Block 4 is located within the onshore oil rich Sabatayn (Marib-Shabwa) basin, it is bounded to the south by Block 70, to the west by Block 69, to the north by Blocks 86/S2 and to the east by Block 3, Area 1998 km2. Exploration and Development were carried out by Russian companies, 1983 – 1991. Three fields were discovered, the commercial production started during 1987.
A 201-km of 20” oil pipeline linked the production facilities with Al-Rudhum Terminal on Gulf of Aden. Nimir Petroleum Company (NPC) signed Block4 PSA in 1991, NPC subcontracted Arco as operator. The oil production peaked to 10,000 BOPD during 1992-1994, the field was shut down on May 1994, NPC resumed production on 1996, NPC handed over its assets to Ministry of Oil and Minerals (MOM), Yemen on January, 2001.
In April 2001, YICOM was assigned as the new PSA holder and carried out the field operations until May 2008. KNOCYL appointed as operator up to Oct 2013 under Joint Operation Agreement with YICOM which is now 100% PSA holder and Block 4 operator.