This paper firstly defined construction contract risk and the foreseeable risk principle on the basis of the risk s meaning.

According to main manifestation of engineering contract risk, risk prevention in contract management and rational order of risk distribution,the author analyzes risk management of engineering contract,and proposes the methods to avoid and distribute risks in concrete project contract management from the angle of applicability,in order to promote well development of construction enterprise.

The main works of contract risk analysis are identification of these risks, effective reduction and avoidance of contract risk by way of effective countermeasures with appraisal of contract on contractor organization.

When the construction contract is prepared, all the issues discussed in this paper should be reasonably considered for the proper definition of the contract risks and lowering the probability of arising disputes because of the defects of the contract.

The explanation focuses on the division of risk types about engineering contract of petroleum construction enterprises, coupled with the precaution measures and countermeasures of contract risks about oil construction installing projects.

A portfolio optimization model for petroleum exploration projects with consideration of geological risk;

In the models of geological risk for the lithological trap,the appraisal parameters are classified into three levels or aspects i.

The basic principle and its relevant mathematics models of geological risk probability method, fuzzy set comprehensive assessment method and minimum economic reserves size are introduced systematically in this .