[ P r o c . R o y . S o c . V i c t o r i a , 5 5 ( N . S . ) , . P t . I I . , 1 9 4 3 . ]

A r t . X .— E o c e n e D e p o s i t s S o u t h - e a s t o f P r i n c e t o w n , V i ct o r i a .

B Y G E O R G E B A K E R , M .S c .

[R e ad 10th D ecem ber, 1 9 4 2 ; issued se p arate ly 1st O cto b er, 1943 .]

Ab s tra c t .

D epo sits o f E o cene age are desc rib ed fro m the P eb b le P o int distric t, so uth -east o f P rin c eto wn . on the south c o ast o f W estern V ic to ria. T he f o ssilif e ro us “ P eb b le P o in t B e d s ” have b een estab lish ed as o f E o cene age f ro m the evidence set o ut in the two f o llo w in g art ic le s b y S in gleto n and T e ic h e rt respec tive ly. T h e O lder T e r t ia ry sedim ents o ve rlyin g the E o cene P eb b le P o in t B eds, are ten tative ly re f e rre d to the E ocene, pending the o utco m e o f f urth er f o ssil in vestigatio n s. T h e relatio nsh ip b etween the J urass ic ro c ks o f th is distric t and the E ocene ro c ks is desc rib ed,' and re f eren c e is m ade to M io c ene beds ap p earin g in c o astal sec tio ns s ix m iles

n o rth -west o f the E ocene depo sits.

I n troduc tion .

T h is paper deals with the o c c urrenc e, n ature , and strat igrap h ic al

re latio n sh ips o f L o wer T e rt iary depo sits expo sed in c o astal c lif f

sec tio n s b etween P eb b le P o in t an d the m o uth o f the G ellib rand R ive r, in the p arish o f L atro b e, co unties o f H eytesb ury and

P o lwarth (f ig. 1 ) . T h e b asal beds o f the series, c o n sistin g o f f errugin o us sedim ents, c alled the P eb b le P o in t B eds, are assigned-

an E o cene age f ro m independent fo ssil determ in atio n s m ade by

D r. F . A . S in gleto n ( 1 0 ) , o f M elb o urn e U n ive rs ity, an d b y D r.

C . T e ic h ert ( 1 1 ) , o f the U n ive rs ity of W estern A ustralia, on m aterial co llec ted b y the auth o r in J an u ary, 1942 . B eds o f c lay an d sandsto ne o verlyin g the P eb b le P o in t B eds, are pro b ab ly

also o f E o cene age, b ut th is has no t as ye t been c o n c lusively

estab lish ed.

P eb b le P o in t, which has a N .-S . trend, is 2J,- m iles so uth -east

o f the m o uth o f the G ellib rand R iv e r, an d ap p ro x im ate ly 3^ m iles so uth -east o f th e to wnship o f P rin c eto wn , whic h is situated on

th e so uth co ast o f W estern V ic to ria .' I t is m ade co nspicuo us

am o n g a num b er o f sm all h eadlan ds h avin g s im ilar appearan c es

b y the presenc e o f a m arked sto rm -wave p latf o rm c ut in the E o cene ro cks ab o ut 25 f eet ab o ve lo w-tide level. A djac en t h ead­

lan ds h ave wave-c ut p latf o rm s in J u ras s ic ro cks. P eb b les of.

jasp e r, f lin t, rh yo lite , q uartz ite , and agate o cc ur on the sto rm -wave

p latf o rm at P eb b le P o in t, and a pro m inent b each san d-ridge o ccurs

in the b ay im m ediate ly to the so uth -east. I n th e P eb b le P o in t

d is tr ic t , th e E o cene depo sits rest upo n ero ded J u ras s ic ro cks (P I .

X ., f igs. 1 an d 2 ) on th e so uth -western f lan ks o f th e m ain. J u rass ic

are a in the O tway R an ges. T h ey ex ten d eastwards f ro m P eb b le

2 3 8 George Baker:

P o in t at h eigh ts in steep c lif f s which are p rin c ip ally beyo nd reac h ,

but in a n o rth -westerly direc tio n , the series dips ge n tly at 5° sea­

wards, so th at f ro m P eb b le P o in t to with in a q uarte r o f a m ile

so uth -east o f the m o uth o f the G ellib ran d R iv e r, o cc asio nal ac cess can be gain ed to several expo sures o f th e L o wer T e rt iary de p o sits ;

m an y p arts , ho wever, are m asked b y c lif f deb ris. T h e ap p ro x i­

m ate th ic kn ess o f the L o w e r T e rt iary series b etween P eb b le P o in t

and the G ellib rand R iv e r m o uth is given b y W ilkin so n (1 2 ) as

2 5 0 feet, an d o f th is am o un t, the P eb b le P o in t B eds o f E o c ene

age to tal ab o ut 50 feet. W ilk in so n ’s value was o b tained b y

to tallin g th e th ic kn esses o f the strata at th ree dif feren t an d re lative ly w ide ly spac ed c lif f se c tio n s; a series o f b eds dippin g a t

5° and o utc ro ppin g O ver a distan c e o f so m e 2 m iles, h o wever, wo uld have a to tal th ic kn ess o f o ver 1 ,00 0 feet.

T h e gen eral geo lo gy o f the P rin c eto wn are a is indic ated on th e ac c o m pan yin g m ap, wh ic h is b ased upo n S tate p arish plans in th e

so uthern po rtio n o f the co unties o f H eytesb ury an d P o lwarth .

F ew surf ac e ex po sures o f the J u ras s ic ro cks o ccur in . the are a em b raced b y the m ap, an d then o nly in c lif f fac es an d on wave-c ut

p latf o rm s at h eadlan ds. T h ey are in suff ic ien tly ex ten sive to ap p ear on the m ap (f ig. 1 ) . C o astal ex po sures o f the T e rt iary ro cks are

F i g . 1.— Geo lo g ic a l m ap o f c o a s t lin e in th e ne ig hbourhood o f P rin c e town .

p rin c ip ally ab sent f ro m the plan , b ec ause of m askin g b y co vers

o f R ec en t sand dunes, P o st-M io c en e c lays, and P leisto c en e dune

lim esto ne.

P r e v i o u s W o r k .

T h e dif f iculty o f ac cess to the are a 'an d the rugged c h arac ter of

th is lit t le f req uen ted po rtio n o f the .V ic to rian c o astlin e, are pro b ­

ab ly the prin c ipal reaso ns w h y the P eb b le P o in t B eds an d o ver-

lyin g depo sits have rec eived litt le detailed atten tio n in th e field.

T h e depo sits were f irst placed on rec o rd b y W ilk in so n in his surve y o f the C ape O tway c o un try in 1865 (1 2 ) . F o ssils co llec ted

d u rin g th is surve y, m arked as co m ing f ro m N o. 6 lo c ality b y

W ilk in so n (i.e . — the P eb b le P o in t c o astal sec tio n ), were sub se1

q ue n tly determ in ed as N autilus, C yth eraea, an d C uc ullaea, and

the depo sits were c lassed in th e f ield b y W ilk in so n as M io cene ( 1 2 ) . S o f ar, the auth o r has been unab le to lo c ate the repo sito ry

o f the fo ssil m aterial b ro ught b ack b y W ilk in so n f ro m th is lo c ality.

W ilk in so n ’s results we re re-stated by D uncan in 1870 ( 5 ) , in

h is ex am in atio n o f the fo ssil c o rals f ro m W ilk in so n ’s N o. 7

lo c ality (se e f ig. 1 ) , an d again b y M u rray in 1877 ( 8 ) .

