The origin of salt-encased sediment packages: Observations from the SE Precaspian Basin (Kazakhstan)
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Intrasalt sediment packages containing siliciclastic sediments, carbonate sediments, or non-halite evaporites such as gypsum or anhydrite are common within most salt sequences. Intrasalt sediment packages may have been deposited before, during, or after salt deposition and be incorporated into the salt by various processes. Understanding the origin and evolution of intrasalt sediment packages may yield important insights into the tectonic and geodynamic history of the basin, and also into the understanding of salt tectonics. Despite the importance of intrasalt sediment packages, currently there is no systematic description of their possible origins and their distinguishing criteria. This work is divided into three parts. The first part outlines the possible origins of intrasalt sediment packages, as well as criteria to determine if they originated as subsalt, suprasalt or intrasalt sequences. The second part examines how sediment packages that originated on top of salt, such as minibasins, can be encased within salt. Four key encasement processes are proposed: a) salt expulsion from beneath a minibasin experiencing density-driven subsidence; b) salt expulsion from beneath adjacent subsiding minibasins; c) salt expulsion associated with lateral shortening; d) override of minibasins by a salt sheet sourced from elsewhere. The third part of the paper presents a case study from the SE Precaspian Basin, Kazakhstan, where, using a borehole-constrained 3D seismic reflection dataset, the proposed criteria are applied to an area with abundant, newly discovered sediment packages within salt.
Date Issued
2017-01-28
Date Acceptance
2017-01-25
Citation
Journal of Structural Geology, 2017, 97 (April 2017), pp.237-256
ISSN
0191-8141
Publisher
Elsevier
Start Page
237
End Page
256
Journal / Book Title
Journal of Structural Geology
Volume
97
Issue
April 2017
Copyright Statement
© 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND
license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Identifier
http://www.sciencedirect.com/science/article/pii/S0191814117300172?dgcid=raven_sd_via_email
Subjects
Science & Technology
Physical Sciences
Geosciences, Multidisciplinary
Geology
Salt tectonics
Intrasalt
Minibasins
Encased minibasins
Precaspian Basin
GULF-OF-MEXICO
ALLOCHTHONOUS SALT
PRICASPIAN BASIN
SANTOS BASIN
SEISMIC DATA
EVOLUTION
DEFORMATION
SUBSIDENCE
LOUISIANA
ZECHSTEIN
Geochemistry & Geophysics
0403 Geology
Publication Status
Published