Geochemistry of Layered Ultramafic Rocks in J.C. Pura Schist Belt, Dharwar Craton, Karnataka, India  

作　　者：S. Santhosh B. G. Dayanand B. C. Prabhakar S. Santhosh;B. G. Dayanand;B. C. Prabhakar(Department of Geology, Bangalore University, Bangalore, India)

机构地区：[1]Department of Geology, Bangalore University, Bangalore, India

出　　处：《Open Journal of Geology》2023年第2期189-202,共14页地质学期刊（英文）

摘　　要：The Jayachamarajapura schist belt in western Dharwar craton, southern India, is predominantly an ultramafics dominant terrain. These rocks have been extensively metamorphosed and altered to serpentinite. The komatiite nature of ultramafics is conspicuous. In most of the areas of the belt these ultramafics are massive in nature. However, some of the ultramafic units show layered nature. But, their outcrops are encompassed within the massive komatiitic bodies. These komatiitic ultramafics are predominantly Mg-rich in nature. The layered rocks are also Mg-rich, and their field setting and geochemistry suggest their intermittent occurrence as sills, during the differentiation of peridotitic magma. The layered rocks, which have been intensely serpentinisation show homogenous nature. They are almost wholly made of serpentine with occasional relics of pyroxene. Secondary carbonate mineral is often noticed. Their higher MgO content indicates Mg-rich ultramafic magmatism during Archaean orogeny.The Jayachamarajapura schist belt in western Dharwar craton, southern India, is predominantly an ultramafics dominant terrain. These rocks have been extensively metamorphosed and altered to serpentinite. The komatiite nature of ultramafics is conspicuous. In most of the areas of the belt these ultramafics are massive in nature. However, some of the ultramafic units show layered nature. But, their outcrops are encompassed within the massive komatiitic bodies. These komatiitic ultramafics are predominantly Mg-rich in nature. The layered rocks are also Mg-rich, and their field setting and geochemistry suggest their intermittent occurrence as sills, during the differentiation of peridotitic magma. The layered rocks, which have been intensely serpentinisation show homogenous nature. They are almost wholly made of serpentine with occasional relics of pyroxene. Secondary carbonate mineral is often noticed. Their higher MgO content indicates Mg-rich ultramafic magmatism during Archaean orogeny.

关 键 词：Western Dharwar Craton Layered Sequences KOMATIITE J.C. Pura Belt 

分 类 号：P58[天文地球—岩石学]