VOLCANIC RIFTED MARGINS，MARINE GAS HYDRATES AND SE...
Song Haibin1，2 Fang Yinxia2 Zhang Wensheng3
（1.Institute of Geology and Geophysics，Chinese Academy of Sciences，Beijing 100029，China；2.Key Lab of Submarine Geosciences of State Oceanic Administration，Hangzhou 310012，China；3.Institute of Computational Mathematics and Scientific/Engineering Computing，Chinese Academy of Sciences，Beijing 100080，China）
Abstract：Since the theory of plate tectonics was proposed in the 1960s，marine gas hydrates and volcanic rifted margins have attracted lots of marine geophysicists and geologists and become main objectives of DSDP and ODP.Seismic methods played important roles in their discoveries known as BSR（Bottom simulating reflectors）in 1970 and SDR（seaward dipping reflectors）in 1981.Inversion of velocity structure is a key problem in their studies because of high velocity of lower crust in volcanic margins and high velocity of marine sediments with gas hydrates.Marine gas hydrates and their seismic studies are summarized in this part.Studies of seismic velocity and elastic coefficient structure of hydrated sediments are useful for better understanding the distribution，amounts and formation mechanism of marine gas hydrates (https://www.daowen.com)
Key words：Marine gas hydrates Seismic Velocity
Originally Published in：Oceanography in china，2002，14，98～105
