Use of 3D digital analogues as templates in reservoir modelling

Geological analogues may be used to rigorously interpret three-dimensional (3D) subsurface reservoir geometry by combining the capabilities of graphic s workstations with digital outcrop data collection. Digital data from sedi mentary environments and outcropping geological formations are interpreted in a 3D viewing environment to construct 3D templates of analogues for rese rvoir bodies. These 3D geometries and associated scaling parameters are the n available to build 3D digital hypotheses concerning subsurface reservoir geometries. Two examples serve to illustrate this approach. Data from a modern fluvial system in the USA are used to construct digital templates. Interpretation o f this dataset enables the relationship between 3D external geometries of s edimentary units to be rigorously defined and related to internal sedimenta ry structures. The location of gas-filled reservoir compartments in the Car boniferous Bend Conglomerate reservoirs of the Boonsville Field in North Te xas are then interpreted using such analogue-derived digital templates.