Petrophysics, gamma radiation

Petrophysics is about the physical properties of rocks. The properties investigated are mainly the rock's magnetism, density and radiometry. The porosity of rocks has also been investigated, but to a very limited extent. The product Gamma radiation contains data from field measurements at exposed bedrock from observed rocks in Sweden. Gamma radiation is often used to help characterize and classify rocks and for building materials there are norms and guidelines that describe limits for such radiation. Monitoring and knowledge of gamma radiation in rock is important for mining and quarrying, but also for laying up and deposition. Since gamma radiation measurement assesses levels of radioactive isotopes, it provides genetic and time information via the status of the decay chain. Despite the fact that the ionizing radiation is strongly attenuated by only a few centimeters thick soil cover, and that the majority of the ground surface is also covered by soil material, measurements of gamma radiation on rocks are a powerful tool for interpreting surface-covering radiation measurements. In addition, material transport follows weathering processes, and glaciation epochs follow patterns that are documented and mapped in quaternary geology.岩石物理学（Petrophysics）是研究岩石物理属性的学科。其所研究的核心属性主要包括岩石的磁性、密度与放射特性。尽管也曾针对岩石孔隙度开展过相关研究，但相关探索的范围十分有限。伽马辐射（Gamma radiation）数据集包含了瑞典境内露头基岩中观测岩石的野外实测数据。伽马辐射常被用于辅助岩石的表征与分类，针对建筑材料亦有相关规范与指南对该类辐射的限值作出了规定。对岩石中伽马辐射的监测与认知，对于采矿、采石作业以及岩土铺筑与物料堆存工作均具有重要意义。由于伽马辐射测量可表征放射性同位素的活度水平，其可通过衰变链的状态提供岩石的成因与年代信息。尽管电离辐射仅需几厘米厚的土壤覆盖层即可被大幅衰减，且绝大多数地表均被土壤覆盖，但对岩石的伽马辐射测量仍是解读地表覆盖层辐射测量结果的有力工具。此外，物质运移遵循风化作用的演化规律，而冰期的发育模式则可在第四纪地质学研究中被记录与绘制成图。