Imperial College London
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Emeritus ProfessorLidiaLonergan

Faculty of Engineering, Department of Earth Science & Engineering

Emeritus Reader of Geotectonics
 
 
 
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Contact

 

+44 (0)20 7594 6465l.lonergan Website

 
 
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Location

 

3.48Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Mitchell:2021:10.1016/j.marpetgeo.2021.105040,
author = {Mitchell, WH and Whittaker, AC and Mayall, M and Lonergan, L},
doi = {10.1016/j.marpetgeo.2021.105040},
journal = {Marine and Petroleum Geology},
pages = {1--22},
title = {New models for submarine channel deposits on structurally complex slopes: Examples from the Niger delta system},
url = {http://dx.doi.org/10.1016/j.marpetgeo.2021.105040},
volume = {129},
year = {2021}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Submarine channel complexes are often described as having a two-phase stratigraphic evolution where an initial phase of migration is followed by aggradation, generating a ‘hockey-stick shaped’ channel trajectory. However, the role of tectonic forcing in modifying time-integrated sedimentary architectures remains poorly understood. Here, we evaluate how tectonically driven changes in slope modify the evolution—both in terms of morphology and stratigraphic architecture—of submarine channels across a range of spatial scales from the fundamental architectural unit, a channel element, to the scale of a channel complex set, using examples from the Niger Delta system. From a 3D, time-migrated seismic reflection volume, we use amplitude extractions, frequency decomposition and RGB blending to determine channel stratigraphic architectures. These observations are used systematically to evaluate the development of cross-sectional and planform architectures as the channel systems interact with a range of active and pre-existing structural bathymetry. Our results indicate that while a channel complex's stratigraphic architecture may be captured by a two-phase evolution on unstructured slopes, this model fails on structurally complex slopes. Unstructured slope channel complexes display a repeated arrangement of migration dominating the early stratigraphic record and subsequent aggradation. The late aggradational phase signals a decrease in the rate of growth in channel complex width and the rate of change in sinuosity relative to aggradation throughout the complex's development. However, tectonically driven changes in sinuosity and the relative rates of channel migration and aggradation modify complex development significantly. We identify three end-member styles of channel-structure interaction, determined by the timing of bathymetry development and its associated style: (1) pre-channel structural bathymetry; (2) coeval positive relief, and (3) coeval neg
AU  - Mitchell,WH
AU  - Whittaker,AC
AU  - Mayall,M
AU  - Lonergan,L
DO  - 10.1016/j.marpetgeo.2021.105040
EP  - 22
PY  - 2021///
SN  - 0264-8172
SP  - 1
TI  - New models for submarine channel deposits on structurally complex slopes: Examples from the Niger delta system
T2  - Marine and Petroleum Geology
UR  - http://dx.doi.org/10.1016/j.marpetgeo.2021.105040
UR  - https://www.sciencedirect.com/science/article/pii/S0264817221001434?via%3Dihub
UR  - http://hdl.handle.net/10044/1/88302
VL  - 129
ER  -
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