Отправлено: 02.07.13 06:58. Заголовок: An improved technique for modeling initial reservoir hydrocarbon saturation distributions: applicati

An improved technique for modeling initial reservoir hydrocarbon saturation distributions: applications in Illinois USA Aux Vases  /oil reservoirs
Emmanuel Udegbunam, Jude O. Amaefule

Received 20 August 1996; accepted 26 June 1998

Abstract
An improved technique for modeling the initial reservoir hydrocarbon saturation distributions is presented. In contrast to
the Leverett J-function approach, this methodology hereby termed flow-unit-derived initial oil saturation or FUSOI  .
determines the distributions of the initial oil saturations from a measure of the mean hydraulic radius, referred to as the flow
zone indicator FZI . FZI is derived from porosity and permeability data. In the FUSOI approach, capillary pressure  .
parameters, S , P , and l, derived from the Brooks and Corey 1966 model Brooks, R.H., Corey, A.T., 1966. Hydraulic  . w
wir d
properties of porous media, Hydrology Papers, Colorado State Univ., Ft. Collins, No. 3, March. , are correlated to the FZI. x
Subsequent applications of these parameters then permit the computation of improved hydrocarbon saturations as functions
of FZI and height above the free water level FWL . This technique has been successfully applied in the Mississippian Aux  .
Vases Sandstone reservoirs of the Illinois Basin USA . The Aux Vases Zeigler field Franklin County, IL, USA was .  .
selected for a field-wide validation of this FUSOI approach because of the availability of published studies. With the initial
oil saturations determined on a depth-by-depth basis in cored wells, it was possible to geostatistically determine the
three-dimensional 3-D distributions of initial oil saturations in the Zeigler field. The original oil-in-place OOIP , computed  .  .
from the detailed initialization of the 3-D reservoir simulation model of the Zeigler field, was found to be within 5.6% of the
result from a rigorous material balance method. q1998 Elsevier Science B.V. All rights reserved.

Journal of Petroleum Science and Engineering 21 1998 143–152