I n th e ir c atalo gue o f desc rib ed fo ssil spec ies f ro m the C aino zo ic

ro c ks o f so uth -eastern A u stralia in 1903 , D ennant an d K itso n

lis te d two spec ies o f T r o c h o c y a t h u s ( 4 ) , F l a b e l l u m ca n d e a n u m E dwards an d H aim e (4 , p. 1 3 2 ), N a t i ca h a m i l t o n e n s i s T . W’oods

(4 , p. 1 1 3 ), V o l u t i l i t h e s a n t i s ca l a r i s M c C o y (4 , p. 1 0 0 ) , V a gi n e l la

e l i g m o s t o m a T ate (4 , p. 9 4 ) , and P a n o p a e a o r b i t a H utto n (4 , p.

1 2 6 ) f ro m a lo c ality “ R ivern o o k.” T h is lo c ality is m arked on

the S tate p arish plan o f W an ge rrip as a sm all to wnship a sho rt

distan c e in lan d f ro m th e co astal sec tio ns in which the E o cene ro cks are expo sed. T h e ab o ve fo ssil nam es ap p ear in D ennant

an d K itso n ’s lists in a gro up c lassed b y them as o f E o cene—

O ligo c en e age, th is gro up also c o n tain in g suites o f fo ssils typic al

<of B alco m b ian ro cks.

D uncan h ad p revio usly desc rib ed and illustrated the fo ssil c o rals

■ collected b y W ilk in so n f ro m N o. 7 lo c ality as T r o c h o c y a t h u s

v i c t o r i a e (5 , P i. X I X ., fig. 3 ) , an d T r o c h o c y a t h u s m e r i d i o n a l i s

(5 , PI . X I X ., f ig 2 ) , wh ile a fo rm with a th in c o rallum

f ro m the sam e b eds was desc rib ed as C y c l o s e r i s t e n u i s

(5 , p. 3 0 1 , an d PI. X X ., f ig. 8 ) , an d it was stated

b y D uncan th at th in spec ies o f the C yc lo serides gro up

o f c o rals are fo und in the N um m ulitic beds o f S o uth ern

F ran c e ( 5 ) . C y c l o s e r i s t e n u i s D uncan (7 , p. 3 6 2 ) and T r o c h o -

■ c y a t h u s m e r i d i o n a l i s D uncan (7 , p. 4 3 1 ) , h ave so f ar o nly been

rec o rded f ro m the O lder T e rt iary beds so uth -east o f the m o uth of

the G ellib rand R ive r. S pec ies o f C yc lo seris a r c regarded as

p rim itive fo rm s o f the gen us F un gia, so th at C y c l o s e r i s t e n u i s is

Eocene Deposits South-east of Princetown, V ictoria. 2 39

240 George Baker

no w c lassed as a sub -genus of F un gia, an d beco m es F u n g i a

. ( C y c l o s e r i s ) t e n u i s D unc an sp. . S pec ies , o f C yc lo seris are m o st

co m m o n in U pper C retac eo us an d E o cene ro c ks (7 , p. 4 8 6 ) .

I n 1904 , D ennant desc rib ed F l a b e l l u m m i c r o s c r i p t u m sp. no v.

f ro m W ilk in so n ’s N o. 7 lo c ality, s tatin g th at it is ap p are n tly restric ted to th is lo c ality an d is ac co m panied b y T r o c h o c y a t h u s

. v i c t o r i a e , T . w i l k i n s o n i , T . j n e r i d i o n a l i s , an d a f ew spec ies o f

m o llusc a, several o f wh ic h are new and p ec uliar to the sec tio n (3 , p. 5 3 ).

I n the sam e ye ar, depo sits re f e rre d to b y C hapm an as “ B lac k beds f ro m east o f the G ellib rand R iv e r ” an d f ro m whic h sh ark ’s

teeth were desc rib ed, were c lassed as o f B alc o m b ian (B arw o n ian ) age b y C hapm an (1 , p. 2 7 7 ) , i.e ., as O ligo cene ac c o rdin g to th e

then c urren t ideas o f the age o f the V ic to rian T e r t iary depo sits. T h e lo c ality f ro m which th e sh ark ’s teeth were rec o rded, is given

as A .W .7 , i.e ., W ilk in so n ’s N o. 7 fo ssil lo c ality. T h e auth o r h as

so f ar been unab le to f ind sh ark ’s teeth in the “ B lac k B eds ” at

th is lo c ality, b ut n um ero us ex am p les o cc ur in a sandsto ne band in terc alated am o ng th e dark-c o lo ured c lay depo sits at N o. 7

lo c ality. T he fo rm s iden tif ied b y C hapm an are O d o n t a s p i s c u s - p i d a t a A gassiz sp. (1 , p. 2 7 6 ) , a fo rm stated to o ccur in th e

E o cene and M io c ene ro cks o f E uro pe an d N o rth A m eric a, and to

have a tim e ran ge f ro m U pper C retac eo us to M io cene (1 , p. 2 9 0 ) . A n o th er fo rm , O x yr h i n a m i n u t a A gass iz (1 , p. 2 8 3 ) , is said to

o cc ur in the O ligo c ene o f N ew Z ealand. T h is was sub seq uen tly

desc rib ed as I s u r u s m i n u t u s A gassiz sp. b y C hapm an (2 , p. 1 3 1 ) ,

b ec ause o f pre-o c c upatio n o f the gen eric nam e O x yrh in a b y

an o th er o rganism .

I n 1923 , P ritc h ard stated th at the co arse grits with ab un dan t

b ro ken and im perf ec t fo ssils east o f the G ellib rand R ive r, rep re ­

sented a sh allo w w ater phase o f the lo wer ho rizo n o f the J an -

juk ian (re garde d then as o f E o cene age b y P ritc h ard ) , an d th at

the predo m in atin g f e ature o f the depo sits was the m ix ed f aun a

o f a stro n g litto ral type (9 , p. 9 3 5 ) .

T h e E o cene age o f the P eb b le P o in t B eds ( i.e ., at W ilk in so n ’s

No. 6 lo c ality) , has been estab lish ed b y the co ntem po raneo us

rec o gnitio n o f the n autilo ids A t u r o i d e a d i s t a n s T e ic h ert sp. an d

N a u t i l u s v i c t o r i a n a T e ic h e rt sp. (1 1 ) and th e pelecypo d L ah illia

( 1 0 ) . I t is no ted th at A turo ide a m ay even be o f U pper C retac eo us

age ( 1 1 ) .

M r. W . J . P arr an d D r. M . F . G laessner have ex am in ed th e

m atrix in whic h the E o cene m o llusc a were fo und, an d also th e

c lay b eds o verlyin g them , f o r f o ram in if era. N o f o ram in if e ra

were fo und in the c lay beds, b ut th e f o ram in if e ral co ntent o f th e

P eb b le P o in t B eds is listed in the ac c o m pan yin g appen dix .

O c currenc e , N a ture , and St ra t ig ra p h ic a l R e la tionsh ip s .

T h e bed f ro m wh ic h the E o cene m o lluscs were co llec ted is

ac c essib le in c lif f sec tio ns at a po int h alf a m ile n o rth -west of P eb b le P o in t, at h eigh ts o f so m e 4 0 to 50 feet ab o ve sea level, in

a f e rrugin o us series c alled the P eb b le P o in t B eds, whic h are ap p ro x im ate ly 50 feet th ic k, and dip in a w e sterly direc tio n . T h e

c o ntained f o ssils so f ar reco gnized are f o ram in if era, A turo idea,

N autilus, L ah illia , C uc ullaea, N uc ulan a, L im o psis, E o trigo n ia, D entalium , N atic a, T urrite lla , a tro cho id gastero po d, a sm all fo rm

o f c o ral, large and m inute fish teeth , c laws o f C allian assa, f ish

verteb rae , o to liths, whaleb o ne f ragm en ts, and o cc asio nal f ra g ­

m ents o f fo ssil w o o d; the sh e lly fo ssils are o f ten m uch b ro ken and

wo rn, an d are em b edded in a m atrix o f h eavy g rit with a f e r­

rugin o us and argillac e o us cem ent. T h e f o ssilif e ro us g rit band

o verlies so m e 30 to 4 0 feet o f sh allo w water, f riab le , san dy iro n ­

sto nes whic h fo rm th e b ase of th e E o cene at th is lo c ality, and

which so f ar h ave pro ved b arren o f determ in ab le fo ssils, altho ugh rare , sh e ll- like f ragm en ts can be detected.

