BUREAU OF MINERAL RESOURCES GEOLOGY AND GEOPHYSICS

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1 BMR PUBLICATIONS COMPAcruS tnon-lendjng--secilon) COMMONWEALTH OF AUSTRAlIA DEPARTMENT OF NATIONAL DEVELOPMENT BUREAU OF MINERAL RESOURCES GEOLOGY AND GEOPHYSICS RECORDS: 1950/4 MTCROPALAEON'rOLOGICAL EXAI:iINATION OF ROCK SAMPLES FROM THE Lo\!TER METILYA AREA, NORTH WEST BASIN, WESTERN AUSTRAL~A, COLLECTED BY DR. TEICHERT &. G. THOJ:,'IAS o fir '" by I. CRESPIN. j \~ 1 The information contained in this report has been obtained by the Department of National Development, as part of the policy of the Commonwealth Government, to assist in the exploration and development of mineral resources. It may not be published in any form or used in a company prospectus without the permission in writing of the Director, Bureau of Mineral Resources, Geology and Geophysics.

2 BMR PUBlJCATIONS COMPA.CTU~!NON-LENDiN~C~lI.O.N) l5lw/1 - ',' MICROPALAEONTOLOGICAL EXAIViINATION OF ROCK SAMPLES FROM.:.~.\ , "".., THE LOWER MIIDLYA AREA, NORTH-WEST BASIN.!.. ~ERN AUS.:±Mg& CO~...Q!ID2 BY DR. TEIC~ AND G. THQMA. '.J:.21!9 Re2.Q!.d No.!h. -I.. No. 83. Anticlill west of Minilya Homestead No. 85. No. 87. Hard, cream,- foraminiferal limestone. Foraminifera: Ammobaculites sp. Austrotrillioa howchini ~losculinella bontaggensis ~rginopora vertebrali Planorbulina mediterranensis Sorites margi~lis - Numerous miliolida.e Anticline on East side of Salt Lake. West of Mi'nilya - Homestead. Hard, cream, foraminiferal limestone, wi th foraminifera not so well preserved as in No. 83. F'orami nifera: (a.) Austrotrillinahowchini Clavulina difformis Elphidi'Um cf. adelaidru.!..is Flosculinella bontangensis ~eneroplis pl~~tus ~tes marginalis Valvrulina fusca Numerous miliolidae ~~radbado? Bore, Miniba Station. Limonitic grit with numerous foraminifera (Globigerin~ and Globotrunca~' very common). ~~inifer~:." Allomorp~ sp. nov. (cf. yelascoe~) Ammodiscus cretaceus AnomaiIna rubigihosa Anomalina sp. nov. Arenobulimina obesa Arenobulimina-obeSa BQIivinopsis_clotho (Form A and B) Bulimina proli~ Dorothla bulletta Dorothia cf. canula ~alina~~planata Dentalina catenula ~~in~ cf. gracilis Dentalina.L6rneiana Dentalina cf. ~gapolitana Dent~lin cf. Q~~ Eponides sp. nov. Frondicularla goldfussi Frondicularia mucronate

3 2 (b) Frondicul,e.ria ver,neuilb.qa, Frondicul'aria sp. nov. \ Frondicule.ria sp. Globig!!t!.na cretacea Globigerinella voluta Globotruncana canaliculata Globot~~uQane. me.rginat~ Glomo~~~roides var. Qrona Guembelina globulosa Guttulina R~~lzowi Gyroidi ne..girardana Glroidi~itida Haplophragmoid~ cf. glabra HaRQlRhragmoi~ sp. Lagena apiculata Lagena as'q.~!!agenahispida Lenticulina discnpans,lenticulina diademat~ Lenticulina munste i Lenticulina macrodiscus Lenticulina stephensoni Lenticulina subalata Lenticuli na williamsoni, Lenticulin~ spp. Marginulina cr~tacea Marginulina cf. jarvisi Marginulina cf. texasen~is Mar gi nq!i.!:! : s p. Marss~lla oxycona Nodosaria affinis Nodosarra-aspera Nodos~ cf. longiscata Parrella sp. nov. Palmgla r ugq.~ Planulina cf. taylorensis Planularia sp. nov. Pseudoglandulina manifes~ Sara.cenaria italica ~acenaria cf. ~~togana Sarac~ria trengularis Stensioiana sp. nov. SRiroplectammina dentata SRiroplectan~ sp. Vaginulina sut~is Y~euilina-2~ Dark grey siltstone with fragments of carbonaceous material gypsum, foraminifera and radiolaria. f,.oraminifera: Anomalina rubiginosa 'Anomalina sp. Bolivinopsis~lotho BolivinoRsis,sp. Dentalina cf. lorneiana norothi~-sp. -- Epis tomi na s p. Eponides sp. GaudrYin~ cf. painoi9&. Globiget!Ea cretacea Glob igerina vo~

