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活动断裂最新错动与地震事件的关系是重要的基础研究课题。文中选定郯庐断裂带泗洪县重岗山—王迁段,开挖大型探槽,识别编录晚第四纪以来变形和史前地震事件,分析其活动期次和特性。结果表明,郯庐断裂带重岗山—王迁段晚第四纪以来曾发生强烈的挤压逆冲活动,在重岗山表现为晚白垩世砖红色砂岩向西高角度逆冲于晚更新世黄褐色黏土之上,在王迁则表现为黄白色上新世砂岩向西逆覆于晚第四纪沉积之上,且存在部分张裂现象。通过14C测年分析,得到重岗山—王迁段的2次古地震事件,其年代依次为(11 755±45)~(10 525±45)a BP与(10 135±50)a BP。郯庐断裂带重岗山—王迁段晚更新世以来逆冲活动强烈,而且一直持续到全新世初期。
The relationship between the latest fault rupture and earthquake events is an important basic research topic. In this paper, we select the Wanggang section of Weigangshan-Wangqian, Sihong County, Tanlu fault zone to excavate large-scale exploration trenches, identify the deformation and prehistoric seismic events since the Quaternary of the Catalog, and analyze the periods and characteristics of the activities. The results show that there was intensive extrusion and thrusting activity in the Wanggang section of the Wangchuan-Lugan fault zone during the Late Quaternary. In the Late Cretaceous, the Cretaceous brick-red sandstone was thrust to the west at a high angle to the Late Pleistocene On the yellow brown clay, Wang Qian was characterized by a yellow-white upper Pleistocene sandstone overlying the late Quaternary sediments westward, with some cracks. Through the 14C dating analysis, two paleoearthquakes from the Konggangshan-Wangqian Member were obtained, and the ages were (11 755 ± 45) ~ (10 525 ± 45) a BP and (10 135 ± 50) a BP. The Tanlu fault zone, the Rehobuhan area, was characterized by strong thrusting activity since the late Pleistocene in the Wangqian segment and continued into the early Holocene.