Thermochronological and structural investigation accompanying LEGENDS: I - The morpho-tectonic evolution of Sri Lanka

传说中的热年代学和结构调查：I - 斯里兰卡的地貌构造演化

• 批准号: 16174513
• 负责人: Professor Dr. Frank Lisker
• 金额: --
• 依托单位: Fachgebiet Geodynamik der Polargebiete
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/16174513?language=en
• 关键词: Thermochronological; structural; investigation; accompanying; LEGENDS

The Phanerozoic geological evolution of Sri Lanka is poorly constrained since no tectonic and/or igneous processes are recorded, and no large-scale "Gondwanan" sedimentary deposits are preserved. To overcome this deficiency, our study will apply low-temperature thermochronological methods (fission track/ FT and (U-Th)/He analysis) and structural investigations along the transect of the deep seismic LEGENDS traverse across Sri Lanka. This approach links the upper crustal cooling/ denudation pattern with the structure of the crust beneath, allowing a detailed quantification and genetic interpretation of the regional Phanerozoic geological history and long-term landscape evolution. Specific topics of the project are (1) the long-term development of the topography; (2) the course of the Gondwana breakup between Madagascar,.India, Sri Lanka and East Antarctica, and the subsequent evolution of the Sri Lanka continental margins; (3) the dating of tectonic activities and their influence on denudation; (4), the establishment of the paleogeothermal gradient; (5) the deposition of Gondwana sediments in Sri Lanka, and the evolution of the respective basin; and (6) the analysis of the regional fault pattern.

斯里兰卡的显生宙地质演化受到很弱的约束，因为没有记录构造和/或火成岩过程，也没有保存大规模的“冈瓦纳”沉积矿床。为了克服这一缺陷，我们的研究将应用低温热年代学方法（裂变径迹/FT和（U-Th）/He分析）和沿斯里兰卡深部地震LEGENDS横断面的结构调查。这种方法将上地壳冷却/剥蚀模式与下地壳结构联系起来，从而可以对区域显生宙地质历史和长期景观演化进行详细的量化和遗传学解释。该项目的具体议题是（1）地形的长期发展； (2)冈瓦纳大陆在马达加斯加、印度、斯里兰卡和东南极洲之间的分裂过程以及随后斯里兰卡大陆边缘的演化； (3)构造活动测年及其对剥蚀的影响； (4)、古地温梯度的建立； (5) 斯里兰卡冈瓦纳古陆沉积物的沉积及各盆地的演化； (6)区域断裂模式分析。

项目成果

Thermochronological dating of brittle structures in basement rocks: A case study from the onshore passive margin of SW Sri Lanka

• DOI: 10.1029/2012jb009136
• 发表时间: 2012-10
• 期刊: Journal of Geophysical Research
• 作者: B. Emmel;F. Lisker;T. Hewawasam