Amanz Gressly's Role in Founding Modero Stratigraphy

8/8/2019 Amanz Gressly's Role in Founding Modero Stratigraphy

1/14

•

Gressly's role

in

founding modero stratigraphy

Depanmelll f G o l o g y wrd ~ o l o g i c a / Engi

nf: erin

g Culomdo

Sclrool

ofMines Gulden.

Colorado

HO JO

1

\V.

Homewood

Elf E.\pl

om

rim r Pmdu

crimr

.

640 8

Pau

cede

x.

France

papel"

dbc:ussn

Amanz Gre.'l.•ly's

fundamental

conlributions to

in lhl'ft arHs: f:ades c o n ~ p u

slndtnphlc corr.l:ation.

~ p h l c

l'ft0fl5trvction. To

f:acil

·

ac«ss

lo

hls dlsco••

eries.

we pre

senl an

tnanslallon

or

hls 1&38

paper

on

f:ac

ies

tnlil npbk

correlation.

We

dl..:uss

tx

•

rrom

lhis

lnulalioft. whidr drmon·

e lhat a a ~ uf he fundamental

princi

·

f modem stntit tnphy

Wft'e

Undrrstood

by (;ressly. We pulthls into thr

of

subsequrnl dr•dopmrnt ond re·

ofCUI'ftlll s

tn tJ tnphk

principies.

t'Xplaiaed lhr creais

or i m e n ·

fodes by procuscs opentinc

In deposi·

ell\ii'IIMMIIts. He detnonstnltd

r t p ·

facies

lr1lnslllooa ~ ,..(

,kh

as

- l a f emlro,,not nts

deposi&..a

r o a ~ a

u e

r m ~ t n i u d :he

of

particular feJ

morphol

ogi

es

parttc:alar

e c l l m ~ ) c a l facles . and

fKies

roulls

rrom lhMe lhal

lime

•lllue

and lhal -

uSdul

f

or

blo

c"lllekx"

or

z - fossilsl.

He

the

eqai'l'altttcy of

vertical

f : ~ c i o s

'

lOo

tluou¡do a

Jeriesofstnta

and

13

1·

flldes la . .,..,.., a

bed.

deftlopin l

Jllilid¡Ae that

aler

becanw

kno,.n as

' s IAw

of

tbe ~ t l O i l of f ucios.

bet'ftftl

the llmc n lur of

...t

PI

utA* rlt5

that

nftrct thérgenesis.

s¡MCillc

tums

lo

reflt


2/14

concep1 airead

y had been

ed

and

abandoned by

o r m : of his

con

(for ex311'1ple. see comrm:nW'ies in

1984). Gressly offered the

ive concepts and methods that were to be

e the foundation

of

modem stratigraphy.

(

1962)

argued that new paradigms in sci

follow a period

of

discomfon with the ~ i s t ·

paradigm because

of

mism:uches between

such a period of discomfort.

Gressly's insightful

departure

from the exist

paradigm contained tltree fundamental. re

concep S.

Fant.

he

recognized thal

the sedi

of

rocks.

of

deposition

specific geomorphic environrm:nts. Sec

he understood that facies occur indepen

of time. and

thal

time and rocks must

be

with

separate conceptS and vocabularies.

he

established that there are predictable

of

facies relationships. He documented

faciesoccur inregular

paw:ms of

ater:tl

ttan·

along a bed. and that

these

laterollr.lnsi·

in venical successions. This

w:IS accomplishedc:uring his early twenúes

from observaúons

rnade

on disconlinuous.

vege

tated outcrops. and without lhe benefit

of

much

formal

geological

training_

lmponant reviews of Gressly s education.

collaboration with his contempor.uies. work

in

the Jura. contributions to stratigraphic science.

and other biographical inforrnalion were given

by Teichen Cl958l. Wegrnann C1963). Meyer

(

1%61.

Schneer (

19721.

Nelson

0985

.

Swnpfli

t 19861.

and Schaer (1994). Gressly was bom in

the village

of

Bllrschwil (Canten de Sololhum)

in the German-speaiUng area ef Switz.erland

near the outer. norlhwestem thrusts of he Jura

Mountains. After pre-university schooling in

Solothum. Luz.em. and Fribourg, he spent sev

era months in Porrentruy (Canten Bem).

Switzerland. to imp 'O"e his French. In Novem

ber

1834.

at the

age oC20,

he went

te

Univmiry

of

Strasbourg to study medicine. While there

he

anended lectures on geology given by Phillippe

Voltz. the chief engineer of the Strasbourg min

er:tl

disuict.

He

became

friends

wilh Julius

Thur

mann. a professor of mathematics and natural

;cience at Porrentruy.

wt.o

also was studying

ge

ology

under

Voltz

in

Slnsbourg.Thunnann s

re·

search was on tbe stnli)ll"'l9hy lUid structure of

the Bemese Jura. He Clll:llllnpdGressly to ini

IÍate parallel and tootple.llCit lll f studies in tbe

adiacent Solorum to tbe east.

In

Jul y

1836.

aftertwo yean

offield

worlc in

the Sulothum

Jura. Gn osly

went wilhThurmann

to Sulothum to present

an

oral paper al the an·

n u ~ l meeune of the

S w 1 s ~

Natur.JI Hisu)rv Soci-

l"lh' •CJ•·nded :lh\tr.ICt nt h1' ¡):lf'("r \\ : t \ puP

CROSS ANO

HOMEWOOO

lished lhe following year CGressly,

1837). In

this

paper Gressly gave a

shon

definition nf sed

i

mentary facies and related the facies he had ot>-

served to depositional environments. The first

pan of Gressly's major work. "Observations

géologiques sur le Jura soleutois." was published

in 1838. apparently with considerable help in

composition and editing from his friends. panic

ularly Thurmann.

