ZAGROS OROGENY

Zagros Orogeny

[Name of Writer ]

Abstract

Geologically, Iran can be divided into two part, The Zagros folded belt and the rest of the country. In the Zagros folded belt quiet conformable sedimentation continued from Cambrian to Pliocene time. Only gentle tectonic movement and salt diaprisim affected this belt before the late Tertiary. This tectonic movement led sediments to fold into a series of anticlines and synclines. A GPS-derived velocity model shows present-day convergence rates between Arabia and Eurasia of 19-26 mm per year The aims of this paper are thus to provide a review of our present knowledge of the Zagros orogeny and the detailed links between the Zagros build-up and the overall Neo-Tethys ocean history or with the rest of Iran. The respective contributions of subduction and collision stages to the formation of this orogenic belt are also mentioned.

Table of Contents

Introduction1

Background1

Significance of the Study2

Aims of the Study2

Research Objectives2

Literature Review3

History and Evolution of Zagros Mountain4

Morphotectonic divisions of the Zagros5

The High Zagros Thrust Belt (Zagros Imbricate Zone)5

The Zagros Simply Folded Belt (ZSFB)6

The Fars region is dominated by Jurassic6

Methodology8

Qualitative Research8

Research Strategy8

Data Sources9

Surveys9

Research Design10

Research Method10

Data Collection Method10

Qualitative Research11

Discussion12

Geological context12

The Persian Gulf-Mesopotamian Lowlands12

Salt Diapirism in the Zagros12

Seismotectonics in the Zagros14

The Major Zagros Reverse Fault (MZRF)16

The Main Recent Fault (MRF)16

The High Zagros Fault (HZF)16

The Mountain Frontal Fault (MFF)17

The Zagros Foredeep Fault (ZFF)18

References21

Appendix23

Zagros Orogeny

Introduction

From SW to NE, and from bottom to top, the following areas come into Zagros range: The Zagros Folded Belt (ZFB) makes up the currently active accretionary wedge of the Zagros collision. The Sanandaj-Sirjan Zone (SSZ), located to the north of the Main Zagros Thrust (MZT). The Urumieh-Dokhtar Magmatic Arc (UDMA) is interpreted as a sub ductionrelated arc that has been active from Late Jurassic time to the present. In fact, several other adjacent domains located in the far field of Zagros deformation must be considered. These are the Alborz Mountains, KopetDagh, Central Iran and Sistan regions. The history of the Zagros orogeny largely overlaps with the deformation history of most of Iran since the Jurassic.

Background

The Zagros represents the culmination of the collision between the plates of Arabian and Eurasian tectonic. Zagros Mountains extend for more than 2000 kilometers from Turkey to the southwest of Iran. Movements orogenic began during the Late Cretaceous with the location of units ophiolitic on the margin of Arabia. From the continuous Upper Cretaceous convergence between two tectonic plates produced a decrease resulted in folds and thrust system that eventually formed the folding as we know it. This folding, however, occurred mainly during the Miocene. The outermost part of the Zagros Mountains of present outcrops high quality enabling very detailed studies of the structure and allow the collection samples for dating the syntectonic sediments that will determine the age of the tectonic deformation. The absolute age of Neogene sediments was determined for the first time during the course of the doctoral thesis of Stephane Homke in our group.

The calculated age, however, was only for the most frontal folds Zagros System. Dating folds system is very important for the ...