Decis沙on嚓LochkovianA-W}j 一.rragian rDounciary

Stratotype (Lower Devonian)妙Ivo Chlupk and William A. Oliver, Jr.The Global Stratotype Section and Point (GSSP) for theLochkovian-Pragian Stage (middle Lower Devonian) has nowbeen agreed upon. The boundary is defined at the firstoccurrence of the zone conodont Eognathodus sulcatus

represent aprogressionments.

QuarryChuchle

because

fossils.

Rangessimilar;distance

Cerna rokle has

from low to high energy environ-the best megafauna while Cik5nka

has the most abundant

is intermediate and was

of the good intermixture

conodont

selected

fauna. Velkg

as stratotype

sulcatus at the base of bed 12 in the Velkfi Chuchle Quarry,下丽万而rthwest part of Prague, Czechoslovakia.

of conodonts and mega-

Introduction

The Lower Devonian stages, from oldest to youngest, areLochkovian, Pragian, and Emsian. The base of the Loch-kovian coincides with the base of the Lower Devonian Series

and of the Devonian System and has been formally definedas the Silurian-Devonian boundary (Martinsson, ed., 1977).The boundary between the Lochkovian and the Pragian is thesubject of this paper. That between the Pragian and Emsianis undefined and is the subject of ongoing discussions withinthe International Subcommission on Devonian Stratigraphy(SDS), a unit of the International Commission on Stratig-raphy (ICS) of IUGS. The names of the Lower DevonianStages were adopted by SDS in 1983, recommended to ICS in1984, and ratified by IUGS in 1985 (Bassett, 1985).

Regional Setting

The boundary beds have been studied in detail at severallocalities in the Barrandian area, southwest of Prague(Fig. 1). Three localities were described in detail by bothWeddigQ.0987) and ChlupA6, Lukeg and Weddige (1988). Thethree, CernA rokle, VelkA Chuchle and Cikfinka Quarry,

ofaL

bounda四．

key specieseach localitybelow the

ChlupA6 and

at the three localities

the翌竺丝些 boundarypreviously acceptedothers (1985) published

range charts and lists of fossils from these

are very

is a short

megafossil extensive

and other

boundary sections, together with discussions of thestratigraphic significance and usefulness of the major groupsof fossils of the Lochkovian-Pragian interval.

The boundary is closely related to an event-stratigraphylevel of probable global importance, namely the "Loch-kovian-Pragian Boundary Event," which, however, lies closeabove the Pragian base. This event-boundary (most likely aeustatic

broader

fall in sea level) may be usefulinboundary interval on，a

Ia

worldwide

identifying thescale (compare

the interval before Cycle Johnson, Mapper and

Sandberg 1985, and applicationsChlupA6 and Kukal 1986, 1988).

the stratotype area,．In ．In

Paleomagnetic studiesin

are

in progress by Dr. M. Krs in Prague. Preliminary results

－‘甲－厂一厂N～es尸‘es一一－厂－ 七产只代 乙少户

芙 一了－又

PRAHA

Velk6 Chuchle

I伙aR BEROUN

降、马创冲

洲

｝1

。一}1_1 IROKYCANY

I称舒｝！

邓10 20 km

‘ 一一一」

1田11 2F刀 3区次｝注一墓 I I二口6压团 7国 。口Figure 1: Geographic and geologic setting of thestratotype section in the Barrandian area of centralBohemia. 1一Proterozoic, 2- Cambrian, 3- Ordovician,

4- Silurian and Devonian, 5- metamorphic Proterozoicand lower Paleozoic, 6- granitoids, 7- continentalUpper Carboniferous, 8-〔孕per Cretaceous andTertiary sedimentary rocks.

suggest that tne vetKa 七huchle section has been

remagnetized. The color alteration index of VelkA Cbuchle

conodonts is 3 (Sch6nlaub, written communication, 1989).

Prior to the naming of the Pragian Stage in 1958 and itsacceptance by SDS in 1983, the "Siegenian Stage" was usedby many workers for the middle stage of the LowerDevonian. This was based on benthic, near-shore fossils,principally brachiopods, and was sufficiently useful up toabout 1950 when pelagic fossils such as conodonts began topredominate in long-range correlations. With continuingrefinement of intercontinental correlations, it became clearthat the I'Siegenian Stage" could not be satisfactorilydefined in its type area (West Germany) and the shift toPragian resulted.

Recent studies in northern Spain, Brittany and WestGermany show that the base of the Pragian is nearly correl-ative with the base of the "Siegenian" in the sense of Carls(1987). One option would have been to select a GSSP for the"Siegenian" in a pelagic facies (e.g., Czechoslovakia), butthe SDS decision to use the term "Pragian" reflects thefeeling that the term "Siegenian" is too closely regarded interms of a Rhenish, near-shore clastic, benthic facies,whereas "Pragian" signifies a diverse fossil assemblage thatincludes widespread pelagic fossils.

Boundary Stratotype (GSSP)

The position of the Lochkovian-Pragian boundary and theGSSP for it were accepted by the International Subcommis-sion on Devonian Stratigraphy in August-October 1988, andapproved by the International Commission on Stratigraphyand ratified by the Executive Committee of IUGS duringJanuarv-February 1989. The stratotype is to be marked by

EPISODES, Vol. 12, No. 2, June 1989 109

a plaque with explanation, and a permanent metal line is tobe inserted in the rock face at the boundary. Marking andmaintenance will be done by the Geological Survey ofCzechoslovakia, in collaboration with the Center forNatural Reserves, also in Prague.

The GSSP

Prague, inold quarry

of the sulcatus boundary is in southwesternthe secti而不re_IkA Chuchle (Fig. 1). This is an

。。 ihp rnqri from Praha-VeIkA Chuchle toSlivenec onV dolich Street V fdoli), 8 km southwest of thecity center. The quarry is on the nature reserve called"Homolka," in the district of Prague 5; the distance from acity bus terminus is about 400 m (Figs. 2 and 3). In theVeIk9 Chuchle section, the stage boundary is defined as thebase of Bed 12, at the first occurrence of E. suicatussulcatus.

一‘} MCI6／“

，‘，Ch些}I ／下

匕二，’ ＼

、爪个小个

Slivenec

。 ＿＿． ），

少夕12几一，气“， strofotype }

小‘｛

planes are knobby; the characteristic nodular structure isdeveloped in micrites and biomicrites with Chondritesburrows that start 2 to 3 m above the stage boundary.

Boundary Level (base of Pragian)

The stage boundary was chosen by SDS in 1988 to coincidewith the lower boundary of the Eognathodus sulcatus cono-dont Zone defined by the first occurrence of互.一 sulca生ussulca生矍 Philip, 1965. In some discussions this has beenreferred to as the sulcatus boundary. The E. sulcatus Zonewas first defined by Fahraeus, 1971, and has since beenaccepted as part of the standard conodont zonal sequence(KIapper and Johnson, 1982). The name taxon and zone arenow recognized in Czechoslovakia, Germany, Austria,China, Australia, U.S.A. (Nevada, Alaska) and Canada (seeWeddige, 1987, p. 484-5, for details). Although nearlyworld-wide in distribution, it has not yet been recorded orrecognized in the Soviet Union or eastern North America.These are major geographic gaps, but it seems likely thatthe former, at least, will be filled. Maximum provincialismand inappropriate lithofacies in eastern North Americamake it less likely that the zone will be recognized in thisarea, but other criteria permit approximate correlations.

