|
Kansas Geological Survey Open-file Report 2001-38 |
Porosity in L-KC oomoldic limestones ranges from 0-35%. Generally rocks exhibiting porosity below 15% porosity are non-reservoir.
Permeability (0.001-400 md) is principally controlled by:
Porosity
Oomold connectivity
Other variables that exert influence but are colinear with the above variables include:
Oomold diameter
Oomold packing
Matrix properties
Matrix fracturing/crushing
Although permeability is controlled by and correlates with several of these variables (below), multivariate linear regression methods only improve prediction from a factor of 6.9X to 5.4X by inclusion of information concerning connectivity index, as measured on rock pieces.
Basic porosity equation:
log k = 0.112 phi - 2.48 SE = 7X With Connectivity Index: log k = 0.090 phi + 0.47 Connectivity Index - 3.21 SE=5.5X
Individual wells generally exhibit k-phi trends with less variance than the overall trend. Development of models for specific fields, representing unique associations of conditions, allows the most accurate prediction.
e-mail : webadmin@kgs.ku.edu
Last updated December 2001
http://www.kgs.ku.edu/PRS/publication/OFR2001-38/P3-02.html