At

lhe Sololhum meeting, Gressly also met

LouisAgassiz.lheintemationallyrespected pale·

ontelogist and geologist. Agassiz recognized the

novelty and imponance ofGressly's insights and

command

of

lilhostratigraphic and biostrati·

graphic data. and he encouraged Gressly to

continue wilh his work. Afler publication

of

lhe

first

pan of

the "Observations." Agassiz pro

meted Gressly's work by circulating the paper

widely. In evidence. during the session of the

French Geological Society on November 20.

1837.

M:llt¡Uis

de Roys

t a good friend of Privosl)

reponed on

his

work

on temuns

of

lhe

sou hwest

Paris basin. ending wilh a comment that the

facies of lhese terrains were detemúned by their

aspect.

bu1

not by their age (de Roys.

1837).

After the Solelhum meeting Gressly did not

retum to Strasbourg.

but

went to

Pom:nauy

and

stayed wilh Thurmann.

From

November 1836 to

Janua¡y

1838.

Gressly was in Neuchatel

for

lec·

tures

given by

Agassiz. Subsequently.

he

was

em-

ployed by Agassiz for severa yea.r.; :IS

an

:ISsis·

tant at the Museum of Neuchatelto collect and

curate fossils. Gressly's fossil collec1ion. care

fully collected within a

few

yean and recorded

within

a

stratigraphic context. numbered more

han 25.000 specimens. Between Janua¡y 1838

and

Sep1ember 1839. Gressly was mentally ill.

and

lhere

is an a b s e n c ~ of

correspondence

from

lhat period. This illness delayed publication of

the rest ofGressly's "Observalions" untill840

and 1841. That Gressly did not subsequently

pubtish en facies is attributed to his fragile heallh.

The main

pan of

his work. consisting

of 75

sci·

entificmanuscripts.

51

field

notl book.s. and

myr·

iad personal notes. is stored at lhe Museum

of

Sololhum CSwnpfli. 1986).

Wegmann ( 1963\ casts Gressly as a revolu·

tiona¡y in

lhe

context

of

··normal" versus

r e v ~

lu1ionary" science. using tenns formalized by

T.

S. Kuhn ( 1962). The prevailing geological

notions of the time were

derived

from Wemer's

Neptunist

c o n c e p ~ s .

in which formations were

considered contemporaneous. globally distrib

utl d.

specific rock

rypes.

By contnsl from em·

pirical observation Gressly recognized that a spe·

cific rock type ("facies") reflects its origin in

terrns

ofenvironment and conditions

of

accumu

lation

. not in terrns

of

its age. Rocks of the s

ame

;Jge

t h a n ~ e

< . : h a r . t C I ~ f c·f:tCie \· · , ClV('T Ül -li:ln


3/14

were mnsidmd 11obal in dislribution and

lime · ·m.ver

their

c,_,. ition

or

,

-···...-·

oripn. fviiiWIÍOIIS-

clauifled and

bys-aJ itholocic chlncteri.stics

assemblases which were thought to

each UJtit throulhoot

exr.ensive

ft lions.

fomwlioas occurmt in stratignphic

likc temins. fonnaáons

were

consid·

bod1 time bounded a.nd lithologicatly dis·

. Recognition of a panicular lithology

was

to define

thc

age of the Str.lta being

of time-lithology

the Wemerian

r . ~ d i t i o n .

auumed lithologic identity and global

of

paleoenvironmental conditions

one time

period 10

the nexL

initially

i n ~ n d e d

to use the str.ati·

c o l l e ~ g u e

and mentor

had

clefined

in the Bernese Jura. a.nd

them 10 the Soleute Juratsee q t ~ W ~ n .

. Thlll1 WIII hld established s t r a t i g r . ~ p l l

ions

andCOITebtions

in

the

tnditional

m:ut·

measuring

a series

of stntisfllphic sections

and then correlating the

mata

them.

The

condalions

wae

b:lsed

upon

equivalency.

y;........,-., """'Y O d i e ~ wl>m

lliw

ceoiolitallaws

diOI

Mr.

Thurmonn

wnfied wioh

I'OICh t:llenl and SII(I)CU on

die , . , . . . , ~ ; . ,

un1ts

die nei@hborin111ltlllfi'OI'hlc:

URIU. aftd C:JUSO

:IStO

hmeftl

fot

tho

~ I > C "'iloaltur J ~ \ S I C

r : I I I ~ . I - 7 )

G r e s ~ l y explicitly cautioned again

st

as

si gmng

an a ~ o c to str.lt.:l on the bas is of lithologic h 3 t : l c

terisucs. He w

a ~ M d

that bec:luse litho

log

cc • h:u-·

actenstics

are

u f f i c

ali

ke

in

t r a l l ~ r : l p

units of different ages. a geologist can m

is

take

thc age of a unit if it.s age is judged by lithology.

Similarly.

he

cautioned thal because the sa

me

verbc:ll SUCCCSSIOnSof lithologies

are

rtpealed in

multiple

l f l l t

g r . ~ p h i c units. a gcologist can co

n

sider

s e v e r . ~ l

temporally distinct

g r . ~ p h i c

units as one .

