Petrographical and Sedimentological Study of Balambo Formation at Northeastern Iraq

Abstract

This study was carried out for Balambo Formation (Valanginian  - Turonian). Area of study alocated within Azmir anticline at Sulaimaniya area at northeastern Iraq. From petrography study, it was found that the radiolaria forming the main skeletal such as; Novixitus mclaughlini, Archaeodictyomitra simplex, Xitus spinosus, Paronaella ewingi, Cryptamphorella conara, Rhopalosyringium hispidum, Crucella messinae and Vitorfus morini  .  While  the planktonic foraminifera such as; Globigerinelloides bentonensis, Globigerinelloides ultramicus,   Planoheterohelix globulosal, Hedbergella (Asterohedbergela), Planomalina buxtorfi, Ticinella praeticinensis and Calcispheres in second order. The ground mass formed of gray to brown micrite. The rocks effected by diagenetic processes with many types like silicification, recrystallization, cementation, and dissolution. According to Microfacies analysis study, the recognized main facies are tow: lime mudstone and lime wackstone. These facies divided into four submicrofacies: radiolarian lime mudstone submicrofacies, calcispheratic lime mudstone submicrofacies, radiolarian lime wackestone submicrofacies and Globigerinelloids lime wackestone submicrofacies. Based on facies and petrographic studies, its deposited within deep sea (Bathyal Zone) .