Petrography, heavy mineral study and tectonic setting of Walash Naopurdan Series Sandstones, Qalander area, Northeastern Iraq

Abstract

The Petrography and Heavy mineral study of Walash-Naopurdan Series Sandstone (Middle-Late Eocene) at Qalander area is carried out. Thin section study of twenty seven samples showed that these sandstones consist of quartz, feldspar, rock fragments (lithics), matrix, and cement. The rock fragments are of sedimentary, igneous, and metamorphic types as an indication of multiple source rocks originated from the complex thrust zone of northeastern Iraq. The Heavy mineral analysis also showed different types, dominated by opaques and transparent minerals as a further indication of multiple source rocks. The main constituents of the studied sandstones (quartz, feldspar, rock fragment and matrix) are used in their classification which showed that the sandstones are of lithic greywacke type.The provenance indicating triangular diagrams (QtFL and QmFLt) showed that the Walash-Naopurdan Series Sandstone is of recycled orogen sources shared between transitional, mixed, dissected and transitional arcs tectonic settings. These represent a complex convergent boundary with dissected transitional volcanic arc which was subjected to uplift and erosion.