I am an independent researcher in geoscience and engineering geology fields. Willing to collaboration with researchers working on Asia geoscience and engineering geology for Tunnelling and Geo hazards. Address: Singapore
is a conspicuous dormant volcano, which lies on the volcanic island arc (NS-trending central volc... more is a conspicuous dormant volcano, which lies on the volcanic island arc (NS-trending central volcanic line) through the Central Myanmar Basin tectonically. The rheology of lava flows is determined by the phenocryst distribution in the andesitic rocks of Mount Popa, Myanmar. Particularly, the andesitic rock units are differentiated as V1-flow andesite, Nagale-Legyingon plateau andesite, Popa plateau andesite, V3-flow andesite, and V4-flow andesite. The different flow units are megascopic ally very similar in color and texture to porphyritic andesite or augite andesite but different in grain size, and the amount of phenocryst. The phenocryst distribution is graphically correlated with the Newtonian and non-Newtonian flow to interpret the rheology of lava flow during the Pliocene-Holocene eruption of the Mount Popa volcano. A new method which is simplest and practiced to identify the porphyritic andesitic rocks or lava flows not only for the stratigraphy but also the rheology.
The Eastern Highlands of Myanmar are characterized by Precambrian to Mesozoic rock formations, wi... more The Eastern Highlands of Myanmar are characterized by Precambrian to Mesozoic rock formations, with Carboniferous-Permian sequences prominently present in the Shan Scarp and Shan Plateau zones. These sequences are particularly concentrated in the western margin of the Sibumasu Block. Although Permian sequences are abundant in this region, they are complicated by geological faults. Consequently, a lithostratigraphic study was conducted to establish correlations across an extensive area spanning 1200 km from Mandalay City in the north to Kawthaung City in the south and 250 km wide, bordered by the Sagaing Fault to the west and Inle Lake to the east. The Permian sequences can be categorized into lower siliciclastic units and upper carbonate units. These siliciclastic units encompass the Mergui Group, locally referred to as the Lebyin Group, Mawchi Series, Taungnyo Group, and Mergui Group, as well as the Yinyaw Formation. Additionally, there is a carbonate unit known as the Moulmein Formation in the Thaton, Hpa-an, and Mawlamyine areas, and the Tenasserim Formation in the Myeik and Bokepyin areas within the Shan Scarp zone. In the late Lower Permian sequences, the Mwedaw Beds are exclusively found in the Linwe area. However, the Thitsipin Formation, which is an equivalent of the Moulmein Formation, and the Nwabangyi Formation are also exposed in the Shan Plateau zone. Lower Carboniferous sequences, such as the Loikaw Beds, are sporadically visible in the Loikaw area but are overlain by the Thitsipin Formation. This study elucidates the presence of a diamictite unit (Mergui Group) and its associated units (Yinyaw and Thitsipin/Moulmein formations) in the geo-structurally complex zones of the Shan Plateau and Shan Scarp through lateral lithostratigraphic correlation, shedding light on the Carboniferous-Permian period at the western margin of the Sibumasu Block.
The Kabaw Fault is a north-south trending arcuate suture zone formed between the accretionary pri... more The Kabaw Fault is a north-south trending arcuate suture zone formed between the accretionary prism of the Indo-Myanmar Ranges (IMR), and the Central Myanmar Basin (CMB). The lineament of the Kabaw Fault is defined as a stratigraphic contact zone between flysch sediments of the IMR and molassic sediments of the CMB along the eastern base of the IMR. The accretionary prism of IMR was initially formed as a single wedge (pro-wedge) during Triassic, however, the forceful subduction of the Indian Plate resulted in the formation of an open wedge (double-sided wedge) during the Cretaceous. The double-sided wedge of the accretionary prism of IMR is revealed by the structural deformation pattern of the molassic sediments and the Triassic flysch exposures in the fore-arc basin of CMB, however, the eastern part of the wedge is buried under the fore-arc basin. At the eastern base of IMR, the ophiolite occurrences are close to the Kabaw Fault except in the Kabaw Valley where the ophiolites are associated with the Jurassic sedimentary rock units. The Kabaw Valley is generally occurred as a north-south elongated lowland basin, positioned along the western part of the Kabaw Fault. The east-dipping geometry of the Kabaw Fault is manifested by the evidence of east-verging synclinal folds of the fore-arc basin in the CMB, and the east-verging folding is due to slip up on the slope of the retro-wedge. The dextral strike-slip movement of the Kabaw Fault is displayed by the shifting of mud volcanoes in the Pyay to Kalaywa region and the two-phase folding and deformation within the Chindwin sub-basin and the Minbu-Salin sub-basin. The present study proves not only the Kabaw Fault as an east-dipping reverse fault with structural evidence, but also reveals the double-sided wedge system of the IMR accretionary prism.
This study provides the syn and post deformation of Neogene siliciclastic sequences of Arakan Cos... more This study provides the syn and post deformation of Neogene siliciclastic sequences of Arakan Costal Ranges in Western Myanmar that allows structural and kinematic interpre-tation of oblique subduction and collision history. The growth of these folds and faults and associated uplifting which were resulted by tectonic evolution between Burma Plate was wedged in the subduction zone and dragged mechanically toward the north with the Indian Plate between internal N-S trending right-lateral shearing and external E-W shortening.
