A description on the petroleum system of BangladeshShahadat Saimon
This document provides an overview of the petroleum system of the Bengal Basin, which covers Bangladesh and parts of India. It discusses the basin's geological setting, stratigraphy, tectonic evolution, and three petroleum provinces - the Eastern Fold Belt, Central Foredeep, and Northwestern Stable Shelf/Platform. The key points are:
- The Bengal Basin was formed during the breakup of Gondwanaland in the Cretaceous period.
- It has over 20km of sedimentary deposits and multiple petroleum systems in Miocene sands.
- The Eastern Fold Belt contains the majority of Bangladesh's gas fields in structures like anticlines.
- The Central Foredeep is also
1. Bangladesh's geology consists of four folded belts, with the eastern regions exhibiting many anticlines and synclines trending NNW-SSE.
2. Small hillocks in northern districts trend E-W, while subsurface sediments on the Dinajpur Shield dip and fold.
3. Subsurface folding below the delta region involves anticlines up to 10 km deep.
4. Major faults trend NW-SE, NE-SW, and were active from the Precambrian to post-Pleistocene.
Bangladesh has a diverse physiography that can be divided into 7 regions: 1) Hilly regions along the southeast and northeast border, reaching up to 1003 meters high. 2) Pleistocene uplands including the Barind and Madhupur tracts, elevated red clay deposits reaching up to 20 meters high. 3) The Tista Fan, an alluvial plain extending from the Himalayan foothills southward. 4) Flood plains covering 40% of the country at elevations of 3-5 meters above sea level. 5) The delta plain of the Ganges-Brahmaputra-Meghna rivers covering 32% of the country. 6) The Sylhet Depression, a
The term "trap" has been used in geology since 1785–95 for rock formations. It is derived from the Swedish word for stairs (trapp , trappa) and refers to the step-like hills forming the landscape of the region.
The plateau: also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A plateau is an elevated land. It is a flat-topped table standing above the surrounding area. A plateau may have one or more sides with steep slopes.
LIP – Large Igneous provinces. (Province = Area / Region)
DVP - The Deccan Volcanic Province is one of the Earth’s giant continental flood basalts and has a total exposed area of about half a million square kilometers in Maharashtra, Madhya Pradesh, Gujrat and some part of Andhra Pradesh. Deccan trap has maximum thickness 3400m in western ghat and its thickness goes decrease toward east side. At Amrakantat on east its thickness is just 160m. Geographical distribution is between latitudes 16° - 24° N and longitudes 70° - 77° E.
The document provides an overview of the geological history and tectonic evolution of the Himalayan mountain range over the past 55 million years. It describes how the collision of the Indian and Eurasian tectonic plates led to the formation of the mountain range in five phases: 1) Uplift of the Trans-Himalaya region 55-35 million years ago, 2) Deformation of the Tethyan Himalaya 45-35 million years ago, 3) Uplift of the Higher Himalaya 24-17 million years ago, 4) Uplift of the Lesser Himalaya 11-7 million years ago, and 5) Continued uplift through movement along thrust faults from north to south
A description on the petroleum system of BangladeshShahadat Saimon
This document provides an overview of the petroleum system of the Bengal Basin, which covers Bangladesh and parts of India. It discusses the basin's geological setting, stratigraphy, tectonic evolution, and three petroleum provinces - the Eastern Fold Belt, Central Foredeep, and Northwestern Stable Shelf/Platform. The key points are:
- The Bengal Basin was formed during the breakup of Gondwanaland in the Cretaceous period.
- It has over 20km of sedimentary deposits and multiple petroleum systems in Miocene sands.
- The Eastern Fold Belt contains the majority of Bangladesh's gas fields in structures like anticlines.
- The Central Foredeep is also
1. Bangladesh's geology consists of four folded belts, with the eastern regions exhibiting many anticlines and synclines trending NNW-SSE.
2. Small hillocks in northern districts trend E-W, while subsurface sediments on the Dinajpur Shield dip and fold.
3. Subsurface folding below the delta region involves anticlines up to 10 km deep.
4. Major faults trend NW-SE, NE-SW, and were active from the Precambrian to post-Pleistocene.
Bangladesh has a diverse physiography that can be divided into 7 regions: 1) Hilly regions along the southeast and northeast border, reaching up to 1003 meters high. 2) Pleistocene uplands including the Barind and Madhupur tracts, elevated red clay deposits reaching up to 20 meters high. 3) The Tista Fan, an alluvial plain extending from the Himalayan foothills southward. 4) Flood plains covering 40% of the country at elevations of 3-5 meters above sea level. 5) The delta plain of the Ganges-Brahmaputra-Meghna rivers covering 32% of the country. 6) The Sylhet Depression, a
The term "trap" has been used in geology since 1785–95 for rock formations. It is derived from the Swedish word for stairs (trapp , trappa) and refers to the step-like hills forming the landscape of the region.
The plateau: also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A plateau is an elevated land. It is a flat-topped table standing above the surrounding area. A plateau may have one or more sides with steep slopes.
LIP – Large Igneous provinces. (Province = Area / Region)
DVP - The Deccan Volcanic Province is one of the Earth’s giant continental flood basalts and has a total exposed area of about half a million square kilometers in Maharashtra, Madhya Pradesh, Gujrat and some part of Andhra Pradesh. Deccan trap has maximum thickness 3400m in western ghat and its thickness goes decrease toward east side. At Amrakantat on east its thickness is just 160m. Geographical distribution is between latitudes 16° - 24° N and longitudes 70° - 77° E.
The document provides an overview of the geological history and tectonic evolution of the Himalayan mountain range over the past 55 million years. It describes how the collision of the Indian and Eurasian tectonic plates led to the formation of the mountain range in five phases: 1) Uplift of the Trans-Himalaya region 55-35 million years ago, 2) Deformation of the Tethyan Himalaya 45-35 million years ago, 3) Uplift of the Higher Himalaya 24-17 million years ago, 4) Uplift of the Lesser Himalaya 11-7 million years ago, and 5) Continued uplift through movement along thrust faults from north to south
The document provides an outline of a class on geo-data and location. It discusses different types of location including absolute and relative location. Absolute location uses coordinates like latitude and longitude while relative location describes position based on other locations. The document then covers locational importance from geophysical, economic, and geopolitical perspectives. Finally, it examines how Bangladesh's geographical location contributes to hazards like floods and cyclones through factors such as monsoon climate, mountainous surroundings, low floodplain gradient, and proximity to the Bay of Bengal.
