The Cainozoic Geology of Flinders Island, Bass Strait'

Home , Bankivia, Barren Island (Tasmania), East Moncoeur Island, Flinders Island, Furneaux Group, Table Cape

PAPERS AND PIWCEIWTNGS OF ~'HB ROY,,'\.L SOCfETY OF T(\SM.ANIA, V01.·UMEl 105

[Manllscript received 20th October, 1970. THE CAINOZOIC GEOLOGY OF FLINDERS ISLAND, BASS STRAIT'

F. L SllTHERLAND (Tasmanian Museum) Hobart and

R. C. KERSHAW (Hon. Malacologist, Queen Victoria Museum) Launceston with Appendix, 2 figures, 6 tables and 2 plates

ABSTRACT R. C. Kershaw visited the Island for 7 days in August 1957, when he collected from The Dutchman quarry and Cainozoic sediments and volcanic rocks superficially Nelson Lagoon drain and made geomorphological overlie the mountainous Palaeozoic basement of Flinders observations, particularly on the dune systems. F. 1,. island and mainly form the coastal plains. Sutherland visited the Island for 3 days in April 1964, Marine deposits include Middle Pliocene to Recent 5 days in April 1965 and 5 days in March 1970, when near-shore and littoral coquinoid beds, and some be sampled volcanic rocks, collected fossil material Quaternary beds appear related to old marine stands (from Holloways quarry, drains and waterholes on the at about 15-18 m., 4.5-6 m. and 0.6-1.5 m. above Furneaux and Wingaroo Estates, and sites around MHWS. Quaternary dune deposits afe predominantly Loccota and Lugbrata), visited the Ranga cave, and calcareous on the west coast and predominantly siliceous made other general observations. The authors also on t.he east coast, and show varying degrees of con examined material previously collected from Flinders solidation and soil development generally related to Island and held in the Queen Victoria and Tasmanian age. A Recent beach ridge and coastal barrier system Museums. Specimens collected by the authors are held is developed and lagoonal deposits include Pleistocene in the Queen Victoria Museum, National Museum of limestone and Recent peat. Non-marine gravel and grit. Victoria and Tasmanian Museum, and thin sections of deposits (including st.anniferous and sub-basaltic deposits) volcanic rocks are catalogued in the Tasmanian Museum. were sometimes reworked by later marine incursions. Specimen numbers refer to the Queen Victoria Museum Scattered volcanic rocks include tuffs, alkali olivine collections, unless otherwise Slated. basalts and olivine-nephelinites, erupted from several This paper deals with the Cainozoic geology of centres roughly aligned along a north·westerly trend. Flinders Island and some of the intcrp relations are based The volcanism was largely Tertiary in age and some on geomorphological data to be presented more fully lavas are lateritised. elsewhere (Kershaw and Sutherland, in press). The Cainozoic history was initiated by fmllting, tilting and uplifting of the Flinders Island block by early GENERAL Tertiary time, with subsequent volcanism. During the Cainozoic, alternations of predominantly terrestrial or Flinders Island (lat. 40'S, long. .I 48'.E, 65 Km. long, marine erosion and deposition on Flinders Island were 40 Km. wide and J ,333 sq. Km. in area) is the largest related to fluctuating sea-levels, which influenced some island in the FurneallX Group, stretching across Bass faunal movements. Strait on the Bassian Rise connecting Victoria and INTRODlJCTION Tasmania (Jennings, 195(8). This paper is based on observations made during visits Thc Island is a mountainOllS basement ridge flanked to Flinders Island by the authors, supplemented by a by coastal plains. The western plain is mostly narrow, study of aerial photographs, unpublished maps and but carries important dune systcms around Marshall reports, museum coHections, and correspondence with Bay and PaJana. The eastern plain is wider and more a number of other workers. In particular, E. D. Gill extensive, with a gentle slope marked by numerous and T. A. Darragh (National Museum of Victoria) dunes and lagoons and several residual basement hills. assisted with radio-carbon and molluscan determinations The steep mountain slopes enSllre rapid run off and and other matters, D. J. Taylor and A. C. Collins deep grit beds on the Hanks afe evidence of the erosive (Melbourne) identified foraminiferal fannas, and a.M.. forces. However the dune sy,tems have dammed the Dimmock (C.S.LR.O.) supplied data and aerial photo drainage to form extensive lagoons whose soils are an graphs related to his soil mapping; other workers are important agricultural asset. The dunes are generally mentioned ill the text and acknowledgment section. stabilised and extensive modern blowouts are very

151 152 THE CAINOZOIC GEOLOGY OF rUNDERS iSLAND, Bl,SS STRAIT

_~E~I::_NJ2 S i l uri Q n (1) HflTi'11NNI'1 6rns C":SCR.r.E&.'lOILCOVEIi;lG:.L~l SM Devonion (1) (}RRNIHS,HC.(+SIJPI<1- !'>ASIC DYKES L_:r--':-:J --Uncoh.fo"tmcl.'J ---

Te1'b,Q.. T 'y CAMERON INLET f"ORMATION ~-:-"':-~_-l Tc TIN-St:ARINC" I

[fIST RIVfR (09~INR RND j- CDIUULRT[S L0CCOTR rzRll ~,,:':~]

N~U! ~A;1[) [-::~--=---=:! 1"'1 LUGHRRTR SfH1D ;::::=~J 'PL~ Lf.1GOONRL LIME _---:-r 'h,_ Recent pcrRI~I'1CnoN BRY o;"lQWINR c_-~-=-~ Fl.,. fI,_ LACKF,f;r-

S"""''''r'' ~ f\,"~_"'~, c~ ... ~. IV- p.~

Fig. L~~-,Gcllcralised geology, Flinders l~\land. Modified from Di01mock (]957). based on unpublished Tasmo:Jian Mines Department mapping hy Blake (1947), Keid (1949), Everard (1950), and D. J. Jennings\ field mapping by T. A. Darragh, D. M-, Shanks and 1-1. E .. Wilkinson (National }\1useum of Victoria party, 1969), and mapping by F, L. Sutherland and R. C, Kt'rshaw (1957·1970). F. L, SUIJ·H~RLANn l'd"-!D R (. KERSHf\V'r' 155 ocalised. Soils of the Island :md biotite trnuscovite) granites and adanlell- mel described by Dimmock smaHer areas of biotite mllS- mel limestone resOlm:es are by and adanleUites n lin1i1ed area of lughes, 1957). and biotite gr;)l1odiorites. granite type" and the outcrop and The geology of the Island consists of a Palaeozoic of the sedimentary ,equence together l<1Semellt overlain with :1 superficial veneer of Cainozoic lb internal s,tructllre. suggests an essentially NNE 'ocks (Figure 1). The basement consists of stcoep!y folded !nartzites and argiliiles, intruded granite, a;,sociaicd treHchllg regionl.:;l structure. \'ith later basic doleritic dykes. strata re,cmble The as\ocj~ltecl hasic dykes tend io follow this regional v!athinna Beds or N.E. Ta51nania (Silnro-Devonian. SPl"': tr~nd. petrological eX~Hl}lnation (F.L.S.) llle! Banks. 1962). postulated that these suggesls ihat the are rnajnly near-shtUl'a ted dolerite lcds are folded along the Furncatlx ';imilar dykes intruding the Palaeozoic base \nticlinorium, but most of the strike, on the Barren Island and in eastern 'J asmania ~land by Blake (1947) and the aUlhors were NNE-·SSW nod 1962. p.283). They arc o NE-SW in trend. Bores show thai these bed" extend in age. UHler Cainozoic deposits around Whilcmark 959b). Granite forms most of the exposed CAlNOZO.IC STRATIGRAPHY :ommonly in bold outcrops and ~omctjmes including The Cainozoic rocks inelmle marine, JiHoral, estuarine, legmatitie and apiitic phases (Flinders, 11' 14; Strzdecki, ;Ieolian, alluvial and residual sediments, with volcanic 1845; Gould, J872; Johnston, J.879; Blake, 1935, 1947; ilows and pyrodastics. They a re generally undisturbed everard, 1950: Carey, 1953; Hughes, 1959a). It is tectonically, and the probable succession is summarised 'cgarded as an extension of the granite of N.E. Tasmania, in Table J. ntruded after the Tabbernbbcran Cnogeny (Spry and 3anks, 1962) and dated as Late Devonian (370 m.y.; TEUnAirk' NON·]V1[ARINE BEDS v[cDougall and Leggo, 1965). Gravels, grits, s'll1ds. clays and lignites up to at least Recent preliminary investigations of the granitic rocks 6 m. thick, including stanniferous deposits, rest on the ;llggests that there are at least nine petrological types Palaeozoic basement of the Island (Blake, 1935, 1947; D. L Groves, pers_ comm.). Tile iargest area is covered Keid, J 949; Jack, 1966). The lower levels of these

T.idlLE I. PROBABLE STRATIGRAPHIC SUCCESSION, FLINDERS lSLAND.

JPPER HOLOCENE ,- LACKRANA SAND (modern harrier growth). Alluvium. lagoon, heach and dune 1 bone deposits. r---LliGHRATA SAND. PETRIFACTION BAY COQUINA (post-glacial maximum sea?) lOWER HOLOCENE i,- NALA SAND ('Old barrier reorientation). Ranga cave bone deposits. Tektite shower (?)~l

--?---?------_.. - Frontal dunes & old harrier ridges. LOCCOT A GRIT. Lagoonal limestones. Tas- .1' manian Aboriginal migration? EAST RiVER COQUINA and correlates (4.5 m. sea?; old barrier growth). I UPPER PLEISTOCENE MARSHALL BAY COQUINA (15 m. sea?) LIAPOTA SAND. Al.TMOOR • SAND. PETIBELA SAND. ---'1----?------.------r -Tro1lsers Point acolianite (,Helicidae Sandstone' o[ Johnston). OPOSSllM LOWER PLEISTOCENE i BOAT HAR1301JR GR1T. "( ----'1---'?------, PALANA I IMES'J ONE (older to younger dum's). MEMANA FOHMATION (Wcrrikooian sea'?). Stmmiferolls beds. UPPER PUOCENE --?---7------CAMERON INLET FORMATION (post-Kalimnan·Maretimo s~a'l) (Tllrritella I.OWER PLIOCENE ? limestone' n[ JohnwJn'?). -----'1---.--'1 ------'Kalimnan &. older marine heds' (oil-shore!'? Laterilic profHes? MIOCENE TO LOWER AU OLlVINE-Bi\SAl.TS. OLIVINE-NEPHELlNITES. 'Miocene marine beds'? TERTIARY Sub-basaltic lutTs_ Sub-basaltic & 'Lower -. Mid-Tertiary' slanniferou;, beds.