C o m m o n l y . h e t h ~ w i l l s a o p w i l h s u r ¡ m o

in from

of

ronnau

ons he thouahl he knew "-cll

r

or

•

lonJt

time.

l.ed

as""v b'l

100 much

fai.th in

IICCe¡>led

g e o i o ~ i c o l

do@ma. ;.hich orten @tnernlitn puroly

local focts.

he will

pomops

be misWpat ial

vari:uions in lithology within time-equivalent

units. and lhc basis for inferring the pnleo

geomorphology of fine-scale time slices. This

~ p p r o a c h would establish the basis for strati·

graphic

concbtions.

...

bal

soon

1

wu

ton:ed

to

successi.ely

modify

tllese (l"hunnann"sllaws oceonling 10

1hedivme ..,.

giofts

which

mob up

tho

SoleureJura.

and tho

study

of these di.....w re¡;on. neccssitated on my p:>n

•

s _ . o raeon:il ~ melhodl díl'remll lO the

:BrocU $

used in lhe 1,..,.lation eilher lo lve

tho

Fronch-

tr:lnSiated..

:as on [""terr:lin

l. ur

10

dor·

ify •

nnslaion

in

on1tr

tiW

we

noc

s

ny

too

for

from

the liunl Frenc:h.

ond i

tolics in l

he

lr:>Mio·

non are

ltom

1,jressly.

one

wh

ich is e n c n l l pntettced e ~

ni

bdn 'J

li;,1lJ:St'ied \\'ÍÜ'I acenut - .nbt r 01 \'fttK21 ;¡_

type secuons ('1ypesdtscnpti

fs

"l. 1followed e.xh

u ~ h

um1

lbe·

uoml

ulon' us honi.OIItll ertent

as

r·or a.<

'O>Sible

'

order to 111udy oll

il<

,..,a1oom. 110/21- ;91

In these JXISSa CS Gn=ss

ly

recoomed his ch:lng

i

ng

perceptions abaut the aPProaches and

phihoophies requircd

10

study thcslflltigrophy

nf

the Jura.

He

in ended

10

conduct

t f l l u g r . ~ p h i c

re

sean:h us

in

thcex istinc

par: digm a.nd

methods.

but hediscoveted tl\31 theydid not

worlc

and werc


4/14

paua, . rom

one

paleontoiO@icaJ assembla@e to

aJ10iheralways o c c o m ¡ ~ a n y hose petmgraphic tran

siúons.

Io.,

renect the physical

and

chemical

M t r i b u ~ < · ,


5/14

,

-.

-

..-.

ru n .¡

.... MI.U

u c

omposiUon

a Ílllftr.

Ocwl»t4J

.

l laildanlbonksond ....m

. . . . . . . . . . .--10 danpous to

ships.

These

oJways..., . . . . . . ..ied by - orpriÍ$111S

to

ccnl Mis. which IJII'"I'to

Hourish

in

nretr.· q í u ~ Wllcr. dius

always IMnJ

•

tila P">•idcs tei Wiee ID lhe

WIYes.

IR a irWy fi.Ud10 i e ~

die

0111-

h:lniJ•ccaaak

l

'f elastic sa\ICNI'e

whic:h @'iws

- in ie

force

of he waves

rewwen

•aly.

and

comes

CM vicloriouo frnm

die

comlill.

Tire eltemal JniRl'III"' Y of tht

ta

. . .

die byouc

of

rhrir

orpns

are no

leu

wtHd\ poet f t

th rtt

Comr 'IDftly

all

these popea;u

oare unned

ladr

lre objec.oc. ll312: to 141101

odler ~

he compared fossil mor

opcs

in dilremrtllabitats ond related the

of specics (communitiesJ in thesc

to nu¡Aa¡logic :ldaptation to

he

phy•i·

chemiaJ conditions of die respecti

ve

en

auts.

lnlbeC3SC of

muddy

hmitats

citcd in

followiq. Gressly obst:t

>ed ttw

gener:1

and

ies or

tire

fanal assembluges have thin.

l e s s - o m : ~ ~ e

shells

tha1

are

not

e s i s t : ~ ~ ~ t t o

.

,_..¡

nc. whiclr is COIISUJII for all p:rleontJ>·

o die muddy a e ~

1J

thM tire

1ct1Cf1

ond

$pecies hove tests less

apt

etfeas of ••-ndn8. Tire shtlls.

.

odien. - rrcrmally >ay thin. -ay 11111Ch

• lesCIIftllle..kssOi&taadwimdiffamc:

1 ao:es

l ira

in die preced

inr

(coral( f:rdes

- drey have 1 >ay p CRIOOinced

IIWSt\1

. . . . , ,.

Ko•e>CI'.dieft""' somelimes senen

sp:áes """" _ , . dlidr. shells bul whiclr have •

oboost sowcrwe and which

eu

ily ddamina.t<

t ·

._

¡n:¡wbyabiuion.

al814-

ll)

developed and illustrated scvem niche

uu¡AUop: "'II(•OIIioiiS orspecies10 their

as illustnll:d by the followi ng eltllmple.

Onc ''ftY

;;npu;

wa

C'hlra:aeabtie which is univenal

ro

CllpliÍSIM widlin

lhe ccxal

facies

is

a very thlck

WJI. oiWI)'$ hi¡l ly

otnllllftlled

by ribs. Slrillions,

' P"ftn· nodes. ud other

m a ~ M n m i o n i

>t

tnt: .1

~ i : a f pn)"MMDUmV, \c: f"Y u·t q U I';u"

_

____

.

. ........

........

.. ,

..

....

....

.....

.....

.

..

.

........

..

. .

.

an ocean Ion.: oe lrom thc surface ot' the t:vth.