The document summarizes the morphology and features of the ocean floor. It describes key features such as continental margins consisting of continental shelves, slopes, and rises. It also discusses ocean basins and their abyssal plains and hills, as well as mid-ocean ridges, trenches, seamounts, and guyots that form undersea volcanoes. Plateaus and island arcs are also mentioned. In conclusion, the ocean floor varies significantly in shape and size due to ongoing crustal movements from plate tectonics.
The document summarizes the Cudappah Supergroup, an important Proterozoic sedimentary basin in India. It describes the basin's lithostratigraphy, which includes groups like the Papaghni, Chitravati, Nallamalai, and Srisailam quartzites. The basin provides economic resources like barytes, chrysotile, asbestos, steatite, diamonds, uranium, and building/ornamental stones. Radiometric dating indicates the basin formed between 1500-1800 million years ago. The Cudappah Supergroup is a significant paleo-Mesoproterozoic basin that records much of India's early geological history.
Coastal Geomorphology Landforms Of Wave Erosion & DepositionPRasad PK
This document discusses various coastal landforms and processes. It defines coastal geomorphology and describes how waves, longshore currents, rip currents, and tides shape coastal areas and transport sediment. It then lists and describes specific coastal landforms like headlands, bays, sea cliffs, beaches, bars, spits, tombolos, sand dunes, salt marshes, and more. For each landform, it provides a brief definition and example photo. Coastal erosion processes like abrasion, hydraulic action, corrosion, and attrition are also outlined.
The Deccan Traps formed during the late Cretaceous period through volcanic eruptions in western, central, and southern India. The eruptions resulted in enormous lava flows that covered over 1.5 million square kilometers. The lava cooled to form thick basalt deposits in some places over 3000 meters thick. The Deccan Traps are classified into upper, middle, and lower sections. They overlie various older rock formations and contain intertrappean beds. The volcanic rocks mainly consist of basalt and have economic uses as building material and as a source of minerals.
Drainage pattern and their significanceAvinashAvi110
The document discusses drainage patterns, their classification, and significance. It outlines different types of drainage patterns including dendritic, trellis, rectangular, parallel, and radial patterns. Drainage patterns are influenced by factors like slope, rock type, geologic structures, climate, and geomorphic history. Improper drainage can lead to flooding while well-developed drainage increases water storage and supplies, supports irrigation, and affects groundwater potential and sustainability. Different drainage patterns reveal information about the underlying geology.
This technical paper provides an overview of the major sedimentary basins in India that contain hydrocarbon reserves. It divides the basins into four categories based on the status of hydrocarbon exploration and production. The key basins discussed in detail include the Assam Shelf Basin, Cambay Basin, Bombay Offshore Basin, and Krishna-Godavari Basin. For each basin, it summarizes the geological setting, stratigraphy, hydrocarbon source rocks and reservoir rocks. The paper provides a high-level technical summary of India's major sedimentary basins with proven oil and gas reserves.
This document provides a detailed overview of the stratigraphy, lithology, structure, tectonics, and mineral resources of Meghalaya, India. It discusses the geological formations in the region from the Precambrian basement rocks up through more recent Cretaceous and Tertiary sediments. Key formations include the Shillong Group metasedimentary rocks and Khasi Greenstone volcanic rocks from the Proterozoic, as well as the overlying Khasi, Jaintia, and Garo Groups of sedimentary rocks ranging from the Cretaceous to Tertiary periods. The structure of the Shillong Plateau is influenced by numerous faults and was uplifted starting in the Tert
Concept 1. The same physical processes and laws that operate today operated throughout geologic time, although not necessarily always with the same intensity as now.
Concept 2. Geologic structure is a dominant control factor in the evolution of land forms and is reflected in them.
King's geomorphic model is based on the evolution of idealized hill slopes through four stages - waxing slope, free face, debris slope, and waning slope or pediment. The model involves the parallel retreat of scarps and formation of pediments, resulting in the development of a pediplain landscape over multiple cycles of scarp retreat and pedimentation. Each cycle progresses through youth, mature, and old stages similar to Davis' cycle of erosion. The model was developed based on King's extensive study of landscapes in South Africa.
The document summarizes the major cratons found in India, including the Dharwar, Bastar, Singhbhum, Bundelkhand, and Aravalli cratons. It describes the geographic distribution, rock types, ages, and tectonic evolution of each craton. Key events in the evolution of the Indian cratons included continental crust formation over 3 billion years ago, greenstone belt formation and granite intrusion between 2.8-2.5 billion years ago, and collision and deformation between 3-2 billion years ago.
The document summarizes the geology of the Bundelkhand craton located in central India. The craton covers an area of 26,000 square kilometers and contains three main components: enclaves of supracrustal rocks within older gneisses, the Bundelkhand granite and associated quartz reefs and volcanic rocks, and mafic dyke swarms. The craton has undergone tectonic evolution characterized by three primary shear zone orientations: east-west, northeast-southwest, and northwest-southeast.
Boundary problems between :-
Precambrian/Cambrian
Permian/Triassic
Cretaceous/Tertiary
Neogene/Quaternary
Stratigraphic boundaries are determined by one or more of geological events such as volcanic activity, sedimentation, tectonism, paleo-environments & evolution of life.
Faunal records have played major role in determining the boundaries of the Phanerozoic units.
The other geological events are dated on the evidence of fossil records.
Kutch is an East-west Oriented pericraton Rift basin Situated between Nagar Parkar Fault in North and Kathiawar Uplift in South.
Here we will discuss Geology and its Sequence Stratigraphy.
Sea Water Intrusion(SWI) in coastal areas :
1. Occurrence of seawater intrusion
2.Factors that affect coastal aquifer
3.Changes by hydrological regime
4.Problems due to SWI
5.Ghyben-Herzberg relation
6.Methods to detect SWI
7.Control measures
Groundwater province is an area or region in which geology and climate combine to produce groundwater conditions consistent enough to permit useful generalisations.