--Unconformity--·--- PALAEozorc GRANniC lNTRLlSlONS, with hasic dykes (Devonian?,l. BASEMENT MATHINNA BEDS (Siluro-Devonian?)_ 154 THE CAINOZOIC GEOLOGY OF FLl]\DERS ISLAND, BASS STRAIT

LEGEND MARINE FORMATION

C(l",e~on. Inl. t F07mo.tian SeC.& UT (UppeTTe~l'M!:J)

Inlan.a BOLlnda.~" of bposu",s (App'ox. Uppe~ T/'thQ'.'J Sho1e) + i'1erna.na, FO~rrtatio,,- Site L P (Lo,,,e,, Pleistocene)

++H+ Inland BOLlnda't!J of Expo.uTe, (App'tox. Lowe" f'leLstocene ShOTd

x East Rev,,'\'" COi"'no. Site U P CUppe'\'" PleLstocene?)

lolo.ncl Boundo.'t~ of Expos'n~. (A pptox. Uppe't Plelstocene. ShO"l'<')

Ma'YshalL Ba.:! Co~uLnQ. Sae (PleLstocene)

.. Tanne1" Ba.~ Flow 2

3 Po.'t1~S ['''','J Flow Leven ffto"p<, Flow 5 Ro."SQ. Flow 6 Vlhilemo.'tk TufF 7

Associ~ted PI.ow Remnants

Fig. 2.~--Distribution of Cainozoic vo1cank fealures and marine formations on the Palaeozoic base ment. Flinders lslancl. Bused on field work bv P. L. Sutherland, R. C. Kershaw, T. A. Darragh. D< .M. Shanks and l--L E" Wilkinson: F. L SUHIEl·--Chew robacco Creek area. sediments 'on Cape Barren island are dated palyno The basalt is massive with cooling columns west along logically as Upper Oligocene/Lower Miocene. while post- Adelaide Bay, but becomes strongly vesicular and basaltic material from 3.3 m. depth at Tannen, . amygdaIoidal to the east and at Chew Tobacco Creek. field is tentativelv dated as Pliocene-Pleistocene Vesicles are coated with yellow or blue elay or sub 1965). Sub-basaltic stanniferous quartz boulLler. grit limate and amygdales commonly contain carbonate, often 2]ay deposits arc known at Canns Hill loco ci1.l. forming botryoidal radiating masses weathering to Some beds are pyritic and native sulphur recorded from limonite. Tertiary sandstones on the Island (i OA%S: Tasrn. D~,pt Petrologically [he basalt resembles M.ines, 1970). ncar saturated alkali of Tasm;nia (Suther- TERTIARY VOLCANICS land, (969). It may !lave erupted from the explosive centre near Samphire River, probably flowing over a Restricted outcrops of alkali olivine-basalts and olivine fiat coastal plain extending to below present sea-level. nephelinites represent a number of small iso[,!led H is overlain by undifferentiated Cainozoic sediments, eruptions. The thickest and highest exposure is 15 m. Pleistocene Altmoo! Sand and Recent Petrification Bay of lava N. of Ranga at 120 111. elevation, and the other Coquina, and forms some lateritic soil W. of Samphire exposures lie on the coastal plains. Outcrops show rough River. See Addendum for jurlher evidence of age. N.W. alignment with some cross trends, and some eruptions were explosive. The centres appear to be (2) Ranga-Whitemark area. located mainly along Tertiary fault trends or near Massive basalt overlies a deep lead at Canns Hill here intrusive granite basement contacts (Figure 2). (Blake, 1935, 1947) apparently filling a N.W. trending Basaltic turf containing numerous silicified logs was valley. Outcrop pattern and basement topography suggest reported near Badger Corner (Johnston, 1879). This that this valley partly follows a N.W, fault line. A occurrence was not relocated, hut small patches of strong E-W lineation, probably a fault, crosses the weathered tuff (1966:34:14) were noted under basalt southern part of the Darling Range and would intersect below high-tide level around Samphire River and this line below the highest basalt. inferring location of 0.8 Km. E. These contain subrounded fragments of the vent OIl such cross faulting. tachylytic basalt up to 0.8 mm. across and fafe weathered Petrologically, the basalt is undersaturated alkali reridotite OJ fragments. Silicified wood collected on olivine-basalt, rich in giomeroporphyritic olivine and the shore in this vicinity was one species referable to titan-augite and approaching a picritic type (Appendix 1; (he Melaleuca (ident. A. Baker). Basallic tuft: was Analysis 1 Table 2). It is distinct from the Adelaide encountered in a bore at Whitemark Hotel, 4.5 m. Bay flow, hut its age relationships are obscure. It is below sea-level overlying limestone (Hughes, 1959b), overlain bv Pleistocene Pahll1a Limestone and Altmoo)' and petrological examination (Appendix 1) suggests " Sand and - appears to be lateritiscd (Pliocene?) near possible hyaloclastile deposit. Ranga.

TAIlLE 2. CHEMICAL ANALYSES & C.I.P.W. NORMS, FLINDERS ISLAND LAVAS. ANALYSIS 2 NORM 2 SiO, 43.16 41.85 Or 6.50 12.47 riO, 1.71 2.66 Ab 13.12 12.16 ALO, 10.99 11.01 An 14.89 3.21 Fe,O, 4.13 4.90 Ne 5.00 14.46 FeO 8.67 8.75 Di 17.32 17.85 MIlO 0.21 (US 01 30.1 J 20.79 MgO 16.17 11.88 Mt 5.99 7.10 CaO 7.95 857 !l 3.25 5.05 Na,O 2.64 4.59 Ap 1.02 6.01 K,o 1.10 2.11 Ca 0.27 P:.O, (}.43 2.75 Other 2.24 1.03 .H,O+ 1.R6 1.03 1-1,0- 0.38 CO, 0.12

------~~"-----.------'-'-' -,~-----.-.---.------_._._--_._----- TOTAL 99.40 100.40 99.44 100.40 I. Alkaii olivine-basalt (picritic phase), N. Ranga. Flinders Island; F. L. Sutherland, analyst. 2, OJivine-nephelinite (with periciotitic inclusions). N. Lughrala, Flinders Island; E. Kiss. analyst. !56 THE CAINOZOIC GEOLOGY OFFLlNDERS ISLAND, BASS SlRAI1

(3) Tanners Bay-Boat Harbour--Palana areas. Preservation Island (Tas. Nlus. Colln. Y62.9; P. G. Quilty .. Small poor basalt exposures in north Flinders Island pel's. comm.) are unknown on Flinders Island, but may occur near Tanners Bav and in drill holes to the north have heen removed by erosion, or become covered, 9 m. below late Tert{ary-PJeistocene sediments (Jack, Derived foraminiferal faunas of probable Upper Miocene 1966; f). J. Jennings, pel'S, comm.), as pebbles brought age in dune limestones at Ranga (described later') to the surface by uprooted trees in dune limestone near suggest the former presence of sLlch marine beds around Boat Harbour (co!L W. F. Ellis). and as float S,W. of western Flinders Island, Fossil I1sh teeth, washed up on Pal ana. The rocks are dense to amvgcbloidal alkali the east coast suggest Miocene-Pliocene marine beds off olivine-basalt, sometimes carrying small peridotite xeno shore there. These include a right mandibular tooth of liths and accidental xenocrysts (Appendix 1). The question Edap/wdoll swceti (1966:39:1; coIL H. 0, Clifford, 196.3; of sepal' ,ne extrusions or their sollree is uncertain from ident. T. Scott), recorded from basal Kalimnan in Vic, present .oxposurcs. toria (Chapman and Prilchard, J 907), and a tooth of (4) E.. Mt Leventhorpe arca. Caraclwrodoll tnegalodol/ (1966:39:9: height 11.6 em" Small poorly exposed resiJua 15 of dense massive basalt hreadth 9.g em.; colI. F. Henwood, 1914), recorded from here su ggcst localised extrusion of undersaturated Janjukian, Balcombian and Kalimnan (probably derived) alkali olivine-basalt (Appendix 1) onto the eastern in Vieioria (Chapman and Pritchard, 1904), coastal plain. Tertiary marine beds were apparenrly penetrated il\ Olivinc-Ncphclinitcs Wingaroo No. 1 Bore, in shell beds between 3-24 m. depth. within alternating fine and coarse sands con Outcrops of dense dark fine grained rock on Parrys Bay shore and tioat near Lughrata represent separate taining almost perfect shells (Nyc, 1931). The fauna extrusions of olivine-nephelinites (Appendix 1; Analysis from 17-24 m. depth (Table 2) includes Ty/ospira 2, Table 2). The Lughrata rock lies wilhin granite base cO}'(Jnata, Turrirella (Colpospira sp.), li1i/tha flindersiana ment, is found as pebhles in overlying Pleistocene Palana and Placamell cf placida (Singleton and Woods, 1934; Limestone, and contains numerous small peridoti!ic Wilkins, 1962b; Gill, 1962; Ludbrook, 1967). Singleton xenoliths and xenocrysts in comparis'On to their relative and Woods considered that the faunas were very late rarity in the Parrys Bay rock. Tertiary and the proportion of Recent species listed suggests correlation with the Cameron Inlet Formation, Discussion possibly passing up through Maretimo into Werrikooian and younger horizons above 17 m. depth, Comparison Ages of the Flinders Island volcanic rocks are not well of species at different horizons in the bore (Tables 3 esta blished, but stratigraphic evidence suggests that most and 4) with the present day fauna, suggest a lagoonaJ are pre-Pleistocene and probably Tertiary. They fal! shore to near-shore sandy to sandy mud shallow water geographically between the Victorian and Tasmanian facies down to 17 m. depth (Kershaw, 1(58), in keeping basalt provinces. They form an alkaline suite resembling with eastern Flinders Island today. Below 17 m. [he the Older Volcanics of Victoria (Palaeocene-Lower fauna suggests a similar facies, but with reduction of Miocene; Singleton and Joyce, 1969) and the alkaline exposure as found in semi-sheltered bays. basalt associations of Tasmania (Eocene-Upper Caino zoic; Sutherland, 1969), both of which extend to opposite Cameron Inlet Formation (Darra!;ll and Kendrick, 1970), coasts of Bass Strait adjacent to Flinders Island. This Pliocene formation was originally described by The lavas range from strongly undersaturated alkaline Wilkins (l962a) from The Dutchman lime quarry (grid rocks (0 mildly undersaturated basalt Such rocks have 546N-028E, Dutchman Coquina) and from Nelson been tentatively interpreted as products of segregation Lagoon Drain (grid 612N-040E, Cameron Inlet Mar]), of parent alkali basalt magmas at depths of 35-75 Km. It is exposed in quarries, bores, drains and waterholes under Tasmania, with the nephelinitic mollusca (Table 3; Plate 1, fig. 1) and N.W. Tasmania (Lower Longfordian; Quilty 19(5), but extended down from 6.5 m. ahove M.HWS. Wilkins considered that most snecies were different It may (written comm., 1958) remarked '1 don't think anyone represent the Cameron Irilet Formation of Middle-Upper has yet noticed the horizon of phosphatic nodules at Pliocene age (Darragh and Kendrick, 1970, and herein), the lime quarry. Also associated Lovenia ... and cidaroid or possibly remanic forms in the overlying Lower spines. These 1 found around the deepest excavation ... Pleistocene Mcmana Formation. The nodules represent a diseonformity of some sort and are comparable to the nodule beds in Vicloria, Bryozoal and. cidaroidal marine limestones of Miocene though they look only faintly phosphatic', A chemical age on Cape Barren Island (Crespin, 1945b) and analysis 01' the coquina gave 81% CaCO" and 0.[2% F. L. SUTHERLAND AND R. C KFRSHA'W 157

TAIlLE 3. PLIOCENE MOLLUSCA, CAMERON iNLET FORMATiON, FLINDERS ISLAND

...... ------_. __ ._ ... _-- . - ._._-_ ....__ ._-_._-_._...... - ...~------.-- Dutchman Nelson N. Patriarch Wingaroo Molluscan Quarry Identifications Lagoon -Memana Bore N°-l Drain A.rea 17·24 m.

--- -_... -----_.. GASTROPODA Alocospira afl. marginata (Lamarck) x -_ ..._._._._-----_ ..•.•.. _------.. - Amorena Illldulata (Lamarck) x Bankivia cf. fascia/a (Menke) x x i-· Callcellaria sp. x Cassis (HY[Jocassis) fimbriata (Quoy & Gaimard) x Ctenoco[pus austrulis (Lamarck) x

-_._------~----- ._------_._---.-._- C. terehellatas Crate) x Cupidoliva nymphala (Tate) x Ericusa papillosa (Swainson) x Eugyrina sp. x Floracollus anemone (Lamarck) x Fusus novae hollandiae (Reeve) x Gazameda gunni (Reeve) x Leiopyrga qlladricinglliata Tate x Phasial1otrochus sp. x Pho,s. sp. x P. senticosll.\· (Linne) x Polin ices conlwel' (Lamarck) x P. afL cunl1inghamensis (Harris) x Sigapaiella calyptraefonnis (Lamarck) x -_. Te·rebra sp. x Turbo (Subninella) sp. x Turritella (CoJpospira) cf. pagodula Tate x T. (Ctenocolpus) ct. conspicabilis Tate x Tylospira coronata (Tate) x x x T. (Singletonaria) gilli Marwick x U mbilia hesitata freLble x '---._ .. ------PELECYPODA Bassillf1 alf. pachyphylla (Jonas) x B. cf. pallcirugata (Tate) Cardium sp. x Chlamys ct. asperrimus (Lamarck) x 1----·,·-...- --..-.- ...-- Cucll//aea praelonga Singleton x ,* x Divalucina cuming! (Adams & Angas) x x Douacilla erycinaea (Lamarck) x Dosinia sp. x Eucrassatella de/toides Darragh x x* E. memanae Darragh x Eumarda sp. x 15R THE CAINOZOiC (JEULOGY OF FLlNDFRS ISLAND, BASS STRAIT

Table 3. Pliocene Mollllsca. Cameron Inlet Formation, Flinders IsJanu tcofl[lnlled)

Dutchman Molluscan Nelson .N. Patriarch Wingaroo Quarry Lagoon ! lknti fical ions "Memana Hore N°·1 Drain Area 17-24 m.

