MICROFACIES DEVELOPMENT OF THE SELAYAR LIMESTONE SOUTH SULAWESI

PROCEEDINGS PIT IAGI RIAU 2006
The 35^th IAGI Annual Convention and Exhibition
Pekanbaru – Riau, 21 – 22 November 2006

MICROFACIES DEVELOPMENT OF THE SELAYAR LIMESTONE SOUTH SULAWESI

A. M. IMRAN ¹
ROMAN KOCH ²

¹ Geological Department, Hasanuddin University, Makassar
² University of Erlangen-Nuernberg, Germany.

ABSTRACT

The Selayar Limestone was mapped as a member of the Walanae Formation and was developed in the southern tip of South Sulawesi during the Late Miocene to the Pliocene (Sukamto & Supriatna 1982). This study, conducted in two areas of eastern Bulukumba, South Sulawesi. The study reveals four reef units of development, which shifted from an older reef formation in the northern part (Bontotiro area) to a younger formation in the southern part (Bira area). The units corresponding to the age of the reefs are the: a) lower Late Miocene B-1 unit. The B-1 Unit of the Bontotiro area is predominantly composed of large foraminiferal limestone, which form knoll-like hills; b) upper Late Miocene to Pliocene B-2 and Upper Terrace Unit. The B-2 Unit in the upper part of the Bontotiro area and the Upper Terrace Unit of the Bira area are considered as the same development unit because they are of the same age; c) Pliocene coralgal reefs of the Middle Terrace Unit. The Middle Terrace Unit is characterized by Halimeda limestone and well-preserved fibrous cements; d) Pleistocene coral reefs of the Lower Terrace. The Lower Terrace Unit is dominated by coral reefs and was formed from reef flank seaward and reef framework leeward.

Keywords: Microfasies, Unit Facies, Terraces, Selayar Limestone.