T h e b asal E o cene b eds rest upo n an ero sio n surf ac e o f arko ses

( 6 ) . an d o cc asio nal grits an d m udsto nes o f J u ras s ic age (P I . X .,

figs. 1 an d 2 ) . O ccasio nal grit b ands, n arro w vein s an d th ic ker b ands o f m assive iro nsto ne ( lim o n ite ) , o ccur in the E o cene san dy

iro nsto nes belo w the f o ssilif e ro us g rit b and, wh ile n arro w bands

o f c o piapite-b earin g c lays and th ic ker b ands o f m assive iro nsto ne

o ccur in terstratif ied with the upper laye rs o f the f errugin o us beds.

O verlyin g the P eb b le P o in t B eds o cc urs a deeper w ater sedi­

m en tary fac ies co m po sed o f dark-c o lo ured, carb o naceo us c lays,

whic h in parts co ntain ab un dan t co piapite (b asic iro n sulp h ate ) an d struc tures resem b lin g algal rem ain s. T h e we sterly dip o f the

series b rin gs these c lays do wn to sea level n o rth -west o f P eb b le P o in t, and th e ir th ic kn ess, as determ ined fro m a traverse alo ng

the c o astal sec tio ns in th e gen eral direc tio n of dip, is ap p ro x i­

m ate ly 8 0 0 feet. T h ree b ands o f sandsto ne are in terb edded in

the carb o naceo us c lays, and are in dic ated in th e c o astal sec tio n (f ig. 2 ) . T h e n earest sandsto ne bed to P eb b le P o in t, m arked as

“ h ard f errugin o us sandsto ne ” is p art ly f errugin o us an d po ssesses

in p arts ro unded struc tures wh ic h h ave been pro duced b y weath er­

ing. W h en b ro ken o pen, so m e o f these struc tures are fo und to be sim ilar to “ b o xsto nes ” in c o n tain in g o cc asio nal casts an d

m o ulds o f ec hino ids (S c h iz as te r sp. in det.) and pelec ypo ds, but the fo ssils are o rigin al to the depo sit, an d are no t rem an ie as in true b o xsto nes.

A seco nd sandsto ne bed f urth e r to the n o rth -west, co ntains

num ero us ex am ples o f a sm all fo rm o f T u rrite lla , with co rals,

vo lutes, an d N atic a, wh ile a sho rt distanc e f ro m this bed a th ird

sandsto ne band 4 -5 feet th ic k, co ntains ab un dan t co rals and sh ark ’s

Eocene Deposits South-east, of Princetown, V ictoria. 241

242 George Baker:

teeth, and o c c asio nal spec im ens o f V o luta and D en talium . T h is

bed is m arked in fig. 2 as the “ T ro c h o c yath us-O do n taspis ■ ” b and,

an d the lo c ality co rrespo nds to W ilk in so n ’s N o. 7 lo c ality.

B etween , ab o ve, and b elo w these b ands o f sandsto ne, th e c a r ­

bo naceo us c lays appear, at in tervals in the co astal sec tio ns, but in m an y places th ey are m asked b y recent talus co nes b uilt up by

lan dslides and large f allen b lo cks o f ro ck. I n parts, the c lays are

pale ye llo w and grayish in co lo ur f ro m weath erin g, b ut when wet,

the darker co lo ured po rtio ns are in ten se ly b lack. O ccasio nal

po lyzo al rem ain s o ccur in c lays ab o ve the T ro c h o c yath us-

O do ntaspis bed, wh ile c ro ss sec tio ns o f ec hino id spines appear in

a m icro sco pe sec tio n o f p yrit ic po rtio ns of the c lay f ro m a lo c ality

ab o ut l j m iles n o rth -west o f P eb b le P o int. P o rtio n s o f the c lay beds are distin c tly sh ale- like an d so m ewhat o f a b itum ino us

c h arac ter, esp ec ially ab o ve the T ro c h o c yath us-O do n taspis bed,

wh ere c rystals o f gypsum an d ab un dan t p ale ye llo w, earth y co pia-

p ite are also pro m inent. T h is carb o naceo us sh ale is o verlain b y

35 feet o f un f o ssilif e ro us, f riab le , red an d ye llo w f errugin o us sandsto nes which sho w c h em ic al b an din g an d co ntain o cc asio nal

h ard b ands o f lim o nite. T h ese b eds are fo llo wed b y 2 5 f eet of

d ark - gray c lay with struc tures an d m arkin gs resem b lin g algal rem ain s. T h e o utc ro ps in the c lif f sec tio ns at th is lo c ality, c o rre­

spo nd in po sitio n with W ilk in so n ’s N o . 8 lo c ality, whic h is ab o ut

h alf a m ile so uth -east o f the m o uth o f the G ellib rand R ive r. T h e

b eds h ere dip at 5° in a direc tio n a f ew degrees no rth o f west.

T h ey are o verlain b y san dy c lays an d iro n sto n e, 8 to 10 f eet of b lack c lay, f o llo wed b y f urth er san dy c lays an d iro n sto n e, which

all dip no rth o f west at 4 ° .

T h e O lder T e r t iary beds at the n o rth -west end o f th is traverse ,

cease ab rup tly again st P le isto c en e dune lim esto ne depo sits a q uarter to h alf a m ile so uth -east o f the G ellib rand R iv e r m o uth.

F ro m h ere .to th e G ellib rand R iv e r, the c o astal distric t co nsists o f

R ecent dune san ds (f ig. 1 ) . T wo an d a .h alf to th ree m iles n o rth ­

west o f the G ellib rand R iv e r m o uth, c lays c o n tain in g a typic al

B alco m b ian ( = M io c en e) f aun a, appear in the c o astal sec tio ns, a t a po sitio n c o rrespo n din g with W ilk in so n ’s N o. 9 lo c ality (f ig. 1 ) . T h ese b eds dip w e sterly at 5 ° , b ut the dip values dim in ish

in am o unt in a w e sterly d irec tio n ; th ey are s trat igrap h ic ally sev.eral

h undred feet ab o ve the P eb b le P o in t B eds. ; . .

T h ere is a co n siderab le gap in expo sures o f the T e rt iary ro cks

in the c en tral po rtio n o f the trave rse lin e alo n g th e dip o f the T e r t iary bed's in the P rin c eto wn distric t, b ec ause th e P lio c ene an c esto r of the . G ellib rand R iv e r h ad c arved o ut a v alle y so m e

4 to 5 m iles wide and o ver 3 0 0 feet deep in th e O lder T e rt iary

depo sits. T h is v alle y was sub sequen tly in f illed in suc c essive stages with P le isto c en e dune lim esto ne, th ro ugh whic h the presen t G elli­

b rand R iv e r h as cut' its c o urse. A s a co nsequence, no expo sures

o f T e rt iary sedim ents are presen t f o r a h alf to th ree -q uarters o f

a m ile b etween the E o cene b eds so iith -east o f the G ellib rand RiV'er,

an d the M io cene beds' n o rth -west o f th is rive r m o uth. D if f iculty

o f ac cess to po rtio ns o f the c o astlin e n o rth -west o f the riv e r m o uth

an d th e m askin g o f the T e rt iary ro cks in m o st places b y ex ten sive

talus co nes c o n tain in g large f alle n b lo cks o f P le isto c en e dune

lim esto ne, are also p art ly respo nsib le f o r th e lac k of detailed

in fo rm atio n c o nc ern ing the beds in terven in g b etween P o in t R o n ald

an d the G ellib rand C lays o f M io cene age so uth -east o f G leharflple

S teps (f ig. 1 ) .

T h e traverse alo n g the c o astal c lif f s f ro m P eb b le P o in t to the

m o uth o f the G ellib rand R iv e r, ho wever, has yie lded m o re f avo r­

ab le results, b ec ause the O lder T e rt iary ro cks dipping in a gen eral

we sterly direc tio n , o utcro p f re q ue n tly o ver a distanc e of so m e 2

m iles. T h e relatio n sh ips of the vario us m em b ers o f th is series,

as f ar as can at presen t be asc ertain ed, are diagram m atic ally rep re ­

sented in fig. 2 . E ast o f the are a em b raced b y th e sketch

geo lo gic al sec tio n, the E o cene b eds can be seen in p arts at h eigh ts

o f 50 feet o r m o re in h igh , steep c lif f s, wh ere th ey appear to be

m o re o r less h o rizo n tal; th ey h ave been trac ed o ut b eyo nd P eb b le

P o in t, as f a r east as M o o n ligh t H ead. T h e E o cene also appears

in ro ad c uttin gs alo n g the G reat O c ean-ro ad, on th e n o rthern side

o f the G ellib rand R ive r, n o rth -east o f R ivern o o k H o use.

P £ B 8 uE

Eocene Deposits South-east of Princetown, V ictoria. 243

F i g . 2 .— Geolog ic a l ske tc h se c tio n a lo ng th e c o a s ta l c liffs from th e m outh o f the G e llib ra nd

R ive r to P ebble P o in t . D ip s o f beds a re e x a g g e ra te d ; th e leng th o f th e se c tio n

c o ve rs a d is ta n c e o f 2 -i m ile s , a nd the m ax im um he ig h t o f th e c liffs is about

2 0 0 fe e t . N um bers above the sec tion r e fe r to W ilk in s o n ’s lo c a litie s .

E oc ene -Ju ra ss ic R e la tionsh ip s .

T h e un c o n fo rm ab le jun c tio n b etween the b asal b eds o f the

E o cene an d the ero ded surf ac e o f the J u ras s ic sedim ents is sh arply

defined and re lativ e ly even in c h arac ter in th e c lif f sec tio ns n ear

P eb b le P o in t. T h e surf ac e o f un c o n f o rm ity slo pes do wn to sea-

level f m ile n o rth -west o f P eb b le P o in t, an d beco m es h idden b y

R ec en t b each sands, b ut a J u ras s ic o utc ro p o f lim ited ex ten t

3 1 3 0 / 4 3 .— 7 •

244 George Baker:

ap p ears in th e c o astal sec tio ns b eneath L o wer T e rt iary c lays , a

sh o rt distan c e f urth e r to th e n o rth -west, th us in dic atin g o cc asio nal

un dulatio n s in the J u ras s ic sedim ents f o rm in g the f lo o r o f the

E o cene sea. S o uth -east o f P eb b le P o in t, th e surf ac e o f unco n­

f o rm ity rises to co n siderab le h eigh ts in steep c lif f s, an d c o ntinues

e aste rly f o r 4 m iles to th e G able an d M o o n ligh t H ead, in th e

p arish o f W an ge rrip , wh ere it h as a m o re o r .less h o rizo n tal

dispo sitio n .

T h e E o cene b eds, wh ic h are c o nfo rm ab le with o ne an o th er,

sho w sligh t am o un ts o f tran sgressive o verlap n o rth -west of P eb b le

P o in t. S an dy iro nsto nes, g rit b ands an d n arro w b ands o f m assive

iro nsto ne (lim o n ite ) dippin g w e ste rly at 5° o verstep one ano ther

on to the ero sio n surf ac e in th e J u ra s s ic sedim ents, a surf ac e

which slo pes at 10° in a w e ste rly direc tio n . O n ac co unt o f th is

o verlap, it is reaso n ab le to assum e th at s t ill o lder m em b ers o f the

E o cene series m ay be h idden b elo w sea level west an d n o rth -west

o f the P eb b le P o in t B eds. B o rin g o peratio n s w ill be req uired,

h o wever, to estab lish th is po int.

O n the seaward end o f a wave-c ut p latf o rm , whic h is 140 yards

wide at th e th ird po int n o rth -west o f P eb b le P o in t, m assive b lo cks

o f E o cene iro nsto ne, co m po sed p rin c ip ally o f lim o n ite , rest upo n

the J u ras s ic sedim ents. T h e ir dispo sitio n suggests th at th ey h ave

been lo wered several f eet on to th e J u ras s ic p latf o rm , b y the

rem o val f ro m b elo w them o f th e m o re re adily ero ded E o cene

■ san dy iro nsto nes.

O c casio nal n arro w c rac ks, an inch o r so wide and 6 o r 7 feet

deep in the J u rass ic ro cks, h ave been in f illed with m aterial the'

sam e as th at c o m prisin g the b asal E o cene beds. R o un ded peb bles

o f ree f q uartz are co nspicuo us in the m atrix o c c upyin g these

c rac ks.

Ag e and T h ic kness o f th e T e rt ia ry D eposits .

O f the dippin g L o wer T e rt iary b eds expo sed so uth -east of

P rin c eto wn and ex ten din g beyo nd P eb b le P o in t, o n ly the P eb b le

P o in t B eds o f grits and iro nsto nes can at presen t be assign ed an

E o cene age with an y degree o f c ertain ty. A p p ro x im ate ly 50 feet

o f these depo sits are expo sed ab o ve the surf ac e o f un c o n fo rm ity

with J u rass ic sedim en ts, b ut f o r reaso ns given e arlie r , th is

f o ssilif e ro us, f errugin o us series o f O lder T e rt iary beds m ay h ave

a gre ate r th ic kn ess than is eviden t at the surf ac e .

T h e co nc lusio n th at the .depo sits are o f E o cene age is b ased upon

T e ic h e rt’s (1 1 ) an d S in gle to n ’s (1 0 ) f o ssil determ in atio n s in

,the gro up o f the m o llusc a, an d is suppo rted b y evidenc e f ro m the

f o ram in if e ral co ntent (se e appended lis t ) . T h e th ic kness o f th e

sedim en ts o v erlyin g P eb b le P o in t B eds an d term in atin g again st

dune lim esto ne \ m ile so uth -east o f the m o uth o f the G ellir

b ran d R iv e r h as been c alc ulated grap h ic ally at ab o ut 1 ,000 feet.

T h is value is o b tained f ro m the f ac t th at b eds dippin g at 5° o ut­

c ro p f o r so m e 2 m ile s ; the effects of f o ldin g an d f ault in g have

been n eglec ted f ro m the c alc ulatio n b ecause th ere is no f ield

eviden c e o f such earth m o vem ents in the im m ediate lo c ality.

