EP 21-5-1 completed in early August 2020 without result reported.  CNOOC â Shenzhen spudded a new-field wildcat EP 21-5-1 in the Pearl River Mouth Basin, South China Sea, on 20 July 2020. The well is situated at a water depth of approximately 90 m area located in the Enping Sag and near EP 20-4 and EP 20-5 discoveries, with targets in the Mio-Oligocene clastic play. âNanhai 2â S/S is used for the drilling operation.     In November 2018, CNOOC completed EP 20-4-1 with oil in this area. In January 2019 an appraisal well, EP 20-4-2, was completed with success.     CNOOC announced in 2019 mid-year review that Enping 20-5-1 encountered oil pay zones about 93 m thick, and that the discovery was expected to become a "mid-sized" oil field, defined as having recoverable resources of 2.5 MMcm to     In March 2020 CNOOC announced that the successful appraisal of Enping 20-5 and Enping 20-4 confirmed a "reserves base of mid-to-large oil fields".    In addition, two wells drilled in 2019 around the EP 20-4/5 discovery, EP 21-2-1 and EP 21-3-1, without result reported.    Background Information    In the past few years, about 10 discoveries have been made in the Enping Sag, the most significant ones are EP 24-2, EP 18-1 and EP 23-1 fields cluster, with reservoirs from Miocene to Oligocene sands.     To date, five fields have been brought onstream successively since 2014. The latest onstream field in the area is EP 23-1 fields cluster (together with EP 23-2 and EP 23-7), which started commercial production in November 2016 with initial flowing 5,597 bo/d from three wells. The cluster together with Enping 18-1 (on stream Sep 2016) were tied-into the Enping 24-2 facilities, the later on stream in 2014.     In 2018, CNOOC completed EP 15-2-1 and EP 10-2-1, in the Enping Sag with both penetrating oil-bearing zones. The EP 10-2-1 and EP 15-2-1 discoveries, together with existing EP 15-1 discovery, are expected to be a medium size cluster/joint development. EP 15-1 discovery was made in 2016 in the Enping Sag.     The Miocene to Oligocene reservoirs are the most significant reservoirs in the PRMB, mainly predominated by sandstones and carbonates of the Lower Miocene Zhujiang Formation, sandstones of the Middle Miocene Hanjiang Formation, and sandstones of the Upper Oligocene Zhuhai Formation. These sandstones were mainly deposited as massive fluvial sands and as deltaic channel and tidal bars with good reservoir properties.    In addition, CNOOC has completed a few wells in the Enping Sag for the last five years.    EP 9-4-1 was completed in early February 2020 with result unreported.    In 2019 quite a few wells drilled with result unreported, such as EP 10-4-1, EP 20-1-1, EP 20-2-1, EP 20-7-1 and EP 24-3-1d.     In 2018 CNOOC completed EP 12-2-1d with result unreported.     In 2017 CNOOC completed EP 23-11-1d and EP 18-6-1 with result unreported.     In 2016 CNOOC drilled EP 11-4-1 and EP 16-1-1 with result unreported.
(Pearl River Mouth B.) EP 21-5-1 nfw, located in Yangjiang 18, operated by CNOOC LTD (100%), completed in early August 2020 without result reported. 