Bengal-Arakan Neogene basin is one of the representative clastic basins formed in the frontal par... more Bengal-Arakan Neogene basin is one of the representative clastic basins formed in the frontal part of the Himalayan orogenic belt since late Cenozoic (Kyi Khin et al., 2014, 2017). The basin occupies the eastern part of Paleo-Bengal basin, the biggest basin of the world in Cenozoic. It is located at the unique tectonic setting; a juncture of the collision zone between the Indian and Asian continents to the north and the subduction zone between the Indian Plate and Myanmar Plate to the east. The purpose of the study is to shed some light on the sedimentation in the distal foreland basin of the Himalaya-Bengal System, related with control on timing and distribution of erosional fluxes derived from the uplifted Himalayas since Early Miocene. Chemical weathering strongly affects the major-element geochemistry and mineralogy of siliciclastic sediments. The predicted weathering trend line intersects the feldspar join at the point that shows the proportion of plagioclase and K-feldspar of the fresh rock between granodiorite and granite composition. Moreover, lower Middle Miocene (MM1) samples fall at the lower end of the line (near CN apex), and show a lower Chemical Index of Alteration (CIA) than the other units. This evidence shows the lower intensity of chemical weathering in the lower Middle Miocene than in the Lower Miocene samples. The A-CN-K triangle plots and CIA values suggest granitic and granodioritic composition in most sandstones and shales. Minor enrichment of CN in the middle Miocene sandstones may indicate a relationship of marine transgression that deposited thick gray shale on the Lower Miocene (Laung Formation) as subsequent burial. The presentation will focus on the results of an integrated study of sequence stratigraphy of the Miocene sediments and provenance studies based on the petrography and chemical composition of sandstones and shales, in order to interpret the weathering episode and relationship between tectonic denudation of Himalaya orogenic belts and reciprocal sedimentation related with foreland thrusting of Himalaya-Bengal system. References Kyi Khin, Sakai, T., and Khin Zaw 2014. Neogene syn-tectonic sedimentation in the eastern margin of Arakan-Bengal basins, and its implications for the Indian ering episode and relationship betw Gondwana Research, 26, 89a Res Kyi Khin, Sakai, T., and Khin Zaw 2017. Chapter 5. Arakan Coastal Ranges in western Myanmar, geology and provenance of Neogene siliciclastic sequences: implications for the tectonic evolution of the Himalayath foreland thrusting of Himalaya-Khin Zaw & Crow, M.J. (eds.) Myanmar: Geology, Resources and Tectonics. Geological Society, London, Memoirs, 48, 81mar: Geology, Resources and Tectoni
This compilation was aimed to record for rare geological outcrops which were gradually diminished... more This compilation was aimed to record for rare geological outcrops which were gradually diminished by infrastructural and construction projects. Sharing information among fellow geologists working in Singapore and abroad. Wish for more new findings, contributions and researches on Geology of Singapore, in future.
The Indo-Myanmar Ranges (IMR), known as an accretionary prism, lies between the Kaladan Fault (su... more The Indo-Myanmar Ranges (IMR), known as an accretionary prism, lies between the Kaladan Fault (subduction suture) in the west and Kabaw Fault (the boundary between flysch units and molasse units) in the east is very important to interpret the paleogeographic evolution of the major continents, restoring the paleogeography and plate boundary evolution between the India Plate and West Myanmar Block. The present study explained compression along the Shillong Massif into the IMR with a conceptual model that involves 6-stages of deformation processes. The Kabaw Fault along the eastern rim of Kabaw Valley or the western border of the Kabaw Formation occurs as both an east-dipping thrust and a dextral strike-slip fault. The tectonic model proposed for the IMR is a double-wedge system, in which retro-wedge and east-dipping Kabaw Fault are interrelated to form Nappe of Triassic unit (Thanbaya Formation) with double plunging synclines of Chindwin and Minbu-Salin sub-basins. The Jurassic unit (Kyauksitchaung Formation) is newly found along the eastern base of the IMR as a lithostratigraphic unit and a window structure under the Nappe of the Triassic unit. The alignment of the Kaladan Fault is newly proposed as a suture zone revealed by the window structures of the Oligocene flysch unit under the Nappe of Neogene units on the onshore area, and localities of the mud volcanoes and structural trend of small islands at the offshore area. The formation of circular structures on the Ramree Archipelago is explained by superimposed folding with heterogenous simple shear deformation of the dome and basin structures due to the NW movement of the Broken-Block of IMR colliding with foreland basins including Chittagong-Tripura Fold Belt (CTFB) and Baronga (Boronga) Islands.
The Indo-Myanmar Ranges (IMR), known as an accretionary prism, lies between the Kaladan Fault (su... more The Indo-Myanmar Ranges (IMR), known as an accretionary prism, lies between the Kaladan Fault (subduction suture) in the west and Kabaw Fault (the boundary between flysch units and molasse units) in the east is very important to interpret the paleogeographic evolution of the major continents, restoring the paleogeography and plate boundary evolution between the India Plate and West Myanmar Block. The present study explained compression along the Shillong Massif into the IMR with a conceptual model that involves 6-stages of deformation processes. The Kabaw Fault along the eastern rim of Kabaw Valley or the western border of the Kabaw Formation occurs as both an east-dipping thrust and a dextral strike-slip fault. The tectonic model proposed for the IMR is a double-wedge system, in which retro-wedge and east-dipping Kabaw Fault are interrelated to form Nappe of Triassic unit (Thanbaya Formation) with double plunging synclines of Chindwin and Minbu-Salin sub-basins. The Jurassic unit (Kyauksitchaung Formation) is newly found along the eastern base of the IMR as a lithostratigraphic unit and a window structure under the Nappe of the Triassic unit. The alignment of the Kaladan Fault is newly proposed as a suture zone revealed by the window structures of the Oligocene flysch unit under the Nappe of Neogene units on the onshore area, and localities of the mud volcanoes and structural trend of small islands at the offshore area. The formation of circular structures on the Ramree Archipelago is explained by superimposed folding with heterogenous simple shear deformation of the dome and basin structures due to the NW movement of the Broken-Block of IMR colliding with foreland basins including Chittagong-Tripura Fold Belt (CTFB) and Baronga (Boronga) Islands.
This compilation was aimed to record for rare geological outcrops which were gradually diminished... more This compilation was aimed to record for rare geological outcrops which were gradually diminished by infrastructural and construction projects. Sharing information among fellow geologists working in Singapore and abroad. Wish for more new findings, contributions and researches on Geology of Singapore, in future.
This chapter presents an account of the Cretaceous System and its tectonic setting in Myanmar, se... more This chapter presents an account of the Cretaceous System and its tectonic setting in Myanmar, sedimentary sequences of the Bago Yoma, Central Myanmar and the fluvial architecture of the Irrawaddy Sandstone in the Salin Basin.