E. ct. fUlIligala (Sowerhy) Gari aIf. kl!llYl!niww (Prilcha I'd & Gatcliff) x GlycYlIlcris COI/W.W Cbtc) x x* x x G. halll Pritchard x x x Homlllilla cf. mariat' (Tenisol1 vVoods. 1 fi75) Kalf!iysia I'hytiphora tLamy) x K. peronii Lamarck x Miltha Jfindersi'ona (Singleton & Woods) x x Neotrigonia ef. margaritacea (Lamarck) x Notocallisla d. king! Gray Os/rea sp. x x O. cf. IIngosi Sowerby x 1---"----"------"------""--- "- -"------O. arenicoTa (Tate) O. afl'. manubriala (Tate) Phacosoma cL coerulea (Reeve) x Placalllcn sp. Placam(,tl cf. placida (Philippi) x x ProxiciIione moontiame Darragh x SCl1eoleda c/'LIssa (Hinds) x Tawe/'il sp. Tucetilla radialis (Lamarck) x

Identifications by T. A. Darragh, E. D. Gill and shells only from the basal marl. M alerial includes Tasm R. W. T. Wilkins, with Wingaroo Bore No. 1 mollusca Mus. CoHn., Z 1371-1373, 1448-J475. R. M. Johnston modified from Everard (1950), and some species listed (1879, ] 887) lists the following amended species from from Darragh (1965), Dorman (1966) and Darragh and the Tertiary beds of Flinders Island, but their exact Kendrick (1970). Asterisks beside Nelson Lagoon Drain status is uncertain; Cllcu!laell (CuclI/!ea) corioensis, material indicates shelJs found both in the basal marl G iycvmeris (ClIclillea) coinoz:oicil. NuclIla f{{mida, and 'Overlying beds, including remanie forms in the Turri/ella sp., Roxania (Cyiichina) woodsi and Pleistocene East River Coquina; lack of asterisk indicates Diplodollta slIi>qllucil'llla.

---~-.------_.. ------.. - ---.------~-- ---"------.----.------~-.--.~--~-.------_._-----_._--

P,O;,(Everard, in Hughes. 1957). Matrix from the top angular quartz grains up to .'5 mm. across; it sometimes of the coquina contained Glandillina kaiimnensis Parr forms hard calcrete. (common), Rotalina lwmiltol1ensis Parr, Nonion vic/or The type exposure in the extreme N. end of Nelson i{,llsis Cushman, Massi1in({ laridigem (Howchin and Pan) Lagoon Drain was a 0.6 m. thickness of green glauconitic and an assemblage of large miliolids, polymorphincs and shelly marl, stratified as follows m. W. "f. Wilkins, rotalids, with many small lagcnids, suggesting shallow written comm.): water hut open sea conditions (A. C. CoJJins, per E. D. a) 15 em. ClIclIllaea horizon. Gilt. pel's. cOInm.). Broken and separated bivalves in the 0) 23 em. EZlliwrcia horizon. upper part of the coquina suggest possible reworking c) 23 cm. Cucullaea horizon, with mixed 'rolled' and of a shallow water, near-shore deposit. Lateral equiv 'unrolled' shells. to waler level; the top of the horizon alents to this reworked top of the coquina are apparenlly was apparently eroded and bored and may have been exposed in waterholes O.S KIn. N. and up 1'0 2 Km. E. exposed as old beach rocks. The position of this horizon to S.E. Here, the matrix varies from a gravelly quartz has been stndicd further south in the Drain Section, grit or sand, mixed with abollt 20% calcareous delritm. O.R Km. N. of East River (grid 550N-0.50E), where the to predominantly calcareous detritus with rounded to succe.'sion (Plate 1, Ag. 2) is: F. L. SUTHERLAND A1'D R, C KERSHAW 159

a) 004 m, lagoon soils with freshwater shells Oll tht: erosion of tbe m"rine beds i:; uncertain un present lriace, exrosures. The sJnall inswing in the Formation's dis b) 104 m. sandy subsoil with grit (Nala Sand and tribution E. of Mt Leventhorpe, and its apparent 'possum Boat Harbour Grit?), absence on the sOllthern coastal plain may correL,re with hasalt {lows in these areas tending to act as harriers 10 c) 0,3 111, shell bed with numerous Quaternary shells the marine incl1l'sioll, '1d remanie species from underlying beds (East River oquina), The palaeontological cvicknce suggests that the Cameron inlet Formatiou is MidJle to Upper Pliocen", d) 15 cm, shelly sandy bed. in age (Darragh, 1970 and herein), Wilkins (I %2a) e) 30 em. sandy bed, assigned a prohable post-Kalimnan. pre~Mgenus Ziphius (Plate 2), but Mcmana ~Formation iffering from any Jiving species (1. Moore, per J. W, 'an'en, pers, comm,), Rare coral includes Plesiastraea This Formation appears m thc North Patriarch area I(Jl1as (Ellis & Sol:mderl and p, cf, Vi"rsipora (Lamarck), (Figure 2, Plate l. fig, 3) outcropping through, and \;Ont. M. R. Banks, from excavations passing into encountered in excavations in soils of the Mcmann liocene beds at Lackrana and near North Patriarch Association (Dim111ock, 1957). It lies lip to 5-7111, above rain, but the exact stratigraphic location is uncertain, MHWS and is at least 4.5 Ill, thick. 'rhe following general follccession was established at the E. end of No, The eastward sw ing in distribution of the Cameron 11 Road from excavation debris and communication llet Formation between Meman,l and Lookout Hill w1th the property owners. "igure 2), is inflnenced by the alluvial deposits of a) smface gravelly or loamy sand, up to (),6 m, thick. eventhorpe Creek, Drain and dam excavations (to 5 m,) and bores (to 27 m, deep) in this area do not b) clay horizon, 5-30 em, thick. Jemmter the shell beds penetrated jusl to the cast c) hard coquinoid calcrete or calcareous bands and (hether this is due to the existence of the alluvial nodules, 15-45 em, thick. til as an original Jand barrier during the marine d) gravelly and gritty shelly sands and sandstone, up Er()~ition Of whether it results from laier Pleistocene to 1,5 m, thick. TABLE 4. QUATERNARY MOLLUSCA, MARINE BEDS, FLINDERS ISLAND. (LOWER PLEISTOCENE-RECENT). ~ ~,

Coquina. 'Oyster Marshall East Arthur Red' Wingaroo of Petrifaction Somh Coquina. ]VIo)]uscan Identifications Memana Bay River Trousers Bay Trousers Yellow River Johnston, 0--4.5 Formation Coquina Coquina Pt Coquina Pt Beach Estuary 1879 GASTROPODA

A cmea scaiarinl1 Cox x x* X A AmblychilepilS crucis (Beddome) X '-i ~ A murenll rmdu/ma (Lamarck) x X IT ..- ~-.- Assiillinea tasmanica Tenison \Voods x !", ~ ASleic slIbcarillutlim Swainson x x " -- ---..- ....- C: Austrocochlea sp. x ...- -- 8 A. adelaidae (Philippi) X .~ c ------~ - A. COl/camerata evV'Ood) x x v C'! t:; A. L'onstric!a (Larrtarck) x .f';, X j:::, C' A Ilstrodrilfia "eral/diana (em.sse) x c) _. ------,-< A listroginelfa mllscaria (Lamarck) x* x Bankivia fasclata (J\lenke:l x X:f x en ------"._------.--.~-.~-.- Bartiluridla est Chcmnitzia mariae Tenison \'loods v; x '" Chia~acmea fhlmlllea (Quoy & Gairnard) x Cl! '''1 Cing;ilina spina (Crosse & Fisher) x

- .. ------~------.------.------~----"------_... _------~ Clailcu!us plebejiiS Philippi ;;: --J ComilZol/a eburnea (Reeve) x Comillelfa sp. x

~----.------.. ------.--- --~-----~-. Coniedla porcellana (Tate & May)

------~-----~------~~-~.-----.------~------.. Coxiella sp. N .M. i x I---~ ... -----.-.------. ..-.---.. -----.. -----.-.----- .----.---.. -.... - Ctelloco!plIS australis (Lamarck) 1__ x ______. __ ~ ______~ ----______.. _____ .. Cylic/zninil sp. x I ------~------~------C. iredaleana (Hedley) x x

.~.--~----~----- . i=:~ Cymatielia verrucosa (Reeve) I1-- --- Dentimitrella sp. 1-I x* - - x . -- -- D. lincolnensis (Reeve) ------~~--~ D. mcnkeana (Reeve) x D. fay/oriana (Reeve) x* Diala lauta Adams x x x D. pagodula Adams x*

------~------Eubiltium lawleyanum (Crosse) x x ----- Flo/'aconus anemone (Lamarck) x* fI erpeto.poma sp. x HypotrochuS' mon(lclius (Crosse & Fischer) x* lsoc!anculus dunker! x x 7J :--.-.~------~----,------.-.------r Kimberia sp. x '"c:: Lenamaria cf. nitida (Sowerby) N.M. :-J Macrazafra atkinson! (Tenison Woods) x x tTl Mesoclanc!us ochroleuclls (Philippi) ~ ~ x Z M icrastraea al/rea (Jonas) t;I Microcolus dunkeri (Jonas) x ~ -~ ,'1unditia australis (Kiener) x v Nassarius sp. ~ ~ Nevia spira/a (Lamarck) x o ~ x x x x tr; Niotha pyrrhus (Menke) ;;0 Notocochlis sp. x '";r: :> Notosetia sp. ~: \- N. nitens (Frauenfeld) 1__ x x ------_._-- Ophicilrdelus sulcatus CR. & A.. Adams) I - x------Parcanassa pauperata (Lamarck) x x x Pel'1'icacia lIstulata (Deshayes) x Phasianella australis (Gmelin) x Phasianotl'Ochus irisodontes (Quoy & Gaimard) x x PlcHroplo.ca australasia (Perry) .X

------~-----~.---- Pficaginella sp. x x Polinic{;'s coniclls (Lamarck) x Proxiuhe:" sp. x x* Pseudamyda dcrmestoidea Lamarck x' 0\ TARLE 4. QUATERNARY MOLLUSCA, MARINE BEDS, FLINDERS ISLAND ~LOWER PLEISTOCENE-RECENT-continued) 0''"'" 1,0 Coquina, Coquina, Coquina, 'Oyster Petrifaction SOllth ~ f Marshall East Arthur Bed' Wingaroo South of Coquina, Molluscan Identifications Memana Bay River Johnston, IJ.-4.- ) nl~ Tl'f\nCMC BIlY Tromel's y",\low Formation Coquina Coquina RiYer Coquina Pt Beach Estuary 1879 y[ ~~~ __ ,,~~~~(lagoon)

PyraZils sp. ~ x' P. ebeninils (Bruguiere) N.S .

