REE geochemistry of the carbonate rocks from the 4th member of the Shahejie Formation in the Dongying depression,Shangdong

The carbonate rocks from the 4th member of the Shahejie Formation occur as interbeds in the continental clastic rocks in the Dongying depression,Shangdong.The REE geochemistry of the representative carbonate rock samples is characterized by ΣLREE > ΣMREE > ΣHREE,MREE enrichment relative to HREE,no Ce/Ce^* negative anomaly,Y/Ho ratios ranging from 25.5 to 34.1,La/La^* ratios ranging from 0.99 to 1.21,and negative correlation of Y/Ho vs.La/La^*.The similarity to the geochemical signatures of the lacustrine carbonate rocks indicates a lacustrine origin of the carbonate rocks in the study area.