3-D MONARCH Reservoir Modelling as a Development Tool: West Salym Field, Western Siberia, Russia

R. B. Ainsworth, A. van Kuyk, J. van Lieshout, M. Nepveu I. Stulemeijer, J. van der Vorst, and J. A. Spilsbury-Schakel

The Salym fields are located in the central part of the West Siberian basin. The basin developed during the Triassic and contains an almost complete stratigraphic succession from the Jurassic to the Quaternary. The main oil reserves in the Salym fields are located in the Lower Cretaceous prograding deltaic complex.

The principal reservoir section in the West Salym field is interpreted as marginal marine. Shoreface, mouthbar, fluvial channel and crevasse-splay sub-environments are recognised. Due to this range of depositional environments and average (exploration) well spacing of 5 km, 3-D modelling of depostional geometries is essential to determine the reservoir architecture and reservoir property trends prior to full-scale field development.

The Shell proprietary correlation software package GEOLOGIX and 3-D modelling package MONARCH were utilised to enable rapid evaluation of a range of geological and petrophysical scenarios. For example, differing correlation scenarios reflecting geological uncertainties such as reservoir continuity and connectivity can be generated using GEOLOGlX and rapidly screened in MONARCH.

The resulting oil-in-place and recovery efficiency of various development scenarios can then be assessed for each model. For instance, the potential impact of interpreted dipping intra-shoreface shales can be quantified.

AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California