1 5120-26)

-

roomen

ts

rn

wmcn

mcy

cx:cur.

regarure

ss

or •ge.

ESTABLISHING THE CONCEPTS OF

VERTICAL

FACIES

SUCCESSJONS AND

LAWS

GOVERNING LATERALAND

~ C A L D ~ U T I O N S O F F A C I E S

Having esrablished the genetic relation be·

rween

facies

and

deposilional

environmenlS

. :111d

having equated

he l : l t e r . ~ l

vllriabiliry of faci es

alon&

beds

of ire same age wi llthe mosaic of

~ i t i o n a l

environments along deposi tional

profiles. Gressly considered

tire

dyna.mics of the

geomorphic process-response system through

ñme and extended thesc

re

lations into

the

four·

dimensions of stratigraphy. He established llat

tire regularpmems and trends of fncies observed

l a t e r . ~ l l y along beds were replicated through a

venic:al

succession

Df

beds. Moreover. tire veni·

cal succession

of

fliCies through a series of super·

posee

beds

wu repeated within larger scale

stratigtUphic

unilS.

The regular venical succes

sion ot' facies

wu

accompanied

by

a

: g u l : ~ r

suc

cessi

on

of

f

os

s

il

s.

~ s

expl

ai

ned these

si

m

i·

l

:ar

venic:ll and l:ua:tl ~ m e n l S of facies :111d

t

he

o n t r o of their distnbution in the fonn of

five laws.

Afttr ~ v t n deunn

ined t

he

ma

jot f

ac

ies which

t n : ~ our ~ terr.un.s• it

renw

ns to t

ü e 3

look ot t

ht

ow<

whiclr

underlie ondcontrOl tlreir

dis·

lribrt ion bolh \1 1ticolly lUid honzonwly. (2

00

2-lSJ

Gressly' s first law that facies change

tr:rns

i

tionally wi llin

coeval

beds is

as

f o i l ~ :

Ü


6/14

fnd-mtmlwrfa.citl. mokCI

it

difficult to lrfHJNit

r l r t m . l ~ l J l

Gressly's founh law is

as

follows:

Dil-trs-lr, of

W fod l 'tC'mJStl

in

a

\'t ical dirw-

·

rion

fmm x u ~

ro

top throuRhnur tht

K

hol

e

Stl'lt

S

(str.Jtipllphie

succession l l u ' o u ~ h

he Junul s u b f ~ c i e s . which

vary

in he different 5tr.ltigl'llphie uní . llnd reg iuns

ofour Jur.L and whie

.h""'u>eful

toknow

inordcr10

undmtllnd

he laws of distribu1ions

of

poleontolog

·

ical

A ~ i a t i o n s

These

~ u b r o c - i

nre eAplained

:at;

t r : ~ n s i l i o m . which

link the mljor

facies.

lltld

allow

•PI"eci

otion

of

he

slightut

ft\WICCS on he

livínJ

condition•

of

the or¡anic

world

now buricd

in

lht

e:111h 's

cM . Thus

c

oquinas

link pctrographically

thc purely

coral focics

lo

he

p u r e l ~ m u d d ~

fx í

cs .

p a s s o n ~

throuth the

oolíths and pi:101iths

.

to

he

. . dy

and

gra\'C:Ily

varieties (mi"'uresJ

of

thc

mudd

y

facies

.

Analogoos passages from on

e p.ale·

ontolo¡ico.l

asscmbla,e 10 anolhcr

olway< aecom·

pony l

heoe pe Jo¡;npitK: tnnslliOM. le

rs

alwoy< the

moSI

deliate o r m ~

which dominate 1n the tr:lnsi·

tion zones. (IY27

to

1617)

'

\\ lo>t

1

have

said

about venieol ' ~ o n of

facies

15

not

withou1

excepllon.

and

it

is

obviously

nac\li'IJ

that this

bw

should vary

occordint to

he

pcuo·

""ploic and

geogr-ies of oo:ks

and s nli·

;nphic units. We

sho

uld thus nnt be

u r p n s ~ d

10

liod

withina

mudclv roek. ilbcweor hc low acur.Uline

roo:

k.

fos.,ls whic

h.live

in

mud.

But hese f05Srl> of

he

muddy

facies

will indK:ate no less

thonthe

cor>ls

:s \h:lllow marine

or liuoral i r o n m e n t

even

t h o u ~ h ~

roc:ks

are

of a dlffcrenttypc

:x:conlon•

h> lht lr ~ u u o n - 3 J

proceu.

C

1

/) J cu

~ : 1 6 1

.-\brupc fac-ies tr.Ut\ilioru

~

JWticulatly uhv1ou._ ht ·

I\\C

('n c

tn.l

o n u ~

f ~ :1nd purt

mUW

.

in

somo

e>ses.

fo

llowinl •

con

sider.able

(thick ond lat.enlly

uten.r

vel

pc

l

a1

oc dcposn. lit·

un l rocíes appc:or >bro¡ltly. almost

wi11oout

any

plduoltnnsnion.This

phenomcuon

.

allhou1h

in·

frequtnl. once osain hc

ins 11 he

I..Dwft Oolite.

h

coincic.les

with

he abru¡M or parhql hontonlll

f ~

tnnsi

tions

of

he t ' l l i ~ i c :

