【摘要】 天津地区的地质构造条件复杂,其中大部分地区被新生代沉积物深度覆盖,地势以平原和洼地为主,北部有少量低山丘陵,平原约占93%。因此,天津市测震台网地震观测台站除蓟县台有基岩出露台外,其余台站均为井下地震观测。而井下地震计维修价格昂贵且不易维修,同时还面临着由于井下电缆损毁,地震计无法回收等问题。为此,天津市测震台网一直在寻找一种可替代现有井下观测的新方式,以应对深覆盖层地震观测存在的问题。本文通过地震观测,完成了一地多台基情况下台基噪声的对比试验,得到了很好的对比结果。该方法适合在其它类似天津这样沉积层较厚的地区推广使用,可达到简化地震计安装、降低设备维护成本和方便维护的目的。更多还原

【Abstract】 Tianjin area is covered by the thick Cenozoic sediments, with complicated geological structure, and plain and depression in topography.The plain occupies about ninety-three percent of the total area.As the results,all stations in Tianjin seismic network are underground observation except Jixian station. Since The borehole seismometer is expensive and difficult to maintain, We search the new way which may replace the underground observation.Some preliminary results in the testing system of ambient seismic noise contrast test are reported in this paper.更多还原