1. The geographical cycle of erosion recognizes that landscapes undergo planation over time through erosion processes, eventually reducing relief to a minimum.
2. William Davis defined the cycle as having three stages - youth, maturity, and old age - based on changes in erosion rates and landscape morphology.
3. Walther Penck modified Davis' model by proposing that erosion and uplift occur continuously in interaction, and that landscape evolution depends on their relative rates.
This document discusses the Precambrian geology of the Southern Granulite Terrain of India. It describes the terrain as being composed of several blocks separated by shear zones, which experienced high-grade metamorphism and multiple periods of folding and faulting. The metamorphic history involved ultra-high temperature conditions in some areas, as evidenced by mineral assemblages. The document also outlines two competing tectonic models to explain the evolution of the related Pandyan Mobile Belt: a subduction-collision model and an accretion model.
This notes provide the information about tectonic divisions and evolution of Himalayas. movement of Indian plate has also taken up in brief.
Tectonic Division of Himalaya
Evolution of Himalaya
Movement of Indian Plate.
Resource description_ Rasoul Sorkhabi, The himalayan Journal, 2010
This document discusses the Dharwar Super Group found in the Dharwar Craton of India. The Dharwar Craton is divided into the Western and Eastern Dharwar cratons, separated by the Chitradurga shear zone. The Western Dharwar craton contains two prominent super belts: the Bababudan-Western Ghats-Shimoga super belt and the Chitradurga-Gadag super belt, which are part of the Dharwar super group. The Eastern Dharwar craton also contains formations from the Dharwar super group, divided into the Kolar and Yashwantanagar formations. The document concludes that the Dharwar super
Tectonic Framework Tectonic Framework of Bengal Basin.pptxAlMamun560346
The document summarizes the major tectonic units and structural features of the Bengal Basin. It describes three main units: 1) the stable platform in the west-northwest, 2) the geosynclinal basin in the east-northeast, and 3) the hinge zone that separates the two. Within these units it outlines several structural provinces including the Rangpur saddle, stable shelf, hinge zone, Bengal Foredeep, and Chittagong-Tripura Fold Belt. It provides details on the structural characteristics and geological history of these various zones that make up the complex tectonic framework of the Bengal Basin.
The document summarizes the major tectonic units and geological history of Bangladesh. It describes how Bangladesh is divided into a stable Precambrian platform in the northwest and a geosynclinal basin in the southeast, separated by a hinge zone. It details how the Bengal Basin was formed by the collision of the Indian and Asian tectonic plates, resulting in the deposition of thick sedimentary layers over time from the folding of the Himalayas. The document also discusses ongoing neotectonic activity in the region like subsidence and uplift.
The document provides an outline of a class on geo-data and location. It discusses different types of location including absolute and relative location. Absolute location uses coordinates like latitude and longitude while relative location describes position based on other locations. The document then covers locational importance from geophysical, economic, and geopolitical perspectives. Finally, it examines how Bangladesh's geographical location contributes to hazards like floods and cyclones through factors such as monsoon climate, mountainous surroundings, low floodplain gradient, and proximity to the Bay of Bengal.
The document summarizes the morphology and features of the ocean floor. It describes key features such as continental margins consisting of continental shelves, slopes, and rises. It also discusses ocean basins and their abyssal plains and hills, as well as mid-ocean ridges, trenches, seamounts, and guyots that form undersea volcanoes. Plateaus and island arcs are also mentioned. In conclusion, the ocean floor varies significantly in shape and size due to ongoing crustal movements from plate tectonics.
The document summarizes the Cudappah Supergroup, an important Proterozoic sedimentary basin in India. It describes the basin's lithostratigraphy, which includes groups like the Papaghni, Chitravati, Nallamalai, and Srisailam quartzites. The basin provides economic resources like barytes, chrysotile, asbestos, steatite, diamonds, uranium, and building/ornamental stones. Radiometric dating indicates the basin formed between 1500-1800 million years ago. The Cudappah Supergroup is a significant paleo-Mesoproterozoic basin that records much of India's early geological history.
Coastal Geomorphology Landforms Of Wave Erosion & DepositionPRasad PK
This document discusses various coastal landforms and processes. It defines coastal geomorphology and describes how waves, longshore currents, rip currents, and tides shape coastal areas and transport sediment. It then lists and describes specific coastal landforms like headlands, bays, sea cliffs, beaches, bars, spits, tombolos, sand dunes, salt marshes, and more. For each landform, it provides a brief definition and example photo. Coastal erosion processes like abrasion, hydraulic action, corrosion, and attrition are also outlined.
The Deccan Traps formed during the late Cretaceous period through volcanic eruptions in western, central, and southern India. The eruptions resulted in enormous lava flows that covered over 1.5 million square kilometers. The lava cooled to form thick basalt deposits in some places over 3000 meters thick. The Deccan Traps are classified into upper, middle, and lower sections. They overlie various older rock formations and contain intertrappean beds. The volcanic rocks mainly consist of basalt and have economic uses as building material and as a source of minerals.
Drainage pattern and their significanceAvinashAvi110
The document discusses drainage patterns, their classification, and significance. It outlines different types of drainage patterns including dendritic, trellis, rectangular, parallel, and radial patterns. Drainage patterns are influenced by factors like slope, rock type, geologic structures, climate, and geomorphic history. Improper drainage can lead to flooding while well-developed drainage increases water storage and supplies, supports irrigation, and affects groundwater potential and sustainability. Different drainage patterns reveal information about the underlying geology.
This technical paper provides an overview of the major sedimentary basins in India that contain hydrocarbon reserves. It divides the basins into four categories based on the status of hydrocarbon exploration and production. The key basins discussed in detail include the Assam Shelf Basin, Cambay Basin, Bombay Offshore Basin, and Krishna-Godavari Basin. For each basin, it summarizes the geological setting, stratigraphy, hydrocarbon source rocks and reservoir rocks. The paper provides a high-level technical summary of India's major sedimentary basins with proven oil and gas reserves.