///IP'OOV E. sulcatus sulcatus is thought to be part of a lineage that

‘与今 今HomolkaI ，

proceeds from Ozarkodina pandora (early and late forms) toE. sulcatus (early and late forms). A series of morphotypes孙

勺

孜软Vy D}7701-1._4,VVelkIVelka Chuchle

rOO

＿万，乙‘ ＿ 呻尹

少全

＂行Lochkov 仇 't 9z}'

，匹二刁2巨二困：尹 ‘了 5厂 0 1km ． I

Figure 2: Map of immediate vicinity of Velk5Chuchle and the stratotype section. 1一urbanizedareas, 2- forests, 3- highways, 4- railway, 5-broo.ks.

described in each species has biostratigraphic usefulness(Murphy, Matti and Walliser, 1981). The general sequence inthe Pragian type region is illustrated by Weddige (1987, figs.2-6). The defining morphologic character of the earliestsulcatus is remarkably clear (Weddige, 1987, p. 481).

Graptolite zonation. The boundary level lies above thegraptolite Zone with Monograptus hercynicus, which istraditionally included in the upper Lochkovian. Nearlyworldwide in distribution, it is known from Czechoslovakia,Thuringia, the Carnic Alps, Yugoslavia, Bulgaria, Sardina,NW Africa, the northern Ural mountains, Fergana, CentralAsia, Malaya, Thailand, South China, Alaska, and westernNorth America (Jaeger, 1979; Koren, 1979).

The outcrops have been studied since Barrande's time (early19th century), and the structure was clarified in the secondhalf of the 19th century. Biostratigraphic studies of theLochkovian and Pragian were carried out by ChlupA6 in the1950s, and detailed investigation of the boundary interval byChlupA6, Luke}, Paris and Sch6nlaub (1985) and Weddige(1987). The outcrop was visited by the Devonian Subcom-mission in 1986 (described in Chlupg6, Hladil, and Lukeg,1986).

The outcrop exposes a synclinal structure formed by Loch-kovian strata (limbs) and Pragian strata (core). TheLochkovian-Pragian boundary beds are exposed in bothwestern and eastern limbs of the syncline. The section onthe western side, where the beds form several simple folds,is the stratotype (Figs. 4, 5). In the eastern limb of thesyncline the beds are vertical.

The upper Lochkovian consists of gray, fine-grained, blo-detrital, bituminous platy limestones with uncommon chertsand subordinate very thin intercalations of calcareous mud-stone beds that are millimetres to a few centimetres thick.

The Lochkovian-Pragian boundary, based on the first occur-rence of Eognathodus sulcatus, lies within this sequence,which shows no marked lithologic change.

Except for its lowest part, the Pragian sequence is repre-sented by the Dvorce-Prokop Limestone. This is light gray,biomicritic to finely biodetrital in the lowest part andpasses upward into darker gray micritic limestones. Bedding

Dacryoconarid (tentaculite) zonation. The boundary isabove the Paranowakia intermedia Zone, which is tradi-tionally included in the upper Lochkovian and is also wide-spread (Europe, northwest Africa, Asia, and Australia). Thebase of the subsequent Zone with Nowakia sororcula (possi-bly二N. kabylica， see Alberti, 1988T -lie,,币而而面ow the

劫 ．

5［ivenec．

叮赛巍

皱侧引权

．

户

、

以0 500 m

Figure 3: Detailed map of stratotype location.

110 EPISODES, Vol. 12, No. 2, June 1989

终

汀竿淡

瀑 黔骥

Fossils

The occurrences of conodonts, chitinozoans and other index

攀徽 鑫 一奢邵 爹妾 fossils are summarized in Figure 6 and detailed in Figure 7.

The uppermost Lochkovian contains mostly fragmentalmacrofossils identical with those from

localities: trilobites (LeDido,other nearby

roetus Ie

RanuncUlODroetus heteroclytus, Leonasidus lepidus,

lochkovensis,SDiniscutellum Iasi, small

chonetid, strophomenid index Areostro

and

}hia interjecta,andothers), atrypid and rhynchnonel-lidbrachiopods; thin-shelled

了 r1l_ bivalves (Neklania, Hercynella, Panenka), gastropods,nautiloids, phyllocarids, etc. The characteristic upperLochkovian macrofossils continue up into bed No. 12. that is

above the first occurrence of Eognathodus sulcatus.