. --~,-.""-,-,,-.""--. -----, Salina tor jragilis (Lamarck) x

"'----''''''~-'''-,~''''------~--,,~~~~~- ..., ~-.- Sigapatefla caiyptraeformis (Lamarck) x x' ~ rn Sydaphera purplITllt'formis (Kuster) x n. >- Tavaniotha munieriana (Crosse') x L Turriteflll sp.? x ~ Zeaclimanfus cerilhium <. Quay & Gaimard) ;;; ~ '"' Z. diemencnsis (Quoy & Gaimard) x x x x o

--.-.-~.-.~~.------~-~------. -~----~ PEI.EGYPODA 2 ~ Alllldara trapezia (Oeshayes) N,S, c:' -: Anapella cycladea (Lamarck) x x Bellucina crassilirata (Tate) "" Ghlamys asperrillllls (Lamarck) x x x' F i""" Z Godakia sp. v x2 ------~----~------.--~ IT; Cllspidaria sp, ~ 'fl i-,,,,,,--- ,-..--""-~""-"""- .. -~- ----"------.~.- Divalucina cumingi (Adams & Angas) x H vc :------,~""'---. ---~'''''''''- t'" Donacilla angusta Reeve x > i"" ~ [)" {,lIlleata (Lamarck) x x x !=' Electromactra antecedallS Iredale X tt1 )0- (J) Eqllichlamys bifrolls (Lamarck) X x* x (J) Elilnarcia fumigata ? (Sowerby) X' Vl Fulvia tenuicostata (Lamarck) x x x x ;::~ Glycymeris sp. x' G. f/ammeus (Reeve) -i---· HOll1alina deltoidalis (Lamarck) x x H, !IIariae (f'enison Woods) i--'''''-'''' x Hormomya erosa (Lamarck) I~-=~_=~=-_,,·_x______x x x x Katelysia peroni! (Lamarck x x x K. rhyripllOra (Lamy) I_~""_,_,, x* x x' x x K. scalarina Lamarck x

~~~~~'''~-~~-----~-~~-,,--,,--''''-,-,,---~ c.; KeWa iluotralis (Lamarck) 1__I .___ x Latemula creccina (Reeve) x i Limnopsis sp. I i--.- Lutrar!a rhynchaena? Jonas I-:-_~ __ :: .. __ x Mactm pura Deshayes ,'v1. rufescens Lamarck i . - - x --_._-_._----_ .....__ .--._ ... lHodiollis pulex (Lamarck) x Myadora brel'is (Sowerby) i x Mysel!a sp. I- Myrillis planulatus (Lamarck) I,._ X x Neotrigonia margaritacea (Lamarck) 1_ x Norocallista disrupta (Sowerby) x -.--~- .•. -~ --~--.~--- "-_._------_. _ .. ,------"---_. -._------!i NotospislIfa trigoneTia (Lamarck) x x x x Ostrea sp. x '" O. af/gasi Sowerby x ~:r ------. .--.--.. ----.. ------~.------.---.-.- tri Phacosoma coerulea (Reeve) x '" Placamen /Jiacida (Philippi) > x Z .. -----.. ~.----.------.------~------Pselldarcoplzagia victoriaI' (Gatcliff & v Gabriel) x x x > ------Z Scaeoleda crassa (Hinds) :::J ;:0 Solell l'aginoides (Lamarck) x So/etellilla bil'adiata tWoodl x 71 Tawera !{al/il1u/a (Lamarck) rri -_... ---.--_. -"~--.------;c:"" T /agoplls (Lamarck) x x );: ---_._---,,- .-._---._------_.... ---- T. stria/ularis (Reeve) x x :::

------.. -----~ .. Zemyria cf. globosa (Adams) x Zenatiopsis ultima Darragh & Kendrick x -._----.. _---_.... __ . __._ ..--._------

Identifications by R, W, T. Wilkins, R. C. Kershaw, E. H. Turner and T. A. Darragh. with listing from Nye (1931) and Darragh and Kendrick (l970). Material listed under 'Oyster Bed', Johnston. 1879, was identified by R. C. Kershaw from Johnston's .Arthur River Estuary Collection (some labelled Oyster Bed), held in the Tasmanian Museum (amongst Z861·Z917). N.M, against molluscan species indicates a nOD·marine dweller, Asterisked species from the East River Coquina indicate shells found in the type section in Nelson Lagoon Drain. Specks numbered I and amongst the Wingaro'O mollusca indicate shells found in the 0-3 m. and 3·4.5 m. depths respectively in the Wingaroo Bore (Nye, 193 ). N.S. indicates shelb found not ill sitlL .Material includes Tasm. Mus. ColI. Z1476·1539. R. M. Johnston (1879) lists the the inland sand dunes and Jagoons of Flinders Island. but their exact status is uncertain; Bankivia iasciata Neotrigoniu (Tl'igonia) marguriiacea Tlicetilla (Pecumcillus) strlatu/ar!s? (!'IIbells), T. (P.) radialiS: (rOstIlS), Sulinafor (Ampullal';l/a) tragi/is. A nadam (Area) trapezia, Scacoletia (Lt'da) Cl'Ilssa, Fulvia (Cardium) tel1u.icostala (Iellllicostatum), Glycymeris (Cucul/ea) cllino:;oica (remanile), Gly cymer;s (Pecllmel/ius lazicoslatus (remunie:'). Cucullaea (Cucu.'lea) co.rioensis (Felnanile'), Examples of the modern molluscan fauna of the Fum· ""0', eaux Group are listed in Johnston (1879), May (1958), Turner (1970) and the Tasmanian Museum Molluscan Register. vO 164 THE CAINOZOIC GEOLOGY OF FLINDERS ISLAND, BASS STRAlT

TABLE 5. FORAMINIFERA, QUATERNARY DEPOSITS, FLINDERS ISLAND

Formaniferal Identifications

Ammonia heccarii (Linne) x x A 11011Wlil1(1 sp. x eihicides mediocris (?) Finlay C, ref/llgens (MontforfJ x C. victoricnsis cn Cushman xR Clavulina tIluft/camerata Chapman Discorbinella bicollcava (.Tones & Parker) x x Discorbis dimidata (Jones & Parker) x x? Elphidium adv(,l1um (Cushman) x E. argenteum Parr x x x E. crossa/um Cushman xR E. erispum (Linne) x E. macellum Fichtel & Moll x x x c/. Epistominella Jiulchra (Cushman) x Globigerlna bulloides d'Orbigny x Globigerinoides cong/obulata (Brady) xR Guttulin([ yabei Cushman & Ozawa x M iiio.linella oblonga (Montagu) x N onioll victoriense Cushman xR Operculina victoriense Chapman & Parr xR Parrellina ill1peratrix (Brady) x Patellinella incollspicua (Brady) x Polystomellina clathrate (Brady) x Quinqueloclliina lamarkianll d'Orbigny x Rectobolivina sp. x Rosalina llilstm/is (Parr) x x Spiroloculina llngulata Cushman x x S. subimprcssa Parr x x Streblu.I' beccarrii d'Orbigny x T eX/lIlal'il{ sp. x T. pseudogramcn Chapman & Pan x x Triloculina striatula Parr x x x T. trigonaLa Lamarck x

Identificatiolls by Crespin (1945a), Ludbrook (1965) and D. J. Taylor. R. indicates probable remanie species. p, L. SUTHERLAND A."

e) shelly silts, soft sands and limestone, 1.5-3 m, thick, River between 2 .. 3.5 m. above MHWS. It disconfofmably f) hard gravelly and gritty coquinoid limestone, at 'OverLies the Cameron Inlet Formation and is discon [,2-4,5 m. depth. fonnably overlain by at least J.7 m, of sands and The basal coquinoid horizon (unit f) contains numerous lagoonal soils, including Nab Sand and Opossum Boat vorn shells, including remanic Pliocene species, associ Harbour Grit ('7), (Plate 1, fig. 2). ted with well preserved Bankiv!a j'asciata and appears The fauna contains numerous Quaternary shells (Table o represent a near-shore or littoral deposit. It is found 4) and remanic species from the underlying bed (Table t shallower depths to the south and eventually the 3) mainly in a mixed transitional zone to 8 em. thick. ,orizon gives way laterally to the underlying Cameron Numerous marine bivalves, sometimes packed tightly. nlet Formation. include generally complete oysters apparently ill situ. The shelly soft beds (unit e) a re well exposed around The formalion top is weI! defined, but with slight -io. 2A Road, between Nos 11 and 2 Roads. The reduction in shell numbers, and no marine shells occur nolluscan fauna here Crable 4) is essentially modern, in the overlying deposits. The fauna represents a mixed lut includes rare Zenatiopsis ultima (Darragh and Ken assemblage, apparently an accumulation on a bay tloor, Irick, 1970) and some remanic Pliocene shells, and and includes species normally living on sea-weeds uggests a probable Lower Pleistocene (Werrikooian) (Bankil'ill), near-shore or inter-tidal species (Kateiysia, 1ge. The fauna suggests shallow off-shore bay conditions, Cacozelliana) and off-shore species (Fulvia, Eqllichlamys). lI1d some Chlamys asperrinzas shells bore growths of fn mo,t cases a sandy mud or sandy environment is larnacles (d. Balanus variegatlls, ident. E. C. Pope). indicated, but with some nearby rocks as suggested by The upper members (units d and c) contain strongly presence 'Of algal dwellers and Florocollus anemone. \forn shells and in some places resemble littoral deposits. The matrix is sandy silt largely composed of quartz, rhe succession to the N.E. thus appears to encompass both dear angular and rounded frosted grains, and ieposits of transgression and following regression of shell fragments, The [oram iniferal fauna of a basal he Lower Pleistocene sea into a large bay. However, sample included Nonio/1 victoriense, Glo.bigerinoides he role of possible later Pleistocene transgressions conglobata and several other Kalimnan species (D. J. represented by deposits elsewhere on the Island) in Taylor, pel'S, comm.), However, in view of remanie his area is uncertain, and they may have reworked part molluscan fauna, these are probably remanie Iorams )( the upper succession. The northerly extent of the from underlying Pliocene horizons. ~'ormation is not precisely known, but it extends into he Wingaroo area amongst the shell horizons overlying Other sites with numerous remanie mollusca he Tertiary beds at the 17 m. depth in the Wingaroo (including E, de/foides. Darragh, 1965) occur in water Jore (Nyc, 1931; T. A. Darragh, pel's. comm.), hole excavations E, of The Dutchman between Memana road and Nelson Lagoon drain. and these excavations Vlarshall Day Coquina include shark's teeth and Whale vertebrae (1966:39:7; rhis coquinoid siliceous calcarenite is poorly exposed colI. F. Rhodes). Matrix from the top of such coquina ":. of Palana Road, N. of Lughrata (grid 760N-793E) contained a sparse extant foraminiferal assemblage tt about 15 m. above MHWS, disconformably overlain Crable 5, D. l. Taylor, pers. com111.). The Formation ly Lughrata Sand and apparently disconfofmably over extends S. of East River and N. to Lackrana (Figure 2). ying Palana Limestone. Traces of similar shelly rock lave been noted elsewhere around Lughrata lD. 1. The Coquina may be an off-shore Pleistocene marine deposit, probably related to the 4.5 m. level (MHWS), ~,roves, pers. comm.). correlated with the later Riss/ Wurm Interglacial. It contains up to 25% worn and broken mollusc Precise elating awaits more detailed investigation. ;hells, and the molluscan fauna (Table 4) suggests a Erosion of underlying beds by such a sea is indicated )each deposit with sheltered sandy bay environment by the rcmanie fanna, and similar erosion occurs common Honnomya erosa, Katelysia peronii), with sand off-shore at present as Cucullilea valves commonly wash lats (Donacilla, Notospisulaj and shallow water olf-shore ashore. However, the presently exposed disposition of 'lith sandy bottom (E/ectromacta, Pseudarcoplwgia). The the Formation is also compatible with possible marine natrix is greyish fawn, tough, compact calcrete, flooding of an elongate coastal inlet through Cameron ,\feathering white. It contains shell fragments, worn Inlet. Probable equivalent or near-equivalent deposits :oraminifera and about 30% angular to rounded quartz to the East River Coquina include coquinas near Loccota, (rit in abundant' calcareous cement. The foraminiferal Arthur River and Wingaroo. 'auna (Table 5) was reported as ' ... similar to that iving on the sea floor in Bass Strait today ... The The Loccota deposits include an exposure in an old Nom nature of the specimens suggests it is a 'displaced' lagoon bank, S. of Trousers Point (grid 419N-894E) 'auna, but the specific content does not indicate that it with a fauna (Table 4) rich in Fulvia tenuicostata s derived from Tertiary sediments' (D. J. Taylor, pers. (1965:38:76) in a friable darkish sandy silt matrix. '('he :omm.). deposit is u'p to 1.5 m, above MHWS and is interpreted The rock probably represents a littoral depo,it as an off-shore facies in situ on a shallow sandy mud Issociated with a 15-18 m. level (!vIHWS). The fauna, floor of a former Pleistocene Interglacial or Interstadial :Jegree of lithification and elevation suggest a Pleistocene sea bay. A further coquina at similar elevation, in a Interglacial age, probably not younger than early drain S. of Ferguson Jetty (grid 472N-896E), contains Kiss/WitI'm. common Anapella cyclyadea, suggesting depositi'On on sanely mud flats in sheltered to estuarine waters. The East River Coquina matrix here is now tough, light coloured sandy calcrete fhis coquinoid sandy silt, 30-3R cm. thick, is exposed containing about 30% predominantly angular quartz in Nelson Lagoon drain (grid 550N-050E), N. of East grains with foraminiferal and other organic remains. 166 THE CAINOZOIC GEOLOGY OF FLINDERS ISLAND, BASS STHAlT