This document provides a detailed overview of the stratigraphy, lithology, structure, tectonics, and mineral resources of Meghalaya, India. It discusses the geological formations in the region from the Precambrian basement rocks up through more recent Cretaceous and Tertiary sediments. Key formations include the Shillong Group metasedimentary rocks and Khasi Greenstone volcanic rocks from the Proterozoic, as well as the overlying Khasi, Jaintia, and Garo Groups of sedimentary rocks ranging from the Cretaceous to Tertiary periods. The structure of the Shillong Plateau is influenced by numerous faults and was uplifted starting in the Tert
Concept 1. The same physical processes and laws that operate today operated throughout geologic time, although not necessarily always with the same intensity as now.
Concept 2. Geologic structure is a dominant control factor in the evolution of land forms and is reflected in them.
King's geomorphic model is based on the evolution of idealized hill slopes through four stages - waxing slope, free face, debris slope, and waning slope or pediment. The model involves the parallel retreat of scarps and formation of pediments, resulting in the development of a pediplain landscape over multiple cycles of scarp retreat and pedimentation. Each cycle progresses through youth, mature, and old stages similar to Davis' cycle of erosion. The model was developed based on King's extensive study of landscapes in South Africa.
The document summarizes the major cratons found in India, including the Dharwar, Bastar, Singhbhum, Bundelkhand, and Aravalli cratons. It describes the geographic distribution, rock types, ages, and tectonic evolution of each craton. Key events in the evolution of the Indian cratons included continental crust formation over 3 billion years ago, greenstone belt formation and granite intrusion between 2.8-2.5 billion years ago, and collision and deformation between 3-2 billion years ago.
The document summarizes the geology of the Bundelkhand craton located in central India. The craton covers an area of 26,000 square kilometers and contains three main components: enclaves of supracrustal rocks within older gneisses, the Bundelkhand granite and associated quartz reefs and volcanic rocks, and mafic dyke swarms. The craton has undergone tectonic evolution characterized by three primary shear zone orientations: east-west, northeast-southwest, and northwest-southeast.
Boundary problems between :-
Precambrian/Cambrian
Permian/Triassic
Cretaceous/Tertiary
Neogene/Quaternary
Stratigraphic boundaries are determined by one or more of geological events such as volcanic activity, sedimentation, tectonism, paleo-environments & evolution of life.
Faunal records have played major role in determining the boundaries of the Phanerozoic units.
The other geological events are dated on the evidence of fossil records.
Kutch is an East-west Oriented pericraton Rift basin Situated between Nagar Parkar Fault in North and Kathiawar Uplift in South.
Here we will discuss Geology and its Sequence Stratigraphy.
Sea Water Intrusion(SWI) in coastal areas :
1. Occurrence of seawater intrusion
2.Factors that affect coastal aquifer
3.Changes by hydrological regime
4.Problems due to SWI
5.Ghyben-Herzberg relation
6.Methods to detect SWI
7.Control measures
Groundwater province is an area or region in which geology and climate combine to produce groundwater conditions consistent enough to permit useful generalisations.
1. The geographical cycle of erosion recognizes that landscapes undergo planation over time through erosion processes, eventually reducing relief to a minimum.
2. William Davis defined the cycle as having three stages - youth, maturity, and old age - based on changes in erosion rates and landscape morphology.
3. Walther Penck modified Davis' model by proposing that erosion and uplift occur continuously in interaction, and that landscape evolution depends on their relative rates.
This document discusses the Precambrian geology of the Southern Granulite Terrain of India. It describes the terrain as being composed of several blocks separated by shear zones, which experienced high-grade metamorphism and multiple periods of folding and faulting. The metamorphic history involved ultra-high temperature conditions in some areas, as evidenced by mineral assemblages. The document also outlines two competing tectonic models to explain the evolution of the related Pandyan Mobile Belt: a subduction-collision model and an accretion model.
This notes provide the information about tectonic divisions and evolution of Himalayas. movement of Indian plate has also taken up in brief.
Tectonic Division of Himalaya
Evolution of Himalaya
Movement of Indian Plate.
Resource description_ Rasoul Sorkhabi, The himalayan Journal, 2010
This document discusses the Dharwar Super Group found in the Dharwar Craton of India. The Dharwar Craton is divided into the Western and Eastern Dharwar cratons, separated by the Chitradurga shear zone. The Western Dharwar craton contains two prominent super belts: the Bababudan-Western Ghats-Shimoga super belt and the Chitradurga-Gadag super belt, which are part of the Dharwar super group. The Eastern Dharwar craton also contains formations from the Dharwar super group, divided into the Kolar and Yashwantanagar formations. The document concludes that the Dharwar super
Tectonic Framework Tectonic Framework of Bengal Basin.pptxAlMamun560346
The document summarizes the major tectonic units and structural features of the Bengal Basin. It describes three main units: 1) the stable platform in the west-northwest, 2) the geosynclinal basin in the east-northeast, and 3) the hinge zone that separates the two. Within these units it outlines several structural provinces including the Rangpur saddle, stable shelf, hinge zone, Bengal Foredeep, and Chittagong-Tripura Fold Belt. It provides details on the structural characteristics and geological history of these various zones that make up the complex tectonic framework of the Bengal Basin.
The document summarizes the major tectonic units and geological history of Bangladesh. It describes how Bangladesh is divided into a stable Precambrian platform in the northwest and a geosynclinal basin in the southeast, separated by a hinge zone. It details how the Bengal Basin was formed by the collision of the Indian and Asian tectonic plates, resulting in the deposition of thick sedimentary layers over time from the folding of the Himalayas. The document also discusses ongoing neotectonic activity in the region like subsidence and uplift.
The document provides information on the major geological divisions or cratons of India. It discusses five main cratons - Dharwar, Bastar, Singhbhum, Bundelkhand, and Aravalli. For each craton, it provides details on their location, key rock units, structural features, and tectonic evolution. It also briefly summarizes the economic deposits found within the Aravalli craton, including lead-zinc, gypsum, marble, and others.
The document summarizes the tectonics of Pakistan. It discusses that Pakistan lies at the intersection of three tectonic plates and is seismically active. It describes the major tectonic segments of Pakistan as the:
1) Chaman Transform Zone
2) Northern Collision Belt
3) Platform Areas
4) Subduction Complex Association of Balochistan
5) Ophiolites and Ophiolite Mélanges
It provides details on the structures, features, and rock sequences that characterize each of these tectonic segments.
