(Geo-Engineering Modeling through INternet Informatics)

Kansas Geological Survey
Open-file Report 2002-10

Rock Catalog

A fundamental goal of reservoir characterization is to quantitatively define the distribution of reservoir properties including porosity, permeability, fluid saturations, capillary pressure, relative permeability, electrical properties and compressibility. Other GEMINI modules call and summarize available data for a given location. For locations where little or no data are available it is necessary to compile analog data or utilize “type” petrophysical data that is no longer location-specific but is rock-specific.

Different lithologic facies generally exhibit unique storage and flow characteristics due to unique pore architectures resulting from lithologic controls. While the horizontal and vertical distribution of lithofacies can vary widely within and between reservoirs, the petrophysical properties of specific lithofacies are often consistent over large regions and even globally. It is thus possible to apply lithofacies-specific petrophysical properties measured on cores from a limited number of reservoirs to intervals in many other reservoirs exhibiting that same lithofacies. Just as there are "type" sections and "type" logs, there are "type" petrophysical samples. The development of accurate lithofacies-petrophysical equations requires that each lithofacies be sampled adequately over the range of lithologic and petrophysical properties that it exhibits.

An efficient and useful format for the database of lithologic and petrophysical properties is a rock catalog. A “page” of the catalog represents a specific lithofacies sample with specific petrophysical properties shown against a user-selected backdrop of other samples of similar lithologic, petrophysical, formational, or other characteristics. A catalog “page,” constructed on-demand and based on search critieria that the user specifies to view selected “type” rock information, illustrates the specific sample properties and general lithofacies properties. Much like a bird book, an operator can simply "look up" a lithofacies within a general porosity range to obtain information on a suite of petrophysical properties exhibited by that lithofacies.

top of report

e-mail :
Last updated March 2002