Reconstruction of the gross depositional environment evolution in the Northern Malay Basin, Malaysia-Thailand joint development area (MTJDA)
Document Type
Article
Publication Date
10-1-2022
Abstract
This paper provides new insight on the complex interactions between regional tectonic evolution, differential subsidence across the basin, and variation in sediment supply based on a reconstruction of the gross depositional environment in the northern part of Malay Basin. In addition, the variation in sedimentary facies, established from an integrated analysis based on seismic interpretation, well-log analysis, and core evaluation, are used to establish the gross depositional environment for key surfaces within the Oligocene to Miocene succession.The basin fill comprises Oligocene syn-rift and Miocene post-rift successions. The syn-rift successions are Syn-Rift Unconformity (SRU)-Base of Syn-Rift (BSR), and Base Chattian Unconformity (BCU)-Syn-Rift Unconformity (SRU) sequences. Whereas, the post-rift successions represent by Intra-Aquitanian MFS (IAM)-Base Chattian Unconformity (BCU), Intra-Burdigalian MFS (IBM)-Intra-Aquitanian MFS (IAM), Miocene Transgressive-Regressive (MTR)-Intra-Burdigalian MFS (IBM), Intra-Serravalian MFS (ISM)-Miocene Transgressive-Regressive (MTR), and Intra-Tortonian (ITM)-Intra-Serravalian MFS (ISM) sequences.The Oligocene-early Miocene syn-rift succession in the study area is characterized by aggradational stacking patterns, with an indication of retrogradation in individual sand packages for SRU-BSR, and BCU-SRU intervals, whereas an overall aggradational stacking pattern can be observed within the IAM-BCU sequence. The deposi-tional environment of the syn-rift succession is mainly deltaic, fluvial, alluvial fan, shallow and deep lacustrine at the basin center.The early-middle Miocene post-rift succession is characterized by mostly aggradational and fining upwards stacking within the IBM-IAM sequence. This gradually changed to a retrogradational pattern in the MTR-ISM sequence. Depositional environments for this succession consist of an alternation between fluvio-marine and sub-tidal to marine sedimentation. Depositional environments for the overlying late Miocene Intra-Tortonian to Intra-Serravalian (ITM-ISM) was estuarine or tidally-influenced environments comprising fluvial channel, tidal or distributary channel, tidal sand flat, and tidal flat deposition. This interval mainly consists of coarsening upward units that gradually changed to a stacked higher-order fining upwards package. The deeper stratigraphic units are generally more continental (non-marine) in character, but fluvio-tidally influenced marine environ-ments became more dominant in the shallower sequences.
Keywords
Sedimentary depositional evolution, Basin analysis, Sedimentary facies, Oligocene-Miocene sequence, North-Malay Basin
Divisions
GEOLOGY
Funders
Universiti Malaya Institut Pengurusan Penyelidikan dan Pemantauan - international research fund of MTJA,Cess Fund IF064-2019,Institute of Research Management and Services (IPPP) of Universiti Malaya,International research fund of MTJA Cess Fund IF064-2019
Publication Title
Marine and Petroleum Geology
Volume
144
Publisher
Elsevier
Publisher Location
THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND