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Quaternary volcanic rocks often coexist with loess,as observed in the same geologic sections inthe Shandong Peninsula and northern parts of Jiangsu and Anhui provinces.The development age ofShandong loess in close to that in the middle reaches of the Yellow River.Loess strata are ofsynchronous implication in the loess belt of North China.So the ages of volcanic activities can be es-timated approximately from the stratigraphic relations between loess layers and volcanic rocks.The re-sults of dating of the Quaternary volcanic rocks,baked layers and the TL dates of loess samples sug-gest that the Quaternary volcanic activity can be divided,into 4 stages in the region studied,with theages being 1.15-1.03,0.86-0.72,0.55-0.33 and 0.02 Ma B.P.,respectively.The occurrence oftephra in the Shandong loess sections is possible due to multiple episodes of volcanism during theQuaternary time.
Quaternary volcanic rocks often coexist with loess, as observed in the same geologic sections inthe Shandong Peninsula and northern parts of Jiangsu and Anhui provinces.The development age ofShandong loess in 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 es-timated approximately from the stratigraphic relations between loess layers and volcanic rocks.The re-sults of dating of the Quaternary volcanic rocks, baked layers and the TL dates of loess samples sug-gest that the Quaternary volcanic activity can be divided into 4 stages in the region studied, with theages being 1.15-1.03, 0.86-0.72, 0.55-0.33 and 0.02 Ma BP, respectively. the occurrence oftephra in the Shandong loess sections is possible due to multiple episodes of volcanism during the Quaternary time.