The document summarizes key information about three sedimentary basins in western India:
1) The Kutch Basin formed in the Late Triassic due to rifting along the Delhi trend. It contains up to 3,000m of sediments from the Late Triassic to Early Cretaceous deposited in marine to deltaic environments.
2) The Saurashtra Basin lies north of proven Mumbai Offshore Basin and south of prospective Kutch Basin. It contains Mesozoic rocks and is covered by Deccan Traps, hindering exploration. Potential reservoirs include Cretaceous sandstones and Eocene-Miocene carbonates.
3) The Narmada Basin formed in the Early
Topography and sediments of the floor of the Bay of BengalMd Hasan Tareq
The Bay of Bengal exhibits a diverse and complex topography on its seafloor, characterized by deep trenches, abyssal plains, submarine canyons, seamounts, and volcanic ridges.
The topography is influenced by tectonic processes, sediment accumulation from the Himalayas, and river transport.
The sediment distribution patterns in the Bay of Bengal are influenced by various factors, including river inputs, ocean currents, and seafloor topography.
The document describes the major sedimentary basins of Pakistan, including their geological histories and structural configurations. It discusses two main basins: the Indus Basin, which is divided into upper and lower sub-basins, and the Balochistan Basin. The Indus Basin evolved over time due to the interaction of the Indian and Eurasian tectonic plates and contains a variety of depositional environments ranging from shallow marine to fluvial. Key structural features such as the Sargodha High influenced sedimentation patterns within the basin.
Alluvial & forming process in baangladeshmd Siraj
This document summarizes the geology and geomorphology of Bangladesh. It describes four key aspects: morphology, hydrology, Quaternary deposits, and the deltaic and wetland environment. The country can be divided into a stable platform to the north with thin sedimentary deposits, and a deep geosynclinal basin to the south with thick sediment deposits from the Ganges-Brahmaputra rivers and folding from tectonic activity. The Quaternary deposits consist of Pleistocene clay and Holocene alluvium from these major river systems that dominate the deltaic landscape of Bangladesh.
Structural Tectonics and Petroleum System of Krishna Godaveri BasinFUCKAGAIN
The document provides information on the structural tectonics and petroleum system of the Krishna Godavari Basin located in India. It discusses the formation of sedimentary basins through tectonic processes. The Krishna Godavari Basin is described as a proven oil-producing basin located along India's eastern coast. It has a thick sedimentary fill up to 5 km deposited over multiple cycles from the Late Carboniferous to the Pleistocene. The basin experienced rifting and subsidence resulting in a horst-graben system filled with sediments. It contains four petroleum systems ranging from Pre-Trappean to Post-Trappean, with source rocks including the Kommugudem Formation and reservoirs
Developing Conceptual Aquifer Geometry, Structural Geological Control and Pos...iosrjce
IOSR Journal of Applied Geology and Geophysics (IOSR-JAGG) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of Applied Geology and Geophysics. The journal welcomes publications of high quality papers on theoretical developments and practical applications in Applied Geology and Geophysics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
The Bastar Craton in central India covers an area of 130,000 square km and contains several important lithotectonic units from over 3 billion years ago. It is bounded by graben structures and mobile belts. The oldest unit is the Sukma Group dating to 3000 million years ago consisting of gneisses and iron formations. Younger granulite belts and sedimentary sequences include the Amgaon Group, Bengpal Group, and Sakoli Group indicating deposition between 2500-2600 million years ago. The Kotri-Dongargarh orogen contains the Bailadila iron formations and associated volcanic sequences like the Nandgaon Group dating to 2300 million years ago.
The document summarizes observations from a 4-day field trip by students to study the geology of the Salt Range in Pakistan. On the first day in the Eastern Salt Range, students observed and described rock formations from the Cambrian period, including the Khewra Sandstone, Kussak Formation, and Jutana Dolomite. Key observations included sedimentary structures like ripple marks, cross-bedding, and bioturbation traces. Dip and strike measurements were also recorded from various locations.
The document summarizes the tectonic framework of India in 3 broad divisions - Peninsular India, Extra-Peninsular India, and the Indo-Gangetic Plain. Peninsular India comprises the Indian shield and its sedimentary basins, and is further divided into the shield areas, mobile belts, and Proterozoic sedimentary basins. Extra-Peninsular India includes the Himalayan mountain ranges, divided into the Lesser Himalayan zone, Central Crystalline zone, and Tethyan zone. The Indo-Gangetic Plain is a deep crustal trough in northern India filled with Quaternary sediments.
Regional Tectonic Features, Processes and elements.Rukaia Aktar
The presentation mainly focus on the Bengal basin. It's features, tectonic processes and the elements of provinces of the basins. And also have the information of today's active tectonic and neotectonics.
A review of Shale gas potentiality in Bangladesh. Md. Yousuf GaziMd. Yousuf Gazi
1) The document reviews the potential for shale gas in Bangladesh by analyzing geological data from existing wells and literature.
2) It finds that shale intervals over 20m thick may exist in some tertiary formations, but they reach maturity at depths over 5000m, making extraction uneconomic.
3) Thin shale sequences in the Gondwana basin have reasonable maturity as well, but total organic carbon levels are generally too low in Bangladesh's geology to support commercial shale gas production based on current data and technology.
A report on wireline log interpretation with emphasis on hydrocarbon of Salda...Shahadat Saimon
The report focuses on wireline log interpretation of the Saldanadi structure, Bangladesh. Available data includes Gamma ray log, SP log, Density log, Neutron log and Resistivity log based on which lithology and hydrocarbon potentiality of the gas field is evaluated.
This document summarizes information about the Eastern Dharwar Craton (EDC) region of India. The EDC covers around 450,000 square kilometers and contains several greenstone belts formed from volcanic and sedimentary rocks. It is bounded by mobile belts and separated from the Western Dharwar Craton by the Chitradurga Shear Zone. The EDC contains older gneissic basement rocks overlain by the Warangal Group and greenstone belts of the Dharwar Supergroup, along with the large Closepet Granite intrusion and regions metamorphosed to amphibolite and granulite facies.
