Serpentinite Rocks of Mawat Ophiolite Complex, Northeastern Iraq, Beetwat Village: 1-Petrography and Diffractometry

Abstract

The Mawat ophiolite complex is of Cretaceous period as a residue of oceanic crust covers about 200 km2, Northeastern Iraq.. The serpentinite rocks are exposed as a diapir in the northeastern suture Zagros zone of Iraq near Beetwat village, The field study and petrography reveal two types of serpentinite, the shear and massive, with three serpentine varieties. The serpentinite rocks are affected by secondary processes such as diagenesis, metamorphism and hydrothermal alteration in different degrees. Some common Textures in these rocks are pseudomorphic such as mesh or sieve textures, glass hour and bastite texture. Nonpsedomorphic textures appear also in these rocks such as interpenetrating fibrous, interlocking textures. Mineralogically, the massive serpentine minerals are lizardite and chrysotile that affected by recrystalization and replacement of lizardite. The (XRD) analysis explain that the serpentine is composed of lizardite, chrysotile, antigorite, in addition to amphibole minerals (anthophyllite and tremolite), chlorite talc, and opaque minerals as chromite.