Un

liS

. . . . c:h

1

porntcd

OU

t e \ ' I O U S i y

l 2 3 / l ~ l

With his

fi

fth low. Gressly applied the mher

four lows

to

reconstruct paleogco,ruphies

throuph time. For ~ u c c e s s t v e time tntervals he

d i s t i n ~ u i s h c d three f3cies tr:>cts

("zo

ne"

and

"band"l: littoral. pclagic. ond

b p e l o ~ i c . and

he

m:apped

thcse ov

er

o wide

orea

from the Vospes

and Blacl; Forest in the

nonh a l o n ~

the Rhinc

nonh of Base . Swi tzerland), t h r o u ~ h the

Ncuchotel Jura. to the Sovoy subolp

in

e 1 ~ 3 in

thc south. Gressly reco@n i

z.ed

that facies

di>'ef

sity incrcascs ~ g u l a r l y

ucross

this

l"ef ion

from

thc

pclosic

f:JCics

1roc1s

in thc

~ U t h

throol h the

subpelo ic. into tite littOI'lll focics lruct in the

nonh.

and he esmblish

cd

that lhcse faci

es lr:IC s

m:úntoincd appmxim;uely

co

nstont geogruphic

positions and widths throughout the Jurussic.

Tbe

fifth low

is

st.lted a.<

dit-rnin·of ncin

is

m o r ~

or

lc

s.t

nm s

tanr m

diff'r'nt

r< Rinn

.t

facies tracts).''

(2317)

One tou

ld

draw oline s11non, fmm Randen .. .

'"far

a1

Ch>t

elu .... runnon' p:orallelto he foot of the

BL.:k Fareslllld he o s ~ which

would

divide thc

linotal facies

and

he

foáes almost eucdy

into two

s e p n ~ e ponllel

Jurassic

zones

. Tbe wc I o n ~

beds and

venically

tl'roulha

ICries of

bc<

is a dcscription

of

l a t i o n s amonJ

d e p o s

t i o n

er t

in

owmw:nu.. their distribution aloft a depos

tional proftle. a

nd

t r a t i l f : ~ P h y rcsulting fro

p r o ~ i o n

which later

bec:amc

known

w.Jdlcf

'

s

Uw ol

thc

Colft

l:llion

olf'xics. In :

odlerpan of hc Gmsly

funtler

develop

thc

idea

of

thc equivalency

e t w e c ~ ~

the late

clistributíon

of fxics Ilion

a

a

bcd Cdeposition

profil al

gcmrne

..,..¡[ DPhio:

'*'.udo as

hekno

•••nor«. he

l1IQ3IO

d i e llaculilosl

\

ucllly

,.-ilh

in

he r g c r litho .cr.lltVo'Pitic: un

1 1 1 1 : : 7 - 1 ~ )

"Jlus, ll(l(

only

didGreuly

undmW d

IOICI'lll

succession

of

facies

along

a

rlepo5itio

prufil<

was

~ c d veniallly through a s

rn

ol

becls.

but he undenlood that f o n i l ~ hall t

fund4menlal uses.

Rnt

. some

fm

sil groups

flect

he envtrouments in

whích thcy

INe. onc

¡:.nicul:uly uscful in paleoenvironmenul ín

p r e t ~ t i o n Second.

other fossil

,roups oc

cu

specilic, limitcd str:ttifTllphic inlervals.

~ p:uticularly uscful for bíom

gnp riccom:btion.

Gressly

's

observ:ltions about the \latieal

lan l n :l:llionsllipsof facies.._ almost irn

t.liately adoptcd and rxploitcd.

u l m i n a t

Wa lt

heú

118941

reexplanation

of

thc relat

ships and his

diseussion

obout

how

that infor

tion

could

be applied

in

stratigraphic com:lal

By

contra.st. as

n01ed

by Teic

hen

f

19

Gn:ssly s

obKr\'lllions

about

thc

two

uses ol

sils

were

noc.

incorporared imo common prac

G r e s ~ l y c o n t e m p o r u r i e ~

focused on the

f1

ond

p o l e o c n v u o n m e n ~ l ~ p p l i e 2 t i o n s of

fos

and a more prectse dcvelopmenl of b

io m

~ p h í c

•PPiications did

n01

occur unlil Op

worit

in

thc

Gressly Slressed the ••olue

and

•Pf licauo

palcontology

on

bolh

co

ntcxts for two

reo


7/14

· ~

10ward

the study of sedimen

n

the

:Jbsence

of

a l e o m o f ~ o c l l l

in·

wu a su::nlt scienct. Second. he ftlt

h ~ s i c : J I and Oiologicol appmnch

and corrOOonttíng ínfonnatíon.

m:lde

ínt

erprelations more robust. After

untíl the

tnd of

the ctntury. biostnt

ll

·

applicouons dominated s t r u u g r a p h

In

se. Walther tl894\ h3d a reacuon "mi ar

oi Gressly: helashtd out OJ: óllnst tht

•m

·

use

of fossils onfy for biostraugruphic

: jusi

as

Gressly had re¡ected the om·

. soltly míntralogical approach

10

the

Str.lta

on

his nme. Walther insisted on

ap-

dtt:llled infonnation about

1he

physocal

ni stntla. t•panding and

m p h a s i z i n

the

tim cnunciated by Gressly.

AN APPROACH TO

I

GRAP

HICANALYSIS

conduded the tirst p

31'1 nf

his paper

by

t :>dv:tntages ofhis \lraugraphic ap·

in four points.

simo

lofie

s the apparenl complc•ny in

and pro

vodt

s a coh

eren1

link he·

palcontolo¡ ic:o.l and phy


8/14

popul:lri1y of m and n c e < m u i ~ -

ti:tted by Peter R.

Vail"s

group al

En

on

.

