The geology of Afghanistan is structurally complicated, consisting essentially of a succession of narrow northeast-trending terranes of continental fragments of Paleozoic to Tertiary age. These have moved northward, colliding obliquely with the Asian continental land mass. The last arriving fragment was the large Indian continental block. It docked obliquely, imparting much additional folding and faulting and causing changes in structural trends. The accreted blocks are separated by sutures along which ophiolites are present. The latter apparently are the only remnants of subducted oceanic crust, representing oceanic spaces of unknown widths.
Three principal areas of thick sedimentary rock are present in Afghanistan: 1) North Afghanistan basin in the north, 2) southwest Afghanistan drained by the Helmend River, and 3) Katawaz area on the southeast. The second and third of these areas are highly folded and faulted, and petroleum potential is negligable. They are not considered further here. Only the North Afghanistan basin has appreciable prospects for oil and gas. The sedimentary rocks of this basin extend northwestward into Turkmenistan and Uzbekistan, where they form the Amu-Dar'ya gas-oil province. See Internet Geology News Letters 22, 25, 42, 89, and 116.
Drilling began in Afghanistan in 1956, and the first discovery was the Angut oil field in 1959. The period from 1959 through 1966 saw 50 wildcats drilled in the basin, and three primarily gas fields were discovered: Etym-Tag in 1960, Khvajeh Gugerdak in 1961, and Khvajeh Bulan in 1964. Details of further exploration are lacking, but it appears that from 1966 to 1981 two additional small oil fields and one large gas field (Dzhar-Kuduk in 1971) plus at least two other small gas fields were discovered. Most of the discoveries have been restricted to the northwest part of the North Afghan basement high. By the beginning of 1974 discoveries of recoverable gas totaled 3.5 tcf and additional indicated reserves of 1.235 tcf. Recoverable oil reserves, probably including condensate, stood at about 80 million barrels.
Exploration in the adjacent Amu-Dar'ya gas-oil province of
Turkmenistan and Uzbekistan has been quite successful.
Dauletabad-Donmez gas field in Turkmenistan with perhaps
60 tcf of recoverable gas is but 40 km (25 miles) from Afghanistan.
Although exploration of the Amu-Dar'ya province appears to be
at least in an early stage of maturity, that in the Afghan counterpart
is not. The level of activity for an area of this size appears to be low.
Until the beginning of 1979 reportedly only 7700 km (4800 mi) of
seismic profile had been shot, and 292,109 m (958.364 ft) of
wildcat hole had been drilled. This is equivalent to a single rig
drilling over the course of 20 years. The success rate is only
8 percent. The status of exploration after the Soviet invasion
of 1980 is unclear.
Taken from Kingston and Clarke, 1995, Petroleum Geology
and Resources of Afghanistan: International Geology Review,
vol 37, p. 111-127, four maps, six play analysis summaries.
Copyright 2001 James Clarke. You are encouraged to print
out this News Letter and to forward it to others. Earlier News
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