Termination of the eastward subduction of the Indian Plate is inferred to be latest Eocene in age... more Termination of the eastward subduction of the Indian Plate is inferred to be latest Eocene in age in the northeasternmost Assam and Myanmar regions, followed by the collision of the Indian continent with the Asia Plate. This event is typically represented by the underthrusting of the Middle and Upper Eocene Sylhet Formation, which was deposited on the western margin of India Plate, beneath the Eocene Disang Formation, while the northern margin of India collided against Eurasia and Tibet along a zone, which lies south of the Triassic-Jurassic deep-marine sediments and Yarlung ophiolite in the latest Eocene. Later movement of the Naga and Disang Thrusts to the east suggests convergence between the Burma and Indian Plates, as both moved northwards and India rotated anticlockwise after the collision. The stratigraphic records indicate that an early Oligocene emplacement of the deep-marine sedimentary sequence on the India plate, probably within 10 Ma interval age during the India-Asia collision, and moved northwards. Oblique convergence could also have resulted from possible clockwise rotation of SE Asia relative to the Indian Plate accompanying the eastward translation of South China along strike-slip faults. The deformation of western and southern Myanmar is still active today with under-thrusting related to subduction. The basement of the Indian Plate below the Indo-Myanmar Ranges is moving towards the north with respect to the rest of Asia. This study provides the syn-and post-deformation history of Neogene siliciclastic sequences of the Rakhine Coastal Ranges in western Myanmar allowing structural and kinematic interpretation of the oblique subduction and collision history. The growth of these folds and faults and associated uplift were resulted from the tectonic processes and evolution in which the Burma Plate was wedged in the subduction zone and dragged towards the north with the Indian Plate between internal N-S trending right-lateral shearing and external E-W shortening.
The Arakan Basin is one of the representative clastic basins formed in the frontal part of the Hi... more The Arakan Basin is one of the representative clastic basins formed in the frontal part of the Himalayan orogenic belt since the Late Cenozoic. Defining one of the four major sedimentary basins of Myanmar, it is geomorphologically and tectonically differentiated from the others. The study area along the westernmost edge of Myanmar is separated from the Arakan Yoma (IndoBurma Ranges) by a narrow coastal strip and is bordered by the Bay of Bengal to the west. Regional stratigraphic correlation and the geological age of the siliciclastic sequences were established, based on planktonic foraminifera zonation. Deep marine slope and shelf environments during early Miocene to middle Miocene (about 21.5 to 11 Ma) southward prograded shelf-delta environment during late Miocene to Pliocene time were determined. The early Miocene underthrusting along the Himalaya front is well documented by the forcedregressive sedimentation patterns in the slope and shelf systems, sediments of which derived fr...
is a conspicuous dormant volcano, which lies on the volcanic island arc (NS-trending central volc... more is a conspicuous dormant volcano, which lies on the volcanic island arc (NS-trending central volcanic line) through the Central Myanmar Basin tectonically. The rheology of lava flows is determined by the phenocryst distribution in the andesitic rocks of Mount Popa, Myanmar. Particularly, the andesitic rock units are differentiated as V1-flow andesite, Nagale-Legyingon plateau andesite, Popa plateau andesite, V3-flow andesite, and V4-flow andesite. The different flow units are megascopic ally very similar in color and texture to porphyritic andesite or augite andesite but different in grain size, and the amount of phenocryst. The phenocryst distribution is graphically correlated with the Newtonian and non-Newtonian flow to interpret the rheology of lava flow during the Pliocene-Holocene eruption of the Mount Popa volcano. A new method which is simplest and practiced to identify the porphyritic andesitic rocks or lava flows not only for the stratigraphy but also the rheology.
The Eastern Highlands of Myanmar are characterized by Precambrian to Mesozoic rock formations, wi... more The Eastern Highlands of Myanmar are characterized by Precambrian to Mesozoic rock formations, with Carboniferous-Permian sequences prominently present in the Shan Scarp and Shan Plateau zones. These sequences are particularly concentrated in the western margin of the Sibumasu Block. Although Permian sequences are abundant in this region, they are complicated by geological faults. Consequently, a lithostratigraphic study was conducted to establish correlations across an extensive area spanning 1200 km from Mandalay City in the north to Kawthaung City in the south and 250 km wide, bordered by the Sagaing Fault to the west and Inle Lake to the east. The Permian sequences can be categorized into lower siliciclastic units and upper carbonate units. These siliciclastic units encompass the Mergui Group, locally referred to as the Lebyin Group, Mawchi Series, Taungnyo Group, and Mergui Group, as well as the Yinyaw Formation. Additionally, there is a carbonate unit known as the Moulmein Formation in the Thaton, Hpa-an, and Mawlamyine areas, and the Tenasserim Formation in the Myeik and Bokepyin areas within the Shan Scarp zone. In the late Lower Permian sequences, the Mwedaw Beds are exclusively found in the Linwe area. However, the Thitsipin Formation, which is an equivalent of the Moulmein Formation, and the Nwabangyi Formation are also exposed in the Shan Plateau zone. Lower Carboniferous sequences, such as the Loikaw Beds, are sporadically visible in the Loikaw area but are overlain by the Thitsipin Formation. This study elucidates the presence of a diamictite unit (Mergui Group) and its associated units (Yinyaw and Thitsipin/Moulmein formations) in the geo-structurally complex zones of the Shan Plateau and Shan Scarp through lateral lithostratigraphic correlation, shedding light on the Carboniferous-Permian period at the western margin of the Sibumasu Block.
The Kabaw Fault is a north-south trending arcuate suture zone formed between the accretionary pri... more The Kabaw Fault is a north-south trending arcuate suture zone formed between the accretionary prism of the Indo-Myanmar Ranges (IMR), and the Central Myanmar Basin (CMB). The lineament of the Kabaw Fault is defined as a stratigraphic contact zone between flysch sediments of the IMR and molassic sediments of the CMB along the eastern base of the IMR. The accretionary prism of IMR was initially formed as a single wedge (pro-wedge) during Triassic, however, the forceful subduction of the Indian Plate resulted in the formation of an open wedge (double-sided wedge) during the Cretaceous. The double-sided wedge of the accretionary prism of IMR is revealed by the structural deformation pattern of the molassic sediments and the Triassic flysch exposures in the fore-arc basin of CMB, however, the eastern part of the wedge is buried under the fore-arc basin. At the eastern base of IMR, the ophiolite occurrences are close to the Kabaw Fault except in the Kabaw Valley where the ophiolites are associated with the Jurassic sedimentary rock units. The Kabaw Valley is generally occurred as a north-south elongated lowland basin, positioned along the western part of the Kabaw Fault. The east-dipping geometry of the Kabaw Fault is manifested by the evidence of east-verging synclinal folds of the fore-arc basin in the CMB, and the east-verging folding is due to slip up on the slope of the retro-wedge. The dextral strike-slip movement of the Kabaw Fault is displayed by the shifting of mud volcanoes in the Pyay to Kalaywa region and the two-phase folding and deformation within the Chindwin sub-basin and the Minbu-Salin sub-basin. The present study proves not only the Kabaw Fault as an east-dipping reverse fault with structural evidence, but also reveals the double-sided wedge system of the IMR accretionary prism.
