Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia

The coals and coal-bearing mangrove sediments of Sandakan Formation have been evaluated for their source rock potential, paleoredox conditions and source of organic input, as well as the age and paleovegetation distribution using geochemical and petrographical methods. The studied samples were gener...

Full description

Bibliographic Details
Main Authors: Mustapha, K.A., Abdullah, W.H., Konjing, Z., Gee, S.S., Koraini, A.M.
Format: Article
Published: Elsevier 2017
Subjects:
_version_ 1825720944396599296
author Mustapha, K.A.
Abdullah, W.H.
Konjing, Z.
Gee, S.S.
Koraini, A.M.
author_facet Mustapha, K.A.
Abdullah, W.H.
Konjing, Z.
Gee, S.S.
Koraini, A.M.
author_sort Mustapha, K.A.
collection UM
description The coals and coal-bearing mangrove sediments of Sandakan Formation have been evaluated for their source rock potential, paleoredox conditions and source of organic input, as well as the age and paleovegetation distribution using geochemical and petrographical methods. The studied samples were generally rich in organic carbon, which varied from 0.60 (massive mudstone) to 62.37 wt% (coal). The studied samples have vitrinite reflectance (Ro) ranging from 0.31 to 0.49% and Tmax values ranging from 353 to 436 °C indicating an immature to very early mature stage for hydrocarbon generation. The sediments were dominated by Type III kerogen, with some Type II/III kerogen, suggesting a significant land plant contribution to the organic matter. The bimodal distribution displayed by gas chromatogram, with a clear odd/even carbon number and skewed to higher molecular weight carbon (nC31), indicating a transitional depositional environment. The variation in pristane/phytane ratio, varied from 0.71 to 2.97, suggesting an alternating anoxic and oxic deposition conditions. The presence of marine dinoflagellate cyst in the mangrove and offshore mudstones were consistent with the relatively higher sulphur content in the studied samples which indicate marine inundations. Palynomorph recovered in this study, with abundant mangrove and freshwater types of pollen, suggesting a biogeographical distribution of ancient mangrove vegetation that expanded landward into the freshwater peat swamp setting and hinterland. The presence of marker species, viz. Florschuetzia levipoli, F. meridionalis and F. semilobata delineated an Early Miocene to Middle Miocene age for the Sandakan sediments.
first_indexed 2024-03-06T05:42:50Z
format Article
id um.eprints-17548
institution Universiti Malaya
last_indexed 2024-03-06T05:42:50Z
publishDate 2017
publisher Elsevier
record_format dspace
spelling um.eprints-175482017-07-20T08:04:13Z http://eprints.um.edu.my/17548/ Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia Mustapha, K.A. Abdullah, W.H. Konjing, Z. Gee, S.S. Koraini, A.M. QE Geology The coals and coal-bearing mangrove sediments of Sandakan Formation have been evaluated for their source rock potential, paleoredox conditions and source of organic input, as well as the age and paleovegetation distribution using geochemical and petrographical methods. The studied samples were generally rich in organic carbon, which varied from 0.60 (massive mudstone) to 62.37 wt% (coal). The studied samples have vitrinite reflectance (Ro) ranging from 0.31 to 0.49% and Tmax values ranging from 353 to 436 °C indicating an immature to very early mature stage for hydrocarbon generation. The sediments were dominated by Type III kerogen, with some Type II/III kerogen, suggesting a significant land plant contribution to the organic matter. The bimodal distribution displayed by gas chromatogram, with a clear odd/even carbon number and skewed to higher molecular weight carbon (nC31), indicating a transitional depositional environment. The variation in pristane/phytane ratio, varied from 0.71 to 2.97, suggesting an alternating anoxic and oxic deposition conditions. The presence of marine dinoflagellate cyst in the mangrove and offshore mudstones were consistent with the relatively higher sulphur content in the studied samples which indicate marine inundations. Palynomorph recovered in this study, with abundant mangrove and freshwater types of pollen, suggesting a biogeographical distribution of ancient mangrove vegetation that expanded landward into the freshwater peat swamp setting and hinterland. The presence of marker species, viz. Florschuetzia levipoli, F. meridionalis and F. semilobata delineated an Early Miocene to Middle Miocene age for the Sandakan sediments. Elsevier 2017 Article PeerReviewed Mustapha, K.A. and Abdullah, W.H. and Konjing, Z. and Gee, S.S. and Koraini, A.M. (2017) Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia. CATENA, 158. pp. 30-45. ISSN 0341-8162, DOI https://doi.org/10.1016/j.catena.2017.06.005 <https://doi.org/10.1016/j.catena.2017.06.005>. https://doi.org/10.1016/j.catena.2017.06.005 DOI: 10.1016/j.catena.2017.06.005
spellingShingle QE Geology
Mustapha, K.A.
Abdullah, W.H.
Konjing, Z.
Gee, S.S.
Koraini, A.M.
Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia
title Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia
title_full Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia
title_fullStr Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia
title_full_unstemmed Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia
title_short Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia
title_sort organic geochemistry and palynology of coals and coal bearing mangrove sediments of the neogene sandakan formation northeast sabah malaysia
topic QE Geology
work_keys_str_mv AT mustaphaka organicgeochemistryandpalynologyofcoalsandcoalbearingmangrovesedimentsoftheneogenesandakanformationnortheastsabahmalaysia
AT abdullahwh organicgeochemistryandpalynologyofcoalsandcoalbearingmangrovesedimentsoftheneogenesandakanformationnortheastsabahmalaysia
AT konjingz organicgeochemistryandpalynologyofcoalsandcoalbearingmangrovesedimentsoftheneogenesandakanformationnortheastsabahmalaysia
AT geess organicgeochemistryandpalynologyofcoalsandcoalbearingmangrovesedimentsoftheneogenesandakanformationnortheastsabahmalaysia
AT korainiam organicgeochemistryandpalynologyofcoalsandcoalbearingmangrovesedimentsoftheneogenesandakanformationnortheastsabahmalaysia