., L it t le co n c lusive evidenc e is at presen t availab le c o nc erning

th e prec ise age o f th e depo sits o verlyin g the P eb b le P o in t B eds

n o rth -west o f P eb b le P o in t I n view o f D unc an’s desc riptio n o f

th e c o ral with a th in c o rallum . determ in ed as C y c l o s e r i s t e n u i s ,

b ut no w c lassed as F u n g i a ( C y c l o s e r i s ) t e n u i s ( 7 , p. 3 6 2 ) , and

h is rec o rd o f ab un dan t th in fo rm s o f th e C yc lo serides gro up in

the E o cene sedim ents of S o uth ern F ran c e , it is pro b ab le th at the

T e rt iary depo sits b etween the P eb b le P o in t B eds and the P le isto ­

cene dune lim esto ne m ay also be o f E o cene age. O ther fo ssil

f o rm s like O do ntaspis, I surus, T ro c h o c yath us, T u rrite lla , an d

S c h izaster, c o llec ted f ro m the vario us m em b ers o f th is series, are

types , whic h elsewh ere h ave a tim e ran ge whic h inc ludes the

E o c ene perio d, alth o ugh th ey are not n ec essarily c h arac teristic o f

th at age, T r o c h o c y a t h u s v i c t o r i a e .D uncan sp., f o r in stan c e, o ccur-

in g 1 R ec en t in P o rt J ac kso n an d P o rt S teph en s, N ew S o uth W ales

(7 , p. 4 3 6 ) , as well as in the O lder T e rt iary depo sits ab o ve the

E o cene b eds o f P eb b le P o int.

T h e f ix atio n o f the upper lim it o f these E o cene b eds m ust,

th e re f o re , rem ain in ab eyan c e un til f urth e r evidenc e is forth^

c o m ing f ro m in vestigatio n s o f the fo ssil co ntent of the beds ab o ve

the P eb b le P o in t E o cene beds. F ro m th e f ield evidenc e, the

auth o r is in c lin ed to the belief , th at all o f the b eds so uth -east o f

the m o uth o f th e G ellib rand R iv e r are o f E o cene age. T h is

in c lin atio n is b ased upo n the lith o lo gic al an d m in eralo gic al s im i­

larit ie s o f tho se carb o naceo us c lays wh ic h are in terc alated with

the upper laye rs o f the f e rrugin o us P eb b le P o in t E o cene b eds,

an d tho se whic h o ccur at in tervals up to 2 m iles n o rth -west o f

P eb b le P o in t. T h ere are also m in eralo gic al s im ilarit ie s (see

T ab le 1 ) b etween th e E o cene g rit b ands an d the th ree sandsto ne

b ands c o n tain in g S c h izaster, T u rrite lla , an d T ro c h o c yath us-

O do ntaspis, respec tive ly (f ig. 2 ) . I n additio n to th is, th ere seem s

to be no do ubt in the f ield th at all o f the beds so uth -east o f P rin c e ­

to wn are co n fo rm ab le with one ano ther. T h e T u rrite lla b and also

c o ntains a few gastero po ds co m parab le with ones in the P eb b le P o in t B eds.

Eocene Deposits South-east of Princetown, V ictoria. 245

246 George Baker:

T h e changes in th e lith o lo gic al c h arac ter o f th e sedim ents f ro m

so uth -east to n o rth -west, in dic ate a deepen in g o f th e L o wer

T e r t ia ry sea in a gen eral east to west direc tio n , the lit to ral f ac ies

o f undo ub ted E o cene age at P eb b le P o in t, g iv in g w ay in th e n o rth ­

west to c lays c o n tain in g o c c asio nal in terb edded sandsto nes. T h ree

-miles n o rth -west o f P o in t R o n ald, c lays o f M io c ene age, with a

" typical B alc o m b ian f aun al assem b lage an d with sim ilar dips to th e

E o c ene depo sits so m e 6 m iles to th e so uth -east, pass upwards, with

•dim inishing dips, into M io c en e lim esto nes, c alc areo us c lays an d

m arls . T h ese are m o re o r less h o rizo n tal in th e v ic in ity o f

G lenam ple S teps (se e m ap, f ig. 1 ) an d ex ten d w e ste rly f o r m an y

m ile s th ro ugh P o rt C am pb ell, P eterb o ro ugh , an d W arrn am b o o l.

P o st-M io c en e c lays an d R ec en t san d dunes o verlie the M io cene

lim esto n es, wh ile P le isto c en e dune lim esto nes rest un c o n fo rm ab ly

upo n the ero ded surf ac es o f m an y 'm embers of the L o w er T e rt iary

s trata.

L ith o lo g y and M ine ra lo g y.

T h e m in eral spec ies represen ted in th e vario us lith o lo gic al types

o f the L o w er T e rt iary series so uth -east o f P rin c e to wn , are listed

in T ab le 1. T ho se f ro m th e J u ras s ic sedim ents o f the im m ediate

neighb o urho o d h ave b een added f o r purpo ses o f co m pariso n.

J u r a s s i c .

T h e J u ras s ic arko se n ear P eb b le P o in t is c alc areo us (4 2 p e r

c en t, ac id so lub le ), an d co ntains a sm all am o un t (6 per c en t.) o f

c lay co nstituents. T h e san dy f rac tio n o f th e arko se is co m po sed

p rin c ip ally of an gular q uartz , with so m e o rth o c lase an d o ligo c lase,

wh ile th ere are also n um ero us sub -an gular to ro unded ro ck f ra g ­

m en ts o f m icro sco pic size, determ in ed as an desite , m usco vite

sc h ist, c h lo rite sc hist, sandsto ne, q uartz ite , m udsto ne, an d h o rn fe ls

( 6 ) ; these ro ck f ragm en ts and the q uartz grain s are all o f rem ark ­

ab ly even grade size. P lates o f f resh b io tite , m usc o vite , green

an d reddish -b ro wn ho rnb lende, c h lo rite , c o lo urless, pink and

b ro wn garn et, epido te, sphene, leuc o x en e, h em atite , trem o lite ,

zo isite , stauro lite , an d apatite , are also represen ted in additio n to

the m in erals listed in T ab le 1. T h in sec tio ns o f the arko se reveal

ab un dan t c alc ite ac tin g as the c em enting m edium an d f o rm in g rim s

to m o st o f the sm all ro ck f ragm en ts an d m in eral grain s. I n th is

f e ature and in several o ther respec ts, the ro c k resem b les som e

ex am p les o f the J u ras s ic arko se f ro m the G ippsland b o res, e .g.,

o ne f ro m a depth o f 1 ,163 feet in b o re N o. 4 , at B o o larfai:

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L o w e r ! T e r t i a r y .

T h e isandy iro nsto ne at th e b ase o f th e E o cene series co ntains

o c c asio nal f ragm en ts o f an gular q uartz and f e lsp ar, an d also reef

q uartz , J u ras s ic peb b les, an d rare q uartz ite pebbles. I n additio n ,

rare ro un ded o o litic grain s o f the h ydrated lim e pho sphate m in eral

co llo phane, pellets o f glauc o n ite an d grain s of b lac k iro n o x ide,

are set; in a lim o n itic c laye y b ase wh ic h fo rm s the p rin c ip al c o n ­

stituen t o f the ro ck.

B o th th e f o ssilif e ro us an d the n o n -fo ssilif ero us grit b ands in te r­

b edded with the san dy iro nsto ne, co n tain n um ero us large and ro unded, tran sluc en t q uartz grain s , o c c asio nal gypsum c rystals

an d qulartzite f ragm en ts. T h ese c o n stituen ts are set in a c layey b ase wh ic h varie s in co m po sitio n f ro m plac e to place. I n parts ,

th e b ase is f errugin o us an d pho sphatic , and co ntains rare c rystals o f zirc o n , m ic a an d to urm alin e, p ellets o f co llo phane, and areas

o f glauc o n ite so m etim es asso c iated with c alc ite. I n o ther parts,

th e m atrix is co m po sed p rin c ip ally o f c alc ite an d lim o nite, wh ile

elsewh ere, green and green ish -b ro wn glauc o n itic m ud is th e m o st

co nspicuo us co n stituen t in the b ase o f th e ro ck. S m alle r q uartz

grain s in the g r it b ands are sub -an gular to ro unded an d c lear, the

large r grain s are f re q ue n tly strain ed an d gran ulated , an d co ntain

n um ero us strin gs o f o paque, dust- like in c lusio n s. S h ell f ragm en ts

are co m m o n in c e rtain o f the g r it b ands, an d h ave in p art been

replac ed b y lim o n ite an d p yrite .

