QUATERNARY VOLCANIC ACTIVITIES IN SHANDONG PENINSULA AND NORTHERN PARTS OF JIANGSU AND ANHUI PROVINCES
Zheng Honghan Gao Weiming Zhu Zhaoyu Huang Baolin Lu Liangcai(Institute of Geochemistry (Guangzhou Branch), Academic Sinica, 510640) (Earthquake Analysis and Prediction Centre, State Seismological Bureau, Beijing)
Quaternary volcanic rocks often coexist with loess, as observed in the same geologic sections in the Shandong Peninsula and northern parts of Jiangsu and Anhui provinces. The development age of Shandong loess is close to that in the middle reaches of the Yellow River. Loess strata are of synchronous implication in the loess belt of North China. So the ages of volcanic activities can be estimated approximately from the stratigraphic relations between loess layers and volcanic rocks. The results of TL dating of the Quaternary volcanic rocks, baked layers and loess samples suggest that the Quaternary volcanic activity can be divided into 4 stages in the region studied, with the ages being 1.15-1.03, 0.86-0.72, 0.55-0.33 and 0.02 Ma B.P., respectively. The occurrence of tephra in the Shandong loess sections is possible due to multiple episodes of volcanism during the Quaternary time.