Mass Transport Deposits: Combined Outcrop Studies, 3-D Seismic Interpretation and Forward Modeling

Benjamin Kneller¹, Mason Dykstra², Philip Thompson¹, Vanessa Ketznus¹, Magdalena Szuman¹, Katerina Garyfalou¹, Matteo Molinaro¹, Mads Huuse¹, Peter Butterworth³, David Macdonald¹, and Juan Pablo Milana^4
1 University of Aberdeen, Aberdeen, United Kingdom
² University of California, Santa Barbara, CA
³ BP Egypt, Cairo, Egypt
⁴ Universidad de La Serena, La Serena, Chile

The shallow parts of 3D seismic surveys offer outstanding views of the three-dimensional structure of mass transport deposits, but with little or no well calibration to establish lithology or core/outcrop scale structure – both of which are essential to an understanding of the properties and origin of the deposit. Truly seismic-scale outcrops of mass transport deposits are rather rare, but study of the rock record is vital to the acquisition of an understanding of their structural evolution, lithofacies distribution and reservoir or barrier potential. We present some models of architecture and lithologic distribution based on a combination of very large scale outcrops and 3D seismic, which we have used to generate seismic forward models. These are based on two end-member types of deposit; a Mesozoic slide complex in Antarctica (MacDonald et al., 1993), and a chaotic debris flow of Carboniferous age in NW Argentina, the latter mapped in detail in 3D using laser-based digital mapping techniques. We discuss the relations between the macro- (seismic) and meso- (outcrop/core) scales of observation of structure and lithofacies distribution, and suggest some preliminary approaches to subsurface prediction.

Macdonald, D.I.M, Moncrieff, A.C.M. and Butterworth, P.J., 1993. Giant slide deposits from a Mesozoic fore-arc basin, Alexander Island, Antarctica. Geology; November 1993; v. 21; no. 11; p. 1047-1050.