Compaction history of Upper Cretaceous shale and related tectonic framework, Arabian Plate, Eastern Oman Mountains

2018 ◽  
Vol 11 (16) ◽  
Author(s):  
F. Mattern ◽  
A. Scharf ◽  
M. Al-Sarmi ◽  
B. Pracejus ◽  
A.-S. Al-Hinaai ◽  
...  
10.1144/m54.1 ◽  
2021 ◽  
Vol 54 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Andreas Scharf ◽  
Frank Mattern ◽  
Mohammed Al-Wardi ◽  
Gianluca Frijia ◽  
Daniel Moraetis ◽  
...  

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.


GeoArabia ◽  
2014 ◽  
Vol 19 (2) ◽  
pp. 107-132
Author(s):  
Mohammed Y. Ali ◽  
David J.W. Cooper ◽  
Michael P. Searle ◽  
Ali Al-Lazki

ABSTRACT Gypsiferous intrusions are exposed in road-cuts in the south-central Hawasina Window in the central Oman Mountains. They are located at lower structural levels in the allochthonous Hawasina Complex and lie along faults that cut Upper Cretaceous structures related to the obduction of the Semail Ophiolite and Hawasina Complex deep-water sediments onto the Arabian Plate. The intrusions form gypsiferous pods that are up to 200 m long, in which the gypsum occurs as a dark, fine-grained matrix that contains a pervasive network of anastomosing veins of gypsum and anhydrite. The intrusions contain abundant sub-angular to sub-rounded litharenites, and less common fragments of chert and fine-grained limestone. Although these clast types are undated, their petrographic characteristics suggest they originate from the local Hawasina (Hamrat Duru Group) country rock. Very well-rounded pebbles and cobbles of feldspathic litharenites, some of which show a well-developed cleavage, and rarer cobbles of well-rounded vein quartz appear to have come from the basement. Gravity investigations indicate salt diapirs are not present beneath the Hawasina Window. Instead, the gypsiferous intrusions are interpreted as having been brought up from depth during compression to form disconnected pods along deep-rooted faults, bringing with them small amounts of the basement country rock. Strontium isotope analysis and regional considerations, in particular the distribution, age and nature of other evaporite units on the eastern Arabian Plate, suggest the gypsum may have its origins in the Neoproterozoic (Ediacaran) to lower Cambrian Ara Group evaporites, perhaps from a previously unknown extension of the Fahud Salt Basin beneath the Hawasina thrust sheets.


GeoArabia ◽  
2001 ◽  
Vol 6 (3) ◽  
pp. 445-504 ◽  
Author(s):  
A.Ziegler Martin

ABSTRACT A series of 19 paleofacies maps have been generated for given time intervals between the Late Permian and Holocene to reconstruct the depositional history of the Arabian Plate. The succession of changing lithological sequences is controlled by the interplay of eustacy and sediment supply with regional and local tectonic influences. The Mesozoic paleofacies history of the Plate is, in its central and eastern portion east of Riyadh, strongly influenced by an older N-trending, horst and graben system that reflects the grain of the Precambrian Amar Collision and successively younger structural deformations. The late Paleozoic Hercynian orogenic event caused block faulting and relative uplift and resulted in a marked paleorelief. This jointed structural pattern dominated the entire Mesozoic and, to some extent, the Cenozoic facies distribution. The relationship between producing fields and the paleofacies maps illustrates the various petroleum systems of particular times and regions.


1971 ◽  
Vol 8 (1) ◽  
pp. 65-84 ◽  
Author(s):  
Grant A. Bartlett ◽  
Leigh Smith

Two wells drilled by Pan American in the Grand Banks of Newfoundland gave the first stratigraphic section of Cretaceous and Cenozoic age northeast of Long Island and the only Jurassic and possible Permian sections in the Atlantic Continental Margin of North America.Integrated analysis of lithic and faunal data showed a minimum of seven sequences present. These are Pleistocene, Middle and Upper Miocene, Intra-Eocene, Paleocene and lowest Eocene, Upper Cretaceous, Middle Cretaceous, and Neocomian in age.The rocks range from halite and anhydrite, of possible Permian depositional age, to limestones, in the Upper Jurassic, lower Upper Cretaceous, mid-Eocene and mid-Miocene, and sandstones, which dominate the Neocomian, Upper Eocene, and Middle Miocene. Variable proportions of shale and silty mudstone occur throughout.The microfaunas contain both Tethyan and Boreal elements, and suggest oceanic circulation changes, sea-floor spreading, or both.Depositional environments ranged from subaerial, for the quartz arenites, through very low-land, for stream and swamp deposits, to estuarine, lagoonal, bank and open-shelf warm-marine environments, in which were deposited fine sand to clay-size terrigenous sediment, or, in its absence, skeletal carbonates or lime muds. The first dominant cooling trend appeared in the Late Miocene.All erosional environments of the hiatal episodes appear to have been subaerial and humid.A salt dome intruded the Tors Cove well section, its last movement being in mid-Early Eocene.Periodic interregional tectonic oscillations produced the erosional and depositional episodes of the major baselevel transit cycles. Their total effect is a sedimentary wedge, thickening by preservation toward the continent's edge, and representing one-half or less of Upper Mesozoic and Cenozoic time.


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