Chapter 1 Introduction and tectonic framework

Andreas Scharf,Gianluca Frijia,Frank Mattern,Mohammed Al-Wardi,Bernhard Pracejus,Wilfried Bauer,Daniel Moraetis,Ivan Callegari

doi:10.1144/m54.1

Abstract

AbstractThe extraordinary outcrop conditions provide a unique opportunity to study the geology and tectonics of the Oman Mountains, which record a geological history of more than 800 million years. We provide a summary of the geological evolution of the Oman Mountains with the emphasis on the Jabal Akhdar and Saih Hatat domes. This Memoir comprises seven chapters. This first chapter summarizes the former studies and the tectonic framework. This is followed by a comprehensive description of all geological formations/rock units (Scharf et al. 2021a, Chapter 2, this Memoir) including the famous Semail Ophiolite, the fault and fold pattern (Scharf et al. 2021b, Chapter 3, this Memoir) and the overall structure (Scharf et al. 2021c, Chapter 4, this Memoir). Chapter 5 (Scharf et al. 2021d) explains the varied tectonic evolution of the study area, ranging from the Neoproterozoic until present, while Chapter 6 (Scharf et al. 2021e) contains the conclusions and a catalogue of open questions. Finally, Chapter 7 (Scharf et al. 2021f) provides two over-sized geological maps (1 : 250 000 version available online) and a correlation chart, providing an overview of the geological units/formations. This volume is of interest for all geoscientists, geoscience students and professionals studying the Oman Mountains on the surface as well as in the subsurface because it represents a comprehensive and detailed reference.

Highlights

The Oman Mountains at the northeastern margin of the Arabian Plate display an impressive geological record in terms of phenomenological diversity and significance since the Precambrian
We concentrate on the eastern part of the Oman Mountains from the western tip of the JAD to the eastern end of the SHD
To assist the international research community, we provide a newly compiled geological map of the eastern part of the Oman Mountains with the JAD and SHD in order to standardize the compiled tectonic units within a single map

Summary

Tectonic framework

The eastern part of the Arabian Peninsula (Fig. 1.1) was the site of several tectonic events. Callegari et al (2020) documented the first evidence of the Cadomian Orogeny in northern Oman. This event is documented by tight to isoclinal folds with an amplitude of a few to tens of metres in the Hajir Formation of the JAD. The age of deformation was at some time after deposition of the Fara Formation and before the Angudan event, that is, between c. The Cadomian Orogeny was followed (and probably overlapped) by the Neoproterozoic–Early Cambrian East African Orogeny (sensu Stern 1994), resulting in the Angudan Unconformity that coincides with the final stage of the East African Orogeny Some authors use the Introduction and tectonic framework em an Fault Syst Minab-Zend

Thrust front of Semail Ophiolite pes Qalhat Sur

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