AAPG Bulletin, V. 83 (1999), No. 1 (January 1999), P. 43-61.

A Conceptual Tectonostratigraphic Model for Seismic Facies Migrations in a Fluvio-Lacustrine Extensional Basin¹

Uwe Strecker,² J. R. Steidtmann,³ and S. B. Smithson³
 

©Copyright 1999.  The American Association of Petroleum Geologists.  All Rights Reserved

¹Manuscript received April 29, 1996; revised manuscript received March 13, 1998; final acceptance April 13, 1998.
²Sebastian-Kneipp-Str. 32, 37217 Witzenhausen, Germany.
³Department of Geology & Geophysics, University of Wyoming, Laramie, Wyoming 82071.

We thank Shell Western Exploration and Production Incorporated (SWEPI) for permission to publish the seismic data. Strecker thanks Ron Steel for discussion and improvements on an earlier version of this manuscript. Reviews by R. M. Mitchum, J. J. Lambiase and former AAPG Bulletin editor K. T. Biddle contributed to the final manuscript. 

ABSTRACT

One of the most fundamental differences between lacustrine basins and many marine basins is the stratigraphic response to differential tectonic subsidence. Because the water volume of a lake is finite, tilting of the valley floor redistributes the lake water. If the lake water level is below a hinge point (fulcrum) that experiences no net subsidence, the lake shoreline is translated toward the site of subsidence, and a deeper lake forms. This tectonostratigraphic model for rift-lake sedimentation is tested in a seismic and sequence stratigraphic study of deltaic and lacustrine deposits that accumulated in a Cenozoic extensional basin beneath Goshute Valley, Nevada. Seismic sequences exhibit an internal, cyclic stacking hierarchy of seismic reflections interpreted as the stratigraphic response of a lowstand paleolake to tectonism (forced regression) and subsequent lake level restoration (transgressive and highstand systems tracts).