Evolution of Exploration Concepts in Arabia

Abstract

Exploration concepts progress by evolution, driven by mutations of ideas as data is acquired, analyzed and communicated. The evolutionary rate is dictated by the rate of data acquisition and analysis (exploration effort, focus and expenditure). The steady evolution of ideas is occasionally punctuated by revolution, causing the bloom of new concepts. The targets of exploration in this region evolved progressively from shallower to deeper formations. The first oil discoveries were in Cretaceous reservoirs in Bahrain (1932) and Kuwait (1938), followed by the discovery of prolific Jurassic oil reservoirs in eastern Saudi Arabia (1938) and Qatar (1940) onshore, and progressed to offshore areas in the Gulf starting with Safaniya (1951). Exploration during the 20th century targeted anticlinal structures, which were found initially at their outcrop, then chased underground with structural drilling, nonseismic and seismic surveys. Stratigraphic traps followed with limited contribution to production. Deeper nonassociated gas was initially discovered in Bahrain in the Permian Khuff carbonates in 1947, and culminated in the discovery of the supergiant North field in 1972. These discoveries were not commercially viable until the growth of demand from industry, utilities, and LNG exports. During the 1980s, gas discoveries in Paleozoic sandstones in Saudi Arabia (Ghawar), and Oman's salt basins, along with increasing demand for gas, focused exploration on deeper sandstone targets. The last three decades have witnessed major success in gas exploration, which went hand in hand with revolutionized understanding of the Carboniferous “Hercynian” orogeny and its impact on hydrocarbon trapping geometries and of reservoir distribution. The unconventional reservoir revolution in the Middle East started with the intra-salt carbonate/silycilite play in Oman, and is rapidly spreading to target gas in shales, tight sands, and carbonate mudstone source rocks throughout the region. Exploration for oil and gas faithfully served the economic development of the region and improved the welfare of its citizens. Its contribution to the world economy needs no discussion.

AAPG Datapages/Search and Discovery Article #90194 © 2014 International Conference & Exhibition, Istanbul, Turkey, September 14-17, 2014