T h e carb o naceo us c lays o v erlyin g the b asal f e rrugin o us series

co ntain p yrite in plac es. A sec tio n o f p yrit ic c lay, f ro m 1^ m iles

so uth -east o f P o in t R o n ald, revealed th at q uartz grain s present

we re rim m ed with c alc ite as in the c alc areo us J u ras s ic arko se.

T h e p yrite , wh ic h is f in ely gran u lar, so m etim es fo rm s rim s to ,

o r en tire ly replac es th e o o litic co llo phane grain s presen t, b ut p rin ­

c ip ally :replac es the argillac eo us m aterial f o rm in g th e b ulk o f th e

ro ck. T h e sec tio n o f p yrit ic c lay also revealed rare c ro ss sec tio ns

o f ec hino id spines an d o cc asio nal shell f ragm en ts. C arb o nac eo us

sh ale f ro m % m ile so uth -east o f P o in t R o n ald h as c ertain c h arac ­

te ris tic s ak in to so m e o il shales. I t h as a san dy f rac tio n o f 7 -5 per

cent, an d co ntains trac es o f c alc areo us m atter. T h e san dy f rac tio n

is co m po sed m ain ly o f c o lo urless, tran sluc en t, an d m ilk y grain s o f

q uartz . T h ere are also f lakes o f m ic a up to 2 m m . ac ro ss, an d

rare gr'ains o f h eavy m in erals (c o lum n 2 , T ab le 1 ) , wh ile gypsum

o cc urs |as b laded c rystals up to 3 m m . in len gth , an d co piapite

is ab un dan tly develo ped alo n g plan es o f f iss ility an d as irre gu lar

c lo ts. T h e c lif f s h ere give off a sulph uro us o do ur. A th in sec tio n

o f th is: sh ale in dic ated the presen c e o f p lan t- like f ragm en ts.

P o rtio n s o f th e carb o nac eo us sh ale we re tested f o r h ydro c arb o n

co m po unds. A f te r h eatin g ab o ut I S gram s: o f po wdered m aterial

to a dull red h eat in a h ard glass test tub e, ab un dan t c arb o n was

le f t b ehind in th e residue. V o latile c o n stituen ts f ro m dry d is t illa­

tio n co nsisted o f water f ro m wh ic h h alite cubes c rystallized on

c o o ling, a sm all am o un t o f sulph ur, an d a f ew dro ps o f c o lo urless

liq uid wh ic h h ad an aro m atic sm ell an d whic h when ex am in ed

m ic ro sc o pic ally, were seen to co ntain pale ye llo wish -green glo b ules

o f a liq uid wh ic h persisted f o r several weeks. T h e h alite cub es,

wh ic h we re ac co m panied b y skeleto n c rystals o f th e sam e m aterial,

were pro b ab ly derived f ro m salt sp ray driven again st the c lif f fac e

f ro m th e sea. T en to f if teen gram s o f the sh ale were po wdered

an d treated with ab so lute alco ho l, an d the argillac e o us m atter

f iltered off. T h e f iltrate was allo wed to evapo rate slo wly, an d at

th e end o f th is pro cess, b ro wn ish -yello w h ydro c arb o n residues

h avin g w ax - lik e pro perties, rem ain ed as a th in f ilm on th e bo tto m

o f the c o n tain in g vessel. A po sitive aceto ne test f o r h ydro ­

carb o ns was o b tained by sh akin g up ab o ut 10 gram s o f the

po wdered sh ale with ac eto ne and f ilterin g. T h e additio n o f w ater

to th e c lear f iltrate , resulted in a m ilky c o lo uratio n due to the

fo rm atio n o f an em ulsio n. T h is m ilkin ess did no t develo p in a

c o n tro l test c arried o ut b y addin g w ater to p ure aceto ne. T welve

gram s o f th e po wdered sh ale were sub jec ted to h o urs’ tre at­

m ent with petro leum eth er in a S o x h le t ex trac tio n ap p aratus.

T h e residue o b tained af te r evapo ratin g the petro leum eth er ex trac t

c o n tain ed ab un dan t sm all c rystals of sulph ur, a wh itish , w ax - lik e

sub stan c e an d a pale ye llo wish liq uid with an aro m atic o do ur.

O win g to th e sm all am o unts of the residues o b tained f ro m each

o f the ab o ve tests, it has no t been po ssib le so f ar to arr iv e at an y

def in ite co nc lusio n re gardin g the ex ac t c h arac ter o f the h ydro ­

c arb o n co m po unds presen t in the carb o naceo us shale.

O f the in terb edded sandsto nes in th e c lay series, the bed with

s truc tures resem b lin g b o xsto nes c o n sists p rin c ip ally o f q uartz ,

with m usc o vite an d so m e f e lsp ar set in a lim o n itic cem ent co n­

tain in g c alc ium carb o nate an d glauc o n itic m aterial (c o lum n 6,

T ab le 1, f o r rare r m in eral sp ec ie s). T h e c alc ium carb o nate fo rm s

rim s aro un d so m e o f th e sedim en tary grain s , an d h as also pene­

trated c leavage plan es in c ertain o f th e m ica plates. T h e san d­

sto ne b and with T u rrite lla co ntains so m e alte re d f e lsp ar and a

c arb o n ate ■ cem ent in whic h an gular to sub -an gular q uartz grain s

are set. T h e sandsto ne with T ro c h o c yath us an d O do ntaspis has

a f e rrugin o us to c alc areo us cem ent, an d c o ntains a sm all pro po r­

tio n o f o ligo c lase an d m ica. N o dular areas of p yrite up to 4 mm .

ac ro ss are. n um ero us in th is sandsto ne band,' an d f req uen tly

e n t ire ly replac e th e argillac e o us m atrix presen t in p arts o f the

ro ck. S o m e o f the an gular to sub -an gular q uartz grain s co n tain

lo ng, slen der n eedles an d m inute prism s o f ap atite . R ar6

Eocene Deposits South-east pf Princetown, V ictoria. 249*

2 5 0 George Baker:

glauc o n ite an d o o litic pellets o f b ro wn co lo ured m aterial, pro b ab ly

c o llo phane represen tin g fish pellets, & c., are also presen t in th is sandsto ne.

T h e f errugin o us sandsto ne o verlyin g the c o piapite-b earin g,

carb o naceo us sh ale ab o ut ^ m ile so uth -east o f P o in t R o n ald, is

f riab le an d in p arts m icaceo us, with an gular to sub -an gular q uartz

grain s. Z irco ns o cc ur bo th as c lear, waterwo rn c rystals and as

exam ples with well preserved c rystal f ac es like tho se in the

J u ras s ic sedim ents. T h e o ther m in erals presen t are listed in co lum n 1, T ab le 1.

T h e m in erals presen t in th e E o cene sedim en ts so uth -east o f

P rin c eto wn h ave several c h arac teristic s in co m m o n with the

m in eral assem b lage o f the J u ras s ic ro cks upo n whic h th ey rest.