A A:

redef i ned

traditionalboundary

boundary

ower Pragian

9，OPt

几一！。

late upper Lochkovion

Figuremarks

4 : View of

the boundarythe wall of the old quarry. A--Ainterval shown in Figure 5.

Monogroptus hercynicus

Mon.kayseri

冲en冲OOC一二巾5

boundary, while the lowest occurrence of typical specimensof the worldwide Pragian index Nowakia acuaria s.s. isabove the boundarv: N. cf. acuaria occurs below the

oounaary tsee L;niupac, LUKeS, Faris ana z!icnonlaul), IV60).

N. acuaria is known from Europe (Bohemia, Thuringia,Franconia, Moravia, Harz Mts., Rhineland, Spain, Sardinia,Carnic Alps, Amorican Massif), Asia (Urals, Central Asia,Siberia, Burma, Tibet, China), northwest Africa (Morocco,

Poranowok‘口intermedia州一— － Nowakic sororcuto

NOW

I一一

！

lacuorio一一》

CO口OdO，ts

Algeria), North AmericaAustralia (see summaries

(Alaska, Canadian Arctic) andof occurrences in Alberti, 1979,

Ozarkodina remscheidensis

1987, LUtke 1979, 1985).

Chitinozoan zonation. This is the

for the correlation of terrigenousmost promising methodelastic and non-marine

Latericriodus sp.n.A

Lotericr. steinochensis

sequences. The boundary falls just below the lowestoccur-

rence of the Pragian index Angochitina comosa close to the

and close to

Pedavis pesavis

first occurrence of Gotlandochitina oti,hili 02 pandoro

the last occurrence of Eisenackitina bohemica (Paris, 1981and in ChluDA6 et al.. 19-8-5犷一一一一一一一一— steinhornensis

Oh一t︸刀0200二5

It is inevitable that some of the ranges shown for taxa in theVelkA Chuchle section will prove to be incomplete whenstudied on a worldwide basis, but the correlation potentialof the boundary level is worldwide and can be approximatedby means of several different groups of fossils with inter-continental distribution.

Angochitino co印 0SQ

门︸

～

n

一A

Margachitino cotenor旧 cote no ri a

M. catenariai tenuipes一－－一）Gottandochitino romosus

Lochkovetto misero

1 Gott. philippoti｝

一朴一

Reedops timesprogensis

碑r一一Ob－冲es

Spiniscut. umbettiferum

SpiniScuteltum ptosi

Reed. gr. sternbergi

Odontochile

Leonospis lochkovensis

Progoproetus.Gerastos

Lepidoproetus tepidus tepid

不latyscutettumDecoroscutettum

tPoroscutetium

＋M etascuteltum

Figure 5: Boundary interval at stratotypesection. The top of the white bar marks theboundary at the base of bed 12. The bar is

approximately 0.7 m long.

Figure 6: Ranges of selected index fossils ascurrently known in the Lochkovian-Pra好an boundaryinterval in the Barrandian area. 叨〕e interval shown

is approximately

Ranges are from

5 m above and below the boundary.sources cited in the text.

EPISODES, Vol. 12, No. 2, June 1989 111

sequencecontinues

一greycotour

乌葺tentocutites conodonts

I 飞

chitinoz. mocrofos

I I

岔

Prokop Limestone and the speciesbecomes abundant about 2 m higher.

The GSSP, the塑丝蛀些 boundary atthe base of bed 12 (Figs. 5, 7), is0.1 m below the traditional bound-

ary, based on megafossils, at thebase of the Dvorce-Prokop Lime-stone. Bed 12 has "Lochkovian"

lithology and megafauna, indicatingthat the advent of E. sulcatus was

not related to local facies change.

Summary

The E. sulcatus Zone is worldwide in

extent and the name conodont has

greater potential for recognitionand correlation than any knownfossil that occurs anywhere near thetraditional Lochkovian-Pragian

boundary. The position of the sul-cat些．boundary is 0.1 m below thetraditional (megafossil) boundary inthe type section (see Fig. 7).

