Rare Earth Element (Ree) Geochemistry and Genesis of Oil Shales Around Dağhacilar Village, Göynük-Bolu, Turkey

Abstract

The study area is located in the south of Dağhacılar village of Göynük town in Bolu Province, Turkey. This study is a pioneering work in Turkey on the genesis and environmental characteristics of oil shales and other shallow marine-type sedimentary rocks regarding their major and rare earth element contents. The abundances of SiO 2 , Al 2 O 3 , TiO 2 , K 2 O and Fe 2 O 3 decrease in the following order: claystone > oil shale > marl. CaO and MgO abundances are ranked in the decreasing order as follows: marl > oil shale > claystone. These results reveal the presence of two different genetic groups-detrital and marine. The same groups were also established in the correlation studies of elements. TOT/C and TOC contents of rocks observe the following order: oil shale > marl > claystone, and as a result of variations in redox conditions they also vary in a wide range. Total carbon and total organic carbon are positively correlated with the group representing clays and negatively correlated with CaO, MgO and MnO. That is why TOT/C and TOC are associated with clays. The positive correlations between some major oxides (e.g. SiO 2 , Al 2 O 3 , Fe 2 O 3 , TiO 2 and K 2 O) and REE might indicate that clays and iron oxy-hydroxyls play an important role in transportation and deposition processes. The only slight negative Ce and positive Eu anomalies and Ce/Ce* and Eu/Eu* values recorded in the depositional environment indicate low oxygenated and anaerobic (reducing) conditions.

Rare earth element contents of the Lusi mud: An attempt to identify the environmental origin of the hot mudflow in East Java – Indonesia

“…This type of rocks is usually more enriched in the REE [22,23] compared to arenaceous rock types [24,25]. So, this may be the case that the LREE is found to be abundant within the Lusi mud [26][27][28].…”

“…Seemingly, the negative Eu anomaly shows a typical Eu pattern of shales (Figure 8), that weathering processes of such rocks may contribute in the REE abundances [14]. The REE was mobilized during alteration processes, such that caused the argillaceous shales become enriched in the REE concentration [27,28]. The processes might take place within the ocean-basin floor [33,36,37], which is consequently ideal environment for the Lusi shale to form the REE.…”

Evaluation of the Hydrocarbon Potential, Mineral Matrix Effect and Gas-Oil Ratio Potential of Oil Shale From the Kabalar Formation, Göynük, Turkey

“…However, in Himmetoğlu oil shale these values reach respectively 4991.8 kcal/kg and 30.9% [6,7]. The geological setting and geochemistry of Göynük oil shale has also been the subject of numerous prior studies [2,[8][9][10][11]. The main aim of the present research is to provide a more realistic evaluation of the hydrocarbon potential of Kabalar oil shale by taking mineral matrix retention effect into account, using sedimentary basinscale sampling and applying the gas-oil ratio potential (GORP) factor presented by Dahl et al [12].…”