T h is is to be expec ted, as th e b asal E o cene beds are o f te rrigen o us

o rigin , th e ir c o n stituen ts b ein g derived f ro m a te rrain co m po sed

o f J u ras s ic arko se , grits , an d m udsto ne. T h e p yrite in the

argillac e o us m em b ers o f th e L o wer T e rt iary series was pro b ab ly

f o rm ed b y th e ac tio n o f H 2S evo lved f ro m dec o m po sing o rgan ic

m aterial, with the aid ,o f b ac teria, on f erro us carb o nate. W e ath e r­

in g o f the p yrit ic m atter h as b ro ugh t ab o ut c o nversio n to b asic

f e rr ic sulphate, re sultin g in th e ab un dan t develo pm ent o f the

m in eral co piapite in p arts o f th e depo sits. H ydro c arb o n co m ­

po unds presen t in the c lays o rigin ate f ro m plan t m aterial,

represen ted b y th e d ark carb o naceo us m ark in gs , resem b lin g algal

rem ain s. T h e reef q uartz peb b les in th e P eb b le P o in t B eds were

derived f ro m q uartz vein s wh ic h trav e rse the J u ras s ic sedim en ts

in p arts o f the O tways.

Sum m a ry and C onc lusions.

A w e ste rly dippin g series o f L o wer T e r t iary sedim ents co m ­

po sed o f a b asal f errugin o us ph ase (c alle d the P eb b le P o in t B eds)

o verlain b y a c lay ph ase with in terb edded san dsto n es, in c o astal

sec tio ns so uth -east o f th e to wnship o f P rin c eto wn , on th e so uth

c o ast o f W estern V ic to ria, h ave been assign ed an E o cene age on

th e ir fo ssil co ntent. T h ey rest un c o n f o rm ab ly upo n an ero ded,

so m ewhat un dulatin g surf ac e in J u ras s ic sedim en ts, an d sho w

sligh t tran sgressive o verlap. B alc o m b ian (M io c e n e ) b eds in c lif f

sec tio ns so m e 5 o r 6 m iles n o rth -west o f P eb b le P o in t, are

separated f ro m the o lder T e r t iary sedim ents b y a stretc h o f

P le isto c en e dune lim esto ne whic h fo rm s steep, rugged c lif f s, at

the b ase o f wh ic h o c c asio nal o utc ro ps o f T e rt iary ro cks can be

seen am o ngst large talus co nes in tho se p arts o f the co ast to whic h

ac c ess c an be gain ed. A co n siderab le gap in c ertain p arts o f th e

T ^ f t iary ro cks b etween P eb b le P o in t an d G lenam ple S teps, h as

been c reated b y-th e ero ded v a lle y o f the presen t G ellib ran d R iver

and its P lio c en e an c esto r, so th at no def in ite co nc lusio ns c an be

m ade at presen t c o nc ern ing the ex ac t relatio n sh ip b etween the

E o cene an d the M io c ene depo sits. T h e E o cene depo sits h ave no

o ther eq uivalen ts, as f ar as can be asc ertain ed, alo n g these p arts o f the V ic to rian c o astlin e, b eing kno wn so f ar o n ly f ro m the

P eb b le P o in t distric t.

T ran sgressive deepening o f th e L o wer T e rt iary sea f ro m east

to west is sho wn b y the passage f ro m b asal E o cene grits an d

san dy iro nsto nes, th ro ugh c lays an d sh ales with in terb edded san d­

sto nes, into M io cene lim esto nes an d c alc areo us, f o ssilif e ro us c lays.

E videnc e o f P o st-M io c en e earth m o vem ents is pro vided b y the

elevatio n o f th e are a o f E o cene an d M io c ene sedim en tatio n to

its present po sitio n ab o ve sea level, b ut th ere was ap p are n tly no

sign if ic an t disturb an c e o f the beds f ro m th e ir o rigin al dispo sitio n

on depo sitio n , the reco rded dip values pro b ab ly b eing in it ial dips

c o ntro lled b y th e slo pe o f the ero sio n surf ac e o f th e J u ras s ic

c o astlin e, rath er th an dips resultin g f ro m tilt in g on elevatio n .

I n stead o f a co ntinuo us perio d o f ero sio n leadin g to pen eplan a-

tio n th ro ugh o ut the C retaceo us an d E o cene an d into O ligo c ene

tim es in V ic to ria, as o rigin ally appeared to be th e case, it no w

tran sp ire s , with th e determ in atio n o f the E o cene age o f th e O lder

T e rt iary depo sits so uth -east of P rin c eto wn , th at in po rtio n o f

so uth -western V ic to ria at least, do wn -warpin g h ad set in to wards

th e c lo se o f C retaceo us tim es. E ro sio n th ro ugh o ut the C retaceo us

perio d h ad led to the develo pm ent o f a so m ewhat peneplaned area

in th e P rin c eto wn distric t. I n c reased am o un ts o f do wn -warpin g

led to th e depo sitio n o f deeper w ater sedim ents in the west un til,

at the c lo se o f M io cene tim es, th ere was a re versal of m o vem ent,

an d th e E o c ene-M io c ene ro c ks were elevated to fo rm a lan d m ass.

T h e so uth ern f rin ge o f th is elevated th eatre of O lder to M iddle

T e rt iary sedim en tatio n has been sub jec ted to m arin e attac k since

M io cene tim es.

Eocene Deposits South-east of Princetown, V ictoria. 251

Ac knowledgm en ts .

T h e auth o r wish es to ex p ress h is apprec iatio n o f the wo rk o f

D r. C. T e ic h e rt an d D r. F . A . S in gleto n , who se fo ssil determ in a­

tio n s h ave pro ved the presen c e o f E o cene depo sits in V ic to ria,

a t the lo c ality desc rib ed in th e te x t . T h an ks are also due to

A sso c iate P ro f esso r E . S . H ills an d D r. M . F . G laessn er f o r

valuab le help an d advic e, to M r. W . J . P arr f o r h is ex am in atio n s

o f th e f o ram in if e ral co ntent o f th e sedim en ts f ro m so uth -east o i

P rin c eto wn , an d to M r. J . S . M an n f o r pho to graphic preparatio n s.

252 . George Baker:

Append ix .

T h e F o r a m i n i f e r a o f t h e E o c e n e B e d s a t P e b b l e P o i n t , P r i n c e t o w n .

B y M . F . G l a e s s n e r , P h .D ., a n d W . J . P a r r .

T h e presenc e o f f o ram in if e ra in the E o cene b eds o f the P eb b le P o in t are a was f irst rec o gn ized b y G . B ak e r, M .S c ., who sub seq uen tly asked us to ex am in e so me o f the m atrix adh e rin g to th e la r g e r f o ssils to o b tain , if possib le, evidence f ro m the m ic ro sc o pic f o ssils as to th e age o f the depo sit. A s no depo sits no w ac c epted as o f undo ub ted E o cene age h ave h ith erto been reco rded f ro m S o uth -E astern A u s tralia , we were glad to co m ply with th is request. I n additio n to the m ate rial with wh ic h M r. B ak e r has supplied us, we h ave ex am in ed so m e b etter p reserved m ate rial c o llec ted b y one o f us ( W .J .P .) f ro m the sam e beds in O cto ber, 1915.

F errugin o us gr its , suc h as o c c ur at P eb b le P o in t, are as a rule, un favo urab le to the o c c urren c e an d rec o very o f f o ram in if e ra in an y num b ers, and it is ac c o rdin gly no t surp risin g th at in the presen t c ase the m ic ro f o ssils are rare and o f sm all size. A f te r a c o nsiderab le am o unt o f searc h in g, we have fo und ab o ut 28 spec ies o f f o ram in if e ra and two o f o strac o da. F ro m the ex am in atio n o f the m aterial, it is, h o wever, apparen t that m uch b etter p reserved specim ens co uld be o b tained b y c are f ul c o llec tin g o f sam ples f ro m the le ss f e rrugin o us po rtio ns o f the depo sit.