A cO~11lina, o.g m. thick, is exposed in a cliff on Thus, the presence of Coxiella and brackish water the westlborc of Arthur River estuary opposite Beagle micro-fauna requires interpretation and it is considered Spit (grid 998N-R38E) at 3-4 m. above .MHWS. It dis that a brackish lagoon temporarily established on tb~ conform ably overlies Pleistocene sand (Uapota Sand?) upper shell bed of a marine transgression. This and is disconformably overlain by unconsolidated sand. transgression probably re.lates to the 4.5 m. level The coqllina may be related to the 'Oyster Bed' of (MHWS), correlated with a later Riss/Wiirm Inter J ohnstoQ (1879), which shows similarities in molluscan glacial sea. Shell beds, met at depths below 6.5-7 m. Lnma (Table 4), but which was reported ai a slightly above M}IWSunder the lagoonal soils around Wingaro,' higher elevation. A thick, tightly packed oyster bed (Figure 2; Table 4; Nyc, ! 931) probably represent was exposed in the estuary's west bank over twenty further related deposits of this sea. years ago, but has since largely washed away (J. Robin son, pers comm.) and this spot almost 0.7 Km. N. of Petriflldioll Bay Coquina the described section probably represents Johnston's This coquina, 5··8 em. thick, is exposed on Petrifaction site. The succession exposing the coquina is: Bay shore slightly aboveMHWS, disconformably over a) Cliff top, 5.4 m. above MHWS with shallow lying basalt (Plate 1, jig. 6). The coquina contains about depression of former lagoon. 600tl shell material in loose matrix of coarse rounded to angular quartz grit, with fine silty micaceous and b) blackish sandy soil with limestone pieces from calcareous detritus (1966:35:6). (c)-30 em. The shelly fauna (Table 4) is that of a sheltered c) limestone without shells---av. 15 cm. bay with sandy mud or mud, grits and stones, and is d) fine compact llnlithified sand-I.l m. the same as in the similar present local environment. The Coquina appears to be a shore-line or ne"r-shore e) white gritty sand, densely packed with 5he118--15 deposit reiated to a former sea-level about 0.6 m. above em. MHWS of probable Holocene, or possibly late f) white sand with reduced grit content, few shells Pleistocene age. Similar coquinas at equivalent including La/Nlllila in life posture-35 cm. elevations are known on the granite shore up to 2 m" g) white sand, shells densely packed-35 em. above MHWS at Palana, below the surface al Wingaroo (Nye, J931), in Arthur River Estuary and h) yellow and red-brown sands, lower levels covered near Trousers Point, but it is uncertain that they are with detritus. all equivalent deposits. The beds are exposed 50 m. horizontally and at The Arthur River deposit is exposed 46 m. along one point horizon Cd) lenses out and more than 30 em. the cliffs, N. of the 3-4.m. MHWS coquina, at 2.2 m" of limestone (c) rest on the upper shell bed of the above MHWS as a lens JIm. long overlain by 0.6-0.9 coquina (e-g). Beds are level, hut end abruptly against m. of sand to the cliff top. It contains a fauna of grey sand (Liapota Sand?). At the southern extremity Recent aspect with common ATlstromylitlL.\' erosus this sancl is sharply contrasting and contains carbon (Lamarck) and is virtually identical to that of the aceous and compacted grit bands 2-5 cm. thick. At the present sandy shore. northern extremity the sand is firstly grey, then yellow Th() Trousers Point coquina, 5 em. thick, is exposed and grey. Some mixing of materials is inferred across at the base of a fore-dune at about 1.5 m. above the near-vertical extremities, but with little disturbance, MHWS, in the bay south of the point (grid 418N- anci it seems to represent a former stream site. 893E). It contains a mixed molluscan fauna Crable 4) The molluscan fanna (Table 4) is appropriate to favouring a sandy bay with some shelter or reduction sheltered waters such as an estuary or sheltered bay. It of wave action of wide sandv flats. with Bemhicium iucludes species preferring mud (Os/rea. Zeacumantus), and Aust/'Ocochlea apparently' washed in. It includes sandy mud (Laternula, Hmnalina, KatelY.l'ia peron ii, carapace of Philyra laevis (Bell), the littoral smooth Bullaria), sand (Soletellina, Katelysia rhytipllOra) to pebble crab (1966:38:3; ident. A. Dartnell), and the brack ish mud (Batil/ariella). Hormomya lives in com deposit appears to represent a high tide accumulation. pacted sandy mud and grit with weeds as exists at The matrix is loose vellow-fawn foraminiferal cal present in Arthur River estuary, and Fulvia tenuicostata careous sand with minor amounts of mica flakes and is an otT-shore sandy hottom species. Thus, the small quartz grains. The foraminiferal fauna CfabJe 5) assemblage suggests variable conditions with some is rich, beautifully preserved and identical with those species washed in, and Nio,fha and Bedeva preying on in sea-floor samples taken from Bass Strait today, the fauna. Coxii!lla, an euryhaJine mollusc, indicates a being very similar to that listed by Brady, 1884, from marked change in conditions. 'Cballenger Station 162' ofT East Moncoeur Island in 73 m. 0-[ water (D. 1. Taylor, pers. comm.). This Sand from horizon (e) shows (A. C. Collins, per E. D. suggests an assemblage more that of an inner shelf Gill, pefS. comm.): The fioatings are almost entirely deposit with a possible depth range of 15-90 11l. and Streb/us sp. the same form as that from Lake Pertrobe. this puzzling feature may be due to a later Holocene I think, with a few rare and poorly developed Elphidium sea strand washing into Pleistocene deeper water and a lot of coxiellid gastropods. This of course deposits at this site. amounts to brm;kish water conditions, estuarine or lagoonal. I found nothing that could be taken as a Opossum Boat Harbour Grit purely marine form, suggesting there was little or no This siliceous grit, at least 8 m. thick, is exposed in influx of tidaJ waters. The sand grains are well rounded Opossum Boat Harbour cliffs (grid 430N-llOE. Plate 1, and frosted, there were a few plates of mica, and fig. 4) resting on granite basement and disconformably some vegetable debris'. overlain by Nala Sand. It is dark brown, moderately E 1.. SUTHERLAND AND R. C. KERSHAW Hi7 consolidated, friable coarse grit cont,lining weli rounded The available evidence suggests that the calcareous to subangular qnartz grains in a carbonaceous organic dunes from which the Palana Limestone developed matrix. Further exposures of such grit occur on cover a range in time. Some of the dnnes, as at Ranga. Camcron Inlet shore and underlie much 'Of the area possibly originated in the late Tertiary or early covered by Nala Sand. Teeth of the sperm whale Pleistocene when lower sea-levels associated with Physeter were found in similar gritty sand, just above glaciation would have exposed vast areas of Upper high tide level on nearby Great Dog Island ('-'011. .I. Tertiary calcareous marine beds. The limestone is cut Nield; 1966:39: 12). hy the 4.5 m. level (MHWS), correlated with the The degree of consolid"tion and devel'Opment 'Of latcr Riss/Wlirm Interglaciai sea, and this with other organic matrix suggest a Pleistocene age. Thc Grit geomorphological consiJcralions suggests a Lower probably represents detrital accumulations from erosion Pleistocene, prc-Riss/W[ilfll age for most of it of highland areas, possihly prior to, hut with extensive The Paiana Limestone appears to include a more marine reworking during. the Riss/Wiirm Interglacial silice-ous younger dune member, which may represent and/ or a Wiirm Interstadial. a separate formation on very delailed mapping. This siliceolls aeoiian calcarenite, at least 3111. thick, is QUATERNARY DUNE DEPOSITS exposed S. of Trousers Point (grid 420N-890E, Plate 1, These include extensive coastal dunes on the west fig. 5) overlying granite basement. It contains species and east coasts with some relatively small inland of 'Heliddae' and represents the 'Helicidae' Sandstone deposits. Calcareous clune deposits characterise west of Johnston (1879). Johnston's term, however, appears coast series whereas siliceOlls dunes characterise east also to partly include the more calcareous Palana coast series. Limestone. Dunes of the aeolianite outcrop from sea !evel to about 30 m. above. and were mostly observed Palana Limestone 111 the Loccota district. This is predominantly calcified aeolian calcarenite, at It is. coarse to fine grained, cross-hedded, fawny least 9 m. thick in places, occurring on the western caicaremte. it is consolidated, but friable. generally Flinders Island coast and typically exposed in the lacks the lithification shown by much of the Palana Palana, Lughrata and Ranga districts. It is variable Limestone, and contains moderate to considerable in thickness and outcrops from below sea-level to ,~mol.lnts of :lJ1gular to rounded quartz grit, with some elevations about 150 m. above. It overlies Palaeozoic feldspar and rare biotite. Samples contain reworked basement; disconformably overlies Cainozoic sands and and worn foraminiferal species similar to those listed lavas, and disconformabiy underlies Lughrata Sand. On trom the Upper Quaternary ('1) fauna isolated from weathering it develops deep red-brown soils of the the coquina in the foredune S. of Trousers Point Ranga Association (Dimmock, 1957). Crable 5; D. J. Taylor, pers. comrn.). The dunes are The limestone is generally cream to buff, with cut by the late Quaternary 0.6-1.5 m. level (MHWS) fragments of mollusc shells, bryozoans, echinoid spines, and also app.ear planerl by the 4.5 m. level (MHWS), suggestll1g. WIth degree of consolidalion and calcareous holothurian remains, algal remains (including Lith 0. thamnium), poorly preserved foraminifera and quartz content, an age at least pre-late Riss/Wiirm. grains; secondary calcification is prominent and organic Liapota Sand remains may he almost completely replaced (Crespin, This siliceolls aeolian sand, at least 6 m. thick, is 1945a; Everard in Hughes. 1957; Ludbrook, 1965). typically exposed arollnd The Quoin and forms the Chemical analyses (Everard, loc. ciL) generally show chief soil type in the Liapota Association (Dimmock. 60-95% CaC03, with a mea n at 83 (It! • except at J 957). It disconformahly overlies Palana Limestone, is Parrys Bay-Blue Rocks area where more siliceous disconformably overlain by Lughrata Sand, and rocks average ahout 70% CaCOo• lnundates granite hills up to 180111. in elevation. Early workers considered the limestones to be marine It is white to grey sand passing down into darker deposits, but Dimmock (1957) considered them dune coloured strongly developed carbonaceous organic 'B' aeolianites. a view supported by the author's horizons, . suggesting a Pleistocene age. Geomorphol geomorphological studies Foraminifera in the lime ogIcal eVIdence suggests dunes associated with old stones (Table 5) have been dated as upper Pliocene Pleistocene shore lines, at least Riss/Wiirm in age. Pleistocene (Crespin, 1945a), Pleistocene (Lndbrook, Altmoor Sand 1965) and 'derived from the Tertiary' (D ..1. Taylor, This siliceous aeolian dune sand, at least 2.3 m. thick, pel's. comm.). The hitter forms were described from IS exposed at Ranga at elevations mm,tlv 30-60 m. Ranga as 'poorly preserved, badly worn and frag a bove sea-level. and forms the chief soil type in the mental foraminifera. bryozoa and mollusca. Foramini Altmoor Association (Dimmock, 1(57). It disconform feral determination was difficult at specific level, though ably overlies Palan

