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对元谋盆地小河地区竹棚豹子洞箐剖面河湖相沉积物进行的磁化率及磁化率各向异性、κ-T曲线、非磁滞剩磁、(饱和)等温剩磁、低温磁学性质和磁滞回线等测试分析结果表明,沉积物的磁性矿物以赤铁矿为主,并含有少量磁铁矿;磁性矿物的含量和类型随沉积时间呈现有规律的变化,至少可以识别出8个磁铁矿含量较高的短期事件,这些短期事件对应的古气候条件可能与元谋盆地现今的亚热带干热气候相似.综合岩石磁学和岩石地层研究结果,认为元谋盆地晚中新世处于一个较为稳定的接受沉积区,以温暖湿润气候为主,间有短期的干热气候,为理解约8.1MaBP前后我国西南地区气候转型及古猿演化提供了较为丰富的古环境信息.
Magnetic susceptibility and magnetic susceptibility anisotropy, κ-T curve, non-hysteresis remanence, (saturation) isothermal remanence, low-temperature magnetic properties, and magnetic properties of the lacustrine facies sediments in the leeches of Dongzhu, Hysteresis loops and other test results show that the sedimentary magnetic minerals are mainly hematite and contain a small amount of magnetite. The contents and types of magnetic minerals show regular changes with deposition time, at least 8 The paleoclimate conditions corresponding to these short-term events may be similar to the current subtropical dry-hot climate in Yuanmou Basin.Based on the results of rock magnetism and lithostratigraphic research, it is concluded that the Late Miocene of the Yuanmou Basin was in a relatively Stable receiving sedimentary areas, mainly warm and humid climate, there is a short period of dry and hot climate, in order to understand about about 8.1MaBP before and after the climate change in Southwest China and the evolution of the ancient ape provides a more rich paleoenvironmental information.