| 초록 |
The hydrogen and oxygen stable isotopic composition and the helium isotopic composition of the hot spring water in the Northern Margin Fault Zone of Qinling are studied. Making use of heat reservoir temperature, and in connection with the local geothermal gradients, circulation depth of the hot spring waters is calculated. Meanwhile frequency of earthquakes occurring from 1900 to 1997 is counted up and analyzed. Form the point of view of weakening effect of water on fault and its wall rocks, the effect of deep circulation of the hot spring water on seismic activity is discussed. The result indicates that difference of seismic activity among each segment is related to difference of the circulation depth of hot spring water in each segment. It is suggested that a risk of strong earthquake is less possible on the Shanxi segment in which the depth is greater, but are more possible on the Gansu segment and the Qinghai segment in which the depth is smaller, and it is most possible on the Gansu segment. |
