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

采集了日本弧前、弧后深部油气藏卤水，对比了它们的卤水、溶解惰性气体和稳定同位素(δD和δ)。利用初始海相^&lt；129&gt；i/^&lt；127&gt；i=1.5×10；-12&gt；确定了弧后卤水的碘年龄为22-53 Ma。由于日本海的扩张始于25 Ma，停止于14 Ma，因此其碘年龄与日本弧的形成历史有很大的出入。我们发现深部卤水中的^&lt；129&gt；i/^&lt；127&gt；i与其构造环境无关。

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.