4 3 Globigerina. sp. Globotruncana nanalicula~ Globotruncana cretacea GlOb'O"rOt"arra---sp.-- Gyroidina girardana Guembelina globulo~ HaploQhragmoides sp. nov. " Haplophr.gmoides sp. Lenticulina c~. alexanderi LenticulIn8 articulata Lenticuline ~ligostegia' Lenticuline secans Lenticulini stephensoni Lenticuli6a cf. rotulata LenticurIOe williamsoni Le'ilticuliill! sp. Marssonell~oxycona Parrel~ sp. nov. Planularia cretacea spiroplectamm1~ cushmani Stensioina sp. nov. Verneuffina --p'ar:r,i. Astroph~ sp. Cenosphae~ sp. 1 Cenosphaera sp. 2 (cf. C. imma~) ~yomi tr,a aus tralis DictYomitra multi costata Dictyomitra tr~ng laris Lithocampe fusiformis Porodis2.Q. sp. SQongod~~~ cf. expansus Spongoprunum sp. Apongotripus (Spongotri2,Qdum) sp. Stylosphaera sp.. Stylotrochus s p. TheocaQsa(TheocaQsomma) sp. " (c), Friable sandstone with abundant foraminifera (Globigerinidae rare) and Inoceramus prisms. Foraminifer~ PlanU'ITna-s p. nov: Ammddiscps cretac~ Anomalina rubiginosa Anomalina sp. nov. Arenobulimina preslei BolivinOQsis c~qtbo Dentalina sp.. Dorothia cf. bulletta Ellipsog! nduli~ sp. nov. Eponides s~. nov. Frondicularia cf. cordata Frondicularia fran~-- Frondicularia verneuil!9~ Frondicularia sp. Gau~ina laevigat~ I Globorotalia micheliniana Globotruncana canaliculata' "Q.l.Q.Q~runcana marginat~nyroidi ne. girardana Lagena aplcu~~ Lagena aspera Lenticulina diademata Lenticulina:macrodi~~

5 4 No. 88. N.o. 89. No. 90. No. 91 ~i1 ulin~ cf. pondi Lenticulina stephensonl Lenticul~subal~ Lenticulina williamsoni Lenticul1ng sp. nov.-~ Lenticul~ sp. hov. 2 -Mar&!!illlina cf.q.~acea Marginul!.na cf. jarvi.l Marginul~ cf. ~xasen~ Marssonella cf. indentata ~sonerra 0eyoona P~lmul!a rugo~ Parrella sp. nov. 1. -Parrella sp. nov. 2. PIa'nularia sp. nov'. llinulina sp. nov. Saracenaria italica Spiroplectammina laev~ var. cretosa Vagi nuli na smuralis - Verneuili na parri ~neuilina triguet~ Approximately 1 mile W. s. w. of Neemerabadoo BQl!~ Cream, chalky limestone with small foraminifera. FQrami nifera:.ori tes margin~ Numerous small miliolio.ae Approximately -7/8 mile south of Nee~abadOQ Bore Shale w'i th abundant gypsum and a few forami nifera.-. Foraminifera: Ammod,iscus cretaceus Dorothia-bUIIetta 1 mile south of Neemerabadoo Bore Cream limestone.with foraminifera and bryozoa Foraminifera: Discorbis...Qycloclypeus Marginopora vertebralis.g,ite...illarginali.. 1 1/8 mile south ofn~rabadoo_~ Cream, foraminifera limestone. Plante_e: Li thothamnium._lamosissimum Forami nifera: Austrotrillina howchini Flosculinella bontangen2ig Marginopora vertebralis Planorbulina mediterranensis Qti]es margina~ Valu~ina davidiana Numerous miliolidae

6 5. No. 95. East Limb-2fAnticline, 3/~ mile E.~~~rabadoo J2Qre!,. Cream, foraminiferal limestone, with fragments of molluscan shells.. Plant~: Lithothamnium ramosissimum \. F'o~aminife~: 'Flosculinella~ntangensis Marginopora vertebralis Planorbulina mediterranensis Soritesmar-g!--ngl!~, Numerous miliolidae S,tratigraphic Notes " The samples from the Lower Minilya River area, North West Basin, consist of limestones, gypseous shale, limoni tic gri t and friable siltstone. The ages represented are Upper Middle Miocene Upper Cretaceous and Lower Cr~taceous. Upper Middle Miocene Nos. 83, 85, 88, 91 and 95 all of which are limestones, are referred to this age. Typical zonal forms such as Austrotrillina bowchini and Flosculinellabontangenili are present in many of the samples. Neither of these forms were found in No. 88, which is a chalky limestone but the general lithology and assemblage 9f smaller foraminiferalf orms suggest that it should be included in this group. The lithology shown in thin section and foraminiferal content of these limestones, is widespread in the Northwest Basin.. Cretaceous Samples 87 and 89 are Cretaceous in age. No. 87 is represented by three samples, from the Neemerabadoo Bbre. No., 89 was taken from an outcrop near the latter bore. The three samples from the Neemerabadoo Bore, which is about 1,000 feet deep, are of different Ii thology. Samples (a) and (c) which are regarded as representing the upper part of the bore section, consist of limoni tic grit and friable sandstone: respectively and contain numerous well preserved foraminifera of Upper Cretaceous age and in which Globotruncana canaliculata is common. A detailed study of the Upper Cretaceous microfaunas of the North-West Basin is now in progress but at present this assemblage from the Neemerabadoo Bore wi th the abundance of Globotruncana and the absence of certain species found in other sampres-in the area, suggest i~s correlation with Condonts samples Nos. 30 and 31 from the West Limb of the Giralia Anticline, North of Remarkable Hill (reported on ).., The lower sample (b) is regarded as'lower Cretaceous in age. It is represented by a dark, grey sil tstone in which numerous well 'preserved radiolaria are present as well as a few tests of Lower Cretaceous foraminifera. Also associated are some species of Upper Cretaceous foraminifera, but this is no~ unexpected as the samples were collected from the surface near the bore head.

7 6 T.his radiolaria-beari ng siltstone was found in outcrop by Dr. Ftsher (reported on 21/6/49) on the East bank of a tributary Of CardabiaCreek, 2 miles E.S.E. of "Photo Butte". Condon also found it in outcrop on the west limb of the Giralia Anticline, North of Remarkable Hill. No. 89 {s a gypseous shale containing two species of foraminifera both of which occur in the Upper Cretaceous sample from 'the Neemerabadoo Bore. (1. Crespin.) Cbmmonw~lth Pa1aeonto10gist. Q!!nberra. A. Cu. 17th February, 1950.,.