In the m eantim e, the f o llo w in g pro visio n al list o f spec ies is plac ed on re c o rd :—

D e n t a l i n a sp.

N o d o s a r i a sp.

V a gi n u l i n a sp. af f . s u b p l u m o i d e s P arr .

M a r gi n u l i n a af f . c o s t a t a ( B a t s c h ) .

M a r gi n u l i n a af f . g l a b r a d ’O rb ign y.

L e n t i cu l i n a spp.

P l a n u l a r i a sp.

L a g e n a h e x a g o n a ( W ill. ) .

L a g e n a c a t e n u l a t a ( W ill . ) .

L a g e n a sp.

G l o b u l i n a g i b b a d ’O rb ign y.

G u t tu l i n a p r o b l e m a ( d ’O rb ign y).

G u t tu l i n a l a c t e a ( W a lk e r an d J ac o b ) .

G u t tu l i n a sp. (ad h e re n t ) .

A n g u l o g e r i n a af f . e l o n ga t a ( H a lk ya r d ) .

E p o n i d e s o b t u s u s (B urro w s & H o llan d ) var. w e s t r a l i e n s i s P arr .

G y r o i d i n a af f . o c t o c a m e r a t a C ushm an & H anna.

P u l v i n u l i n e l l a sp. nov.

B a g g a t e l l a sp. nov.

C e r a t o b u l i m i n a spp. nov.

A n o m a l i n a sp. nov.

A n o m a l i n a c f . g l a b r a t a C ushm an.

C i b i c i d e s c f . l o b a t u l u s (W a lk e r and J ac o b ) .

C i b i c i d e s spp.

G l o b i ge r i n a sp.

E c h in o id spines, b ryo zo an f ragm e n ts, sm all m o llusc a, o strac o ds and fish teeth o c c ur also in the wash in gs.

Eocene Deposits South-east of Princetown, V ictoria. 253-

A ll f o ram in if e ra are rare exc ept A n o m a l i n a , sp.. nov. and C i b i c i d e s sp.,■ which were fo und in c o nsiderab le num b ers.

F ro m th is lis t , we have drawn the f o llo w in g c o n c lusio n s:—

1. T h e assem b lage is un like an y o th er h ith erto rec o rded o r kno wn to us fro m A u s tra lia . T h e m o st c h arac te ris t ic spec ies o f th e depo sit appear to be new. A num b er o f o ther species h ave a lo ng ran ge in1 tim e.

2. T h ere is no disagreem en t b etween the co m po sitio n o f th e f aun a and the determ in atio n o f the E o cene age o f the b eds at P eb b le P o int as b ased on distin c tive species o f m o llusc a.

3. O ur presen t kno wledge o f the f o ram in if e ral assem b lage o f the f e rrugin o us gr its f ro m P eb b le P o in t is insuff ic ient f o r an independent

determ in atio n o f th e ir age . A t le as t f o ur o ut o f a to tal o f ab o ut 28 spec ies appear to be c lo se ly re lated to spec ies not kno wn f ro m T e r t ia ry depo sits yo un ger than E o cene. O ne o f these spec ies b elo ngs to the genus B a g g a t e l l a wh ic h was desc rib ed rec en tly b y H . V . H o we f ro m th e M iddle E o cene o f T e x as , U .S .A . (see L o uisian a G eol. S urvey, B ull. 14, p. 7 9 ) . T h e num b er o f specim ens at presen t av ailab le do es no t enab le us to reac h a m o re def inite co nclusio n.

4. T h e co m po sitio n o f the faun a in dic ates depo sitio n in sh allo w and rath e r co o l w ate r. T h is opinio n is b ased on sim ilaritie s with f o ssil f o ram in if e ral assem b lages fro m sedim ents kno wn to h ave been fo rm ed under such co nditio ns.

R efe renc es .

1 . C h a p m a n , F .— F o ssil F ish R em ain s f ro m the T e rt iarie s o f A ustralia .P r o c . R o y . S o c . V i c. , x v ii. ( i ) , n .s., pp. 267-296, 1904.

2 . --------------- , So m e C aino zo ic F ish R em ain s, with a R evisio n o f theG roup. I b i d . , x x x v i. ( 2 ) , n.s., pp. 107-162, 1924.

3. D e n n a n t , J .— D esc riptio ns o f N ew S pec ies o f C o rals f ro m theA ustralian T e rt iarie s . T r a n s , a n d P r o c . R o y . S o c . S t h . A u s t . , x x v iii. , pp. 52-76, 1904.

A . D e n n a n t , J . , and K i t s o n , A . E .— C atalo gue o f th e D escrib ed S pec ies o f F o ssils (E x c ep t B ryo zo a and F o ram in if e ra) in th e C aino zo ic F aun a o f V ic to ria, So uth A ustralia , and T as m an ia) . R e c . G eo l . S u r v . V ic. , V o l. I ., P a r t 2 , pp. 89-147, 1903.

3 . D u n c a n , P . M .— O n th e F o ssil C o rals (M ad re p o raria) o f the A ustralian T e r t ia ry D epo sits. Q u a r t . J o u r n , G e o l . S o c . , x x v i., pp. 284-318, 1870.

•6 . E d w a r d s , A . B . , and B a k e r , G .— J u rass ic A rko se in S o uth ern V ic to ria. P r o c . R o y . S o c . V ic. , lv. ( 2 ) , n .s., 1943.

7 . F e l i x , J .— F o ssilium C atalo gus. A n t h o z o a M i o c a e n i c a ( 1 ) , 35, 1927.

& M u r r a y , R . A . F .— R epo rt on the G eo lo gy o f P o rtio n o f th e C ape O tw ay D istric t. G eo l . S u r v . V i c. P r o g r e s s R e p o r t , V o l. I V ., pp. 127- 133, 1877.

'8 . P r i t c h a r d , G. B .— T he C h arac ter and S equenc e o f the V ic to rian T e rt iarie s . P r o c . P a n . S c i . C o n g r e s s ( A u s t r a l i a ) , V o l. 1, pp. 934 -939, 1923.

10. S i n g l e t o n , F . A .— A n E ocene M o llusc an F aun a f ro m V ic tp ria. T h isvo lum e, pp. 268-281.

11. T e i c h e r t , C.— E o cene N autilo ids f ro m V ic to ria. T h is vo lum e, pp.

257-265.

12. W i l k i n s o n , C. S .— R epo rt on the C ape O tway C o untry. G eo l . S u r v .

V ic. R ep o rt fo r 1863-1864, pp. 21-28, 1865.

254 George Baker:

E x p la n a tio n o f P la te .

P l a t e X .

F i g . 3 .— L owe r p o rt io n o f the c liffs a t the sec ond po in t n o rth -we s t o f P ebble P o in t,.s howing J u ra s s ic beds on the w a ve -c u t p la t fo rm and in the base o f th e c liffs . O ve rly in g them a re w e s te rly d ipp ing E oc ene beds.

F i g . 2 .— C lose -up o f th e u n c o n fo rm ity b e tween E oc ene a nd J u ra s s ic sed im en ts a t th e se c ond po in t n o rth -we s t o f P ebble P o in t , sh ow ing th e e ven c h a ra c te r o f the^ o ld e ro s io n s u rfa c e a t th is lo c a lity.

( N o t e .— T he do tted l in e in ea c h pho tog raph m a rks th e s u rfa c e o f u n c o n fo rm ity b e tween E oc ene a nd J u ra s s ic ro c ks .)

P r o c . R o y . S o c . , V i c t o r i a , 55 ( 2 ) , 1 9 4 3 . P l a t e X .

[Paje 255.1

3 1 3 0 / 4 3 .