The proposed stratotype is in aneritic facies of intermediate

energy level and contains a highlydiverse fauna of traditional and

finew" index fossils. Because of this

diversity, the Pragian Stage hasbecome the preferred standard inmany world regions. Selection ofthe GSSP permits greater precisionin recognition of Pragian strata inother parts of the world. The GSSPis on the edge of Prague, Czechoslo-vakia, in a nature reserve whereaccess is easy and preservation isassured.

Acknowledgements

The authors are indebted to other

members of the Devonian Sub-

commission and to many colleaguesfor discussions and help during thetime that SDS has been working onthe Lochkovian-Pragian boundary.Thanks are due J.T. Dutro, Jr., A.G.Harris, and M.A. Murp勺 for review-ing an earlier draft of this paper.

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FigureVelkA

7: Columnar section of boundary interval atChuchle Quarry stratotype section;

and ranges of key fossilsLuke}, Paris and Sch(5nlaubwith addition of ne-w dit-,i

are shown.

n厂lithology

After Chlup}6, (1985)

(1988)。and Weddige (1987)

1一 fine

biodetrital to biomicritic limestones, 2- laminatedmicrites, 3- nodular micrites, 4一shale

intercalations.

Dacryoconarid tentaculites are represented by all importantzonal taxa of the upper Lochkovian一ower Pragian, and thesame is true of conodonts (Figs. 6, 7). Chitinozoans are lesscommon 0 to 4 specimens per gram of rock) but are alsorepresented by index taxa.

Typical Pragian macrofossils, e.gprospicens, Reedops gr. sternbergi,

trilobites (ReedopsOdontochile hausmanni

and allied species,Crotalocephalus lob fr ns，

lum formosum formosum) and the brachiopodPlatyscutel-Dalejodiscus

subcomitans are found in the lowest 5 rn of the Dvorce-Prokop Limestone sequence. The lowest occurrence of the

Dr. 1vo CblupA6 is a seniorgeologist with the CzechoslovakianGeological Survey, (Malostransk6nhm}stf 19, 118-21 Praha 1). Heworks on Paleozoic (mainlyDevonian) stratigraphy, and thepaleontology of arthropods andgoniatites. He is Chairman of theCzechoslovak Stratigraphic Com-mission, Vice-Chairman of theInternational Subcommission on

Devonian Stratigraphy, and a mem-ber of the International Subcom-

mission on Stratigraphic Classifi-cation and several other inter-

national stratigraphic bodies.

index

m ens)Pragian tentaculite Nowakia acuariais about 50 cm above the lower limit

(typical speci-of the Dvorce-

112 EPISODES, Vol. 12, No. 2, June 1989

Dr. W.A. Oliver, Jr. is a researchpaleontologist with the U.S. Geo-logical Survey (E-305 NaturalHistory Bldg., Smithsonian Institu-tion, Washington, D.C. 20560). Hisresearch interests are Late Silurian

and Devonian rugose corals andbiostratigraphy. He is a past presi-dent of the Paleontological Soci-ety, the Paleontological ResearchInstitution and the American Geo-

logical Institute, and currentChairman of the Subcommission on

Devonian Stratigraphy.

黔 子 ChlupA6,1 1. and Kukal, Z., 1988. Possible global1 events and the stratigraphy of thePalaeozoic of the Barrandian (Cambrian-Middle Devonian, Czechoslovakia).Sbornik geojogickych Ved, v. 43, p. 83-146.

ChlupA6, I., Illadil, J. and Lukes, P., 1986. Field Conference, Barrandian-MoravianKarst 1986. Excursion Guidebook, Field Conference of the InternationalSubcommission on Devonian Stratigraphy, 62p., Praha.

愁pA6, L, Lukes, P.,1 Paris} F. and Schbnlaub, H.P., 1985. The Lochkovian-ian boundary in the Lower Devonian of the Barrandian area (Czechoslovakia).Jahrbuch der Geologischen Bundesanstalt, v. 128, p. 9-41, Wien.

