DYNAMIC STRATIGRAPHY WORKGROUP

Autostratigraphy. Geometrical and experimental model of foreland basins

 

People:

Julio Leva López, Wonsuck Kim, Ronald J. Steel

 

Research question(s):

What is the “default” evolution (autostratigraphy) of deltas and shelf margins in foreland basins?

 

Summary of work:

Autostratigraphy is the study of the intrinsic or “default” evolution of sedimentary systems, when the external forcing is present but unchanging (steady). Until now it has been studied only in cases of homogenous subsidence.

We are creating a numerical model where, in constrast to previous studies, the deltaic and shelf clinoforms develop under back-tilting differential subsidence. Preliminary results indicate that these clinoforms will exhibit two distinct behaviors depending on the imposed rate of back-tilting subsidence; one showing the classic autoretreat signal and another showing an accelerated regression (henceforth “autoaccelerated regression” to follow the autostratigraphic nomenclature).

These numerical results have been tested in the brand new “UT Experimental Delta Basin” flume tank. All the boundary conditions (i.e. sediment supply, subsidence, water level and water discharge) in the UTEDBasin are very precisely controlled, which allowed to perform a series of experiments that confirmed the results of the numerical model.

 

Publications and presentations:

 

Conference/meeting presentations:

Leva López, J., Kim, W. and Steel, R.J., 2011, Clastic Wedge Autogenic Behavior in Foreland Basins: Numerical and Experimental Model. 28th IAS Meeting of Sedimentology. Zaragoza, Spain.

 

Leva López, J., Kim, W. and Steel, R.J., 2010, Autostratigraphic response of clinoform evolution to back-tilting subsidence – A Numerical Model. 18th International Sedimentological Congress, Mendoza, Argentina.