1'>71

).

or FllciesTr.ct Movtments ~

v : a l ~ n t

to l r a t i ~ t r a p h i c Cycles Delined

\"ertical SucctSSions of Facies

is bener lmown 1oday

fo

r bis ··uw of

Correlalion of

th311

he

os

for express

the requirement thol moss is coMen·ed in

ss-response sys1ems. This is

to Middleton"s (

1973)

account of

hc

r"s

work. Middleton foc used on Walther's

of the relationships betwecn ' 'erti

facies successions and lateral facies lransi

= equired geometrically by sedi·

ccumulattnn on an inclined surfacc.

tha1

ts.

. Huwever. Midtlleton did out dwell

the omponance of tbose relatinnships on the

text of str:mpraphic correlation. "'""" though

was wnhin this strongrap

hi

c con

tex

l that

he r cnnsu

uc

ted his law.

a<

was emp

hasozed

hos tille. To understand Wahher's insistence

the need to fnrmulate such a law tor 1he

se ot 1 r o u p h i c correlation. we '"kw his

f

ro

m

a

historical context.

Walther

fi

rst restated Gressly·, ob,en·alion

t the uescriplive. physical auributes of a roek

' f a c o e ~ ' l reOectthe pro«"are tn the po"uon 10

widen our knnwleuge.

"'

Finally. he not• d that

e\

en u n c u n f u n n m e ~

:md other

(,urfaC'C's

ot

\t

rall·

~ r a p h o c

d i ~ u n t t n u u y

nnly help e$tablbh relam-c

ot rock

unus rattler than true temporal

of correlatton t l 8 9 ~ . p. \183 t: "when

a

1rnn

syressmn rrom a p o ~ i 1 sho reline

t t n O \ ~ m e n

vt:Tt

i


9/14

is

ru ll

)

oo>

pn:setllfd in the str:ltigrnphic

by che combiru11ionof

nxks l u ~ r f ~ c e 1

k olisc\•ntinuity. Tbe

ume

rcpre·

bi

gn

11111.'\lrioorm

uy at01to ~ o c po-

i.' tCjMC W111cd by rock

31

: a n o ~ h e r fl. but

primanly

in

~ ' C U m o r p h i c

1h:ln

l n i i ~ J p h

cnntcxts.

~

l l ' s

nouun

1"31a-

NWrall

ydivisible

11110

str:dcgr.¡phic

h:lt m:mlthe nsc

3lld

f:tll oi b:be levcl

~ i c s wcnt r K . i u l k n ~ c l l .

unmO>.

,¡rotigr.¡phic

trJSC

lc-vcl

:11.

1

1

onph

cc-:U

1.

noohurizuntal. u

nllu

la·

C l l n t i n u o u ~

.urf:u:c t

h31

riscs and

f ~ l l 5 Wll

h

the E:ml,.un":lce.

As

base le--el i ~ < .

uf

thc

t > a . , c · l ~ e l

>wf.'lce

and the

Eanh\

.un':¡cr mo\-e

upholl

.

oncnoa.urtici:ll p r o ~ that b r i ~ stdimem tu ur

\'c Cdimcnt fmm that spxe.

In

effccc. but

~ p l i c i t l y Wheclcr olclined s t n t i ~ r J p h o c

tr.1.'1e

as :a pocenciomecric cner;y

'urfacc 1 h ~ 1

ribcs thccncrgy "" Uircllto

1110\ e

the Eunh \

up

ow

o.lown tu a posicion wflcn: grJdicnl U c c e ~ s o o n s . li

thologic dh·crsit y.

't

r:lllticacion t

)'pe>

. and

p e c r o p h y

s i c ~

anributcs

of str

aca

which :ue prescrvcd within illrntical

cio:s tr:x:ts but

on

different ponions oi

b.'ISC·

Iev-cl

c'Ydes.

Tbe cfrm ""bcoC1differentiacion" relers 10

thcse changes in

stdi

mencological añd scrati·

graphic ~ t t r i b u t c s d u r i n ~ b:t\e·lcvel cycles. Fa·

cie.' diffcrcntoation retleccs the degree

oi

presc

r·

vation uf original gcomorphic elemenls.

as

well

as

the \"ariacions

in

types of geomorphic ele·

ments

th:u

cx ostcd wnh in a depositional environ·

mcnt

dilfcrenttomc

s.

Thcrcare rwo prindp:tl c:ucgorieso facies dif·

fcrmtiation.

Tbe

tirst e.ncompasscs

che

h a n ~

in

anributc.

of

s i n g l e t h ~ t occurduring b.'ISC·

~ e l

cydcs. The

depo as:.(mblages

retleo:t

changes in

c

he g ~ ' O m o r p h i c

con>muents

uf

thc depositionnl

cn\'ironmcnc. A

c"Ommon

cx:unple is lhe allem:l·

1ion of wav c·llominated. open-ocean-facing

shorcface.< during base· lt:\·el f ~ l l . with

tid:clc'Ur

·

rent

olominacrd

open

bay. ~ u l f . and estu:uy envi

ronments

oluring ba>e·lcvcl

rise. The seomcxpllic

clements occur altemately

atthe

s:une position

along thc topogr;¡phic dcpositional prolile and at

thc

s

ame

r o ~ ~ ~ g

in water deprhs. Essentially. the

open-ocean-facin@ wave-dominated stn ight

c ~ l l i n

is

tc

mpuruily

n:p :ll.'ed

doring times

of

base·level nsc

:uod

incrcasing :x:comrnodation by

an e m b ~ y c d coastline. when: wave energy is

dampened :uod cidal cu n-cnts nn: enhatlced.

