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Title: Crustal structure and sedimentation history over the Alleppey platform, southwest continental margin of India: Constraints from multichannel seismic and gravity data

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Publication Date:
Sponsoring Org.:
USDOE Office of Fossil Energy (FE), Oil and Natural Gas (FE-30)
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Resource Type:
Journal Article: Published Article
Journal Name:
Geoscience Frontiers
Additional Journal Information:
Journal Volume: 9; Journal Issue: 2; Related Information: CHORUS Timestamp: 2018-02-15 02:11:30; Journal ID: ISSN 1674-9871
Country of Publication:
Country unknown/Code not available

Citation Formats

Unnikrishnan, P., Radhakrishna, M., and Prasad, G. K. Crustal structure and sedimentation history over the Alleppey platform, southwest continental margin of India: Constraints from multichannel seismic and gravity data. Country unknown/Code not available: N. p., 2018. Web. doi:10.1016/j.gsf.2017.06.002.
Unnikrishnan, P., Radhakrishna, M., & Prasad, G. K. Crustal structure and sedimentation history over the Alleppey platform, southwest continental margin of India: Constraints from multichannel seismic and gravity data. Country unknown/Code not available. doi:10.1016/j.gsf.2017.06.002.
Unnikrishnan, P., Radhakrishna, M., and Prasad, G. K. 2018. "Crustal structure and sedimentation history over the Alleppey platform, southwest continental margin of India: Constraints from multichannel seismic and gravity data". Country unknown/Code not available. doi:10.1016/j.gsf.2017.06.002.
title = {Crustal structure and sedimentation history over the Alleppey platform, southwest continental margin of India: Constraints from multichannel seismic and gravity data},
author = {Unnikrishnan, P. and Radhakrishna, M. and Prasad, G. K.},
abstractNote = {},
doi = {10.1016/j.gsf.2017.06.002},
journal = {Geoscience Frontiers},
number = 2,
volume = 9,
place = {Country unknown/Code not available},
year = 2018,
month = 3

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.gsf.2017.06.002

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  • As eustasy, subsidence, and sediment accumulation vary, a 2D computer-based graphical simulation generates on-lapping and off-lapping geometries of both marine and near coastal alluvial deposits, reproducing timelines within sediment-bodies at basin margins. In the simulation, deposition is expressed by creation of new surfaces above previous ones. Thicknesses of layers are reduced by both erosion and compaction while their surfaces move vertically in response to tectonic change and loading. Simulation is divided into a series of equal time steps in which sediment is deposited as an array of en-echelon columns that mark the top of the previous depositional surface. The volumemore » of sediment deposited in each time step is expressed as a 2D cross section and is derived from two right-angle triangles (sand and shale), whose areas are a 2D expression of the quantity of sediment deposited at that time step and whose length matches the width of the offshore sediment wedge seaward of the shoreline. Each column in the array is filled by both marine sediments up to sea level, and alluvial sediments to a surface determined by an alluvial angle that is projected landward from the shore to its intersection with the previous surface. Each time the area representing the sediment column is subtracted from the triangles, the triangle heights are reduced correspondingly. This process is repeated until the triangle heights match the position of sea level above the sediment surface, at which time the remaining area of the sediment triangle is deposited seaward as a single wedge of offshore sediments. This simulation is designed to aid interpretation of stratigraphic sequences. It can be used as a complement to seismic stratigraphy or can be used alone as an inexpensive test of stratigraphic models.« less
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