is built o f algaenan (Tegelaar cl al.. 1989)

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this m atter is suggested also by sedim ent structures o f the copper-bearing shales, sim ilar to those reported for sedim ents o f the docum ented algal origin (G oth et al., 1988).

B eside o f that, thiophene structures w ere found in kerogen o f the copper- bearing shale. T hese types o f structural units docum ent indirectly the presence o f anaerobic, sulphate reducing bacteria by recording the products o f their m etabolism (Sinninghe D am ste & de Leeuw, 1992). T hiophene derivatives are the reaction products o f hydrogen sulphide, m ainly produced by bacteria, w ith labile organic com pounds (op. cit., 1992). Consequently, since the labile o r

ganic com pounds o ccu r in relatively fresh sedim ents, the organic sulphur com pounds are the indicates o f H2S-oversaturated oxygen-lean environm ent existing during the sedim entation.

It is w orth em phasizing the observed phenom enon o f incorporation o f m et

al sulphides into the organic matter. M icroscope observations have show n that even m ultiple treatm ent w ith acids does n ot lead to com plete rem oval of sulphides from organic m atter. Some part o f sulphides, displaying only fram - boidal m orphology (PI. Ill: 2) is strongly bound to structureless organic debris w hat was confirm ed by enrichm ent o f heavy fraction in this group o f m in e

rals. P yrite is dom inant in this group as insoluble in acids applied in the m aceration process.

In a sedim ent, the preservation of fram boids is possible in the case of rapid isolation o f new ly form ed sulphide phases from the solvent. T he role o f this isolating phase can be played by organic m atter (Ferrand, 1970), w hich is preserved in the form o f organic envelopes around fram boids in the case o f copper-bearing shales in question (Pl. Ill: 2). M oreover, iron sulphides had to survive the process o f replacem ent o f iron by copper ions due to d ifferen ce in electrochem ical properieties of these chem ical elem ents. The coexistence o f pyrite and copper sulphides in the closest vicinity im plies selectivity o f this process to som e grains. This selectivity is explained by the low er speed of the rep lacem en t reaction fo r pyrite than fo r iron m onosulphides (Saw low icz,

1992).

H ow ever, the occurrence o f organic envelopes sealing iron sulphide grains (Pl. Ill: 2) suggests that they caused the persistence o f iron sulfides, no m atter w hat the affinity o f iron sulphide phases fo r the copper replacem ent and how abundant the copper ions in the later stage o f m ineralization process.

ACK NO W LEDG EM ENTS

T he authors are indebted to geologists o f the K G H M “P olska M iedź S .A .” : A. Zim och, A. Tom alik, W. Szarow ski and J. Srnyj for th eir help in collecting the sam ples for this study and to W. K ilarski and J. F ab er (Institute o f B iol

ogy, Jagiellonian U niversity) for enabling the perform ance o f SEM investiga

tions. In particular M. R ospondek w ants to thank H. Leerefeld and P. van B ergen (Laboratory o f Palynology and Paleobotany, U trecht U niversily) for

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their com prehensive help. M. R ospondek thanks J. de L eeuw and the research group from the O rganic G eochem istry U nit, D elft U niversity o f Technology for en abling the G C -M S analysis and consultation o f the data obtained. We are grateful to A. F isher fo r correction o f the English tex t and to W. Narbski for review ing the m anuscript.

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S t r e s z c z e n i e

POCHODZENIE SUBSTANCJI ORGANICZNEJ W ŁUPKACH MIEDZIONOŚNYCH DOLNEGO ŚLĄSKA

M. J. Rospondek, A. Fijałkowska & A. Lewandowska

S traty fik o w an e zło ża m iedzi, do których należą złoża dolnośląskie, są często w zbogacone w m aterię organiczną. M ikroskopow a analiza m aterii o r

ganicznej w ystępującej w przebadanych litofacjach łupka m iedzionośnego p o kazuje, że m ateriał ten je s t zbudow any głów nie z bezstrukturalnych orga

nicznych debris, a rozpoznaw alne debris organiczne tj. w iązki przew odzące roślin, fragm enty drew na oraz p alinom orly w ystępują w podrzędnych ilo ściach. Celem określenia chem icznej natury dom inującej ilościow o, m ik ro s