Thc

dcgrer of prrscrvJtion is n conscqucnce of

the

ratio

uf

IICcommod.tuiun

10

stdiment supply.

Setlimentvolumes and geomorphic elrmcnts

=

""'"'completely pre;ervcd u r i n ~ b ~ s e · l e v t l r i ~

when accommod:mon s pace

m c r c ~ s m g .

than

during base·lcl'el

fall

when accommoolan

spacc is dccn:zmg.

C o n . ' C q u e n c chcre

are sp

cilic :me distincu,·e str:lli

@r:lp

hi.: n ~ t u n : nfth

olilfcrrnt

p31tSn

i

b.'ISC·Ie-

·el cyclcs. lbe -cdimc

•olo ic and t r : u í g r : ~ p h

attribute:<

nt facies

trao

commonly describcd in "facocs

modeb

.m

"depositoonal system m < X I c l Jre h u ~ mouur

of l l r i b u l e S which > t c d '"P3ratelv

d u r i

ba.


10/14

considered 10 h.ave a high infonnalion content

a m U ar. predicuble S1IUCI\Ire. Quantitative

í:

nt

s of sedimentoiogtcal. btolo¡pcal.

pcii"Ophysical

aaributes sbould provide infor·

crucial to unnveling lhe complex ltistOf)'

scdimenwion. E.wnples

of

sedimentologicaJ

10

measure indude bcdset thiclcness of

cal typcs

of

cross srratification: bedform

frequency

of

shale panings: frequency

:unount

of

relief011

scoursurfaces:

;)lidciegnle

preservati011

of

ori@inal

geomorphic elements .

of

·biological allributes include

miao

composition: faunal

si.u:

: spccies i ~ i r y :

of trophic levels: and

reprodu

ctive strat·

of

popubtions. EJtamples

of pcuophysical at·

porosiry. pcrmeabiliry.

and

capil·

emry pressure. Recording of

thesc

aaributes

a time frame given by

the c h a n ~ e s

in

should

provide

a

clearer and cc.

p1crure

of

he deuils

of

t r a t i g r . ~

Amanz Gressly

began

geologicallield studies

the

Jura Mountains with lhe imention of map

g and com:lating strata and reconstructing

paleogeog l llp/tiCS within lhe ex.isting

igm

of

Wemerian

N r ¡ ~ ~ u n i s m .

His careful

causcd him to recol ftiZC the

invaJid·

of the

tenets

of

parndigm. wh icb he jeni

of

the

parndigm

we have today.

Gressly established lhe

following s t r a t i ~ p l t i c

cipies. ( ) Scdimemary

fac

ies record the

and conditions

of the

environment in

ich they accumulatcd. and are interpretcd by

with

modem

environments.

12)

Severnl

cies coexist at lhe same water depth and may

erefore substitute for each Olher as scdiment

through time. (3)

The morpbologies

fossil species reflect lhephysical

and

chemical

of

their

habitat. but nuances in their

reflect cvolution. (4 ) ~ n fos

are more u

se

ful for interpreting

the

environ ·

ent

of

deposition ("facies fossils"

).

whereas

are lliOI\ useful for establishinl lhe •

of

t n u i g r a p h i c unit ("index"

or

"zone'' fossils).

51

T i m e s u u t i ~ p h i c su

ña

ces an: defined by

s that follow adepositional profilc .C6l

Facies

transitionally in a unidirectional trend

depositional profiles.

and

this trend is re

c a l sequence through a succession

beds ta worlúng descnpuon

of

W a l ~ s

). (7) Suatignaphic com:laüons based upon

equivalency are dcmonstnltcd invalid

the

= h e

studied Cand by extnpolation. this

10 allcases 1 C8l Str.u i

pphic

o m : l a t i o n ~

be bued

upon the

time equi,·nlency of

r a p h units. even if their facies differ.

The depositional profiles and regtonal

faci

es

CROSS ANO HOMEWOOO

trends with

in

a limited strllip:lp/tic interval de·

fine lhe repional

p a l ~ ~ t a p h y .

Gressly providcd the shou lden upon which

ocher ,;ants

of stratigrapltic scicnce

have

stood.

After G

re

ssly. lhere were five additional strati·

~ p h i c conceptS thal

were

added to complete lhe

curmtt stnúgraphic paradism.

<

l The

stnú·

gnplticprocess-responsesy

stem

conserves ma.ss.

(2}

Sediment volumes are diffenentially pani

tioncd imo facies tncts within a spce·t ime con

únuum as

a

consequence

of

mas

s

conservation.

(3}Cyclcs

of acies

tr.ICI mo>eniCIIS lalaally(up

hill

and

downhillliiCI'OSS lhe Eanh's surface are

di=tly linked 10 venicaJ facies suc=sions. ;¡nd

are

the basis for high-resolution com:lation

of

sb'llligraphic cycles.C4l Stntigr:sphic base level is

lhe

d ock

of

geo

log.ic

lime.

and the referente

frame for relating lhe energy

of

SJIICe formation

wilh the cnergy

of

sedirnent uansfer.

(5)

Facies

dill'eremiati

on

is abyproduct

of

sedirnent \ Olume

pllltitioning.

Mo

st of these concep1s were added

around

lhe

rum

of he

century

.

ACKNOWLEDGMENTS

We th.ank Jean Paul Schaer and Marc Weid

t1WIII

for

reviewingour

tnnslation

of

Gressly and

for considerable insight

011

relevam historicaJ

;¡nd

biograplúcal

manen

.The

ir

shzed enthusiasm for

this subject

was

stimulatin&. Michele Aldrich.

