It was considered that oil-gas in free phase was sealed by the replacement pressure of lower tight layer,overpressure cannot seal oil-gas in free phase directly,but overpressure can reflect the minimum value of seal ability of over-pressured mudstone caprock for oil-gas in free phase.

Gas in water-dissolving phase was considered to be sealed by adsorptive force of lower tight layer.

A new method to study stress sensitivity analysis of tight reservoir and its influence on oilfield development;

Stress sensitivity of tight reservoir and its influence on oilfield development;

Single factor diagenetic facies analysis of tight reservoir in western Sichuan foreland basin;

The authors think that the compact reservoir fracture in T3-J Formation in the north of the Chuxiong basin are mainly the tectonic fractures controlled by local structures based on the results of field fracture survey, description of bore core and identification of well logging.

This paper analyzes log responses of tight formations and tight gas reservoirs, correlates vertical formations in a same well and lateral formations in different wells and intra-formational response as well, uses graphic calibration method, analyzes the characteristics of logging curves of tight formations from different perspectives, and thus determines gas potential of tight formation.

A compact layer on the surface, which is an anti-oxidation and anti-corrosion layer, formed spontaneously in MgO/ Si3N4 composite in the process of oxidation, and the thickness and density of the compact layer increased by adding Si or Al into the composite.