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Tectonics of bengal basin or Bangladesh
1. TECTONICS OF BENGAL BASIN
Overview
TECTONIC SET UP OF BENGAL BASIN
TECTONIC MAP OF BENGAL BASIN
DEVELOPMENT OF BENGAL BASIN
TECTONIC ELEMENTS OF BENGAL BASIN
2. The first tectonic map of the then East Pakistan was prepared in
1964. Concise characteristics of basic tectonic elements of the then
East Pakistan and its neighbouring areas were prepared in 1965 while
the major tectonic features of the then East Pakistan were compiled
in 1966. Tectonic map of Assam was published in 1964 and the
tectonic classification of Bangladesh was made in 1972.
On the other hand tectonic framework and oil and gas prospects of
Bangladesh were published in 1978. The tectonic map of Bangladesh-
past and present was introduced in 1983. It is essential to have a
clear conception about the tectonic framework of Bengal
Basin/Bangladesh in order to evaluate the prospect of MINERAL
RESOURCES including oil and NATURAL GAS.
TECTONICS OF BENGAL BASIN/Bangladesh
3. The Bengal basin occupies most of Bangladesh and West Bengal
subsurface. The extent of the basin is indirectly indicated by the hills
surrounding it. To the south the basin is open to the Bay of Bengal,
where it passes to the Bengal deep-sea Fan. It slopes south from its
head at latitude 200 north to 100 south.
The Bengal deep-sea fan is almost 3000km long and 1000km wide
with a thickness of more than 12 km of sediments. Sediments from
delta are funneled south through the “Swatch of No Ground” (submrine
canyon), to become spread out on the fan by turbidity currents.
Shield areas are exposed on sides of the Bengal basin with dis-
appearance below a blanket of alluvium within the basin. The
Precambrian shields are mainly constituted of gneisses and meta-
sediments and local granites. The Shillong Plateau and the
Precambrian shield of Bihar and West Bengal are separated from each
other by the Garo-Rajmahal Gap which is 200km wide and controls the
big bends of Ganges and Brahmaputra rivers.
The Rajmahal and Garo hilla are connected by a submerged basement
ridge (Rangpur saddle) at a depth of 200m.
4. Map showing major tectonic
elements in and around the
Bengal basin. Hinge zone
demarcates the deeper basin
from the Indian Platform area.
Right-lateral N–S faults (e.g.,
Kaladan fault) are in the east. The
Dauki fault separates the Sylhet
trough from the uplifted Shillong
Plateau at the north
5. Bangladesh is divided into two
major tectonic units:
i) Stable Pre-Cambrian
Platform/Shelf in the
northwest, and
ii) Geosynclinal basin in the
southeast.
iii) A third unit, a narrow
northeast-southwest
trending zone called the
hinge zone separates the
above two units almost
through the middle of the
country. This hinge zone
is currently known as
palaeo-continental slope.
6. Stable Pre-Cambrian Platform : Stable Pre-Cambrian Platform also refers to as
the stable shelf of the BENGAL BASIN. It is the part of the basin that lies on the west
and northwest of the line joining Calcutta and MYMENSINGH known as Calcutta-
Mymensingh gravity high, which represents the hinge zone of the basin or the
basin ward extension of the stable shelf. The stable shelf is divided into three
major zones : i) Dinajpur slope, ii) Rangpur Saddle and iii) Bogra slope.
The stable shelf is composed of continental crust overlain by Cretaceous (144 to 66
million years ago) to Recent sediments. However, in isolated basins on the stable
shelf, there is Permo-Carboniferous (360 million years to 245 million years ago)
sediments with considerable amount of COAL.
The thickness of sedimentary column on the stable shelf of Bengal Basin varies
from less then 200m to 8,000m.
A large part of the basin is covered by Sylhet limestone of Eocene age (58 million
years to 37 million years ago) and act as a marker horizon to define the basin ward
extent of the stable shelf.
In Bangladesh part coal, LIMESTONE and HARDROCK are considered to be major
mineral resources found on the shelf. However, there are evidences that precious
metal and base metal of Indian shield may also be present.
TECTONIC ELEMENTS
7. The tectonic framework of
Bangladesh can be divided into two
main elements: the Indian platform
comprising the north western part
and the Bengal foredeep representing
the thick sedimentary column forming
geosynclinal area in the south east.
These two elements are separated by
a flexure zone named as “Calcutta-
Mymenshing hinge zone”. Further
the Bengal foredeep is divided into
two parts the folded flank in the east
and platform flanks on the west
which is demarcated by “Barisal high”.
The platform flanks includes Sylhet
trough, Faridpur trough, Hatiya
trough and the Madhupur high
structures. The deepest part of Bengal
Basin is the Patuakhali trough (Figure
7).
8. Rangpur Saddle:
It represents Indian Platform and connects the Indian Shield with the SHILLONG
MASSIF and the Mikir Hills. Shillong Massif is a large thrust block of the Indian Shield.
In Rangpur Saddle the basement is the most uplifted and is covered with thin
sedimentary deposits. In Madhyapara area of DINAJPUR the basement is only 130m
deep from the ground surface and is overlain by Dupi Tila Sandstone and Madhupur
Clay of Plio-Pliestocene age.
Rangpur Saddle can be divided into 3 parts- Rangpur Saddle, Northern Slope of
Rangpur Saddle and Southern Slope of Rangpur Saddle. It is evident from seismic
data acquired out by OGDC (Oil and Gas Development Corporation) during 63-64 in
Rangpur-Dinajpur districts that both the northern and the southern slopes of
Rangpur Saddle are quite gentle. The basement plunges gently from Madhyapara
towards the southeast upto the Hinge Zone, which is known as the Southern Slope
of Rangpur Saddle. The tentative boundary of the Rangpur Saddle with the
northern and the southern slopes has been marked at approximately 700m contour
line on the basement. It separates the Bengal Foredeep and the Himalayan
Foredeep.