This study provides the syn and post deformation of Neogene siliciclastic sequences of Arakan Cos... more This study provides the syn and post deformation of Neogene siliciclastic sequences of Arakan Costal Ranges in Western Myanmar that allows structural and kinematic interpre-tation of oblique subduction and collision history. The growth of these folds and faults and associated uplifting which were resulted by tectonic evolution between Burma Plate was wedged in the subduction zone and dragged mechanically toward the north with the Indian Plate between internal N-S trending right-lateral shearing and external E-W shortening.
Bengal-Arakan Neogene basin is one of the representative clastic basins formed in the frontal par... more Bengal-Arakan Neogene basin is one of the representative clastic basins formed in the frontal part of the Himalayan orogenic belt since late Cenozoic (Kyi Khin et al., 2014, 2017). The basin occupies the eastern part of Paleo-Bengal basin, the biggest basin of the world in Cenozoic. It is located at the unique tectonic setting; a juncture of the collision zone between the Indian and Asian continents to the north and the subduction zone between the Indian Plate and Myanmar Plate to the east. The purpose of the study is to shed some light on the sedimentation in the distal foreland basin of the Himalaya-Bengal System, related with control on timing and distribution of erosional fluxes derived from the uplifted Himalayas since Early Miocene. Chemical weathering strongly affects the major-element geochemistry and mineralogy of siliciclastic sediments. The predicted weathering trend line intersects the feldspar join at the point that shows the proportion of plagioclase and K-feldspar of the fresh rock between granodiorite and granite composition. Moreover, lower Middle Miocene (MM1) samples fall at the lower end of the line (near CN apex), and show a lower Chemical Index of Alteration (CIA) than the other units. This evidence shows the lower intensity of chemical weathering in the lower Middle Miocene than in the Lower Miocene samples. The A-CN-K triangle plots and CIA values suggest granitic and granodioritic composition in most sandstones and shales. Minor enrichment of CN in the middle Miocene sandstones may indicate a relationship of marine transgression that deposited thick gray shale on the Lower Miocene (Laung Formation) as subsequent burial. The presentation will focus on the results of an integrated study of sequence stratigraphy of the Miocene sediments and provenance studies based on the petrography and chemical composition of sandstones and shales, in order to interpret the weathering episode and relationship between tectonic denudation of Himalaya orogenic belts and reciprocal sedimentation related with foreland thrusting of Himalaya-Bengal system. References Kyi Khin, Sakai, T., and Khin Zaw 2014. Neogene syn-tectonic sedimentation in the eastern margin of Arakan-Bengal basins, and its implications for the Indian ering episode and relationship betw Gondwana Research, 26, 89a Res Kyi Khin, Sakai, T., and Khin Zaw 2017. Chapter 5. Arakan Coastal Ranges in western Myanmar, geology and provenance of Neogene siliciclastic sequences: implications for the tectonic evolution of the Himalayath foreland thrusting of Himalaya-Khin Zaw & Crow, M.J. (eds.) Myanmar: Geology, Resources and Tectonics. Geological Society, London, Memoirs, 48, 81mar: Geology, Resources and Tectoni
This compilation was aimed to record for rare geological outcrops which were gradually diminished... more This compilation was aimed to record for rare geological outcrops which were gradually diminished by infrastructural and construction projects. Sharing information among fellow geologists working in Singapore and abroad. Wish for more new findings, contributions and researches on Geology of Singapore, in future.
The Indo-Myanmar Ranges (IMR), known as an accretionary prism, lies between the Kaladan Fault (su... more The Indo-Myanmar Ranges (IMR), known as an accretionary prism, lies between the Kaladan Fault (subduction suture) in the west and Kabaw Fault (the boundary between flysch units and molasse units) in the east is very important to interpret the paleogeographic evolution of the major continents, restoring the paleogeography and plate boundary evolution between the India Plate and West Myanmar Block. The present study explained compression along the Shillong Massif into the IMR with a conceptual model that involves 6-stages of deformation processes. The Kabaw Fault along the eastern rim of Kabaw Valley or the western border of the Kabaw Formation occurs as both an east-dipping thrust and a dextral strike-slip fault. The tectonic model proposed for the IMR is a double-wedge system, in which retro-wedge and east-dipping Kabaw Fault are interrelated to form Nappe of Triassic unit (Thanbaya Formation) with double plunging synclines of Chindwin and Minbu-Salin sub-basins. The Jurassic unit (Kyauksitchaung Formation) is newly found along the eastern base of the IMR as a lithostratigraphic unit and a window structure under the Nappe of the Triassic unit. The alignment of the Kaladan Fault is newly proposed as a suture zone revealed by the window structures of the Oligocene flysch unit under the Nappe of Neogene units on the onshore area, and localities of the mud volcanoes and structural trend of small islands at the offshore area. The formation of circular structures on the Ramree Archipelago is explained by superimposed folding with heterogenous simple shear deformation of the dome and basin structures due to the NW movement of the Broken-Block of IMR colliding with foreland basins including Chittagong-Tripura Fold Belt (CTFB) and Baronga (Boronga) Islands.
