The Ongole coastal dunefield (OCD) is about 20 km long and 2.5 to 3 km wide, and is located to the east of Ongole town between the mouth of the Paleru river in the south and a small creek in the north. Much of the dunefield lies 3–5 m above sea level with some large dune ridges reaching 10–12 m. The area landward of the dune field consists of an extensive marsh. Optically stimulated luminescence (OSL) dating of 12 sub-surface sediments from three sites near the western edge of the dunefield gives almost concurrent age of 5.1±0.4 ka. Radiocarbon dating of one shell from a similar location also corroborates the OSL age while the age of another shell taken closer from the modern shoreline gives a date of 3.29±0.5 ka. The age of the deposits and morphology of the dunefield indicate that it was probably initiated on some form of barrier system at the end of the Holocene transgression.

中文翻译：

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表征印度东南部的 Ongole 沿海沙丘：地层和时间限制

Ongole 海岸沙丘（OCD）长约 20 公里，宽 2.5 至 3 公里，位于 Ongole 镇以东，南面是巴勒鲁河河口，北面是一条小溪。大部分沙丘位于海拔 3-5 m 处，一些大型沙丘脊高达 10-12 m。沙丘地向陆的地区是一片广阔的沼泽地。来自沙丘西部边缘附近三个地点的 12 个地下沉积物的光学受激发光 (OSL) 测年几乎同时给出了 5.1±0.4 ka 的年龄。来自相似位置的一个贝壳的放射性碳测年也证实了 OSL 年龄，而距离现代海岸线更近的另一个贝壳的年龄给出了 3.29±0.5 ka 的日期。