Publication Date:
2022-05-26
Description:
© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Gadol, O., Tibor, G., ten Brink, U., Hall, J. K., Groves-Gidney, G., Bar-Ann, G., Huebscher, C., & Makovsky, Y. Semi-automated bathymetric spectral decomposition delineates the impact of mass wasting on the morphological evolution of the continental slope, offshore Israel. Basin Research, (2019): 1-28, doi: 10.1111/bre.12420.
Description:
Understanding continental‐slope morphological evolution is essential for predicting basin deposition. However, separating the imprints and chronology of different seafloor shaping processes is difficult. This study explores the utility of bathymetric spectral decomposition for separating and characterizing the variety of interleaved seafloor imprints of mass wasting, and clarifying their role in the morphological evolution of the southeastern Mediterranean Sea passive‐margin slope. Bathymetric spectral decomposition, integrated with interpretation of seismic profiles, highlights the long‐term shape of the slope and separates the observed mass transport elements into several genetic groups: (1) a series of ~25 km wide, now‐buried slide scars and lobes; (2) slope‐parallel bathymetric scarps representing shallow faults; (3) slope‐perpendicular, open slope slide scars; (4) bathymetric roughness representing debris lobes; (5) slope‐confined gullies. Our results provide a multi‐scale view of the interplay between sediment transport, mass transport and shallow faulting in the evolution of the slope morphology. The base of the slope and focused disturbances are controlled by ~1 km deep salt retreat, and mimic the Messinian base of slope. The top of the open‐slope is delimited by faults, accommodating internal collapse of the margin. The now‐buried slides were slope‐confined and presumably cohesive, and mostly nucleated along the upper‐slope faults. Sediment accumulations, infilling the now‐buried scars, generated more recent open‐slope slides. These latter slides transported ~10 km3 of sediments, depositing a significant fraction (~3 m in average) of the sediments along the base of the studied slope during the past 〈 50 ka. South to north decrease in the volume of the open‐slope slides highlight their role in counterbalancing the northwards diminishing sediment supply and helping to maintain a long‐term steady‐state bathymetric profile. The latest phase slope‐confined gullies were presumably created by channelling of bottom currents into slide‐scar depressions, possibly establishing incipient canyon headword erosion.
Description:
Funding for this study was provided by the State of Israel Ministry of Science and Technology grant 3–9145. Omri Gadol studies were supported by the State of Israel Ministry of Energy grants program, the Dr. Moses Strauss Department of Marine Geosciences and the Hatter Department of Marine Technologies. We thank the Oil Commissioner Office, State of Israel Ministry of Energy, Delek Drilling, Adira Energy and Modiin Energy for data sharing and permitting; and Emerson‐Paradigm for sponsoring their software. We also thank Alexander Surdyaev, AMEL, for his constant support; and David Mosher, Glen Sherman and Jason Chaytor for their valuable reviews.
Keywords:
landslide volume
;
Levant Basin
;
mass transport complexes
;
morphometric analyses
;
semi‐automated mapping
;
slope confined gullies
;
submarine slide
;
thin skin faulting
Repository Name:
Woods Hole Open Access Server
Type:
Article
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