8 July 2019, Uzbekneftegaz (UNG) reports another gas discovery in the North Ustyurt Basin (north-western Uzbekistan). Well Kushkair 1 has been drilled to a TD of 3,550 m and has tested gas with condensate at rates of up to 200,000 cu m/d (6.85 MMscf/d). UNG is continuing to test the well and expects to estimate of the discoveryâs reserves later in H2 2019.  Although UNG calls Kushkair a new discovery, the company drilled the first exploration well, Central Kushkair 1, not later than in the early 1980s. The well was drilled to a TD of 3,780 m and tested 50,000 cu m/d (1.7 MMscf/d) of gas from the Upper Carboniferous carbonates. The top Carboniferous in this well occurs at 3,548 m.  The Kushkair discovery is located in the south-western part of the North Ustyurt Basin, around 40 km south-west of the large Urga gas field.  Earlier this month UNG reported a âgiantâ gas discovery in Ustyurt, at Arslan-Surgil Janubiy, east of the major Surgil gas field. However, numerous exploration wells drilled in the basinâs Uzbek sector since in the 2000s have been unsuccessful or have resulted in minor discoveries, leading to several operators relinquishing their exploration acreage in the region (e.g. Gazprom, Petronas, Petrovietnam and the Aral Sea consortium (ASOC)).  Background Information  Most of the known gas fields in the North Ustyurt Basinâs Uzbek part have their reservoirs in Jurassic clastics, but gas pools in Paleozoic (Carboniferous) reservoirs have been found in four fields (Karachalak, Kokchalak, Urga Shimoliy and Chibiny). Oil and gas shows have also been registered in Paleozoic formations in several wells drilled in the Uzbek sector, e.g. Karakuduk, Barsakelmes Sharkiy, Karaumbet Shimoliy and others. A gas pool in Carboniferous limestones has been discovered at Tarymgaya in the neighbouring Daryalyk-Daudan Basin in Turkmenistan.  Two general play types are believed to be prospective in the Paleozoic (Pre-Upper Permian) formations - one is represented by Paleozoic buried hills, while the other is associated with reservoirs within the Paleozoic formations.  The Paleozoic buried hills play is controlled by secondary reservoir development at the top of Paleozoic formations because of processes such as leaching, weathering etc. A discovery in this play is known at Kokchalak where the reservoir is represented by weathered Lower-Middle Carboniferous limestones.  The gas/condensate discovery at Karachalak is believed to belong to the Intra-Paleozoic play. A gas pool at Karachalak occurs slightly deeper than the top Paleozoic. Hydrocarbons have been tested from Visean fractured and leached limestones.
Kushkair 1 (UzbekNefteGaz 100%) SW part of basin in NW of the country, TD=3550m gas-cond discovery, tested up to 6.85 MMcfg/d, ops continue. Despite the official notion of âdiscoveyâ, a well designated Central Kushkair was drilled in the early 80s, TD=3780m, 1,7 MMcfg/d on test from U. Carboniferous carbs.