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

恒河-雅鲁藏布江三角洲由于俯冲相关的构造沉降而缓慢下沉（约1毫米/年），而由于高达60米厚的全新世泥的压实作用（估计为1 - 4毫米/年），其下沉速度更快。两个相距35公里的水下窑址，有四到六个箱形窑建筑，在三角洲当前海岸的侵蚀下暴露出来，在退潮时可以进入。它们目前在海平面以下的确切位置将被测量，淹没的时间将由窑砖墙的发光年代测定来确定。这些结果被用来确定海岸的连续或逐步下沉。很少有试验数据表明，最深的东部窑（涨潮以下约2米）在250年前被淹没（通过热释光测定陶器年代），因此，这些遗址将提供与现代三角洲直接相关的信息。此外，用于制陶或制盐的窑炉将在它们完全淹没或被热带气旋破坏之前进行取样、记录和存档。

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.