Rock matrix and fracture analysis of flow in western tight gas sands. Annual report, 1985

Technical Report · Sat Mar 01 04:00:00 EST 1986

OSTI ID:6130735

Morrow, N R; Ward, J S; Brower, K R

This report presents results of a joint project with the US Department of Energy on low permeability gas sands. Core material has been obtained through the Multi-Well project. Thirty-one matrix (non-fractured) cores have been tested for the effects of formation net overburden pressure, on gas flow. The cores are highly sensitive to confining pressure, and it is essential that they be tested at formation conditions. Three basic features of the pore structure of low permeability gas sands have been identified. These are sheet pores at grain boundaries, solution pores formed from unstable rock grains and cements, and microporosity which can arise from a variety of materials such as clays and chert. Flow measurements, surface area determinations, adsorption isotherms and other techniques have been used to investigate the structural features of tight sands. Economic production of low permeability gas sands depends on the presence of fractures. Experiments with cores containing calcite-filled fractures show that the fractures often have about the same permeability as the surrounding matrix, but can sometimes provide relatively conductive pathways for gas flow. Ancient open (not cement-filled) fractures which will be very important to gas production from tight sands have also been identified. 40 refs., 34 figs., 8 tabs.

• Research Organization: New Mexico Inst. of Mining and Technology, Socorro (USA). New Mexico Petroleum Recovery Research Center
• OSTI ID: 6130735
• Report Number(s): NMERDI-2-73-4313; ON: DE86008257
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
030200* -- Natural Gas-- Reserves
Geology
& Exploration
ADSORPTION
ADSORPTION ISOTHERMS
COMMINUTION
CRUSHING
DATA
DESORPTION
DRILL CORES
ELEMENTS
EXPERIMENTAL DATA
FAILURES
FLUID FLOW
FRACTURED RESERVOIRS
FRACTURES
GAS FLOW
HYDROGEN COMPOUNDS
INFORMATION
ISOTHERMS
MINERALOGY
NITROGEN
NONMETALS
NUMERICAL DATA
OXYGEN COMPOUNDS
PERMEABILITY
POROSITY
ROCKS
SANDSTONES
SATURATION
SEDIMENTARY ROCKS
SORPTION
SURFACE AREA
SURFACE PROPERTIES
WATER
WATER SATURATION
WELL SPACING