Carbonates of Central Luconia, Malaysia, had been serving as hydrocarbon reservoirs for more than 25 years. However, the relationship and impacts of extensive tectonic events to the growth of Miocene carbonates in Cen...Carbonates of Central Luconia, Malaysia, had been serving as hydrocarbon reservoirs for more than 25 years. However, the relationship and impacts of extensive tectonic events to the growth of Miocene carbonates in Central Luconia have not been revealed sufficiently. In this work, two carbonates platforms in the southern part of Central Luconia were used for detailed interpretation and seismic based structural restoration. This work had provided new insight for the interpreta- tion of carbonate growth in Central Luconia and its association with the surrounding tectonic. This work suggested three possible tectonic evolutions from Late Oligocene to Pliocene are responsible for the growth of carbonates in Central Luconia. These stages are equivalent with pre-carbonate stage （Late Oligocene-Early Miocene）, syn-carbonate stage （Middle-Late Miocene） and post-carbonate stage （Pliocene）. Rifting of the South China Sea and subduction of proto-South China Sea are believed to be responsible for the development of faulting during pre-carbonate stage, while movement of the ancient Baram Line is thought to control the parallel striking direction of normal faults during syn- carbonate stage. Finally, subsidence and compaction due to the overburden clastic materials from the prograding deltas is considered as the main reason for the impacts of gravitational tectonics in this area, which corresponding to the post-carbonate stage.展开更多
The Luconia Province-offshore Sarawak-is a key geological unit for understanding the distribution of hydrocarbon resources in Malaysia. Nevertheless, little effort has been made to address the palaeoenvironmental char...The Luconia Province-offshore Sarawak-is a key geological unit for understanding the distribution of hydrocarbon resources in Malaysia. Nevertheless, little effort has been made to address the palaeoenvironmental characteristics of the Tertiary carbonates in the key sector of Central Luconia.We study the sedimentology and petrography of core samples from a well in Central Luconia, for which thirteen microfacies have been identified reflecting different depositional settings. This is the first microfacies scheme elaborated for Luconian carbonates. Lithofacies and microfacies distribution are compatible with deposition in a reef complex, originating around a framework reef, within the euphotic zone. Sediments were deposited in environments of backreef, reef crest, and forereef. The fair weather wave base is marked by the presence of coralline red algae, foraminifera, decreasing degree of bioclast fragmentation and other microfacies features. As a result, a depositional-environmental model is constructed, depicting a reef complex built around a framework reef developed on the margin of an isolated platform. In addition, an innovative, preliminary time series analysis of facies, microfacies and depositional environment data reveal the existence of seasonal cycles in the stacking patterns of facies and microfacies.展开更多
基金Universiti Teknologi PETRONAS, PETRONAS and SHELL for their financial support
文摘Carbonates of Central Luconia, Malaysia, had been serving as hydrocarbon reservoirs for more than 25 years. However, the relationship and impacts of extensive tectonic events to the growth of Miocene carbonates in Central Luconia have not been revealed sufficiently. In this work, two carbonates platforms in the southern part of Central Luconia were used for detailed interpretation and seismic based structural restoration. This work had provided new insight for the interpreta- tion of carbonate growth in Central Luconia and its association with the surrounding tectonic. This work suggested three possible tectonic evolutions from Late Oligocene to Pliocene are responsible for the growth of carbonates in Central Luconia. These stages are equivalent with pre-carbonate stage （Late Oligocene-Early Miocene）, syn-carbonate stage （Middle-Late Miocene） and post-carbonate stage （Pliocene）. Rifting of the South China Sea and subduction of proto-South China Sea are believed to be responsible for the development of faulting during pre-carbonate stage, while movement of the ancient Baram Line is thought to control the parallel striking direction of normal faults during syn- carbonate stage. Finally, subsidence and compaction due to the overburden clastic materials from the prograding deltas is considered as the main reason for the impacts of gravitational tectonics in this area, which corresponding to the post-carbonate stage.
基金financial assistance throughout the research under the grant YUTP 0153AAA14financial support from UTP through the grant URIF 2014-00735
文摘The Luconia Province-offshore Sarawak-is a key geological unit for understanding the distribution of hydrocarbon resources in Malaysia. Nevertheless, little effort has been made to address the palaeoenvironmental characteristics of the Tertiary carbonates in the key sector of Central Luconia.We study the sedimentology and petrography of core samples from a well in Central Luconia, for which thirteen microfacies have been identified reflecting different depositional settings. This is the first microfacies scheme elaborated for Luconian carbonates. Lithofacies and microfacies distribution are compatible with deposition in a reef complex, originating around a framework reef, within the euphotic zone. Sediments were deposited in environments of backreef, reef crest, and forereef. The fair weather wave base is marked by the presence of coralline red algae, foraminifera, decreasing degree of bioclast fragmentation and other microfacies features. As a result, a depositional-environmental model is constructed, depicting a reef complex built around a framework reef developed on the margin of an isolated platform. In addition, an innovative, preliminary time series analysis of facies, microfacies and depositional environment data reveal the existence of seasonal cycles in the stacking patterns of facies and microfacies.
