青藏高原水热活动沉积物的精细研究

The Tibetan Plateau Crust is thicker than most other regions of the Earth, but the hydrothermal activities here are abundant close to its strength as much as the modern volcanic areas. Widely distributed ancient travertine show that once there were widely more intense hydrothermal activity on the plateau. As sign of tectonic activities and hydro-geological activities, ancient travertine deposits had saved a unique record of the hydrogeological system. Taking some hydrothermal activities and ancient travertine deposits as a case study, combining with the research results of the liquid, gases, the characters of hot travertine deposits, such as geochemistry, isotope, neotectonic age will be studied according micro layers. By comparing environmental isotopes and its backgrounds, researching influence factors of environmental isotopes in modern travertine sediments, the main influence factors of environmental isotopes in will be analyzed. Studying trace and rare elements, isotopes value such as 87Sr/86Sr、26Mg、44Ca, analyzing their mantle or crust source characteristics, The unique intrinsic mechanism of hydrothermal activities in Tibetan Plateau should be studied. Furthermore, the roles of hydrothermal activities in the earth's carbon cycle should be revealed.

青藏高原地壳厚度远大于地球上其他大多数地区，但是青藏高原的热水活动极其发育，其强度不亚于近、现代火山活动区。广泛分布的的古泉华说明高原上曾经广泛发育更为强烈的水热活动。泉华沉积物作为构造活动和水文地质活动的标志，较好地保存了水文地质系统的独特记录。项目以青藏高原水热活动及其遗迹为研究实例，结合液体、气体方面的研究成果，深入精细剖析温泉沉积物，研究其地球化学、同位素、新构造年龄等特征。通过环境同位素研究以及环境背景的精细对比研究，以及现代水热活动沉积物影响因素分析研究，阐明泉华中环境同位素的主要影响因素。通过微量、稀土元素以及87Sr/86Sr、26Mg、44Ca等同位素分析其中可能的幔源或壳源特征，探讨青藏高原水热活动独特的内在机制，进一步揭示高原水热活动在地球碳循环中扮演的角色。