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Israel lies on the eastern shore of the Mediterranean and extends southeastward to the Gulf of Aqaba, the eastern arm of the Red Sea. The country is 250 miles long, 70 miles wide at its widest part, and has an area of 8,040 square miles. The present population is 1,570,000, with a high proportion of craftsmen and skilled workmen. The government is a parliamentary democracy. No point in the country is more than 23 miles from a surfaced road, few are more than 10 miles.
The southern half of the country is the Negev, a desert of high ridges and wide sand washes, bordered on the east by the barren trench of Wadi Araba and on the west by Sinai (Egypt). North of the Negev are the Judean and Ephraim mountains, a broad arch bordered on the east by the Dead Sea-Jordan Valley and with a steep west flank. The steep flank flattens into a foothills belt that merges westward into a coastal plain along the Mediterranean. The coastal plain is interrupted by the uplift of Mt. Carmel near Haifa, then continues through Galilee to the northern border. North of the Ephraim Mountains and Mt. Carmel is the Emeq, a northwest-southeast plain that extends from the coastal plain to the Jordan. North of the Emeq is Galilee, a highland area of ridges, mountains, and narrow val eys, with the Upper Jordan Valley on the east and the coastal plain on the west.
Structural differences divide the country into eight geologic provinces: (1) the Dead Sea-Wadi Araba graben, with faulted anticlines and half-anticlines along its borders and with possible salt domes in the valley itself; (2) the Negev, striped with long anticlinal folds on which are numerous domes; (3) the foothills belt, with surface evidence of anticlinal folding both oblique and parallel with the Judean-Ephraim arch; (4) the coastal plain, in which gravity surveys indicate anticlinal folding; (5) the Carmel uplift, a horst on which are two anticlines; (6) the Emeq, a graben in which the downfaulted folding and faulting of the older rocks are concealed beneath Recent and Pleistocene sediments, with a few Miocene and perhaps Plio-Pleistocene volcanoes near the eastern end; (7) the U per Jordan rift valley, the northern extension of the Dead Sea-Wadi Araba graben; and (8) the Galilee highland, a faulted area of tilted blocks, grabens, and horsts with many faulted anticlines and half-anticlines. Parts of the country lie in a ninth province, the Judean-Ephraim arch, but these are so small that they are here included in adjoining provinces.
The country lies between the pre-Cambrian Arabian Shield on the southeast and the Tethys or Eastern Mediterranean geosyncline on the west. The area has been a coastal region since Cambrian time, with frequent ingressions and regressions of the sea. The result is a succession of deep-water, shallow-water, littoral, estuarine, lagoonal, lacustrine, and terrestrial sediments, with many unconformities, wedge-outs, and changes in facies.
Sedimentary beds range from early Paleozoic to Recent and fall into three main divisions: (1) upper clastic, Recent through Oligocene, terrestrial with numerous marine members; (2) middle calcareous, Eocene through Upper Cretaceous, almost entirely marine; (3) pre-Upper Cretaceous, interfingering terrestrial sandstones and marine beds, with the marine percentage increasing northward
and westward from about 15 per cent in the southernmost Negev to 70 per cent or more in the northwestern Negev and thence northward.
Total sedimentary thickness is probably 3,000-7,500 feet in the southern Negev, 7,500-12,000 feet in the northeastern Negev, and 10,000-20,000 feet in the northwestern Negev and the rest of the country.
Bituminous beds are widespread, a few of them high in organic content. Gas and asphalt eruptions in the Dead Sea have been famous since the dawn of history. Asphalt impregnations and live seeps are numerous in the rifts bordering the Dead Sea graben. In the southern coastal plain is a gas seep with asphalt impregnation and a sulphur deposit. A water well near Saqiya in the central coastal plain got a substantial flow of gas in Pliocene beds at 517 feet. Small asphalt veins have been reported in the northern Negev, in the northern foothills belt, and in eastern Galilee. Asphalt has been mined intermittently for 100 years in Syria 14 miles from the northern Israel border. Farther away, but in beds that occur in Israel under similar structural conditions, oil and asphalt seeps are found n Lebanon and Turkey on the north; small oil fields with high saturations per acre have been found along both sides of the Gulf of Suez on the southwest.
Only one well has been drilled for oil in Israel. Located near Huleiqat in the southern coastal plain, it stopped at 3,464 feet, probably in the Cretaceous, leaving 7,000-16,000 feet of sediments undrilled. Dip readings indicate that it was off structure at depth. A well at El Khabra in Sinai, 8 miles from the Israel border, drilled to 10,282 feet and stopped in the Jurassic without encountering oil. Dip readings indicate that it too was off structure at depth. Several thousand water wells have been drilled throughout the country, less than 100 as deep as 1,000 feet; only the Saqiya well encountered oil or gas. Ten core holes have been drilled for geologic information in the Dead Sea area; two of them drilled through thick impregnations of live asphalt. Otherwise the country is virgin territory waiting to be tested.
Each of the geologic provinces has oil possibilities, but they differ in character and degree. Structural and stratigraphic traps probably exist in the Upper Jordan Valley and the Emeq, but they will be hard to find. In the faulted anticlines and blocks of the Galilee highland and the Carmel uplift the chances are fair to good. Somewhere beneath the Dead Sea-Wadi Araba area must be large oil and gas accumulations; despite the difficulties of search in a rift valley, the possibilities of the province are good. The Negev has numerous structures worth testing. The foothills belt and coastal plain are folded; further work should reveal structural highs underlain by thick sections, predominantly marine. Stratigraphic traps are indicated for the Negev, the foothills belt, and the coastal pl in. In both structural and stratigraphic traps, the possibilities of these three provinces are good.
Thus the oil possibilities of two of the eight geologic provinces are obscure, of two are fair to good, and of four--comprising more than three-fourths of the country--are good.
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