TECTONIC ELEMENTS
9. Dinajpur Slope: The Northern Slope of Rangpur Saddle also known as Dinajpur Slope,
occupies the north western part of Rangpur-Dinajpur districts and gently slopes towards
the Sub-Himalayan Foredeep with dips 3-4° which sharply increases in Tetulia area. The
only well drilled in 1988 located on the north-western most tip of Bangladesh at SALBANHAT
by Shell for oil and gas exploration to probe a carbonate reef ended in basement with
depth 2518m penetrating the Mio-Pliocene sequence without encountering Eocene
Limestone. The nature of junction between the Dinajpur Slope and the Sub-Himalayan
Foredeep is not clear.
Bogra Slope/Shelf: represents the southern slope of Rangpur Saddle which is a
regional monocline plunging towards southeast gently to Hinge Zone. This zone marks the
transition between the Rangpur Saddle and the Bengal Foredeep from depositional as
well as structural point of view. The width of Bogra Shelf varies from 60-125 km up to the
Hinge Zone and the thickness of the sedimentary sequence increases towards the
southeast. Stanvac Oil Company (SVOC) carried out aeromagnetic and seismic surveys in
the mid-fifties followed by two wells at Kuchma and BOGRA. Seismic contours on top of
Eocene Limestone (Bogra limestone) show regional dip of 2-3° besides revealing a
number of NE-SW trending faults of which BOGRA FAULT is the most prominent. The
attitude of Sylhet Limestone most possibly reflects the surface of the Archean Basement.
There is no closed anticlinal fold in this tectonic zone. The Bogra fault did not provide the
seal to the structural trends at Kuchma and Bogra for accumulation of commercial
HYDROCARBONs.
TECTONIC ELEMENTS
10. Calcutta-Mymensingh Gravity High: It reflects a tectonic element known as
Hinge Zone and more recently as palaeo-continental slope in the framework of
Bangladesh.
The Hinge Zone is a narrow strip of about 25 km wide complex flexure zone, which
separates the Bengal Foredeep from the shelf zone. It trends approximately N 30° E
along the Calcutta-Pabna-Mymensingh gravity high and extends upto the western tip
of Dauki fault. This zone is characterised by the sharp change in the dip of the
basement rocks associated with deep-seated displacements in faults and is reflected
on the gravity and magnetic anomalies. The Eocene limestone dips at about 200 in
this zone as compared to 2-30 in the shelf zone. The seismic interpretation shows that
the depth of the Sylhet Limestone - a strong seismic reflector - increases from 4000m
to 9000m within a narrow zone of 25-km.
Hinge Zone is connected with Bengal Foredeep by deep basement faults that
probably started with the break up of Gondwanaland. Since then they have been
repeatedly reactivated. In the northeast of Bangladesh the Hinge Zone turns to the
east and seems to be connected with the Dauki Fault, probably by a series of east-
west trending faults.
TECTONIC ELEMENTS
11. Geosynclinal Basin the geosynclinal basin in the southeast is characterised by the
huge thickness (maximum of about 20 km near the basin centre) of clastic sedimentary
rocks, mostly sandstone and shale of Tertiary age. It occupies the greater Dhaka-Faridpur-
Noakhali-Sylhet-Comilla-Chittagong areas. The huge thickness of sediments in the basin is a
result of tectonic mobility or instability of the areas causing rapid subsidence and
sedimentation in a relatively short span of geologic time. The geosynclinal basin is
subdivided into two parts i.e fold belt in the east and a foredeep to the west.
Bengal Foredeep occupies the vast area between Hinge Line and Arakan Yoma Folded
System and plays the most important role in the tectonic history of Bengal Basin.
Tectonically, Bengal Foredeep can be divided into two major regions- (a) Western Platform
Flank and (b) Eastern Folded Flank. The Western Platform flank is further subdivided into (a)
Faridpur Trough (b) Barisal-Chandpur High (c) Hatiya Trough (d) Madhupur High and (e)
Sylhet Trough.
Faridpur Trough situated adjacent to Hinge Zone is characterised by a general gravity
low with development of Neogene sequence. Sylhet Limestone is 6500 m deep in area
south of the confluence of the PADMA and the JAMUNA. Chalna and BAGERHAT are the two
notable structural highs of very low amplitude.
12. Hatiya Trough represents the deepest trough of Bengal Basin, which received highest
accumulation of clastic sediments. The axis of Bengal Foredeep runs through the apex of
Hatiya Trough. Shahbazpur (BHOLA), Kutubdia, Sangu and a large number offshore structures
are located here, of which Sangu is under production while Shahbazpur and Kutubdia are
awaiting development.
Madhupur High is represented by Pleistocene terrace of Madhupur Garh separates Faridpur
Trough from the Sylhet Trough (SURMA BASIN). Here, the basement is relatively uplifted as
evident from gravity and aeromagnetic data. Morphological studies reveal a pronounced
recent morphological upheaval east of Madhupur. Besides, Nagarpur dome, south of TANGAIL
and Nandina high showed that these are portions in the basement without deforming the
sedimentary sequence overlying these features.
Madhupur or Mymensingh High: the area represents an undulated TOPOGRAPHY slightly
elevated from the adjacent active FLOODPLAIN. At MADHUPUR, tectonic disturbances can easily
be observed where Dupi Tila sand is exposed under the Madhupur Formation.
Most of the authors believe that the MADHUPUR TRACT represents a tectonically uplifted
surface. A few also believe that the area was uplifted in very recent time and referred to the
EARTHQUAKE of 1762 as the Madhupur tract occurs along the axis of the belt of 'Volcano
action', extends in a north-western direction through CHITTAGONG and DHAKA. They
considered numerous low lakes in the Sylhet basin to be caused by SUBSIDENCE compensatory
to the elevation of the Madhupur tract. According to their belief, the uplift of Madhupur
tract resulted the diversion of the BRAHMAPUTRA River.
13. Barisal-Chandpur High is interpreted as a gravity and magnetic anomaly caused
by a magmatic body at great depth. This zone is located between Faridpur
trough and Hatiya trough of the Bengal Foredeep. The width of the zone is
about 60 km and apparently corresponds to an uplift of the sedimentary cover.