The Indo-Myanmar Ranges (IMR), known as an accretionary prism, lies between the Kaladan Fault (su... more The Indo-Myanmar Ranges (IMR), known as an accretionary prism, lies between the Kaladan Fault (subduction suture) in the west and Kabaw Fault (the boundary between flysch units and molasse units) in the east is very important to interpret the paleogeographic evolution of the major continents, restoring the paleogeography and plate boundary evolution between the India Plate and West Myanmar Block. The present study explained compression along the Shillong Massif into the IMR with a conceptual model that involves 6-stages of deformation processes. The Kabaw Fault along the eastern rim of Kabaw Valley or the western border of the Kabaw Formation occurs as both an east-dipping thrust and a dextral strike-slip fault. The tectonic model proposed for the IMR is a double-wedge system, in which retro-wedge and east-dipping Kabaw Fault are interrelated to form Nappe of Triassic unit (Thanbaya Formation) with double plunging synclines of Chindwin and Minbu-Salin sub-basins. The Jurassic unit (Kyauksitchaung Formation) is newly found along the eastern base of the IMR as a lithostratigraphic unit and a window structure under the Nappe of the Triassic unit. The alignment of the Kaladan Fault is newly proposed as a suture zone revealed by the window structures of the Oligocene flysch unit under the Nappe of Neogene units on the onshore area, and localities of the mud volcanoes and structural trend of small islands at the offshore area. The formation of circular structures on the Ramree Archipelago is explained by superimposed folding with heterogenous simple shear deformation of the dome and basin structures due to the NW movement of the Broken-Block of IMR colliding with foreland basins including Chittagong-Tripura Fold Belt (CTFB) and Baronga (Boronga) Islands.
This compilation was aimed to record for rare geological outcrops which were gradually diminished... more This compilation was aimed to record for rare geological outcrops which were gradually diminished by infrastructural and construction projects. Sharing information among fellow geologists working in Singapore and abroad. Wish for more new findings, contributions and researches on Geology of Singapore, in future.
This chapter presents an account of the Cretaceous System and its tectonic setting in Myanmar, se... more This chapter presents an account of the Cretaceous System and its tectonic setting in Myanmar, sedimentary sequences of the Bago Yoma, Central Myanmar and the fluvial architecture of the Irrawaddy Sandstone in the Salin Basin.
Termination of the eastward subduction of the Indian Plate is inferred to be latest Eocene in age... more Termination of the eastward subduction of the Indian Plate is inferred to be latest Eocene in age in the northeasternmost Assam and Myanmar regions, followed by the collision of the Indian continent with the Asia Plate. This event is typically represented by the underthrusting of the Middle and Upper Eocene Sylhet Formation, which was deposited on the western margin of India Plate, beneath the Eocene Disang Formation, while the northern margin of India collided against Eurasia and Tibet along a zone, which lies south of the Triassic-Jurassic deep-marine sediments and Yarlung ophiolite in the latest Eocene. Later movement of the Naga and Disang Thrusts to the east suggests convergence between the Burma and Indian Plates, as both moved northwards and India rotated anticlockwise after the collision. The stratigraphic records indicate that an early Oligocene emplacement of the deep-marine sedimentary sequence on the India plate, probably within 10 Ma interval age during the India-Asia collision, and moved northwards. Oblique convergence could also have resulted from possible clockwise rotation of SE Asia relative to the Indian Plate accompanying the eastward translation of South China along strike-slip faults. The deformation of western and southern Myanmar is still active today with under-thrusting related to subduction. The basement of the Indian Plate below the Indo-Myanmar Ranges is moving towards the north with respect to the rest of Asia. This study provides the syn-and post-deformation history of Neogene siliciclastic sequences of the Rakhine Coastal Ranges in western Myanmar allowing structural and kinematic interpretation of the oblique subduction and collision history. The growth of these folds and faults and associated uplift were resulted from the tectonic processes and evolution in which the Burma Plate was wedged in the subduction zone and dragged towards the north with the Indian Plate between internal N-S trending right-lateral shearing and external E-W shortening.
The Arakan Basin is one of the representative clastic basins formed in the frontal part of the Hi... more The Arakan Basin is one of the representative clastic basins formed in the frontal part of the Himalayan orogenic belt since the Late Cenozoic. Defining one of the four major sedimentary basins of Myanmar, it is geomorphologically and tectonically differentiated from the others. The study area along the westernmost edge of Myanmar is separated from the Arakan Yoma (IndoBurma Ranges) by a narrow coastal strip and is bordered by the Bay of Bengal to the west. Regional stratigraphic correlation and the geological age of the siliciclastic sequences were established, based on planktonic foraminifera zonation. Deep marine slope and shelf environments during early Miocene to middle Miocene (about 21.5 to 11 Ma) southward prograded shelf-delta environment during late Miocene to Pliocene time were determined. The early Miocene underthrusting along the Himalaya front is well documented by the forcedregressive sedimentation patterns in the slope and shelf systems, sediments of which derived fr...
Accurate muck reconciliation is very important not only in segmental tunnelling but also in pipe ... more Accurate muck reconciliation is very important not only in segmental tunnelling but also in pipe jacking operation to monitor and control the excavation volume. In slurry segmental tunnelling system, this process is done automatically and in real-time using flowmeters and density meters whereas many slurry pipe jacking sites are still relying on conventional techniques such as spoil volume measurements at the pit or the discharge tanks. However, it is often observed that suspended solids in the slurry system are unaccounted or discounted due to inadequate mass balance formulation resulting in negative excavation volume reconciliation which makes over-excavation difficult to be detected should it happens during pipe jacking drives. This paper briefly describes the formulation framework for muck reconciliation and practice implemented systemwide in the Deep Tunnel Sewerage System Phase 2 (DTSS2) Project for its link sewer pipe jacking works.
Volcanoclastic rocks of similar composition to igneous rocks are known to occur in Jurong Formati... more Volcanoclastic rocks of similar composition to igneous rocks are known to occur in Jurong Formation in Singapore. According to the new stratigraphic scheme that the Building Control Authority (BCA) is implementing, they are upgraded to a member level under Jurong Group. However, there is limited information, regarding tunnelling machine performance in these rocks as these rocks have not been extensively tunnelling through previously. Recently in Deep Tunnel Sewerage System Phase 2 (DTSS2) project, 3 of 19 DTSS2’s slurry Tunnel Boring Machines (TBMs) – namely TBM Warwick, TBM Alexandra and TBM Spooner bored through these volcanoclastic rocks in the Alexandra and Kent ridge areas for the construction of a section of South Tunnel and Southern Region Link Sewer Tunnel. The TBM drives took place at a depth of ~35 mBGL under Ayer Rajah Expressway and Alexandra Road where volcanoclastic rocks were encountered in full-face rock condition. In this paper, the performance of slurry TBM drives in the volcanoclastic rocks are summarised and reported with some key tunnelling parameters for appropriate planning of resources and equipment in future tunnelling projects in similar ground condition.
