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用吉林1号陨石的43块样品确定了吉林陨石的宇宙线和铀裂变径迹密度的深度剖面。这个深度剖面基本上反映吉林陨石第二(4π)照射阶段记录的银河宇宙线径迹。由钻孔A和B的径迹测定结果,求得吉林陨石通过大气层时的平均烧蚀厚度分别为11±4cm和14±5cm;在第一(2π)照射阶段,钻孔A“顶部”的最小屏蔽深度约为30cm。大约在小于0.4 Ma前,由于短期受热事件的影响,使通过大气层前母体的15—20cm厚的表层中的核径迹退火,由此导出母体近表面区的观测径迹密度与理论预期值发生偏离。
43 samples of Jilin No.1 meteorite were used to determine the depth profile of cosmic ray and uranium fission track density of Jilin meteorite. This depth profile basically reflects the galactic cosmic ray track recorded at the second (4π) irradiation stage of Jilin meteorite. According to the track measurements of boreholes A and B, the average ablation thickness of Jilin meteorites passing through the atmosphere is 11 ± 4cm and 14 ± 5cm respectively. During the first (2π) irradiation stage, the “top” The minimum shielding depth is about 30cm. Approximately less than 0.4 Ma ago, the observed nuclear track in the 15-20 cm thick superficial layer passing through the precursors of the pre-atmosphere was annealed due to the effects of a short-term thermal event, resulting in the observed track density of the near-surface region of the maternal body corresponding to the expected theoretical value Deviation.