The Characteristics of Clay Minerals of the Eocene-Miocene Continental Strata in the Zhangshu-Guangchang Region,Jiangxi Province and its Paleoclimatic Significance
The Characteristics of Clay Minerals of the Eocene-Miocene Continental Strata in the Zhangshu-Guangchang Region,Jiangxi Province and its Paleoclimatic Significance
The study of climate-sensitive sediments from the Cenozoic in the South China Block indicates that the paleoclimate during this period generally experienced a transition from arid to humid conditions.However,there is a lack of detailed characterization regarding the specific evolutionary process of this climate transition.This paper focuses on the Eocene to Miocene continental strata in the Zhangshu-Guangchang area of Jiangxi Province in eastern South China,systematically conducting whole-rock mineral content and clay mineral X-ray diffraction(XRD)analyses.The results show that the clay minerals are primarily composed of illite and illite-smectite mixed layers,with relative contents of illite ranging from 7%to 63%,kaolinite from 0%to 93%,chlorite from 0%to 17%,and illite-smectite mixed layers from 0%to 63.2%.According to the combinations and relative abundance changes of clay minerals,along with previous research findings,it is suggested that the paleoclimate in this region change from relatively arid to semi-arid and semi-humid conditions during the Eocene to Miocene in the early Miocene.This understanding provides important references for the study of paleoclimate evolution in the South China Block.
关键词
华南地区/黏土矿物/古气候重建/古气候意义/始新世-中新世
Key words
the South China Block/clay minerals/paleoclimate reconstruction/paleoclimate significance/Eocene-Miocene