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对中国大陆科学钻探(CCSD)主孔0-4000的岩心样进行了裂变径迹年龄测定。在不同深度共测定了38个样品的磷灰石裂变径迹年龄,磷灰石的裂变径迹年龄数据分布在98．6～3．2Ma之间,年龄值的变化规律总体上是随钻孔深度的增加而逐渐减少,地表样的磷灰石裂变径迹年龄是87．1Ma,至3899m深处则为3．2Ma,基于磷灰石中裂变径迹的退火特征,反映出地壳温度随深度的增加而增加的规律。年龄值随深度的变化,也有若干波动,尤其是1550～2450m之间的这部分岩心,在年龄随深度变化的趋势上是不连续的,这部分岩体可以认为是一个重要的构造作用带。根据年龄．深度关系和约束径迹长度的分布特征,对超高压变质岩体的后期折返机制进行了探讨。
Fission-track dating of core samples from main hole 0-4000 of China Scientific Drilling (CCSD) was carried out. The apatite fission track age of 38 samples was measured at different depths and the fission track age data of apatite were distributed between 98.6 and 3.2 Ma. The variation rule of age was generally as follows: The depth of the apatite apatite fission track is 87.1Ma, while that of the surface apatite is 3.2Ma at the depth of 3899m. Based on the annealing characteristics of the apatite fission track, it shows that the crustal temperature varies with the depth The increase of the law and increase. There are also some fluctuations in the age value with depth. In particular, this part of the core between 1550 and 2450m is discontinuous in the trend that the age changes with depth. This part of the rock mass can be regarded as an important tectonic zone. According to age. Depth relationship and constrained track length distribution characteristics of the UHP metamorphic rock after the reentry mechanism were discussed.