Uthai Thani-Nakhon Sawan structural ridge is the 35 km mountain length lying in N-S direction within the Chainat duplex at the Central Thailand. The ridge, which is clearly seen from satellite image in the flat areas ...Uthai Thani-Nakhon Sawan structural ridge is the 35 km mountain length lying in N-S direction within the Chainat duplex at the Central Thailand. The ridge, which is clearly seen from satellite image in the flat areas of the Central Plain, is composed of Triassic mylonitic granite and Silurian-Devonian metamorphosed sedimentary rocks. Satellite image interpretation, geological mapping, field data and microstructure analysis have been integrated for the understanding of structural style of Uthai Thani-Nakhon Sawan ridge. The rocks within the ridge had been deformed under sinistral ductile shear which was shown by foliations, stretching lineations, S-C fabrics, sigmoid clasts, mineral fish and S-folded both in outcrops and under microscope. The major N-S, minor NNW-SSE striking ridges and foliation planes indicate the paleostress of σ1 in the NW-SE direction. The major sinistral motion of this region probably ended at ~30 Ma. All structural elements and deformation style of Uthai Thani-Nakhon Sawan ridge relate to the Chainat duplex geometry and Mae Ping fault zone activity during Tertiary.展开更多
The Sawan gas field(SGF)is located in Pakistan's central Indus Basin in the Province of Sindh,Pakistan.Tectonically,it is part of the southeastern Jacobabad high;and geographically,it is part of the Thar Desert in...The Sawan gas field(SGF)is located in Pakistan's central Indus Basin in the Province of Sindh,Pakistan.Tectonically,it is part of the southeastern Jacobabad high;and geographically,it is part of the Thar Desert in the Khairpur district.In the present study,three wells,Sawan 01,Sawan 02 and Sawan 08,were analyzed for reservoir properties of the Lower Goru C sand interval,which has been drilled in the central part of the field.Petrophysical parameters such as effective porosity,the volume of shale,formation water resistivity,and water saturation of the studied basin were calculated.In terms of shale volume,Sawan 01 has 30%–35%of non-clean(shale)lithology,which is the highest of the three wells.The effective porosity of the three wells ranges from 12%–16%,while the average water saturation in the interval of C sand in these wells stands around 50%–60%.But there are zones with relatively lower water saturation values of approximately 30%–50%.These zones are considered better pay zones than the rest of the intervals.A very interesting phenomenon that may be termed the"Gas effect"is visible on cross plots,representing the neutron-density cross over on the E-Logs layout and representing the presence of lighter hydrocarbons in this reservoir zone.展开更多
The Lower Indus Basin is the leading hydrocarbon-bearing sedimentary basin in Pakistan.This study has been conducted on the Sawan gas field located in the Lower Indus Basin,adjacent to a few other wellknown gas fields...The Lower Indus Basin is the leading hydrocarbon-bearing sedimentary basin in Pakistan.This study has been conducted on the Sawan gas field located in the Lower Indus Basin,adjacent to a few other wellknown gas fields of Pakistan like Kadanwari,Qadirpur,and Miano gas fields.This research aims to present the spatial distribution and reservoir potential of the productive zones of the Lower Goru Formation.The present study utilized various two-dimensional(2D)seismic lines and well-log data(Sawan-01 and Sawan-02)to investigate the structural and stratigraphic features of the area.The stratigraphic layers are mildly deepening in the southeast direction.The 2D seismic interpretation of the research area identifies the existence of extensional remanents,i.e.,normal faults.These extensional structures are associated with horst and graben geometry that acts as a trapping mechanism for hydrocarbons.Wireline logs are used to identify the reservoir's diverse lithology and petrophysical properties.Petrophysical results indicate fair to good effective porosities,low shale volume,and high hydrocarbon saturation(>55%),signifying good reservoir potential in C interval of the Lower Goru Formation.展开更多
基金funded by the Ratchadaphiseksomphot Endowment Fund, Chulalongkorn Universityfunded by the Department of Geology, Faculty of Science, Chulalongkorn University
文摘Uthai Thani-Nakhon Sawan structural ridge is the 35 km mountain length lying in N-S direction within the Chainat duplex at the Central Thailand. The ridge, which is clearly seen from satellite image in the flat areas of the Central Plain, is composed of Triassic mylonitic granite and Silurian-Devonian metamorphosed sedimentary rocks. Satellite image interpretation, geological mapping, field data and microstructure analysis have been integrated for the understanding of structural style of Uthai Thani-Nakhon Sawan ridge. The rocks within the ridge had been deformed under sinistral ductile shear which was shown by foliations, stretching lineations, S-C fabrics, sigmoid clasts, mineral fish and S-folded both in outcrops and under microscope. The major N-S, minor NNW-SSE striking ridges and foliation planes indicate the paleostress of σ1 in the NW-SE direction. The major sinistral motion of this region probably ended at ~30 Ma. All structural elements and deformation style of Uthai Thani-Nakhon Sawan ridge relate to the Chainat duplex geometry and Mae Ping fault zone activity during Tertiary.
文摘The Sawan gas field(SGF)is located in Pakistan's central Indus Basin in the Province of Sindh,Pakistan.Tectonically,it is part of the southeastern Jacobabad high;and geographically,it is part of the Thar Desert in the Khairpur district.In the present study,three wells,Sawan 01,Sawan 02 and Sawan 08,were analyzed for reservoir properties of the Lower Goru C sand interval,which has been drilled in the central part of the field.Petrophysical parameters such as effective porosity,the volume of shale,formation water resistivity,and water saturation of the studied basin were calculated.In terms of shale volume,Sawan 01 has 30%–35%of non-clean(shale)lithology,which is the highest of the three wells.The effective porosity of the three wells ranges from 12%–16%,while the average water saturation in the interval of C sand in these wells stands around 50%–60%.But there are zones with relatively lower water saturation values of approximately 30%–50%.These zones are considered better pay zones than the rest of the intervals.A very interesting phenomenon that may be termed the"Gas effect"is visible on cross plots,representing the neutron-density cross over on the E-Logs layout and representing the presence of lighter hydrocarbons in this reservoir zone.
文摘The Lower Indus Basin is the leading hydrocarbon-bearing sedimentary basin in Pakistan.This study has been conducted on the Sawan gas field located in the Lower Indus Basin,adjacent to a few other wellknown gas fields of Pakistan like Kadanwari,Qadirpur,and Miano gas fields.This research aims to present the spatial distribution and reservoir potential of the productive zones of the Lower Goru Formation.The present study utilized various two-dimensional(2D)seismic lines and well-log data(Sawan-01 and Sawan-02)to investigate the structural and stratigraphic features of the area.The stratigraphic layers are mildly deepening in the southeast direction.The 2D seismic interpretation of the research area identifies the existence of extensional remanents,i.e.,normal faults.These extensional structures are associated with horst and graben geometry that acts as a trapping mechanism for hydrocarbons.Wireline logs are used to identify the reservoir's diverse lithology and petrophysical properties.Petrophysical results indicate fair to good effective porosities,low shale volume,and high hydrocarbon saturation(>55%),signifying good reservoir potential in C interval of the Lower Goru Formation.