Permeation grouting work is one of the key activities in most urban deep excavation and tunnellin... more Permeation grouting work is one of the key activities in most urban deep excavation and tunnelling projects to facilitate the construction execution without any prolong disruption. Groundwater level drawdown can trigger excessive ground settlement and cause damages to building structures and subterranean services in the vicinity. Therefore, the Deep Tunnel Sewerage System Phase 2 (DTSS2) project, a major used-water infrastructure project in Singapore, prescribes criteria and guidelines for pre-permeation grouting scheme in contract specifications for implementation at the multiple deep tunnel shaft excavation sites as a construction risk mitigation measure. Within this requirement framework, various grouting schemes are proposed and implemented by builders basing mainly on seepage analyses and damage assessments. Following the extensive permeation grouting, permeability tests, pumping tests are also carried out as part of the requirement. However, there are certain sites on the project where such a grouting requirement is not mandated and subject to own assessment. This paper outlines the project requirements, implementation, and its benefits in construction risk management.
• Importance of the geological and geographical factors
• Site investigation and Monitoring
• Mi... more • Importance of the geological and geographical factors • Site investigation and Monitoring • Mitigation and regular inspection
The oblique or hyper-oblique plate convergence along the Indo-Myanmar Ranges in Southeast Asia ha... more The oblique or hyper-oblique plate convergence along the Indo-Myanmar Ranges in Southeast Asia has been extensively studied, yet its precise nature remains elusive without comprehensive geological and structural evidence. While some geophysicists have attempted to determine the obliquity of convergence between the Indian Plate and the West Myanmar Block, or measured obliquity along the Sunda Arc, they lack geological, stratigraphical and structural evidence presenting a nuanced picture. Insights from the fold studies on Baronga Island and in Tripura State reveal upright anticlinal and synclinal folds within Miocene sequences in the foreland basin. Notably, the Chindwin sub-basin and the Minbu-Salin sub-basin in the Central Myanmar Basin exhibit welldeveloped east-verging double-plunging synclines in the forearc basin. The Sunda Arc extends as a megathrust through the Bay of Bengal to the Bengal Delta, indicating large-scale slip between subducting and overriding plates. However, further analysis, including seismic sections and tectonostratigraphic studies along the Sunda Arc up to the Kaladan Fault, is necessary for a comprehensive understanding.
Deep excavations in DTSS2 Project provide large scale fresh rock exposures for geological observa... more Deep excavations in DTSS2 Project provide large scale fresh rock exposures for geological observation and interpretation which we cannot get chance to see on surface in Singapore Distribution of various types of Volcanogenic Rocks in Jurong Group which recently refined into different stratotypes by the Building and Construction Authority (BCA) Geological structure, hydrogeological and engineering geological features are properly mapped and documented it may be of interest to relate and interpret within the new Bed Rock Geological Map (BCA, 2018)
This paper briefly outlines the engineering geological properties of volcanogenic rock units in J... more This paper briefly outlines the engineering geological properties of volcanogenic rock units in Jurong Group and some construction challenges experienced in the Deep Tunnel Sewerage System Phase 2 (DTSS2) Project. There are 3 types of volcanogenic rocks identified in the project area. The texture and mineral composition of lithic fragments contained in these rocks indicate that they are strong to very strong, dense, and slightly metamorphosed Tuff, Volcanic Breccia, and Ignimbrite. The contacts between volcanogenic rocks and sedimentary sequences are also observed at mined tunnel openings, shaft excavations and tunnelling at Kent Ridge, Portsdown and Queenstown areas. Due to the nature of hard and soft alternation in sedimentary sequences, weathering depth is highly variable and shows an irregular rockhead profile in most parts of the areas. The relationship between rock mass properties, physio-mechanical properties and the construction challenges were also discussed to provide references for future projects.
The transprsession tectonic is common with oblique convergence subduction zone in the world as we... more The transprsession tectonic is common with oblique convergence subduction zone in the world as well as collision of India Plate to West Myanmar Block (WMB), especially effects on the CMB. Structural evidences of transpression are recorded in the CMB as en-echelon folding and fracturing by satellite images, field observation and 3D strain ellipsoid construction showing plane strain by pure shear upon ideal strike-slip with simple shear. Central Myanmar Basin (CMB) lies between the two major strike-slip faults: Sagaing Fault to the east and Kabaw Fault to the west. Central Volcanic Line of Myanmar emplaced along the fault zone of P-shears en-echelon array, which is situated between active dextral major faults and formed at a low angle about 15° to the shear zone boundary. Deformation processes related to India Plate movement are deduced for the period of Late Miocene and Pliocene-Pleistocene based on structural analysis in Rakhine Coastal Region, western Myanmar. During the period between the Late Miocene to the Pliocene-Pleistocene, pre-existing ophiolite zone in the Indo-Myanmar Ranges (IMR) was dissected into different zones by Sagaing Fault displacement, accompanied by the movement of WMB together with India Plate subduction. Accordance with the northward movement of WMB the Sagaing Fault displacement and group of Mud volcanoes shifting Pyay to Kalaywa areas were measured about 450 km with displacement rate 5-7 cm per annum by the 45°-50°convergent angle of India Plate collision to Eurasia Plate. Transpressional deformation of northward compression was developed in the CMB, simultaneously on the other side transtension as pull-apart basin was formed by Andaman Sea opening at the south on the Sagaing Fault. During the Miocene time, collision of India Plate and Eurasia Plate was principal cause of the deformation at northern border of the India, in which India Plate moved northwards direction and rotated anticlockwise , whereas WMB together with Sibumasu Block rotated clockwise becoming final closure of the north-easternmost Assam and Myanmar regions. During the Oligocene time, deposition of the shallow marine Barail Formation in the Bengal Basin and shallow marine to continental shelf sequences in the CMB started as twin trough. This study proposes the transpressional deformation in the CMB and related regions during the syn-and post-collision of India Plate to WMB with positional and kinematic structural interpretation.
