Korea National Oil Corp. (KNOC) continued offering a farm-in opportunity in Block 6-1C and 6-1E, in the offshore Ulleung Basin, as of June 2020. KNOC owns 100% working interests in the both blocks and has extended its exploration rights in the both blocks for another 10-year exploration period since February 2020. One prospect named as Yellow Tai structure with an estimation of 3.5 Tcf of gas resources, is the drilling target for the company in 1H 2021.   KNOC announced in earlier February that the structure 'Bangeo' (name in Korean) located in the deep-water area with an average water depth of 1,000 m, about 40 km east of Donghae field, the only gas field in Korea, is expected to have resource reserves more than 10 times that of the Donghae field. (It is possibly talking about the same structure which is estimated to locate within the Block 6-1E).   In addition, the new structure is considered to have the same strata type as that is distributed in the Block 8/6-1N where KNOC with its partner Woodside Australia made a non-commercial discovery in 2015. In order to confirm the possibility, a large-scale 3D seismic survey was planned to be conducted initially in the first half of 2020, but has been deferred to 2021  Â   Background Information  Block 6-1C and 6-1E are the only exploration blocks in the vicinity of the Donghae Gas field, the only producing gas field in South Korea. The fields and discoveries in the blocks had reservoirs in the Miocene section, with traps related to anticlines, unconformity and stratigraphic variation. Older and deeper traps related to rifting, including normal faults and tilted basement fault-blocks, have not been tested.  Block 6-1C (6-1 Central), covering more than 2,000 sq km, contains the only two producing gas fields in South Korea, Donghae 1 and Donghae 2 (in the past was referred to as Gorae-8). Donghae-1, with recoverable reserves of around 190 Bcf and 3 MMbc, was brought into commercial production in November 2004. Donghae 1 field reached peak annual production of around 19 Bcf in 2010. In 2018, annual production was around 3Bcf, with daily average output of 10 MMcf/d. Production life is expected to be until 2021, with the field planned to be converted afterwards into an offshore storage facility.   Donghae 2 gas field is located 5.4 km southwest from the Donghae 1 gas field. Donghae 2 has estimated recoverable reserves of about 22 Bcf and it was brought onstream in July 2016. It was jointly developed by KNOC (operator, 70% interest) and Daewoo International (30% interest). The field reached a daily production of 22 MMcf/d in 2018.   Block 6-1E, covering about 1,300 sq km, contains two gas discoveries Dolgorae 2 and 3.   Dolgorae 2 was discovered in January 1989, discovery well Dolgorae 2 was drilled by Korea Petroleum Dev. Corp, one outpost well Dolgorae (Dolphin) 2A-1X was drilled in the same year. The discovery was estimated to have 75 Bcf of gas in-place.  Dolgorae 3 was discovered in 1987, discovery well Dolgorae 3 was also drilled by Korea Petroleum Dev. Corp, two outpost wells were drilled in 1988 as dry hole or oil/gas shows. The discovery was estimated to have 140 Bcf of gas in-place.
Korea National Oil Corp. (KNOC) continued offering a farm-in opportunity in Block 6-1C and 6-1E, in the offshore Ulleung Basin, as of June 2020. KNOC owns 100% working interests in the both blocks and has extended its exploration rights in the both blocks for another 10-year exploration period since February 2020. 