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与俯冲有关的构造沉降(约1 mm/a)而缓慢下沉，而由于多达60米厚的全新世泥浆(估计为1-4 mm/a)的压实而更快地下沉。两个相距35公里的沉没窑址，以及四到六个箱形窑址，在三角洲目前的海岸被侵蚀暴露，在退潮时可以进入。他们目前在海平面以下的确切位置将被测量，淹没的时间将通过对窑砖墙壁的发光测年来确定。结果被用来确定海岸的连续下沉或逐步下沉。很少有试点数据表明，东部最深的窑炉(涨潮以下约2米)在250年前曾被洪水淹没(用热释光测定陶器的年代)，因此，这些遗址将提供与现代三角洲直接相关的信息。此外，在被热带气旋完全淹没或摧毁之前，将对用于制陶或制盐的窑炉进行取样、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.