Singapore's Deep Tunnel Sewerage System Phase 2 (DTSS2) project comprises 50 km of tunnelling wor... more Singapore's Deep Tunnel Sewerage System Phase 2 (DTSS2) project comprises 50 km of tunnelling work by 19 Tunnel Boring Machines (TBM) and another 50 km of link sewer pipe jacking work to channel used water to a new centralised water reclamation plant to be constructed at Tuas-Tuas Water Reclamation Plant (TWRP). A number of the tunnel shaft locations also include Air Jumpers (AJ), Odour Control Facilities (OCF) and hydraulic structures. Therefore, construction of DTSS2 will produce significant amount of data every day particularly from well instrumented TBMs and pipe jack machines. Since PUB recognizes the volume of data during construction, the Shaft and Tunnel Excavation Monitoring System (STEMS) is introduced in DTSS2 project to integrate all construction monitoring and tunnelling data into a common system environment. The aim is to deliver better quality and timely data with various analytics and reporting capabilities for decision making and risk management. Therefore, engineering geological data, geotechnical instrumentation data, excavation data, TBM and pipe jacking machine data, construction progress and other metadata across the project are taken into the system for processing and integrated into various user definable formats to facilitate quick review and combined analysis. The web-based and integrated nature of this centralised processed data management system also has real-time TBM monitoring capability and automatic SMS alerting feature. Hazards and risks, which are always linked to ongoing activities and planning, can also be identified ahead of time. This paper focuses on the application and implementation of STEMS and also highlights the importance of collaboration for successful implementation.
Groundwater control measures are very important and desirable to implement in urban deep excavati... more Groundwater control measures are very important and desirable to implement in urban deep excavation and tunnelling processes to prevent excessive drawdown and subsequent settlement. They form an integral part of the project to protect the various stakeholders' interests such as deterioration of construction performance and significant impact to existing utility services and building structures. In Singapore's Deep Tunnel Sewerage System Phase 2 (DTSS2) Project, a major used-water infrastructure project, criteria and guidelines for ground water control scheme are outlined in the contract specifications for implementation at all of its deep tunnel shaft excavation sites. In this requirement framework, there is no restriction to the approach, method and procedure used on groundwater control based on prevailing ground condition and construction schedule. Following the guidelines, detail plans and designs for groundwater control scheme such as permeation grouting, pumping test, monitoring & groundwater recharging, are developed for implementation at each tunnel shaft location. However, there are certain sites in the project where implementation of such a pre-groundwater control scheme is subject to own assessment. This paper briefly explains the concept, principle, and procedure implemented, and also reviews the effectiveness and the benefits of groundwater control in construction risk mitigation.
In Singapore, surface rock outcrops and exposures are rare due to thick residual soil cover and i... more In Singapore, surface rock outcrops and exposures are rare due to thick residual soil cover and intensive urbanization. This makes geological and geotechnical studies difficult and inevitably depends largely on deep drilling and geophysical methods. Therefore, deep excavations for underground infrastructure constructions in Singapore carry scientific value as they provide large scale fresh rock exposures for geological observation. Under the Deep Tunnel Sewerage System Phase 2 (DTSS2) Project, deep shaft excavations are carried out at numerous locations in the south and south-western part of Singapore. Depth of excavations range from 30 to 80m, depending on location and topography. Open face mined tunnelling methods are also used in the DTSS2 Project to construct connection adits and Tunnel Boring Machine (TBM) launch chambers. Geologically, DTSS2 Project area is covered by various rock units of Jurong Formation, which was recently refined into Group with different stratotypes and new formations by the Building and Construction Authority (BCA), in accordance with the standards of International Commission on Stratigraphy (ICS). Since the rock type, geological structure, hydrogeological and engineering geological features are properly mapped and documented during the DTSS2 excavation works, it may be of interest to relate and interpret within the BCA’s new stratigraphic framework. This paper intends to share some detailed accounts of geological observations from DTSS2 excavation works for references in future planning and geological investigation works.
Prevailing geological condition as always governs from planning through design and construction o... more Prevailing geological condition as always governs from planning through design and construction of underground infrastructures especially in urban soft ground environment is stressed, as is the significance of vast uncertainty and risk that exists. Comprehensive geological and geotechnical investigation basically helps identifying inherent geological uncertainties and preparing specific project risk-register. Having sub-surface geological longitudinal profile along entire tunnel alignment enables configuring final vertical alignment matching with underground stations. Following routine and detail geological investigation practices, geotechnical insitu (field) and laboratory test results are carefully evaluated as input parameters are used to select of appropriate tunnelling method, tunnel lining design, procurement of Tunnel Boring Machine (TBM), station excavation design; both temporary and permanent structures in design stages. Additionally, the inputs are used to estimate potential ground deformation, and enables setting three threshold levels of geotechnical instrumentation and monitoring; warning, alarm and action level in order to protect the surrounding buildings, roadway structures and underground utilities. If encountering different site condition from the designed geological condition, it is going to be significantly impacted value engineering in term of overall construction cost estimation and scheduling. Therefore, project owner and developer are solely responsible to provide representative geological condition consequently demands pre-excavation ground treatment. When the project is ready to bid, the performance specification and project risk register can be tying into the bidding stage as being contractual obligation for a successful design-builder. In construction stage, construction dewatering impacts the existing groundwater regime and consequently experiencing surface settlements for overlying structures during tunnelling and station construction. Excavation stability plays well under direct geological influence; both urban soft ground shield tunnelling and open-cut station excavation under the Earth Retaining or Stabilising Structures (ERSS). Citing Singapore urban metro-rail projects, the authors suggestively prepared this presentation aiming to propose 8.7 km long proposed metro-rail tunnel section of 28 km long Yangon Mass Rapid Transit Line-1 (YMRT-1), which is currently planning.
Bengal-Arakan Neogene basin is one of the representative clastic basins formed in the frontal par... more Bengal-Arakan Neogene basin is one of the representative clastic basins formed in the frontal part of the Himalayan orogenic belt since late Cenozoic (Kyi Khin et al., 2014, 2017). The basin occupies the eastern part of Paleo-Bengal basin, the biggest basin of the world in Cenozoic. It is located at the unique tectonic setting; a juncture of the collision zone between the Indian and Asian continents to the north and the subduction zone between the Indian Plate and Myanmar Plate to the east. The purpose of the study is to shed some light on the sedimentation in the distal foreland basin of the Himalaya-Bengal System, related with control on timing and distribution of erosional fluxes derived from the uplifted Himalayas since Early Miocene. Chemical weathering strongly affects the major-element geochemistry and mineralogy of siliciclastic sediments. The predicted weathering trend line intersects the feldspar join at the point that shows the proportion of plagioclase and K-feldspar of the fresh rock between granodiorite and granite composition. Moreover, lower Middle Miocene (MM1) samples fall at the lower end of the line (near CN apex), and show a lower Chemical Index of Alteration (CIA) than the other units. This evidence shows the lower intensity of chemical weathering in the lower Middle Miocene than in the Lower Miocene samples. The A-CN-K triangle plots and CIA values suggest granitic and granodioritic composition in most sandstones and shales. Minor enrichment of CN in the middle Miocene sandstones may indicate a relationship of marine transgression that deposited thick gray shale on the Lower Miocene (Laung Formation) as subsequent burial. The presentation will focus on the results of an integrated study of sequence stratigraphy of the Miocene sediments and provenance studies based on the petrography and chemical composition of sandstones and shales, in order to interpret the weathering episode and relationship between tectonic denudation of Himalaya orogenic belts and reciprocal sedimentation related with foreland thrusting of Himalaya-Bengal system. References Kyi Khin, Sakai, T., and Khin Zaw 2014. Neogene syn-tectonic sedimentation in the eastern margin of Arakan-Bengal basins, and its implications for the Indian ering episode and relationship betw Gondwana Research, 26, 89a Res Kyi Khin, Sakai, T., and Khin Zaw 2017. Chapter 5. Arakan Coastal Ranges in western Myanmar, geology and provenance of Neogene siliciclastic sequences: implications for the tectonic evolution of the Himalayath foreland thrusting of Himalaya-Khin Zaw & Crow, M.J. (eds.) Myanmar: Geology, Resources and Tectonics. Geological Society, London, Memoirs, 48, 81mar: Geology, Resources and Tectoni
Tin Tin Naing et al. (2023) recently proposed the Age, Depositional History, and Tectonics of the... more Tin Tin Naing et al. (2023) recently proposed the Age, Depositional History, and Tectonics of the Indo-Myanmar Ranges (IMR) in Myanmar. Although the topic appears intriguing, their interpretation seems inconsistent with several fundamental geological concepts, structural phenomena, and the established geological framework of the Myanmar region. We have several points of discussion to present:
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Papers by Kyi KHIN (DSc, C Geol FGS)
double-wedge system, in which retro-wedge and east-dipping Kabaw Fault are interrelated to form Nappe of Triassic unit (Thanbaya Formation) with double plunging synclines of Chindwin and Minbu-Salin sub-basins. The
Jurassic unit (Kyauksitchaung Formation) is newly found along the eastern base of the IMR as a lithostratigraphic unit and a window structure under the Nappe of the Triassic unit. The alignment of the Kaladan Fault is
newly proposed as a suture zone revealed by the window structures of the Oligocene flysch unit under the Nappe of Neogene units on the onshore area, and localities of the mud volcanoes and structural trend of small islands at the offshore area. The formation of circular structures on the Ramree Archipelago is explained by superimposed folding with heterogenous simple shear deformation of the dome and basin structures due to the NW movement of the Broken-Block of IMR colliding with foreland basins including Chittagong-Tripura Fold Belt (CTFB) and
Baronga (Boronga) Islands.
double-wedge system, in which retro-wedge and east-dipping Kabaw Fault are interrelated to form Nappe of Triassic unit (Thanbaya Formation) with double plunging synclines of Chindwin and Minbu-Salin sub-basins. The
Jurassic unit (Kyauksitchaung Formation) is newly found along the eastern base of the IMR as a lithostratigraphic unit and a window structure under the Nappe of the Triassic unit. The alignment of the Kaladan Fault is
newly proposed as a suture zone revealed by the window structures of the Oligocene flysch unit under the Nappe of Neogene units on the onshore area, and localities of the mud volcanoes and structural trend of small islands at the offshore area. The formation of circular structures on the Ramree Archipelago is explained by superimposed folding with heterogenous simple shear deformation of the dome and basin structures due to the NW movement of the Broken-Block of IMR colliding with foreland basins including Chittagong-Tripura Fold Belt (CTFB) and
Baronga (Boronga) Islands.
Phase 2 (DTSS2) project, 3 of 19 DTSS2’s slurry Tunnel Boring Machines (TBMs) – namely TBM Warwick, TBM Alexandra and TBM Spooner bored through these volcanoclastic rocks in the Alexandra and Kent ridge areas for the construction of a section of South Tunnel and Southern Region Link Sewer Tunnel. The TBM drives took place at a depth of ~35 mBGL under Ayer Rajah Expressway and Alexandra Road where volcanoclastic rocks were encountered in full-face rock condition. In this paper, the performance of slurry TBM drives in the volcanoclastic rocks are summarised and reported with some key tunnelling parameters for appropriate planning of resources and equipment in future tunnelling projects in similar ground condition.
• Site investigation and Monitoring
• Mitigation and regular inspection
Distribution of various types of Volcanogenic Rocks in Jurong Group which recently refined into different stratotypes by the Building and Construction Authority (BCA)
Geological structure, hydrogeological and engineering geological features are properly mapped and documented it may be of interest to relate and interpret within the new Bed Rock Geological Map (BCA, 2018)
nature of hard and soft alternation in sedimentary sequences, weathering depth is highly variable and shows an irregular rockhead profile in most parts of the areas. The relationship between rock mass properties, physio-mechanical properties and the construction challenges were also discussed to provide references for future projects.
References
Kyi Khin, Sakai, T., and Khin Zaw 2014. Neogene syn-tectonic sedimentation in the eastern margin of Arakan-Bengal basins, and its implications for the Indian ering episode and relationship betw Gondwana Research, 26, 89a Res
Kyi Khin, Sakai, T., and Khin Zaw 2017. Chapter 5. Arakan Coastal Ranges in western Myanmar, geology and provenance of Neogene siliciclastic sequences: implications for the tectonic evolution of the Himalayath foreland thrusting of Himalaya-Khin Zaw & Crow, M.J. (eds.) Myanmar: Geology, Resources and Tectonics. Geological Society, London, Memoirs, 48, 81mar: Geology, Resources and Tectoni