Major Oxides Geochemistry of Paleoproterozoic Malehra Chert Breccia Formation and Associated Sandstones of Bijawar Basin, Madhya Pradesh, India

The major oxides analysis of chert breccia and associated sandstone exposed around Bijawar and Bada Malehra town was investigated to infer the provenance and tectonic setting of these sediments. The lithology analyzed encompasses chert breccia and sandstone, which are located in the Malehra Chert Formation of the lower Moli subgroup within the Bijawar Group. The Malehra Formation is composed of variegated chert, massive chert, chert breccia, sandstone, and conglomerate, with trivial impure dolomite. The major oxides chemistry results of sandstones manifest high SiO2 (>90%), high K2O/Na2O (>1) and Al2O3/(CaO+Na2O) ratios and low Al2O3/SiO2 ratio and low Fe2O3(t) + MgO content with average Chemical index of alteration(CIA) value of 67.4 suggesting that these clastic sediments were deposited in a passive margin setting from a moderately weathered felsic source rock. Petrographic analysis illustrated, the sandstone arenitic character with the low matrix content (<15%) and predominance of quartz grains observed. The major elemental analysis of chert breccia infers that high ratio of SiO2/ (SiO2 + Al2O3 + Fe2O3) with average value of 0.95, Al/ (Al + Fe) ratio with 0.412 average value, 100 × Fe2O3/SiO2 vs. 100 × Al2O3/SiO2 and Fe2 O3/(100-SiO2) vs. Al2O3/(100-SiO2) illustrations indicate pelagic to continental margin setting for the deposition of these sediments.