Taxonomical and Biogeochemical Investigation of Elements in Holocene Mollusk Shells in the South and Southwestern Marmara Basin,Turkey

Concentrations of some heavy metals and trace elements such as Cr, Ga, Ni, Zn, Mo, Cu, Pb, Yb, Y, Nb, Ti, Sr, Ba, Mn, Sc, Co, V, Zr, Fe, Al, W, Se, Bi, Sb, As, Cd in recent mollusk shells and factors affecting their distribution and deposits collected from various depths in the southern and southwestern parts of the Marmara Sea are investigated. The distribution of the elements in the shells is categorized into four groups. Of these, concentrations of 12 elements （As, Bi, Cd, Co, Ga, Mo, Nb, Sb, Se, Sc, W and Yb） are below zero [（0.053-0.79）×10^-6]; concentrations of seven elements （Cr, Ni, Pb, V, Y, Zr and Cu） are （1.0-6.0）×10^-6; concentrations of four elements （Ti, Mn, Ba and Zn） are 10- 20×10^-6; and concentrations of five elements （Si, Al, Fe, Mg and Sr） are （47.44-268.11）×10^-6. The taxonomic characteristics of the 29 elements were studied separately in mollusk shells such as Chamalea gallina （Linn6）, Pitar rudis （Poli）, Nassarius reticulatus （Linn6）, Venerupis senescens （Coocconi）, Mytilus galloprovincialis （Lamarck）, Mytilaster lineatus （Gemelin in Linne） and Chlamys glabra. It was found that, in mollusk taxonomy, the elements have unique values. In other words, element concentrations in various mollusk shells depend mainly on the taxonomic characteristics of mollusks. In various bionomic environments different element distributions of the same species are attributed to the different geochemical characters of the each environment. Data obtained in this study indicate that the organisms are the most active and deterministic factors of the environment.     

铀在近代海洋生物中的积聚

本文研究的目的是确定软体动物对于铀在海洋生态系统中的分布所起的地球化学作用。对取自里海、日本海、马尔马拉海、爱琴海、黑海、地中海、波罗的海和印度洋的近代软体动物贝壳进行了生物地球化学研究,这些贝壳的物理、化学、地理和地球化学特征各不相同。本次研究中,分析了9个腹足类和54个双壳类不同种的贝壳以记录铀在不同季节层中的变化。季节层是由软体动物在整个生命过程中季节性的碳酸盐—有机相生成的。研究中使用的贝壳主要分3层:上(外)棱柱层,中棱柱层,内(珠母)层。此外,条件许可时,将贝壳性的头部、中部和下部分别进行分析,并且还计算出相对     

Organic Material and Trace Elements of Bituminous Rocks in the Ozank(?)y Field,Ankara,Turkey

Bituminous rocks in the Ozank(?)y(Ankara) field are different from those of the Paleocene- Eocene Mengen and Güineytepe(Bolu) regions in metal enrichment levels.Organic carbon(C_(org)) content of organic material-rich rocks in the Ozank(?)y(Ankara) field is 3.66-40.72% wt averaging 14.34%.The dominant organic materials are algae/amorphous accompanied by minor amount of herbaceous material(The dominant kerogen type is Type-Ⅰwith a limited amount of Type-Ⅱkerogen.). The bituminous rocks in the Ozank(?)y field are enriched in heavy metals such as Ni,Mn,As and Cr.In comparison with the average enrichment values of elements,Ni,Mn,As and Cr in bituminous shales of the Ozank(?)y field are as about 4.38,14.93,10.90 and 5.58 times as average values.The average concentrations of these heavy metals are also as high as 215×10~(-6),828×10~(-6),58.54×10~(-6),and 148×10~(-6) respectively.In addition,sorption properties of clay and organic materials are also important for metal enrichments in the bituminous shales.     

Organic Material and Trace Elements of Bituminous Rocks in the Ozankiiy Field, Ankara, Turkey

Bituminous rocks in the Ozankoey （Ankara） field are different from those of the Paleocene- Eocene Mengen and Giineytepe （Bolu） regions in metal enrichment levels. Organic carbon （Corg） content of organic material-rich rocks in the Ozankoey （Ankara） field is 3.66-40.72% wt averaging 14.34%. The dominant organic materials are algae/amorphous accompanied by minor amount of herbaceous material （The dominant kerogen type is Type-I with a limited amount of Type-Ⅱ kerogen.）. The bituminous rocks in the Ozankoey field are enriched in heavy metals such as Ni, Mn, As and Cr. In comparison with the average enrichment values of dements, Ni, Mn, As and Cr in bituminous shales of the Ozankoey field are as about 4.38, 14.93, 10.90 and 5.58 times as average values. The average concentrations of these heavy metals are also as high as 215× 10^-6, 828 × 10^-6, 58.54 × 10^-6, and 148 × 10^-6 respectively. In addition, sorption properties of day and organic materials are also important for metal enrichments in the bituminous shales.     

Taxonomical and Biogeochemical Investigation of Elements in Holocene Mollusk Shells in the South and Southwestern Marmara Basin, Turkey

Concentrations of some heavy metals and trace elements such as Cr,Ga,Ni,Zn,Mo,Cu, Pb,Yb,Y,Nb,Ti,Sr,Ba,Mn,Sc,Co,V,Zr,Fe,Al,W,Se,Bi,Sb,As,Cd in recent mollusk shells and factors affecting their distribution and deposits collected from various depths in the southern and southwestern parts of the Marmara Sea are investigated.The distribution of the elements in the shells is categorized into four groups.Of these,concentrations of 12 elements(As,Bi,Cd,Co,Ga,Mo,Nb, Sb,Se,Sc,W and Yb)are below zero [(0.053-0.79)×10~(-6)];concentrations of seven elements(Cr,Ni, Pb,V,Y,Zr and Cu)are(1.0-6.0)×10~(-6);concentrations of four elements(Ti,Mn,Ba and Zn)are 10- 20×10~(-6);and concentrations of five elements(Si,Al,Fe,Mg and Sr)are(47.44-268.11)×10~(-6).The taxonomic characteristics of the 29 elements were studied separately in mollusk shells such as Chamalea gallina(Linné),Pitar-rudis(Poll),Nassarius reticulatus(Linné),Venerupis senescens (Coocconi),Mytilus galloprovincialis(Lamarck),Mytilaster lineatus(Gemelin in Linné)and Chlamys glabra.It was found that,in mollusk taxonomy,the elements have unique values.In other words, element concentrations in various mollusk shells depend mainly on the taxonomic characteristics of mollusks.In various bionomic environments different element distributions of the same species are attributed to the different geochemical characters of the each environment.Data obtained in this study indicate that the organisms are the most active and deterministic factors of the environment.     

Organic Material and Trace Elements of Bituminous Rocks in the Ozank(o)y Field, Ankara, Turkey

Bituminous rocks in the Ozank(o)y (Ankara) field are different from those of the Paleocenecontent of organic material-rich rocks in the Ozank(o)y (Ankara) field is 3.66-40.72 % wt averaging 14.34%. The dominant organic materials are algae/amorphous accompanied by minor amount of herbaceous material (The dominant kerogen type is Type-Ⅰ with a limited amount of Type-Ⅱ kerogen.).The bituminous rocks in the Ozank(o)y field are enriched in heavy metals such as Ni, Mn, As and Cr. In comparison with the average enrichment values of elements, Ni, Mn, As and Cr in bituminous shales of the Ozank(o)y field are as about 4.38, 14.93, 10.90 and 5.58 times as average values. The average concentrations of these heavy metals are also as high as 215 × 10-6, 828 × 10-6, 58.54 × 10-6, and 148× 10-6 respectively. In addition, sorption properties of clay and organic materials are also important for metal enrichments in the bituminous shales.     

Biogenic Accumulations of Uranium in Recent Seas

The objective of this study is to determine the geochemical role of molluscs in the distribution of uranium in the marine ecosystem. Biogeochemical studies are carried out on recent mollusc shells from the Caspian Sea, Sea of Japan, Sea of Marmara, Aegean Sea, Black Sea, Mediterranean Sea, Baltic Sea, and Indian Ocean, which differ from each other in terms of physical, chemical, geographic, and geochemical characteristics. In this study, nine Gastropoda and fifty-four Pelecypoda shells of different species are analyzed to document variations of uranium in seasonal layers, which were formed by the seasonal carbonate-organic phase of molluscs during their entire lives. Shell used in this study principally comprises three layers: upper (outer) prismatic, middle prismatic, and inner (mother-of-pearl) layers. In addition, when possible, the head, the middle, and the lower parts of the shells are used for analyses separately. Also, the biological accumulation rate values for each different mollusc species rel