AAPG ANNUAL CONFERENCE AND EXHIBITION
Making the Next Giant Leap in Geosciences
April 10-13, 2011, Houston, Texas, USA
Integrated Sand Source Directions, Provenance and Stratigraphy in the Møre and Vøring Basins
(1) Fugro Robertson Ltd., Llandudno, United Kingdom.
The deepwater areas of the Norwegian Sea represent a key area for exploration and exploitation. The first deepwater blocks were awarded in 1996 (including the Ormen Lange discovery). Interest has been maintained with recent gas discoveries in Upper Cretaceous sands in the Asterix and Gro wells. Understanding the provenance and emplacement direction of these reservoir sand bodies, and its influence on reservoir quality is a key challenge to exploiting these resources.
An integrated study of sediment source areas, transport directions, stratigraphy and depositional environment has been carried out using a range of complementary techniques to enhance our understanding of Cretaceous and Paleocene reservoir sand distribution in the Møre and Vøring Basins.
QEMSCAN® analysis has been used to fully characterise mineralogy, including broad-scale sand provenance directions determined from heavy minerals to discriminate sand source lithologies within the wells studied. Source directions of specific sand units have been determined from anisotropy of magnetic susceptibility measurements on core samples, re-oriented to palaeogeographic North using the palaeomagnetic method. These data are further supported by inorganic geochemical data from XRF analyses, resulting in an integrated picture of sand sources, sediment input points and sand transport directions within the Cretaceous of the Møre and Vøring Basins.
The inorganic geochemical and mineralogical data have been used also, in conjunction with traditional micropalaeontological and palynological data, to refine sequence stratigraphic models through generation of an integrated correlation and zonation scheme. These data have resulted in an increased confidence in the correlation of sands, especially where biostratigraphic resolution is more limited.
QEMSCAN® data have also been used to provide detailed assessment of pore size and orientation within reservoir sand units. In conjunction with permeability anisotropy determinations on specific sand units derived using the Magpore pore fabric method this has elucidated reservoir fluid-flow properties and will contribute to the development of refined reservoir models.