Abstract
The elongate north-south trending Central Myanmar Basin (CMB) is bounded to the west by the Indo Myanmar Ranges (IMR) and to the east by the Sino Myanmar Ranges (SMR). The CMB is further sub-divided into a series of sub-basins, including the centrally-located Salin sub-basin. During the Cenozoic, sedimentation into the Salin sub-basin was continuous and abundant, leading to the accumulation of almost 18 km of deposits. This research focuses on the Oligocene Shwezetaw, Padaung, and Okhmintaung Formations to reconstruct the depositional environment, the sediment routing pathways into the basin, any source switching. This was achieved through a field campaign followed by subsequent sedimentary provenance analysis on light and heavy minerals and U-Pb dating of detrital zircons. This work will incorporate palynology and ichnology to try to better understand the evolution of the basin.
The Salin sub-basin is little studied, especially through field campaigns. This work provides an opportunity to document changes in sediment sources and tectonic changes during the early stages of India-Asia collision and help to constrain the timing of uplift of the IMR and SMR.
The Shwezetaw Formation is interpreted as a southward-flowing fluvial system that grades through a tidally-dominated deltaic environment into shallow marine. A gradual regression through the Rupelian caused a southerly progradation of the delta. The Padaung Formation records a deepening event, with rare fluvial deposits occurring in the north, and abundant deltaic and shallow marine in the south. The Okhmintaung Formation is interpreted as a tidally-influenced deltaic environment, with little temporal variation. Despite no evident switch observed the light minerals and U-Pb zircon ages, the heavy minerals suggest a mixing from material coming from further afield, possibly from the north of the CMB, and locally sourced material from the ophiolites accreted along the Indo Myanmar Ranges.
The Salin sub-basin is little studied, especially through field campaigns. This work provides an opportunity to document changes in sediment sources and tectonic changes during the early stages of India-Asia collision and help to constrain the timing of uplift of the IMR and SMR.
The Shwezetaw Formation is interpreted as a southward-flowing fluvial system that grades through a tidally-dominated deltaic environment into shallow marine. A gradual regression through the Rupelian caused a southerly progradation of the delta. The Padaung Formation records a deepening event, with rare fluvial deposits occurring in the north, and abundant deltaic and shallow marine in the south. The Okhmintaung Formation is interpreted as a tidally-influenced deltaic environment, with little temporal variation. Despite no evident switch observed the light minerals and U-Pb zircon ages, the heavy minerals suggest a mixing from material coming from further afield, possibly from the north of the CMB, and locally sourced material from the ophiolites accreted along the Indo Myanmar Ranges.
| Original language | English |
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| Publication status | Published - 2018 |
| Event | AGU Fall Meeting 2018 - Washington, D. C., United States Duration: 10 Dec 2018 → 14 Dec 2018 |
Conference
| Conference | AGU Fall Meeting 2018 |
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| Country/Territory | United States |
| City | Washington, D. C. |
| Period | 10/12/18 → 14/12/18 |