Tight gas sands are a vast future source of natural gas. These sands are characterizd as having very low porosity and permeability. The main resource development problem is efficiently extracting the gas from the reservoir. Future production depends on a combination of gas price and technological advances. Gas production can be enhanced by fracturing. Studies have shown that many aspects of fracture design and gas production are influenced by properties of the rock matrix. Computer models for stimulation procedures require accurate knowledge of flow properties of both the rock matrix and the fractured regions. In the proposed work, these properties will be measured along with advanced core analysis procedures aimed at understanding the relationship between pore structure and properties. The objective of this project is to develop reliable core analysis techniques for measuring the petrophysical properties of tight gas sands. Recent research has indicated that the flow conditions in the reservoir can be greatly enhanced by the presence of natural fractures, which serve as a transport path for gas from the less permeable matrix. The study is mainly concerned with the dependence of flow in tight gas matrix and haled tectonic fractures on water saturation and confining pressure. This dependencey is to be related to the detailed pore structure of tight sands as typified by cores recovered in the Multi-Well experiment. 22 refs., 34 figs., 9 tabs.