Relationship of the H_2 gas anomaly with earthquakes in L intong observatory;

Analyzing the principle and theoretical basis of radon survey and relations between radon anomalies and different geologic phenomena,this paper proposes criteria for determining radon anomaly and features of radon emanation anomaly.

The distribution of radon anomaly coincides with the anomaly model established by the authors.

n order to produce a reliable survey method for the study prediction as well as prevention and control of ground fissure, the possibility of radon anomaly is, firstly, analyzed in ground fissure started with the basic principle of surveying radon and the genetic mechanism of ground fissure.

Re-delimitation of gas logging abnormal criteri a for low pressure & low permeability gas zones in the Northern Erdos.;

The geogas prospecting has thus revealed the ring fracture structure 4?000?m deep and the location of the geogas anomaly above the ring fracture structure perpendicular to each other.

The shape of geogas anomaly has something to do with the extension of concealed fault.