TABU' 6. QUATERNARY MOLLUSCA. LAGOONAL LIMESTONES, FLINDERS ISLAND

Lagoonal Limestone ! Holloway's Quarry Lmst. -,------~~------,--~---- .. - Molluscan ldentificarions N. of Red Bed Bed Bed R. W. T. Emita d c b a Wilkins Colltn. _._. -.------. i Assiminea tUSI1Wllic{{ (Tenison Womb) x .---. Coxiella sp. x _._----- Freshwater species A IIslropyrglls buccinoides (Quoy & Gaimard) x x x x Beddomena lodderae (Feltenl) x x x Glyptanisus atkinsoni (Johnston) x x x L G me;ridio/wlis (Brazier) x Lellumaria sp. x L. sp. (jl/l'el1iles~ x L. pyramidata (Sowerby) x x Revises,I'O/' turhinatlls (Petterd) x x x x S'il111imllca sp? x S. gunlli (petterd) x s neglecta (Petter d) x V alvatusma iasmallica (Ienison Woods)? x - Land Species Egilolllen barrellense (Petterd) x x Geminoropa sp.'? (juvenile) x p edicllmista caesa (Legrand) I x Thyrasonu diemel/ensis (Cox)? x

Jdentifi<:ations by R. C. Kershaw (Holloway's Quarry) and Ludbrook, 1965 (limestone, N, of Emita).

Similar Pleistocene lagoonal deposits may be rep Glacial. Where grits with cemented organic 'B' horizons resented by soft earthy Ii meslone N. of Lady Barron occur, as at Big River (Dimmock, loco cit.), these (Dim mock, 1957, p.27), from the Five Mile Lagoon proba bly represent older deposits. (Wingaroo) area (Everard, Joc. cil.) and from 0.4 Km. E. of Franklin Village jetty, Cape Barren Island UNDIFFERENTIATED QUATJ.i:RN ARY DEPOSrrS (1964:35:5: coIl. R. W, T. Wilkins). These include beds of waterworn grits, gravels, sands and clays, including stanniferous and organic enriched QUATERNARY AJ~LUVJAIJ DEPOSITS deposits in the Whitemark-Blue Rocks, Tanners Bay These are most prominent flanking highlands of Killiecrankie, Bootjack and Mem,lna areas (Dimmock, Palaeozoic basement rocks sllch as the Strzelecki and 1957; Jack, 1966). Pebbles and crystals of gem quality Darling massifs. topaz and associated minerals occur in such beds at Kil1iecrankie (Gould, 1872; Petterd, 1911). Some deposits Loccota Grit resemble Opossum Boat Harbour Grit and probably This siliceous grit and gritty clay, at least 1.5 m. thick represent alluvial accumulations reworked by Pleisto is exposed around Loccota in creeks draining into cene seas, Some angular quartL grits and clay resemble Fotheringate Bay and forms the chief part of the Loccola Grit, as in tbe While mark-Blue Rocks area, Loccota Soil Association (Dimmock, 1957). It overlies at the mouth of the Leventhorpe Creek and elsewhere. granite basement, and in part at least. appears to dis These arc probably allllVial deposits formed in areas conformably (7) overlie Palana Limestone. It contains exposed by withdrawal of the last Pleistocene Inter a high percentage of angular quartz grit and represents glacial or Interstadial sea or in areas unaffected by alluvial accumulations of granite detritus from Pleistocene marine transgression. Strzelecki Peaks. Part, (lr most, of the material was Old drainage deposits include an exposure in road probably derived and deposited during the Wiirm cnts on the Whitemark-Memana Road (grid 630N- 170 THE CAINOZOIC GEOLOGY OF FLINDERS ISLAND. BASS SIRAll

913E) of a bou!.der bed 70111. across and at least 2.4 m. PsclIdom.ys cL lJ()vaehollandiae, no longer live in South thick, ·fhi, occupies an c:lst·west irending stream profile ertstem Australia. The two topmost layers of the bone cut into underlying Mathinna Beds. The deposit con deposits in the cave floor gave Carbon 14 dates of sists mainly of rounded fragments of Mathinna Beds up 8,110±340 and 8,200±120 years B.P. respectively, to 23 em. across, but includes fragments of hornfels and and Hope suggests that the deposit may partly rep quartz aDd in places passes into a coarse sandy matrix. rcsent an old lair 'Of the Tasmanian Devil Sarcophilus Minor areas of siliceous dune ridges occur around harrisi. Bootjack, .Memana and Blue Rocks, and many of the A. sub·fossil bone deposit was exposed in a large well de\'eloped profiles in Soil Associations mapped sand blow in Lughrata Sand at Palana and included by Dimmock (1957) were developed during the Pleist remains of tachyglossids, dasynrids, peramelids, phalan· ocene. gerids, vombatids, macropods, murids, birds and lizards Recent deposits incllllle: CHope, 1969). Almost all the species represented in the (1) alluvial deposits of the present drainage, deposit are present on Flinders Island today, but lsodon (2) soils developing on late Quaternary dunes and oheslllus now exists .in Bass Strait only on West Sisters ridges, fsland and Sarcophifius /zarrisi is no\v extant only on (3) coastal barriers enclosing east coast lagoons, the Tasmanian mainland. Macropod and vombatid (4) beach accurnui:1tions including shell beds. bones were also exposed in sand blows at Killiecrankie (5) lagoonal peat deposits, and Trousers Point. (6) cave and clune bone deposits, Miscellaneous (7) miscellaneous deposits. Emu egg shell fragments were recovered near Emita, The fiTSt three types of deposit wi!! be discussed in 6.5 Km. inland at about 180 m. elevation (call. F. more detail when the geomorphological aspects of the Jackson, 1917; 1965:39:6). This appears to be the first authors' studies arc presented and only the others will record of the emu on the Furneaux group, but the be considered further here, distribution data of this bird makes it uncertain that Beach Shell Accumulations the Flinders Island fragments are truly local (Hope, These occur at a Ilumber of shore localities and 1969, p.232). include buried deposits. At Yellow Beach, Lady Barron, An Australite, found in an abandoned tin mine near digging into the sandy beach 0.3 m. below the high Killiecrankie Bay (Tasm. Mus. CoUn. Y132, pres. J. tide level exposes a packed shell bed 15·23 em. below Dunn, 1962) is lens shaped, 12x9x5 mm. in size (S.G. the surface and extending to at least 0.6 m. in depth. 2.45) and shows numerous fine ridges radiating from The fauna (Table 4) is identical to that of the present the centre of one surface. This presumably belongs to "hOfe here, and pieces of wood OCCllr amongst the the tektite shower over Aust.ralia dated stratigraphically shells at about 0.4 111, depth. This wood gave a radio as late Pleistocene or early Holocene, possibly between carbon dating of 3,970±90 years B.P., suggesting that 7,380+250 and 4,830+250 years B.P. (Gill, 1965). the deposit possibly formed by a sea refreating from However, recent K-Ar isotopic dating of AustraJites a Post-Glacial higher level (E. D. Gill, pers, comm.). (lV1cDougali and Lovering, 1969) indicates an age of Lagoonal Peat Deposits formation possibly as old as O.R6±0.06 m.y., with atmospheric flight shortly after. This enigma between Descriptions and approximate analysis and oil deter physical and stratigraphic dating still requires reconcili mination of materi

Volcanism ]965). This sediment. with material eroded from Volcanism. possibly commencing in the Lower or .Mid FI inders Isla nd over long periods, was probably trans Tertiary. appears related to tbe Tertiary fracturing and ported by ihe easterly currents 10 deposit on the eastern the basement structure, with rongh alignment of: centres coastal shelf as an abundant. siliceous source. from Badger Corner. Ranga, vVhitemark.Mi I.even The dune building was apparently a repeating pattern thorpe. Parrys Bay and Lughrata io Tanners Bay- of formation of coastal dunes during relative still-stands Palana areas. OJivine-nephelinites in t.bl' central in sea-level fluctuations, parabolic re-orientations of part of the Island and alkali \0 the dunes during stormy periods. and erosion and drowning north and south. sometimes peridotite and of dunes by marine transgressions during Interglacials country rock fragments. A Sarnphire and ] nt.erstadials. Orientations in the parabolic dune River overwhelmed swampy mclaleuca (here systems rellect the influence of the prevailing westerly producing silicijjed logs, and tuff at may winds, which have obviously operated over mllch of have exploded from aqueous eruption. the Quaternary and would be particularly severe as the westerly wind belts moved northwards during G.lacials. Marine Deposition East-west orientations predominate on the west facing Marine transgression on Flinders Island probably wok parabolic dune series of the west coast and inland, and place during early Miocene time, in accord wilh such also occur in east coast dune series. which however deposits on Tasmania, Victoria and Cape Barren show more marked E.N.E-IS.W.S. and N.W.N./S.E.S. Island (Ludbrook, 1967; Richards and Hopkins, 1969). orientations. with the record removed or obscured by later erosion The older dune series of the fsland became increasing or deposition. Regression of the Miocene high sea in ly consolidated with time and developed Inature soil Upper Miocene-Lower Pliocene time. from evidence profiles (Dimmock, 1957). Calcareous dunes, as now from Gippsland Basin and Bass Strait shores (Bowler, forming Palana Limestone. became subject to secondary 1963; Bock and Glenie. 1965; Taylor, 1966; Sutherland cemenlation with formation of calcareous 'B' soil and Corbett, 1967), presumabJy affected Flinders Island horizons. Leaching of top parts of dunes probahly gave and accords with fossils washing ashore from inferred 'A' horizons of siliceous residue which possibly blew off-shore Kalimnan beds and with derived Upper off exposing the underlying limestone and Illay have Miocene-Lower Pliocene foraminifera in the aeolian contrihuted in part to sand ridge deposits such as Palana Limestone. Liapota Sand and Altmoor Sand. Cave development Later Pliocene marine transgression on Flinders was probably initiated fairly early in the consolidation Island is indicated by the posf.