Lars Seidler¹

(1) Institute for Energy Research, University of Wyoming, Laramie, WY

ABSTRACT: New Exploration Model for Synrift Turbidite Plays - Outcrop Analogues from the East Greenland Rift System

Seismic-scale exposures of the Lower Triassic succession in East Greenland provide new data on the linkage between rifting and turbidite system geometries. A new exploration model for synrift turbidite plays provides increased prediction of turbidite sandstones in half-graben basins. Rift episodes are subdivided into early, climax, late and postrift stages based on facies characteristics, turbidite system geometries and observed fault displacements.

The early rift stage is characterised by coarse-grained sandy to conglomeratic turbidites deposited in slope-channels/canyons and on basin-floor fans. The rift-climax stage is associated with extensive shale deposition and subordinate, fine to coarse-grained laterally confined basin-floor fans encased in shales. Late stage rifting is characterised by very sand-prone basin-floor fans many tens of metres thick and up to several kilometres in lateral extend. Basin-floor sheet sands also occur in this rift-stage, and are up to 15 m thick and laterally widespread. The postrift stage is associated with fining-upward turbidite systems, which are generally relatively fine-grained and contain an increasing amount of shale. Laterally continuous, up to few tens of metres thick basin-floor fans and sheet sands are observed in this rift-stage. Play models for the turbidite systems emphasise the structural and stratigraphic characteristics of each rifting stage.

The succession in East Greenland is an excellent field analogue to synrift turbidite reservoirs in f.x. the North Sea. The established linkage between rift-stage and turbidite system geometries provides increased reservoir prediction. The presented models can therefore be used in turbidite system exploration and reservoir characterisation.

AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado