ÇAĞRILI KONUŞMALAR / KEYNOTES Invited Speeches ... - TPJD

Rare Earth Elements Enrichments of Organic Matter Rich Rocks in the South
of Dağşeyhler Village
Okay Çimen 1 , Ali Sarı 2 , Şükrü Koç 3
1 Ankara University, Graduate School of Natural and Applied Sciences, Ankara
2 Ankara University, Faculty of Engineering, Department of Geological Engineering, Ankara
3 Ankara University, Faculty of Engineering, Department of Geological Engineering, Ankara
Rare earth element content of samples which are collected from the study area were
determined by ICP-MS method. REE distrubitions are as follows, claystone:63.94-176.41
(120.17) ppm, carbonaceous claystone 43.19-85.97 (63.68) ppm, marl:2.96-74.25 (33.80) ppm
and oil shale:26.46-79.28 (50.68) ppm. REE contents show a decreasing trend from claystone
to marl samples. This situation can indicate that REEs were transported with clay minerals to
the depositional environment. REE contents of oil shale are higher than marl, however lower
than claystone. LREE/HREE ratios relatively are high in all lithologies. These ratios are as follows,
claystone: 4.14, carbonaceous claystone: 3.24 marl: 2.87 and oil shale: 2.83. 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 REE contents of all
samples normalized to UCC and PASS values, weak Ce anomalies and positive Eu anomalies
were determined in all samples. Weak Ce anomaly indicates partially lower oxygen conditions,
whereas positive Eu anomaly indicates presence of Ca-bearing minerals.
Keywords: Rare earth elements, oil shale, major element, organic matter
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