洞穴石笋纹(壳)层层组类型研究

Study on Laminae or Lamella Groups and Types of Stalagmite in Caves

石笋是洞穴碳酸钙沉积的典型滴石类型 ,也是岩溶记录中最全面、最系统的古气候环境信息载体 ,随着高分辨率测年技术和测试方法的提高 ,它在重建古气候环境方面具有重要的意义。石笋沉积纹层的组合、厚度、粒度和层面构造等 ,是恢复成笋滴水动态及相关古水文条件的物质基础 ,其中不少古气候环境信息 ,具强烈直观感 ,聚集物证、形象地记录于石笋剖面中 ,易观测研究。通过大量石笋纵剖面观测和系统的同位素组成、微 (痕 )量元素、特征性纹层的分析研究 ,证实石笋沉积纹 (壳 )层具韵律性组合和沉积旋回性及其古气候环境显示。首次提出石笋具叠锥型、叠柱型、叠锥叠柱复 (组 )合型纹 (壳 )层组和连续性、旋回性、间断 (歇 )性叠复纹 (壳 )层层组类型的沉积构造 ,并阐述各自的特征。

Stalagmite is a typical dripstone shape of CaCO 3 in caves and the most comprehensive and systematical paleoclimate environment information carrier too. With advances of dating techniques and analytic methods with high resolution,it is of great significance in the paleoclimate environment reconstruction. The combination, thickness, grain size and bedding plane structure of depositional laminae in stalagmite are the material base to resume droping water trends of forming stalagmite and the related paleo-hydrological conditions.On the basis of the analysis and study of many stalagmite vertical profiles and systematic isotopic compositions ,trace elements and specific laminae, it has been demonstrated that stalagime sedimentary laminae have obvious rhythmic combination , sedimentary cycles and indication of paleoclimatic environments. It is firstly put forward that stalagmite is of lamina groups of cone in cone, cone and pillar, cone in cone and pillar combined types and with the sediment ary structures ,such as continuity,cycle, disconnected and compound lamina types. The paper discusses their indivitual charatersitics, trends of dropping and flow water and evolutionary characteristics of climatic environments.