Sedimentology of Moulmein Limestone at Karon-Damathat Area, Kyaikmaraw Township, Mon State, Myanmar

Abstract

Karon-Damathat area is situated in the northern part of Kyaikmaraw Township, Mon State. The investigated area occupies between latitude 16º29ʹ36ʺN to 16º33ʹ24ʺN and longitude 97º42ʹ00ʺE to 97º49ʹ36ʺE. One inch topographic maps are 94H/10 and 94H/14, and areas covering approximately 88km2 (34 square miles). The present research mainly emphasized only on the carbonate sedimentology of the Middle to Late Permian Moulmein Limestone. Karon and Damathat Hill Limestone are composed of micritic limestone, fossiliferous limestone, dolomitic limestone, brecciated limestone and crystalline limestone. It was measured about 62 m and 226m in thicknesss in details for microfacies analysis and were recognized into thirteen microfacies; intraclastic wackestone, dolomitic mudstone, mudstone, algal packstone, peloidal grainstone, peloidal packstone, oolitic grainstone, ostracode bearing mudstone, laminated dolomite-lime mudstone, algal wackestone, bioclastic algal grainstone, peloidal algal wackestone and peloidal mudstone. These microfacies were grouped into three microfacies associations which represent three different depositional environments such as supratidal, intertidal and subtidal environments. In the study of diagenesis, the common diagenetic processes are cementation, micritization, neomorphism, chemical compaction, dolomitization and other diagenetic materials encountered in Moulmein Limestone. Three major diagenetic environments such as the marine environment, meteoric environment and subsurface or burial environment are differentiated. The sequence stratigraphic interpretation of the Karon area indicates that five metre- scale fourth–order shallowing upward parasequence cycles. In Damathat section line, thirteen, metre- scale fourth–order shallowing upward parasequence cycles and two, metre- scale fourth–order deepening upward parasequence cycles are recorded. Thick succession of carbonate sedimentary sequence in Moulmein Limestone mainly consists of second order sequence. In the global Permian sea level, the slow falling of sea level also representing to Middle to Late Permian time which superimpose by lower order smaller cycles.

AAPG Datapages/Search and Discovery Article #90336 ©2018 AAPG Asia Pacific Region, The 4th AAPG/EAGE/MGS Myanmar Oil and Gas Conference, Myanmar: A Global Oil and Gas Hotspot: Unleashing the Petroleum Systems Potential, Yangon, Myanmar, November 13-15, 2018