Investigation on the correlated mechanisms between deep groundwater flow and material transport in the different plate tectonic fields

收集了日本弧前、弧后深层油气储层的卤水，对比了其<129>I/ <127>I、<36>Cl/Cl、溶解惰性气体和稳定同位素（δ d和δ <18>O）。我们利用初始海相^<129>I/^<127>I比值1.5×10^<-12>，确定了弧后地区卤水的碘年龄为22-53 Ma。由于日本海的扩张开始于25ma，结束于14ma，所以碘年龄与日本弧的形成历史有很大的差异。深海相的^<129>I/^<127>I比值与构造环境没有关系。

We collected brines from deep oil and natural gas reservoirs in forearc and backarc settings in the Japan arc and compared their ^<129>I/^<127>I, ^<36>Cl/Cl, dissolved noble gases and stable isotope (δD and δ^<18>O). We determined iodine ages of 22-53 Ma for brines from the backarc region by using an initial marine ^<129>I/^<127>I ratio of 1.5×10^<-12>. Because expansion of the Japan Sea started 25 Ma and ceased by 14 Ma, there is a great discrepancy between the iodine ages and the history of the formation of the Japan arc. We found no relationship between the ^<129>I/^<127>I ratio in deep brines and their tectonic settings.