k o p o w o n i e i d e n l y f i k o w a l n e j m a t e r i i o r g a n i c z n e j n a p o z i o m i e m olekuła m ym użyto kapilarnej gazow ej analizy chrom atograficznej p ro d u k tó w p y ro liz y k e ro g e n u . B y ły o n e id e n ty fik o w a n e na p o d s ta w ie spektrogram ów m asow ych Py(610°C )-G C -M S. K erogen w ystępujący w łupku m iedzionośnym je st zbudow any z ugrupow ań alifatycznych (stw ierdzono n- alkany i n -a lk -l-e n y ). Tak zbudow ane są odporne na degradację biopolim ery w ysępujątce w glonach (algaenan) i epiderm alnych błonach roślin w yższych (suberan i cutan). Poniew aż nie stw ierdzono m ikroskopow o obecności ep id er

m alnych błon roślin, elim inuje to rośliny w yższe i w skazuje to na glonow e źródło m aterii organicznej. O becność strukturalnych jed n o stek tiofenu w k ero g e n ie je s t w sk aźn ik iem a n a ero b o w y ch w arunków w śro d o w isk u se

d y m en tacy jn y m . B e z stru k tu ra ln a m ateria o rg an iczn a w zb o g aco n a je s t w siarczki w porów naniu z innym i typam i m ateriału organicznego. Siarczki m e

tali są bezpośrednio zw iązane z am orficznym m ateriałem organicznym i w ys

tępują w yłącznie jako 1'ramboidy. M ateria organiczna tw orzy otoczki w okół z ia rn sia rc z k ó w , k tó re d o k u m e n tu ją rolę ja k ą o d e g ra ła o n a w p ro c e sie z ło ż o w y m : a) u m o ż liw iła p o w s ta n ie 1'ram boidów p rz e z o d iz o lo w a n ie w ydzielonych faz siarczkow ych od środow iska sedym entacyjnego, b) odcięła u fo rm o w a n e fram b o id y do m ie d z io n o śn y c h ro ztw o ró w m in e ra liz u ją c y c h um ożliw iając zachow anie się siarczków żelaza.

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EXPLANATION OF PLATES

Plate I

All magnifications are about xlOOO (if not stated otherwise).

1 — Lueckisporites virkkiae Potonié et Klaus, 1954 Norm Aa. Unit II, sample RPn-1 (N-6), light fraction

2 — Lunatisporites noviatdensis (Leschik) Scheming, 1970. Unit IV, sample RPn-5 (N-4), heavy fraction

3 — Jugasporitesparadelasaucei Klaus, 1963. Unit II, sample RPn-1 (N-6), light fraction 4 — Klausipollcniles schaubergeri (Potonié et Klaus) Jansonius, 1962. Unit II, sample RPn-1

(N-6), light fraction

5 — Limilisporites mocrsensis (Grebe) Klaus, 1963. Unit II, sample RPn-1 (N-6), light fraction 6 — Cordaitirui donelzianci Inosova, 1976. Unit IV, sample RPn-5 (N-4), heavy fraction 7 — Ballisphaeridium sp. Unit II, sample RPn - 9 (N-6), light fraction

8 — Veryhachiurn reducluni var. trispinoides Jekhowsky, 1961. Unit III, sample RPn-1 (N-4), light fraction

9 — Concentration o f palynomorphs within structureless organic debris, x200. Unit II, sample RPn-1 (W-249), light fraction

10 — Structural organic debris - wood remains (vitrinite). Unit III, sample L-15, light fraction

Plate II

1 — Structureless organic debris (exinite - type), SEM x600. Unit II, sample RPn - 9 (N-6), light fraction

2 — Structural organic debris - wood remains (vitrinite), SEM x600. Unit II, sample RPn-1 (W-249), light fraction

Plate III

1 — Structureless organic debris (exinite - type), SEM x2000. Unit II, sample RPn - 9 (N-6) 2 — Frainboid within structureless organic matter forming an organic envelope (partly de

stroyed) with distinct organic rims around individual grains (in the right side), SEM x 7200.

Unit II, sample RPn - 9 (N-6)

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M. J. Rospondek et al. P L I

Ann. Soc. Geol. Poloniae vol. 63

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M. J. Respondek et al. Pl. I ll