Palynomorph and palynofacies studies on the lower Miocene succession in the eastern margin of the central trough of Nam Con Son basin
Abstract
Palynofacies study in palynology analysis is an interdisciplinary method of research combining stratigraphy, sedimentology and organic geochemistry to determine the depositional environment and assess the source rock potential. This study was caried out on rock samples collected from the Lower Miocene sediments of the CS1 and CS2 wells at the eastern margin of the central trough of the Nam Con Son basin. The aim of the study is (1) to clarify the sedimentary deposition environment in relation to the physicochemical conditions of the organic matter, (2) to evaluate the thermal maturity of the organic matter, and (3) to assess the source rock potential.
The studied results show that three palynofacies were identified, corresponding to four environmental assemblages belonging to shelf marine sediments; the thermal maturity level of organic matter from immature to mature, in which the thermal maturity level of the CS2 well is higher than that of CS1; the hydrocarbon potential of the source rock is oil prone in palynofacies 1 and gas prone in palynofacies 2 and 3.
Palynofacies study is important in the exploratory phase, providing necessary data to evaluate the hydrocarbon potential of the source rock, in addition to the information obtained from the biostratigraphy and sedimentary petrology analysis.
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