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Characteristics of a sandy depositional lobe on the outer Mississippi fan from SeaMARC IA sidescan sonar images

David C. Twichell·William C. Schwab·C. Hans Nelson·Neil H. Kenyon·Homa J. Lee
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Abstract

SeaMARC IA sidescan sonar images of the distal reaches of a depositional lobe on the Mississippi Fan show that channelized rather than unconfined transport was the dominant transport mechanism for coarse-grained sediment during the formation of this part of the deep-sea fan. Overbank sheet flow of sands was not an important process in the transport and deposition of the sandy and silty sediment found on this fan. The dendritic distributary pattern and the high order of splaying of the channels, only one of which appears to have been active at a time, suggest that coarse-grained deposits on this fan are laterally discontinuous.

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GeologyArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 23.926013033021192° to 28.806173508854776° latitude; -93.69140625° to -84.5947265625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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David C. Twichell, William C. Schwab, C. Hans Nelson, Neil H. Kenyon, Homa J. Lee. 1992. Characteristics of a sandy depositional lobe on the outer Mississippi fan from SeaMARC IA sidescan sonar images. https://doi.org/10.1130/0091-7613(1992)020%3C0689%3Acoasdl%3E2.3.co%3B2

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