Chlu[)96. L. Lukes. P. and WeddilZe, K., 1988. Candidates for a new Lochkovian-

PraLian boundarv stratotVpe in the Barrandian area, Czechoslovakia. Material

submitted to the Subcommission on Devonian Stratigraphy, Rennes 1988, 1 Ip.

Fahraeus, L.E., 1971. Lower Devonian conodonts from the Michelle and ProngsCreek formations, Yukon Territory. Journal of Paleontology, v. 45, no. 4,

p. 665-683.

Jaeger, H., 1979. Devonian Graptolithinia.竺：The Devonian System. SpecialPapers in Palaeontology, v. 23, p. 335-339, London.

References

Johnson, J.G., Klapper,fluctuations in Euramerica.

p. 567-587.

G. and Sandberg, C.A., 1985. DevonianGeological Society of America Bulletin, v.

eustatic

96, no. 5,

Alberti, G.K.B., 1979.herzynischen Unter- undp. 223-241.

Zur Dacryoconariden一Tentaculiten) Chronologie desMittel-Devons. Senckenbergiana lethaea, v. 60, no. 1-3,

Alberti, G.K.B.,mitteldevonischer

Senckenberg,no.

Alberti, G.K.B.,

1987. Zur palNobiogeographischen Verbreltung unte卜 und Dacryoconarida (Tentaculiten). Courier Forschungs-institut

92, p. 161-176.

1988. Stratigraphische

/Pragium-Grenzprofile (Unter-Devon) in Untergliederung einiger LochkoviurnNW-Marokko, Oberfranken und Victoria

(SE-Australien) auf Grund von Daeryoconariden and Conodonten. Sencken-

berglana lethaea, v. 68, no. 5-6, p. 479-493.

Bassett, M.G., 1985. Towards a "common language" in stratigraphy. Episodes, V. 8,

no. 2, p. 87-92.

Carts, P., 1987. Ein Vorschlag zur biostratigraphischen Redefinition der GrenzeGedinnium/Siegeniurn und benachbarter Unter-Stufen. Erster Teil: Stratigraph-ische Argumente und Korrelationen. Courier Forschungsinstitut Senckenberg,no. 92, p. 77-121.

ChlupH, 1. and Kukal, Z., 1986. Reflection of possible global Devonian events inthe Barrandian area, CSSR. Lecture Notes in Earth Sciences, v. 8, p. 169-179,G6ttingen.

Koren, T.N., 1979. Late monograptid faunas and the problem of graptolite extinc-

tion. Acta Palaeontologica Polonica, v. 24, no. 1, p. 79-106.

Klapper, G. and Johnson, J.G., 1980. Endemism and dispersal of Devonian cono-donts. Journal of Paleontology, v. 54, no. 2, p. 400-455.

LUtke, F., 1979. Biostratigraphical significance of the Devonian Daeryoconarida.In: The Devonian System. Special Papers in Palaeontology, v. 23, p. 281-289,London.

Ldtke, F., 1985. Devonian tentaculites from Nevada (U.S.A.). Courier Forschungs-

institut Senckenbe馆，no. 75, p. 197-226.

Martinsson, A. (ed.), 1977. The Silurian-Devonian Boundary. IUGS Series A, no. 5,

349p., Stuttgart.

Murphy, M.A., Matti, J.C. and Walliser, O.H., 1981. Biostratigrap勺 and evolution

of the旦zarkodina remscheiden丝竺Eognatho竺sulcatus lin即多a }Lower甘兮艺哩色n)in Germany and central Nevada. Journal of Paleontology, v. 55, no. 4, p. 747-772.

Paris, F., 1981. Les Chitinozoaires dans le Pal6ozo-que du sud-ouest de 1'Europe(Cadre g6ologique, Etude syst}matique, Biostratigraphie). M6moires de in Socik6g6ologique et mi能ralogique de Bretagne, no. 26, 412p.

Weddige, K., 1987. The lower Pragian boundary (Lower Devonian) based on theconodont species E呀nathodus sulcatus. Senckenberggiana lethaea, v. 67,p. 479-487.

