112 short-period seismographs were set up in the 400 km^2 area of Pingtan Island and its surrounding areas in Fujian.The combined observations of the airgun source and ambient noise source were carried out using a den...112 short-period seismographs were set up in the 400 km^2 area of Pingtan Island and its surrounding areas in Fujian.The combined observations of the airgun source and ambient noise source were carried out using a dense array to receive the 387 airgun signals excited around the island and one month of continuous ambient noise recording.The 1-D P-wave and S-wave shallow velocity model of Pingtan Island is obtained by the inversion of the airgun body wave’s first arrival time data,and the reliability of the velocity model is verified by using the surface wave phase velocity dispersion curve,which can provide initial model for subsequent 3-D imaging.The experimental results show that this experiment is a successful demonstration of local scale green non-destructive detection,which can provide basic data for shallow surface structure research and strong vibration simulation of the Pingtan Island.展开更多
基金sponsored by the Key Technologies R&D Program of Fujian Earthquake Agency(G201703)the Seismic Science and Technology Spark Program,CEA(XH19023Y)
文摘112 short-period seismographs were set up in the 400 km^2 area of Pingtan Island and its surrounding areas in Fujian.The combined observations of the airgun source and ambient noise source were carried out using a dense array to receive the 387 airgun signals excited around the island and one month of continuous ambient noise recording.The 1-D P-wave and S-wave shallow velocity model of Pingtan Island is obtained by the inversion of the airgun body wave’s first arrival time data,and the reliability of the velocity model is verified by using the surface wave phase velocity dispersion curve,which can provide initial model for subsequent 3-D imaging.The experimental results show that this experiment is a successful demonstration of local scale green non-destructive detection,which can provide basic data for shallow surface structure research and strong vibration simulation of the Pingtan Island.
文摘对闽南沿海兄弟屿西南部的侵入岩开展了LA-ICP-MS锆石U-Pb年代学及全岩地球化学研究,获得2组锆石^(206)Pb/^(238)U加权平均年龄,其中(241±3.6) Ma为岩体侵入年龄(印支期),(141±5.1) Ma可能为后期热液事件年龄(燕山期)。岩石属高钾钙碱性弱过铝质花岗岩,轻、重稀土分馏程度强烈,具有中强的Eu负异常(δ Eu 0.39~0.45)和富集大离子亲石元素特征,显示S型花岗岩。其构造背景可能与古太平洋板块及滨海断裂带等活动有关,兄弟屿的侵入岩体发现为该地区构造-岩浆演化提供新的时空约束信息。
