In spite of this, and a subsequent worldwide decline in trade as the thirties began, he kept his faith in the future. This was largely because of several strange black patches of a rough bituminous substance that had long been observed in different parts of the desert. The Ruler and his people were well aware of the activities of the oil prospectors in neighbouring Bahrain, Saudi Arabia and Iraq - to say nothing of the Anglo-Persian Oil Company's successes in southern Iran.
Kuwait Oil Company, Ltd. Discovery of Oil While drilling continued in Bahrain, attention turned to Burgan and to the recommendations about this area in the technical report of Cox and Rhoades. Geological surveys were carried out and the company drilled in this area through and early It was here, on 22nd February that oil was discovered.
Moreover, this oil was under such pressure and in such quantity that it blasted through the wellhead valve with such force that it could not be controlled. It was a gush that was "difficult to hold". Lack of sufficient drilling mud to block the hole meant that other means had to be immediately found to block the well. Donald Campbell, then Chief Accountant, finally located a 60 feet long wooden pole in the town bazaar and that served as a temporary stopper. That was how, at 11 a.
Some define it as the region between India and Egypt, in which case it has been aptly designated by the United Nations as Western Asia. Other definitions also add North Africa or central Asia.
These ten countries together have an area of 5. This article synthesises our knowledge about this question and briefly describes the geological factors for the abundance of oil in the Middle East. The tectonic framework of the Middle East is divided into 1 Zagros fold-and-thrust belt, 2 Unstable Arabian shelf, and 3 Stable Arabian shelf. The Arabian continental plate, which collided with the Asian plate along the Bitlis-Zagros suture during the Eocene, is still converging with Asia at a rate of 1.
Global measurements of relative plate motions of Arabia with respect to Eurasia show higher velocities of 2. This continental collision gave rise to the Zagros orogen and its Cenozoic foreland basin, which was superimposed on the Paleozoic-Mesozoic Tethys shelf basin.
The cumulative thickness of sediments in the region reaches up to 12 km. The western and southern boundaries of the Arabian plate are bounded respectively by the Red Sea and Gulf of Aden rifts.
These Neogene continental rifts have separated Arabia from Africa, and are further pushing Arabia against Asia. The rift-shoulder uplifts have outcropped the Precambrian rocks part of the Nubian-Arabian shield along the Red Sea and are capped at places by rift-related volcanic rocks.
The Proterozoic-Cambrian transition at about Ma opened a new chapter in the geologic history of the Middle East with far-reaching implications for petroleum resources of this region. After a long history of ocean subduction and micro-continental collision along the north-eastern margin of Africa from about Ma to Ma, the basement rock of the Middle East the Nubian-Arabian shield was consolidated.
This event, together with some other collisions, assembled the supercontinent of Gondwana in the southern hemisphere, comprising Africa, India, Australia, Antarctica, and South America. At this time the Middle East was positioned on the north-facing passive margin of Gondwana. Throughout Paleozoic and Mesozoic times, the Middle East was a locus of sedimentation over a long and wide shelf affected, from time to time, by sea level changes. As Gondwana consolidated at the turn of the Cambrian, microorganisms and marine species also rapidly evolved and diversified, thus enriching marine sediments with organic carbon necessary for hydrocarbon generation.
This sequential development of Tethys took place as continental fragments successively broke away from the Gondwana margin and drifted northward to join the paleo-Asian continent.
The opening of each Tethys ocean was accompanied by extensional tectonics which, in turn, created continental rifts during the Infracambrian Ediacaran-Cambrian transition period , the Ordovician, and the Permian in the Middle East. These rift basins added favourable sites for petroleum generation in the region. At the end of the Palaeozoic, Gondwana merged with Laurasia to form the largest supercontinent ever, Pangea.
It was also during this time that Proto-Tethys closed and Neo-Tethys began opening. In the Late Cretaceous, Neo-Tethys began to subduct beneath the southern margin of paleo-Asia along the Anatolia-Iran-Tibet margin and shrank in size until the ocean completely disappeared in the Eocene and gave way to a foreland basin in front of the rising Bitlis-Zagros-Himalayan mountains.
The Phanerozoic sedimentary succession in the Middle East is up to 12,m thick and can be divided into three mega-sequences:. This tectonic-sedimentation framework impacted on petroleum generation and accumulation in the Middle East in ways unique to this region. Movement of the Kuwait-Persian Gulf area throughout Phanerozoic times. Also shown are major geologic events relevant for sedimentation history of the region. Compiled from various sources including Beydoun Episodes, June Paleogeographic modeling of Paleozoic continents and atmospheric circulations Judith Parrish, AAPG Bulletin , June shows that during the Silurian the Middle East was close to a major upwelling current that enriched the sediments with exceptional amounts of organic matter.
Some of these classic source rocks include the Sargelu Formation Middle Jurassic, m thick in type locality , Garau Formation Lower Cretaceous, over m thick , Gadvan Formation Lower Cretaceous, m thick , and Kazhdomi Formation Middle Cretaceous, m thick in the Zagros Basin of south-west Iran, and age-equivalent limey-shale formations in Iraq and the Persian Gulf areas.
To explain these rich source rocks we need to consider the position and extent of the Neo-Tethys shelf during Jurassic and Cretaceous times. Neo-Tethys was then located close to the warm, organic-rich Equator; it possessed a broad 2,, km-wide shelf and a length of at least twice that Murris, AAPG Bulletin , May Moreover, Neo-Tethys was triangular in shape, pointed thinning toward the west; it was thus a partly enclosed basin with its wide shelf oriented almost west-east, and in a favorable position to benefit from organic-rich sedimentation processes and high stand sea-levels.
The triangular Neo-Tethys Ocean had a wide and long shelf, restricted on the western end but open to the east.
The idea of trade winds and Neo-Tethys ocean currents concentrating nutrients for planktons comes from Irving et al. Canadian Journal of Earth Science, Jan. These conditions, which favoured the eposition of organic-rich source rocks and thick carbonates, prevailed in the Middle East until the latest Cretaceous. In Late Jurassic-Early Cretaceous times, Gondwana was split apart, and as rift volcanism and sea-floor spreading developed, ocean temperatures rose and ocean waters were enriched with nutrient elements from volcanic outpourings along mid-ocean ridges and continental margins or island arcs.
Oxygen-isotope analyses of marine limestones have shown that Ma was a time of severe global warming due to a rapid increase in atmospheric carbon dioxide concentrations mainly from increased volcanic activities. This is consistent with sequence stratigraphic evidence for sea-level maxima in mid-late Cretaceous times.
Warm climate, high-stand seas and increases in the nitrogen-phosphorus-carbon contents of oceans, in turn, led to a profuse radiation of plankton populations - a key factor in the organic richness of marine sediments laid down during that period.
Neo-Tethys most benefited from these events and the Middle East was in the right position at the right time. Based on their sedimentary facies distributions, R. Murris has divided the Mesozoic carbonates of the Middle East into two categories.
The second category is differentiated carbonate shelf or platform carbonates, which were deposited under transgressive conditions, where differentiation is marked with starved sediment-deficient euxinic basins separated by high-energy margins from carbonate-evaporite platforms. Rich source rocks are included in the second category. Stratigraphy and petroleum source-reservoir rocks of selected areas in the Middle East.
In the Middle East, however, carbonates were deposited on a long and wide shelf from the Permian to the Paleocene with insignificant hiatus. Even after the Arabia-Asia collision, carbonate sedimentation continued in a very shallow marine environment an ongoing process in the Persian Gulf.
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