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EPLSODES, Vol. 12, No. 2, June 1989 113

ANALYTICAL METHODS

FOR GEOCHEMICAL

*}'40 1161; TA d 191Z

J.C. Van Loon and R.R. Barefoot

Written for the practicinganalyst, Analytical Methods forGeochemical Exploration offersthoroughly tested chemical analy-sis methods for determining whatbase or precious metals are in geo-chemical exploration samples,such as rocks, soil, or sediment.

Theory is kept to a minimum andcomplete procedures are providedso that no additional sources are

needed to conduct analyses.

1988, 344 pages, $49.95ISBN: 0-12-714170-7

THE TECHNIQUES OFMODERN STRUCTURAL

GEOLOGY

Volumes I and 2

John G. Ramsay andMartin I. Huber

七我签挺盛翔寿幻盘挑慧沈艺甜 爱昆迸瑟蕊续夔 盗登盔慈建地维

BASIN ANALYSIS

Quantitative Methods

Ian Lerche

This is the first book in its field

to deal with the quantitative as-pects, uncertainties, and resolu-tion limits of basin analysis. Thepurpose of this volume is to inte-grate knowledge of the dynamical,thermal and hydrocarbon historiesof sediments and fluids throughgeologic times using quantitativemethods. The emphasis is on theuncertainties and resolution limits

of basin analysis given constraintsderived from surface and downhole

data and the sensitivity to modelinput parameters and assump-tions.

November 1989, c. 476 pages$89.50 (tentative)ISBN: 0-12-444172-6

APPLIED

SEDIMENTOLOG丫

Richard C. Selley CONTENTS: Rock to Sediment:

Weathering and the SedimentaryCycle. Particles, Pores and Perme-ability. Sediment Sedimented:Transportation and Sedimentation.Sedimentary Structures. Environ-ments and Facies. Sediment toRock: The Subsurface Environ-ment. Allochthonous Sediments.Autochthonous Sediments. Sedi-

mentary Basins. Each chapter in-cludes references. index.

In Paperback: $34.00ISBN: 0-12-636366-8

Casebound: $79.50ISBN: 0-12-636365-X

1988, 446 pages

Volume 1

In Paperback: $29.95ISBN: 0-12-576921-0

Casebound: $69.00ISBN:O- 12-576901-6

1984, 324 pages

Volume 2

In Paperback: $35.00ISBN: 0-12-576922-9

Casebound: $84.00ISBN: 0-12-576902-4

1987, 407 pages

越潇势公岂蜡吐越遨生出猫婆塞继理竖器老骂得鳄粼攀忿签过舀盔

Now available in paperback!FRACTURE MECHANICS

OFROCK

edited byBarry Kean Atkinson

Paperback Reprint: $39.95ISBN: 0-12-066266-3

1989, 534 pagesCasebound: $129.00ISBN: 0- 12-066265-5

1987, 534 pages

ISOTOPE

CHRONOSTRATIGRAPHY

Theory and Methods

Douglas F. Williams, Ian Lerche,and W.E. Full

This is the first title to bring to-gether the latest data and quantita-tive methods of isotope chronostra-tigraphy and signal processing, arapidly developing area of research.Designed to familiarize petroleumgeologists and stratigraphers withthis new form of chemical stratig-raphy, the authors attempt to showthe potential of using stable oxygenand carbon isotope records formaking detailed stratigraphic cor-relations of exploration sections ofTertiary and Mesozoic ages.

1988, 345 pages, $49.95ISBN: 0-12-754560-3

a ACADEMIC PRESS

— Harcourt Brace lovanovich, PublishersBook Marketing Department #21069, 1250 Sixth Avenue, San Diego, CA 92 101

C 1989 by Academic Press, Inc. All Rights ReservedCALL TOLL FREE i-soo-32i-5obs

Prices subject to change without notice. DK/ES #21069

114 EPISODES, Vol. 12, No. 2, June 1989