·KaJimnan Cameron Inlet of the calcareous dunes, with some deVelopment of Formation at elevations above present sea.. JeveL These linear caves occupied by streams. {{apid erosion by suggest a shore line fringing the eastern and northern tbe streams resultecl in sink holes, gorges and stranded ,flanks of thie Dc,rling Range and extending north caves as found west of Ranga (older than 8,000 years through Wingaroo. Withdrawal of this sea by late B.P.). Tertiary time is indicated by erosion and deposition of Consolidated dunes with lower calcareous content Pliocene remanie, shells in overlying transgressive (west coast, e.g. TroLisers Point aeolianite) and typically Lower Pleistocene marine deposits of the Memana siliceous content (east coast, e.g. Petibe1a Sand) Formation. ~ developed during the Upper Pleistocene. Unconsolidated parabolic dunes (e.g. Lughrata Sand and Nala Sand QUATERNARV dunes) probably originated as beach ridges or foredunes Climatic changes related to the Pleistocene Glacial developing continuously from the Wiirm Glacial. The had important effects on Flinders Island. Conditions parabolic movements were probably initiated during became favourable for extensive dune building, and stormy conditions in the Wiirm, continuing into the sea-level fluctuations left their imprint through variations Post-Glacial period, and truncation of the parabolic in marine and terrestrial erosion and deposition giving ridges took place with establishment of a Post-Glacial stra,nded shorelines. cltrne movements and lagoonal shore line. A coastal beach ridge system (Laekrana developments. . Sand) developed. continuing through to the present and punctuated in places with minor parabolic move Dune Building ments. The evidence of thc barrier at Arthllf River, "t least, suggests a still-stand or a relative slowing Dune building on the west coast was predominantly down of the Post-G lacial sea-rise. before a rapid rise calcareous. Vast areas of Tertiary calcarenites :md to a 0.6-1.5 m. (MHWS) level flooding the barrier. marls were probabJy exposed on withdrawal of the possihly about the Post-Glacial Thermal Maximum initial Glacial sea. providing an abundant calcareous (Gill, 1955). "ource. Siliceous sediment may have been largely removed from tbe area by predominantly east flowing Lagoon .Formation currents in Bass Strait (typical of present winter flow, Vaux and Olsen, J 961), and siliceolls dUlles only Extensive lagoon development, particnlarly on the east formed in localised areas where rivers acted as siliceous coast. has been associated with dune formation on the ';Ollfces. Tn contrast. dune building on tbe east coast Island, following imponnding of drainage by coastal was predominantly siliceous. A contrihuting source of barriers and by parabolic movements. Traces of old siliceolls sediments appears to have been the straits lagoons formed during the Pleistocene and early bounding the Island acting in similar fashion to rivers. Holocene are found in inland areas and freshwater and predominant long term drifts operating along the limestones were deposited in some of these. Tasmanian coast also tend to concentrate siLiceous During the early Holocene, probably in a period of: sediment on the N.E. corner of Tasmania (Davies. increased rainfall, small lagoons impounded by para- 172 THE CArNOZOIC GEOLOGY OF FLINDERS ISLAND. BASS S"I.RAlT bolic dunes increased in size and coalesced io form Summaries of references to the known present fauna extensive lagoonal areas of Nelsun Lagoon type. Further of the Island are given by Green (l9fl9) and Hope lagoons formed meanwhile in swales of parabolic (1969) and presumably endemic species are known from dunes. Many of these became reduced in size, probably the Ranga cavc (Green, 1%3; Richards, 1967, 1970). during a period of reduced rainfall, and lunettes SUb-fossil remains of A epyprYlIltlus ru/escens, Pseu developed. With the building of the present beach domys cf. novllehollandiae, Sarcopizillls hurrisi and the ridge coastal barrier, apparently following establishment emu cn represent animals no longer living on the of the Post-Glacial sea, extensive coastal lagoons and Island. and Hupe (1969) discusses possible migration inlets have formed. Encroachment of the lunette at and isolation patterns of some vcrtebrate distributions Hogans Lagoon onto the oldest beach ridges suggests across Hass Strait. that lunette formation and the associated climatic Of interest here is the Tasmanian Ahorigine, an period were probably latcr than the Post-Glacial <;ea isolated Tace when discovercd by Ellropeans and OCCll rise. pants of Tasmania at leas! 9,000 years ago. Mainland Marine Fluctuations Australian excavations yield similar stolle implements Sea-level fluctuations associated mainly with Pleistocene in lower levels to Tasmanian types, suggesting a main Glacial fluctuations have left traces of old shore lines land origin for the race and llse of the Fmneaux chain on Flinders Island. Erosional and/or depositional as a land bridge, probably between J 6,000 and 1 j ,000 features have been observed associated with old shore years ago (Jones. 1968). Some possible cvidencc of lines at 57-72 m., 27-33 m., 15-1 R m., 4.5-6 m. and prehistoric Aboriginal occupation of Flinders Island is O.fl-l.S m. above MHWS. Erosional features are rep very meagre CW. F. Ellis, pers. comm.). Rare Aboriginal resented by benches Cllt in granite, dune limestones and artefacts from Cape Burren Island include some flaked other sediments, in places forming extensive coastal stone atypical of the Island and possibly transported flats. and in the case of the 0.6-1.5 m. level by trun by visitor (Rhys Jones and R. A. Littlewood, coIln.). cation of parabolic dune series. Depositional features However, coastal Aboriginal camps on the old Furneaux include the Memana Formation (a shallow waier marine landbridge would be now submerged under Bass Strait horizon occupying a Lower Pleistocene embayment in (Jones, 1968). the North Patriarch area), Marshall Bay Coquina At present, the Flinders Island area experiences (probably a beach deposit associated with the 15 m. occasional earth tremors, being one of the seismically level), East River Coquina (bay floor and sea-channel strongest regions of the generally quiet Tasmanian deposits, some with remanie material derived from block. A swarm of tremors in N.K Tasmania in underlying horizons by penecontemporaneous erosion, 18R3-1886 probably originated from off-shore epicentres probably related to the 4.5 m. level) and Petrification (Shortt. 1885. J 886; Biggs, 1 88fl). Epicentres plotted Hay Coquina (a shallow bay deposit associated with since 1929 (magnitude, m4.0-5.7) fall across the middle the 0.6 m. level). Angular grits and associated sediments of the Island and may be related !o cross-structures (e.g. Loccota Grit) probably represent detrital accumu on a westerly striking seismic zone extending through ulations resulting from heightened erosion associated the Island across Bass Strait from Longitude 156 0 to with marine withdrawals, as in the Wiirm. Well worn 144' (Doyle, Everingham and Sutton, 1968). grits (e.g. Opossum Boat Harbour Grit) probably rep resent extensive reworking of snch deposits during ACKNOWLEDGMENTS marine advances, as in the Riss/Wiirm Interglacial. The following h,lYe encouraged, critically read, advised The 0.6- 1.5 m. level includes a Post-Glacial level and and assisted the authors' work to a c'Onsiderable degree: possibly some late Pleistocene levels. as dated elsewhere E. D. Gill and T. A. Darragh (National Museum of (Gill, 1970). Dating at Lady Barron beach suggests Victoria, Melbourne);M. R. Banks, J. L Davies, R. that the sea was near this level at least 4,000 y,:ars Varne. D. Duncan, C. Gee ,md P. G. Quilty (Uni ago. The 4.5 m. and 15 m. levels can probably be versity of Tasmania); G. M. Dimmock (C.S.I.R.O., assigned to the Riss/WUrm, but higher levels are Division of Soils); D. J. Taylor and A. C. Collins probably pre-Riss/Wiirm and the 57-72 111. level may (Melbourne): A. Baker (UniVersity of Melbourne); J. even represent the Mid-Miocene high sea. Many W. Warren and N. A. Wakefield (Monash University): aspects of dune building and evidence of sea-level D. J. Jennings and D. I. Groves (Tasmanian Mines fluctuations from the Upper Cainozoic on Flinders Department); R. M. Warneke (Fisheries and Wild Life Island parallel deVelopmental histories of the Bass Department, Victoria); F. Brown (Mt Pleasant Strail region on King Island (Jennings, J959b), the Laboratories, Lallllceston); T. Scott (formerly South Tasmanian north coast (Edwards, 1941: Sutherland, Australian Museum); J. H. Hope, D. H. Green and 1971: Gill. J 970) and the Victorian coast (.lennings. E. Kiss (Australian National University); W. P. Ellis and Mabult, 19f17; Jenkin. j908l. ~ (Queen Victoria Museum. Launceston); andW. Bryden. E. H. Turner and A. J. Dartnall (Tasmanian Museum. Hobart). J. U. Svmons (Director, Tasmanian Mines Faunal Fluctuations Department and cr. A. Barnes (Director, South Aust Sea-level and associated climatic fluctuations on Flinders ralian Mines Department) provided copies and gave Island during the Cainozoic would influence terrestrial permission to use unpublished geological mapping and faunal movements and at times isolate popltJations. The reports, while R. W. T. Wilkins, C. Stirling, E. Docker, Islancl undoubtedly formed part of Jand bridges that F. Henwood, A. Dart, C. Brown, J. Robinson. 1. M. connected Tasmania and the Allstralian mainland Fowler, F. R. Rhodes and many residents assisted with during Pleistocene Glacial marine withdrawals, when local knowledge of Flinders Island. Martom (manage sea-level along Australian shores 111ay have fallen ment) Ltd and Crystal VaJley Mining Co. Ltd assisted 135 m. and possibly as much as 180-210 111. in depth with data from rece11l preliminary exploratory investi (Packham. ct. al. J 9fi9: Gill. J 970; Jongsma. 1970). gations. F, L SlrrHERLAND AND R, C. KERSHAW 173

APPENDIX I Petrological Descriptions, I?!inders Island Cainozoic Tanners Bay-Boat Harbour-l'alana Cr.S, 1142, 1296- Volcanic Rocks 1298, 1341, 1343), T.S, numbers refer to catalogued tbin sections in the Glomeroporphyritic corroded olivine (5-20'/(J, 3 mm. max" 2V,~,90-98°) is contained in an inlergranular to Tasmanian Museum collection, pilolaxiti~ groundmass of: plagioclase lath, (35-50%, Samphire River-Adelaide Bay-Chew Tobacco Creek 0.4 rtlm, max" zoned from about Ab 44-50), pinkish (T.S, 1338, 1342, J 344, 1482), augite (20%, 0,3 mm. max.,), squarish iron oxide grains Corroded glomeroporphyritic olivine (10-15 %, ::; mm, \5-1 , 0,2 mm, max,,), granular olivine, apatite needles max" 2V ,--,93-9)D±3°) is set in an intergranlllar and zoned sodic plagioclase, Amygdales may z contain greenish to yellowish collofonn op,iI, radiating grollndmass of plagioclase laths (35-45%, 1.4 mm. max" calcite or [erroan carhonate, Some rocks contain rare mostly < 0.5 mm" zoned from about Ab 44,,50), pale microphenocrysls of titaniferolls augite (1 111m, max" pinkish augite (30-35 '1(), 0.4 mm. max" avo 0,1 mm,) sometimes with corroded riddled cores) and aggregates olivine (5%) and opaque iron oxide (5%, iitano-mag of prismatic clinopyroxene, sometimes in reaction netite or ilmenite), minor apatite and interstitial zoned coronas aronnd fused or partially fused quartz and sodie pl8gioclase. In dense samples the olivine is largely rare feldspar xenocrysts, unaltered, iron oxides tend to form sqnarish grains, Parrys nay (T.S, 1300, 1340, 1485-14:0,8), and interstitial patches of carbonate (up to 10%) and Corroded olivine phenocrysts and rarer xenocrysts serpentinitic material may be prominent. In more (l0-20%, 3 mm. max" 2V, C"-'88-1(00) grade into a amygdaloidal varieties olivine is rimmed by green opaJ groundmass of titanaugite "<30-50'X" 0,6 mm, max,), or is largely altered to serpentine, 'bowlingite' and squarish 1.0 irregular iron oxide grains (7%, mostly carbonate, iron oxide tends to form elongate blades, < 0.2 mill.) and coarse to needle-like apatite prisms and amygdaloidal fillings include calcite, ferro an car (3 %, 0,6 mm. max,), with a poikilitic or hyalopilitic bonate. clay, opal and chalcedony. Rare accidental mesotas!s 00-30%) containing variable proportions of quartz and quartz aggregate inclusions show thin idiomorphic to allotriomorphic potassic nepheline reaction coronas of clinopyroxene needles, (0,6 mm. max.), colourless to brownish glass, some alkali feldspar, and interstitial and mnygdaloidal zeo N. Ranga-E. Whitemark (T.S. 1139, 1141; Analysis 1. lites, including stilb.ite, natrolite and analcime, Table 2). N. hlghrata ('I.S, ]301, 1345, 1592, Analysis 2, Table Glomerophenocrysts of corroded olivine (l(1-15%, 2). 