Gerry Friedman . and Gerry

Middle1011 provi

dcd

constnlctive reviews and direacd our :memion

10

sorne

of

the relevan literature. Jolm Grottinger

read the pcnuhimate draft and s u g ~ s r im·

prol'ements

in the presentation. We

a ~ a t e

their help. Elf

~ p l o r a t i o n

Product ion

gave pcr

mission 10 P. Homewood to publ

ish

lhis papcr.

API'f:NDIX.

TllANSLATIONOF"CEELLGICAL

OIISERVAnONSOFTREsoutrRE rtlRA."

PilRT l."llf'SCRJFI10N

OFTEJUtAINS

WHJCH

COMPOSE1HEF RAMEWORK OF111EJVRA

RANCD IN1HECAHlON OFSOUUREAND

ADJACtNT REGJONS"fGRESSLY. 1

1311

The mounainnn,. . whidl run

tJwouab

the

Soleoft

Canton Md all of northwest Striuer Md

are

com

poced.

as

in

the French

Md Bcmese JW L

ofaltcrMt·

in

l hlrd and nonresiuam li

mr- .u

llld marb which

cOftlaln minor

bedl

of silictous. iro&-rich.

and othrr

monenb. The number of strlti@BIIhic unns rqft·

~ y

thesebeds

S . .....

~

t h e

nonll

of

he

e

llld

in the ad j aceM- of

Aflovia

11111

Bloel

J

tn . rlwl in the ra t of the Svms

Jura. Besides

the

variousoolilhic: p:roups. olderstntipaptric unnso(

the Triusoc fomwion OIJCCniP

.

show•nr sect lOM

of

lhrir tihed

beds.

Thete upl ifted stmiftl lhic units

in

tlúsara

comprise

the wholekWiidlo

y(

Wemer·sS..:·

andary. or stnliflld rocksl seneo fnJm the

'-.rirpltnp 11 foil..,..: 1 1 ) - 1

l.

r l G , & or

COitC Itylr

mtt

F'orwt.tJ

tlnll.

n

WPfpn•in

.r

dtt oil

'

"'

l.

Variegated sandslone temin

2. or Musdlelbllt

J.

l f a o p e r - or a ideaL••morh

ll.Jwtwlc0<

(ÑI/tf l iL·ÑJmtaiiOn

AlÜIWic

C..,.

subdi •icled illi M

Nt

we

IR cuw::a•a:d wutl

becausc

it pr'O"des

""-'ee' J i

. ; . ; . . .

wluch

ore. . , . ,_

lld

awids

s

ubdn-nions

tiW

1ft onificW

Of

purrly local. lt

11

..... UOIO brift, out

~

rnrOIIercumplu desci i

pd . . . .

sifiraion) the essential charxurisrics

of

ow stmi·

plllhic

1lftiiS

ond their i a l rebóoftlllipo W llll..ao,s

r.- I'


11/14

how

tMCh

lhe tNC'ture

of

ovr Jura is srill u i W : . o w ~ t . .

fiCU wtlich Wlf lo ,N IWW ' C * J I O ~ i c a J

ai'Mi whol.c rcxh • UI the . . .-_

. . . . . . . . . . . . . . . . . . . . . . . i..UC- w

~ Md btftdt

m

fOI"a: of

tht

w.ws bit uoY

iee«•• owty. Md C'OmiCt 0t.11 vk'eorion rmm th

~

mmbtt,

11w:

t.rtla'ftll

h U

. . . . o/ hc

....,..., .... ,.,....ottoew.._. . ., ..._

pn. ro thr

citc:UI'M4 NK'C'S

wtlich pera

.,.; ,-..

c-. . . .y 11 _ '*'

..

unio

-

....

olljlt

- fised otojoca. . . . . . . . . . ""'c.v..

....StooedJWd& ~ ...... - """Oild. ""

...........n....-.

_..,.__ltdp.

dlor-"'_......., 0111


12/14

llld

. . . . . . . . ...

, . l l l d

,-11)'....-

,

.....

twrs

)ol thc......., facirs. J:MI IOIJI ....... fn:a

( JM pakoe 101

.....

•. . . . o IIIC'JIMr...., eo

~ y d l c & p s . . . ¡

''

•• . . :Lkil...,..lhr:

-dd

i-l"p . ...---·

dio......--.

IS/27.,1611)

Rowofttd dqlooiiJ.

_. , . ....,

n:llillodl

liollylto thc conll . ._ _ tllctl ,..,.

_,,

come

. ac-y ad liok oll1be

l e d o ~ . llld doa

"t

_

,...,_,,..._.,

__

_

k»ooc

,

. . . , . ._- r twaaeriscic

e •

ait:al s ~ m ~

~

l'hty . . . . . . . . W::C:OOdiac iOci

iC

WI kW11t

"'diln. . - . l_ . . . . . , . . .uol t thow

,...m. .___ ,_ ,_

. . . .. . , ...... .-

. . . .

o....myliodo

'

. .

l i k , _ . . M d ~ -

....,,_,..,.

...

___

- . .

..

.....,. •

wry

"M:at te r wt.en n 1anm

.er;..,m.

1ft

fW't':,

JPftad

out.

aad

bdon1

. ,

moedy to

free..

livina

f a r m . ~ . &hinoduu¡¡. e Mtlrln1 rwe in,.,._..lhr

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Amanz Gressly's Role in Founding Modero Stratigraphy

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