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f Rare Earth Elements (REEs) Enrichments in the Upper Cretaceous Haymana Formation (Haymana/ANKARA)
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 18th International Petroleum and Natural Gas Congress and Exhibition of Turkey, May 2011, cp-377-00081
Abstract
Rare earth elements content of the samples which are collected from the study area were determined by ICP-MS method. REEs content of various rock litholigies are as follows; carbonaceous claystone 77.81-167.05 (111.07) ppm, sandstone 99.05-127.49 (110.81) ppm, marl 7.69-84.48 (49.45) ppm. REEs content show a decreasing trend from carbonaceous claystone to marl samples. Because of increasing of the clay contents, concentration of REEs increase in the all samples. With increasing of clay content in the examined samples are observed that increasing of LREE/HREE ratio either. These ratios are as follows ; sandstone samples 4.14, carbonaceous claystone 3.23 and marl 2.82. This situation indicates that REEs were transported with clay minerals to depositional environment and clay minerals control the concentrations of the light rare earth elements. When REEs contents of all the samples normalized to UCC and PASS values, negative Ce anomalies and positive Eu anomalies were determined. Negative Ce anomalies indicate oxygen conditions in the depositional environment, whereas the samples which have got increasing positive Eu anomalies indicate decreasing of energy in the environment and presence of Ca-bearing minerals.