A number of gravity anomalies are spread over this zone. A paleo-high
stretching from Barisal-Chandpur High in the NE direction has been presumed
and the ridge was interpreted to turn south of Barisal-Chandpur High in north-
south direction merging with the Ninety east ridge. There is no definite
evidence for existence of such a ridge dividing the Bengal Foredeep into two
parts. PATHARGHATA, MULADI, CHANDPUR, LAKSHMIPUR [Laksmipur], MUNSHIGANJ,
Kamta and DAUDKANDI are the main anticlinal structures of this zone. Muladi
wells failed to yield positive result in respect of commercial accumulation of
HYDROCARBONs due to lack of northern closure. This zone has not been
sufficiently investigated by seismic surveys.
14. Sylhet Trough: Indian Platform bounds the trough from the west while it is
open in the southwest to the main part of Bengal Basin. It is an oval shaped
trough about 130 km long and 60 km wide. Sub-meridional trending anticlinal
folds of Chittagong-Tripura Folded Belt gradually plunge northward to the
Sylhet Trough. In cross-section the Sylhet Trough is sharply asymmetrical with
comparatively gentle southern and steep faulted northern slope.
Sylhet Trough is situated on the southern side of the Shillong Massif and
corresponds to the vast low lands of Surma Valley with numerous swamps
(haors) where absolute elevation marks even below the sea level. It is a sub-
basin of the Bengal Foredeep in the northeastern part of Bangladesh and is
characterised by a very pronounced, vast, closed negative gravity anomaly up
to 84 mgl (Milligal). Shillong Massif forms the northern boundary of Sylhet
Trough while the great Dauki Fault separates the trough from the Massif. The
Trough is bounded on the east and southeast by the sub-meridional trending
folded belt of Assam and Tripura as the frontal deformation zone of Indo-
Burman Ranges.
15. Dauki Fault with 5 km wide fault zone forms the contact between Shillong Massif
and Sylhet Trough. The evolution of Sylhet Trough includes (i) a passive
continental margin (Pre-Oligocene) to (ii) a foreland basin linked to the Indo-
Burman Ranges (Oligocene and Miolene) to (iii) a foreland basin linked to south-
directed over thrusting of Shillong Plateau (Pliocene-Holocene). The anticlinal
folds of Habiganj, Rashidpur, Bibiana, Maulvi Bazar, Katalkandi, Fenchuganj,
Harargaj, Patharia, Beani Bazar (Mama Bhagna) and Kailas Tila, which occupy the
southern rim of Sylhet Trough have sub-meridional trend in contrast to sub-
latitudinal trending Chhatak, Jalalabad, Sylhet, Dupi Tila and Jatinga structures.
These two structural trends form a syntaxial pattern at the northeastern tip of
Sylhet Trough. The Neogene sediments have excellent development in Sylhet
Trough while the Paleogenes are at greater depths.
Sylhet Trough is the most prospective petroliferous province of Bangladesh with
10 gas fields (Chhatak, Jalalabad, Sylhet, Kailas Tila, Beani Bazar, Fenchuganj,
Rashidpur, Maulvi Bazar, Bibiana and Habiganj) of which Jalalabad, Sylhet, Kailas
Tila, Rashidpur and Habiganj are producing now about 1000 million cubic feet per
day (MMCFD) for generation of power, manufacture of FERTILISER besides meeting
the industrial, commercial and domestic needs to a great extent thus contributing
immensely to the economic development of Bangladesh.
16. Folded Belt represents the most prominent tectonic element of Bengal Foredeep
with general sub-meridional trending hills parallel to the Arakan Yoma Folded
System. Folded belt extends within Bangladesh for 450 km (N-S) and about 150 km
wide covering an area of 35,000 sq km of on-shore area. A large number of narrow,
elongated N-S trending folds of the eastern part of Bangladesh (Sylhet and
Chittagong Divisions), Tripura, southern part of Assam, Mizoram and Myanmar
territory adjacent to S-E of the Chittagong Hill Tracts occupy the Folded Belt west
of the Arakan Yoma Folded System. The folds are characterised by ridge forming,
box-like in cross section, high amplitude with variable width and lie en-echelon
with the adjacent structures. The elevation of these elongated anticlinal folds in
Bangladesh ranges from 100 -1,000m. Some of the structures are faulted and
thrusted and the intensity of folding increases gradually from west to east.
Consequently, the structures of the eastern part are tightly folded, faulted and
thrusted with narrower synclines between them.
17. The Folded Belt is sub-divided into two tectonic zones- Western Zone and Eastern Zone
according to the intensity of folding and other structural features. Western Zone consists of
relatively simpler GEOLOGICAL STRUCTURES like Beanibazar (Mama Bhagna), Kailas Tila,
Fenchuganj, Kathalkandi, Maulvi Bazar, Rashidpur, Habiganj, Titas, Rokhia (Saldanadi),
Lalmai, Trichna, Agartala, Lambusara, Gojalia, Feni, Semutang, Halda, Lambaghona,
Maheshkhali, Patiya, Inani, St Martin besides the moderately tight folded anticlines like
Bachia, Langtrai, Barmura, Atharamura, Dhumbura, Tulamura, Changotang, Sardeng,
Gobamura, Sitapahar, Bandarban, Matamuhari, Olah Taung, Dakhin Nila etc and Mayu,
Pingna and Sin in Myanmar.
The Eastern Zone includes Patharia, Harargaj, Chargola, Kanchanpur, Machlithum, Sarkhan,
Langai, Badarpur, Chatrachura, Masimpur, Rengte, Bhuban, Bhairabi, Hatch Hak, Sentet,
Zanlawn, Zabwak, Maul Vawm, Jampai, Bhuachari, Shishak, Kasalang, Barkal, Utanchatra,
Belasari, Gilasari, Mowdok, Langsen, Thuamphui, Maurawap, Phalphang and Kaletwa.
(Dashed structures are in Bangladesh rest in Assam, Tripura and Mizoram of India).
The Western Zone is the most important and prospective oil and gas province of Bangladesh
with 12 fields from north to south eg Kailas Tila, Beanibazar, Fenchuganj, Maulvi Bazar,
Rashidpur, Bibiana, Habiganj, Titas, Bakhrabad, Rokhia, Feni and Semutang.
TECTONIC ELEMENTS Contd