1.4 mm. max., 2Vzr-'95-1(00) and euhedral oscillatory Corroded olivine phenocrysts and peridotitic xenocrysts zoned titaniferous augite (5-10%, 1.5 mm. max., and xenoliths form 35% of the rock, in a fine grained 2V7,r-'62-48° ± 2°) are heJd in subophitic to intergran gronndmass of augite (mostly < 0.2 111m,), granular ular and poikilitic groundmass of plagioclase Jaths olivine, squarish iron oxide grains and apatite needles (20-30%, 0.9 mm. max" zoned from about Ab 44-50), in a feldspathoidal base (20%) containing potassic titaniferous augite (20-30%, mostly 0,05-2 mm.). nepheline, colourless glass and zeolites (including sporadic iron oxide (to 0.7 mm,), apatite and rare analcime and natrolite) in patches up to 0.3 mm. olivine, with interstitial zoned sodic plagioclase (to across, 15%), minor colourless glass dusted with iron oxide The peridotitic xenoliths (mostly < 2 em,) consist pre and amygdaJoidal carbonate. dom inantly of olivine, associated withh orthopyroxene, clinopyroxene and spinel in allotriomorphic consertal Wbitemark (Palagonite Tulf; Petrological Records, to granular inclusion textures. Xenocrysts (mostly < 4 Tasm. Mines Sel'. No. 58-23), mm,) derived from these xenoliths are commonly dis 'Dark coloured rock composed of black porous frag tinguished by exsolution, resorption and strain phenom ments cemented together by carbonate of lime. ena and by reaction coronas and overgrowths of the In thin sections the black fragments appear as a host groundmass minerals, Magnesian olivine (2V7,r-' brown glass and a green zeolite, The glass contains 8R-97°; MgO 46,6. FeO 1 L 1) may sbow strain polar many pores some of which are Illlee[ with zeolitc isation and translation lamellae; aluminolls enstatite spherulites and others with calcite. Some fragments (2V zc"-'76-84"; SiO, 53.4, MgO 33,7, 'FeO' 5,S, ALO" consist entirely of masses of zeolite spherulites, The 5,0) may show lamellar or granu!:lr exsolution of clino refractive index of the glass varies, being in some pyroxene, spongy resorption or symplectic resorption parts lower than Canada balsam, ill others, higher. intergrowths, and overgrowths of augite or coronas of Plagioclase and olivine occur as relic minerals from olivine and iron oxide; sodic aluminous endiopside the original glass', (2Vz.~70-66°; SiO, 51.7, CaO 19,3, MgO 16.5, ALO., E. Leventhorpe (T,S. 1483-1484) 7,7, 'FeO' ],0, Na,O 2,2) may show corrosion riddling Corroded olivine phenocrysts and grains (J 5-20%, and overgrowths of zoned groundmass augite (2V7,r-' 2.5 111m, max" 2V zr-'93-1 00°) are dispersed in an inter 53-41 "; SiO, 49,8, CaO 23.3, MgO 14.3, 'FeO' 7,4, granular to poikilitic grollndmass of plagioclase laths ALO" 4,9, '1'iO, 1.7) becoming coloured and titaniferous (35-40%, 0,8 rnm, max., zoned from abont Ab 44-50), towards the rims; and olive' to reddish brown chrome colourless augite (30%, 0.4 mm, max,), sporadic iron ('I) spinel (ALO, 54.3, MgO 21.1, 'FeO' 10,3) may oxide (to 0,5 mm.), minor serpentinite and chlorite, show opaque reaction rims of chrome (1) iron oxide small apatite needles, and interstitial and amygdaloidal (preliminary electron microprobe analyses, oxide per zeolite (5-10%, mainly phillipsite?), centages, per R. Varnc), 174 THE CAJNOZOlC Gl'OLOGY OF FLll'iDERS ISLAN]), HASS SfRAIT

REFERENCES GrLL. E. D.. 1962: Past and Present Dj,tribntion in Australill of the Gastropod Tylospira. ], Malac, BIGGS, A, B., 18k6: Tasmanian Earth Tremors, Proc, Soc. Aust. ll: 33-7. Ro.),. SoC, 1'0.\'111. for 18ii5: 325-34, GILL. E. D., 1964: Rocks contiguous with the Basaltic BLAKE, F., J 935: Preliminary Report Oil. Furneaux Cuirass of Western Australia. Pmc. Rov. Soc. Group of Islands, Unpuhl, Ref', Del'. !vfill(?s Tilsm, Viet. 77: 33155. . BLAKE, F" 1947: The Flirneaux Group of Islands. GH.L, E. D" 1965: Radio-Carbon Dating of Australite Unpu/>Z, Rep, Dep, Mines Tasm. (1947): 52-82. Occllrrences, Microliths. Fossil Grasstrell and BOCK, p, E" and GLEcNIE, R, C" 1965; Late Cretaceous tIllman Pocisol Structures. Ails!. J. Sci. 27: 3OtJ· L and Tertiary Depositional Cycle, in South-Western GILL E. D., 1970: Current Quaternary Shoreline Re Victoria, Prot.;, Roy. '<;0<:. ViCI., 79: J 53-63. search in AlIStralasia, A list. 1. Sci. 32: 426-30. BOWLER, 1. M" 1963: Tertiary Stratigraphy and Sedi GILL, E. D. and BANKS, M. R., 1956: Cainozoic mentation in the Geelong-Nfaude area, Victoria. History of Mowbray Swamp and Other Areas of Proc, Roy. Soc, Viet, 76: 69-137, Nonh·\Vestcrn Tasmania. Rec. Q. Viet. Mils. 6. CANE, R, p" 1966: 'Oil' on Flimlcfs Island-Bass Strait. GOULD, C., lx72: Tbe Islands in Ba.ss Straits, Proc, Prut', Roy. HIO: .153-5, Soc. Tilsm. Roy, Soc. TaslIl, for 1871: 57-67. CAREY, S, W" 1945: Interim report on the possihility GHEEN, A, J, A., 1963: A New Species of Echinodillo of petroleum on J,'linders Island, Unpubl. Rep, (lsopoda, Oniscoidea, Armadillidae) from Flinders DCJl. Mines Tasl1l, (1945): 153-5, Island, Tasmania. Pmc. Roy, SoC, Tast/l, 97, pp, CAREY, S. W" 1953: The Geological Structure of Tas 77-80. mania in relation to Mineralisation, 51h Em)), GREEN, R. H" ]969: The Birds of Flinders Island. Rec, Min. Met. COI/Rr, 1: 1108-1128, Q. Viet, Mus, 34, CHAPMAN, E, and PRITCHARD, G, B., 1904: Fossil HAIU

KElD, H. W. G., 1949: Mineral Deposits of Flinders and RlCHARDS, K. A .. and HOPKINS, n. M., 1969: Explor Cape Barren Islands. UIl[lubl< ReP< Dep. Mill. TaslIL ation in the Gippsland, Bass and Otway Basins. E.C.A.F.E.. Canberra. KERSHAW, R< C, 1958: Tasmanian fnterlidal Mollusca< 1. Malae< Soc Aust. 1: 2: 58-JOO. SCOTT, H.H., 1915: Some Notes on the Humeri of Wombats, Q. Viet. Mus. Brodt. 5. KERSHAW, R< C, and SUTHERLAND, F< L, in press: Quaternary Geomorphology of Flinders Island, Bass SCOTT, H. H., and Lorm, C. E., 1922. The Cave Dc Strait.. Rec. Q< Vict. Mils. posits at Mole Creek.. i'roG. Ro\,. Soc. Tasin. for 1921. (i,S. LUDBROOK, N. H., 1965: Palaeontological Reports and Accompanying Notes on Samples F33/65 and SHORTT, .I., J 885: Summary of Observations on Earth· F34/65 from Flinders Island, Tasmania. Type· quake Phenomena made in Tasmania during 1883 and 1884. 1')'oc. Roy. SoC, Tasm. [or 1884: 263-70. written Report 1094/64. Dep. Min. SOllth Aus!. SHORTT, J., 1886: Earthquake Phenomena in Tasmania. LUDBROOK, N. H., 1967: Correlation of Tertiary Rocks Ibid for 1885: 400-02. of the Auslralasian Region. From Tertiary Corre lations and Climatic Changes in the Pacific< Feb SINGl.ETON. F. A., and WOODS, N. 11., 1934: On the ruary, .1 967. Occurrence of tbe Pelecypod Genus Millha in the Australian Tertiary. 1'mc. Roy. So.c.Vict. 46: 207. LUDBROOK, N. H., 1969: The Genus Miltha (Mollusca, Bivalval in the Australian Cainoz'Oic. Trans. R. SINGLETON, O. P., and JOYCE, E. B., J969: Cainozoic Soc. S. Allst. 93: 55-63. Volcanicity in Victoria. S·pec. PubIs. GeoL .Soc. Ausi. 2: 145-54. McDOUGALL, I., and LEGGO, P. J., 1965: Isotopic Age Determinations on Granite Rocks from Tasmania. SPRY, A. R, and BANKS, M. R., (Ed.), 1962: 'The 1. Geol. Soc. Aust. 12: 295-332. Geology of Tasmania: J. Ocol. Soc. Aus!. 9, 2. McDOUGALL, L, and LOVERING, J. F., 1969: Apparent STRZELECKi, Count P. E., ] 845: Physical Description 'Of K-Ar dates on cores and excess Ar in flanges 'Of New South Waks and Van Diemert's Land, L, B, Australites. Geochim-Cosllwchim-A eta. 33: 1057·70. G & I.. London. MARWICK, .T., 1960: A New Pliocene Struthiolaria SUTHERLAND. F. L., 1969: A Review of the Tasmanian (Gastropoda) from Flinders Island, -1'aSI113n1a< Proc. CainoZ'c;ic Volcanic Province. Spc·c. PubIs. Geo!. Soc. Aust. 2: J 33-44< Roy. 5'"oc. Vict. 72: 41-4. SOTHERLAND, F.L., 1971: The Geology and Petrology MAY, W. L., 1958: An Illustrated Index of Tasmanian of the Tertiarv Volcanic Rocks of the Tamar Shells (revised by J. Hope Macpherson). Tasm. Trough, Northern Tasmania. ReG. Q. Viet. Mus., Gov'! Printer. 36. NYE, P. B., ]931: Underground Water at 'Wingaroo', 5 SUTHERl.AND, F. L, and CORBETT, K. D., 1967: The Mile Lagoon District, Flinders Island. Unpubl. Rep. Tertiary Volcanic .Rocks 'Of Far North·West Tas Dep. Mines Tasm. mania. ProG. Roy. Soc. Tasm. 101: 71-90. NYE, P. B., 1969: Some Occurrences of Peat or Semi.. TASMANIAN DEPARTMENT OF MINES, 1970: Catalogue of peal in Tasmania. Tech< Rep. Dep ..Min. Tasm. 13: tbe Minerals of Tasmania. Geol. SUl'v. Rec. 9. 34-6. TAYLOR, D. J., 1966: Esso Gippsland Shelf N'-I; The PACKHAM, G. H. (ed.), 1969: The Geology of New Mid-Tertiary Foraminiferal Sequence. Appendix South Wales. f. GeoJ. Soc. Aust. 16, l. 2. Bur.. Min. Res. Grol. Gcophys. A list. Petroleum PETTERD, W. F., 19 J 1: The Minerals of Tasmania. Proc. Search Subs. Acts Publ. 76. Roy. Soc. Tasm. fOf 1910: 1-222. TURNER, E.. 1970: A Systematic List 'Of Molluscs Dredged by the Japanese Research Ship Vmi/aka PRYOR, R. J., 1967: Soil Type and Land Use, Flinders Maru in Januarv. 1968. Tusin. Fisheries Research. Island. Proc. Roy. Soc. TasfII. 101: 261-6. 4,2: 1-18. . QOILTY, P. G., 1965: The Age of Tasmanian Marine VAUX. D., and OLSEN, A. M., 1961: The Use of Drift Tertiary Rocks. A ust. 1. Sci. 29: 143-4. Bottles in Fisheries Re!iearch. A list. Fisheries Nmvs- RICHARDS, A. 0., 1967: The Raphidophoridae (Ortho 1<'1tC1. 20: ]7-20. ptera) of Australia, Part 5. The Raphidophoridae WILKINS, R. W. T., 1962a: In Cainozoic Marine Suc of Flinders Island. Proc. Linn. Soc. N.S.W. 92, 3: cession in 'The Geology of Tasmania'. f. Geol. 273-8. Soc. A list. 9, 2:235. RICHARDS, A. 0., 1970: Ibid. Part 8. Two new species of WILKINS, R. W. 1'., 1962b: Miltha in the South,Eastern Parvolcttix Richards. Padf. 1ns. 12, 1: 1-8. Australian Tertiary. I. Malac. Soc. A list. 6: 43-9. ADDFNDUM Silicified plant material recently recovered from low tide level at Petrifaction Bay crasl11_ Mus. Colln. Z1591, pers. Mrs A. W. McPhie and Mr R. Hewer) contains cones, twigs and needles, probably of casuarina (Dr .1. A. T'Ownrow, pel's. comm.). It is presumably sub-basaltic in origin which suggests an age probably not exceeding early Pliocene for the basalt there. If the supposition is held that the basalt blocked the !Jost-Kalimnan/ pre-Maretimo marine transgression lhen this would imply a Lower Pliocene (Kalimnan) age for tbis eruption.

PLATE 10 Fig. 1. -Pliocene coquinoid limestonc (Cameron Tnlet Formation), exposed in quarry, foot of The Dutchman (type localily of Wilkins 1962 Dutchman Coquina), looking North, 1957 photograph. Fig, 2. ---Nelson Lagoon Drain section. ! mile N. of East River. 100king north. 1957 photograph. Pliocene shelly marl of drain) and shelly sands of the Cameron Inlet Formation are disconformably ovcrlain by Upper Pleistocene East River Coquina containing numerous remanie Cuc'/J,l!o.,ea at its base. Fig. 3-Lower Pleistocene ('1) coquinoid calcrete (Mcmana Formation), from outcrop E. end N° 11 Road, Furneaux :Estatc. Fig. 4.-Cliff of Opossum Boat Harbour Grit (Upper Pleistocene'?), type locality. Note erosion at cliff base, just above H WM and also at bigher level below cliff top, Fig, 5.~Aeollanite (younger Palana Limestone memher), S. of Truusers Point. looking north. The aeoIianlte shows marked aeolian bedding, rests on granite and its upper surface is coincident with the 4.5 m. level above MHWS. Fig. 6.~" Type locality of Petrification Bay Coquina (Holocene',), wbkh forms the terrace level iust above high tiele mark. looking no)'tb·east. Nole basalt boulders all ~hore, F,P, 176 Plate 2. --Dorsal ·view, skul! of new Piiocene whale, ZI:nhiu;3 sp. drain excavation, Jvlemuna Flinders Island (Pho\ograph, per J. W. Warren). The scale is graduated in ~m,.