Palzontology. - Upper Cretaceous Smaller Foraminifera from Buton (D. E. J.). By F. G. KEI]ZER. (Communicated by Prof. L. RUTTEN.) (Comrnunicated at the meeting of October 27, 1945.) During the study oE the miàofauna of asphalt-bearing tertiary marls hom the island of Buton (SE of Celebes in the Duch East Indies) reworked upper cretaceous· smaller foraminifera were found in one of the samples. Generally these are almost pure Globigerina-Globorotalia-marls with the faunal assemblage very common in the Neogene of the Indopacific region. One sample, however, contains many sharply angular white and grey pieces of Iimestone and grey and black pieces of chert. resembling in alle respects, macroscopically as weil as. in thin-section , the cretaceous Globotruncana-Iimestones Erom the island present in the collection of the Geological Institute at Utrecht. In this sample many upper cretaceous smaller foraminifera are mixed with the tertiary assemblage. The cretaceous forms differ markedly from the beautifully preserved tertiary foraminifera in their dull grey colour and no mistake can be made in their picking fr om the sample. The following upper cretaceous forms could be identified : Cristallaria (Robulus) cf. inomata (O' ORB) Nodosaria sp *Gümbelina camagueyana VAN .RMOSHOVEN * G. costulata CUSHMAN *G. excolata CUSHMAN *G. globulosa (EHRENBERG) *G. nuttalli VOORWI]i< *G. plummerae LOETTERLE G. pseudotessera CUSHMAN *G. reussi CUSHMAN *G. striata (EHRENBERG) '* Pseudotextularia varians .RzEHAK '* Planoglobulina acervulinoides ( EGGER) '* Ventilabrella carseyi PUIMMER '* Bolivinoides seranensis VAN DER SLUIS Pulvinulinella culter (PARKER & JONES) '*Globigerina bulloides O'ORBIGNY *G. cretacea D'ORBIGNY '*G. pseudotriloba WHITE *Globigerinella aspera (EHRENBERG) '*Globorotalia crassaformis (GALLOWAY & WISSLER) '*G. membranacea (EHRENBERG) * G. velascoensis (CUSHMAN) '* Globotruncana area (CUSHMAN) 339 .. G. calcarata CUSHMAN "G. canaliculata (REUSS) "G. canaliculata (REUSS), var. ventricosa WHITE "G. convexa SANDlOGE, var. multicamerata VAN OER SLUIS Anomalina bentonensis MORRow A. sp. In th is list species marked by an asterisk have also been found by VAN OER SLUIS in the Upper Cretaceous of Seran (0. E.I.). The re:semblance with that fauna is so great, that both faunae may safely be regarded as ' synchronic (i. e. rather high in the Upper Cretaceous). The cretaceous rocks are known already for a long time through the investigations made on the island by the governmental "Dienst van den Mijnbouw". The knowledge has been summarized by HETZEL 1) in the final report on the asphaltbearing rocks on Boeton. The cretaceous series consists of white, grey and rosy, of ten porcelain-like dense-textured limestones, of ten cut by veinIets of calcite, and containing the typical assemblage of Gümbelina globulosa (EHRENBERG) Globigerina cretacea O'ORBIGNY Globotruncana canaliculata (REUSS). This type of limestone is very common in the eastern part of the East Indian Archipelago. Characteristic for the formation are layers and concretions of reddish and yellow chert, sometimes rich in radiolaria. The dense-textured limestones are ' mentioned to occur sometimes in alternation with white or light-grey marly limestones with locally also layers of chert. In contrast with the first type these limestones contain abundantly Globigerinidae, but no Globotruncana. This may be interpreted as due to changes in facial conditions, but it remains also possible th at the marly Globigerina-limestones belong the another stratigraphic unit than the Globotruncana-limestones. The last possibility leads to the assumption of tectonical complications in the sec ti ons relating to the matter in question. HETZEL'S report, however, is too summary to make a further discussion on this point possible, but the cretaceous series is reported to be strongly folded and sheared. Tectonical complications in Boeton have also been suggested by WANNER (2) for a succession of strata where, according to BOTHÉ (3), upper jurassic limestones are overlain as weil as underlain by Globotruncana ("Rosalina")-limestones ( Cretaceous). LlTERATURE. I. W. H . HETZEL, Verslag van het onderzoek naar het voorkomen van asfaltgesteenten op het eiland Boeton. Verslagen en Mededeelingen betr. Indische delfstoffen, etc. no. 21 Dienst van den Mijnbouw in Neder. Indië (1936). 2. J. WANNER, Gesteinsbildende Foraminiferen aus Malm und Unterkreide des östlichen Ostindischen Archipels. Pal. Ztschr. Bd. 22, p. 75-99 (1940). 3. A. C. D . BOTHE. Voorloopige mededeeling betreffende de geologie van Zuid-OostCelebes. De Mijningenieur V III , p. 97-03 (1927).
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