Assessing the recent subsidence of the central coastal Delta of Bangladesh by dating submerged kiln

通过测定水下窑的年代来评估孟加拉国中部沿海三角洲近期的沉降情况

• 批准号: 189838835
• 负责人: Professor Dr. Till Hanebuth, Ph.D.
• 金额: --
• 依托单位: Department of Coastal and Marine Systems Science
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/189838835?language=en
• 关键词: Assessing; recent; subsidence; central; coastal

The delta of the Ganges‐Brahmaputra slowly subsides by subduction‐related tectonic subsidence (about 1 mm/a) and more rapidly due to compaction of the up to 60 m‐thick Holocene muds (estimated as 1‐ 4 mm/a). Two submerged kiln sites, 35 km apart from each other, with four to six box‐shaped kiln constructions are exposed by erosion at the current coast of the delta and are accessible during ebb tides. Their present exact position below sea level will be measured and the timing of submergence will be determined by luminescence dating of the kiln brick walls. The results are used to determine the continuous or stepwise subsidence of the coast. Few pilot data suggest the deepest eastern kiln (about 2 m below high tide) has been flooded 250 years ago (pottery dated by thermoluminescence) and, thus, the sites will yield information, which is of direct relevance for the modern delta. Furthermore, the kiln which were either used for pottery or for salt production will be sampled, documented and archived before their complete submergence or destruction by tropical cyclones.

恒河-雅鲁藏布江三角洲因俯冲相关的构造沉降（约1 mm/a）而缓慢下沉，并因高达60 m厚的全新世泥浆的压实（估计为1 - 4 mm/a）而更快地下沉。两个水下窑遗址，彼此相距35公里，有四到六个箱形窑建筑，在三角洲当前海岸的侵蚀中暴露出来，在退潮时可以进入。将测量它们目前在海平面以下的确切位置，并通过窑砖墙的发光测年确定淹没时间。其结果可用于确定海岸的连续或逐步沉降。很少有试验数据表明，最深的东部窑（约2米以下的高潮）已被淹没250年前（陶器的热释光测年），因此，网站将产生的信息，这是直接相关的现代三角洲。此外，将对用于制陶或制盐的窑炉进行取样、记录和存档，以防其被热带气旋完全淹没或摧毁。