Cue Energy, partner of Ophir Energy in the Sampang PSC, located in the offshore East Java, reported on 7 December 2018 that the wildcat Paus Biru 1 has flowed at a maximum rate of 13.8 MMcfg/d of gas from a drill stem test (DST) over the 576 m â 605 m (MD) interval. The net gas pay zone is estimated to be around 29 m, which is from the primary objective target in the Mundu Formation. The gas was flowing via a 120/64â choke for a period of 55 minutes. Initial test result from the gas sample has shown a clean gas.  The initial DST flow rate was 11.2 MMcfg/d over a five-hour period through a 64/64â choke, at a pressure of 525 psi. Reportedly, the well was shut in for a total of nine days for pressure build up prior to reaching the maximum flow rate.  Ophir reported a cost of USD 15 million for the well, which has been plugged and abandoned as planned. The companyâs next step is to prepare a plan of development for the discovery to be submitted for approval.    On 4 December 2018, Cue announced the completion of the flow testing campaign on Paus Biru 1. Test results were not released due to pending confirmation from the operator and from Indonesian authorities.  Preparations for testing were underway as of 13 November 2018, according to Cueâs earlier announcement. Three DSTs were planned to be carried out over the primary objective, the Pliocene Mundu Formation, to assess reservoir extent and productivity. The testing programme was expected to be completed within approximately two weeks.  The well reached TD at 710 m on 3 November 2018. The initial planned total depth of 650 m TVDSS was extended due to formation observation. Logging while drilling has shown high gas readings in several zones within the target formation. Positive indications were also provided by further wireline logging and testing, which included fluid sampling and pressure data collection.  Paus Biru 1 was spudded in mid-October 2018, using COSLâs âHai Yang Shi You 937â J/U rig. The rig reached the drilling location around 6 October 2018. Drilling operations were ongoing on 18 October 2018, with the 30â conductor installed to 105 m. At the time, drilling of the 26â hole was expected to commence on or around 20 October 2018.  Paus Biru 1 tested a four-way dip structure closure, targeting the Pliocene Mundu Formation, analogue to the Wortel and Oyong producing gas fields. Secondary objective was the Paciran Limestone Member. The initial plan was to conduct up to two DSTs in case of significant hydrocarbon indications during drilling and logging.  The Paus Biru structure is located approximately 27 km east of the Oyong gas field. Typical water depth in the area is less than 50 m.   After closing acquisition of the PSC from Santos on 6 September 2018, Ophir confirmed that drilling of Paus Biru 1 would take place in late 2018. The company has identified the Paus Biru prospect as a near field exploration target, with high chance of success. The drilling program was expected to last around 15 to 30 days.  In case of success at Paus Biru 1, a horizontal development well will be drilled at a later stage and tied-in to the Oyong field and Grati onshore gas processing facilities. Geotechnical and geophysical site surveys were conducted to determine the final well location, in parallel with sourcing for a drilling rig for the upcoming drilling campaign.  In late June 2018, the asset sale from previous operator Santos to Ophir was reported to be ongoing, and this was understood to have a possible impact on the drilling program being delayed to early 2019. The initial search by Santos for a suitable jackup rig was not successful at the time, and a new rig tender will be required. After completion of the asset sale in early September 2018, Ophir may have accelerated the drilling plan, in line with the new corporate strategy to pursue near-field exploration with potential for near-term development.  The block is operated by Ophir with 45% interest. The other partners are Singapore Petroleum (40%) and Cue Energy (15%).   Partner Cue Energy reported in late May 2018 that drilling preparations were ongoing, after the completion of site surveys to identify the drilling location. In late April 2018, the operator was assessing well site location and was also in discussion with nearby operators for a potential rig sharing opportunity, while working on the procurement process. Drilling of Paus Biru 1 was approved by the joint venture partners in late December 2017.  On 25 October 2017, Santos was reportedly waiting for the joint venture approval for the Final Investment Decision (FID) on the well. The company has likely received approval for its site surveys in early Q4 2017. Paus Biru 1 was previously identified as the prospective target for a low-risk exploration opportunity, based on 3D seismic mapping with visible amplitude anomalies. In case of success, it could further extend production life of the block.  Santos agreed to sell its entire interests in the Sampang PSC to Ophir Energy on 3 May 2018. The sale is part of a larger transaction by which Santos intends to divest its Asian portfolio, comprising exploration and production assets in Indonesia, Malaysia, Vietnam and Bangladesh, for a total consideration reported by Ophir at USD 205 million pre-capital adjustments. The sale of Santosâ production assets (Sampang PSC, Madura Offshore PSC, and Block 12W in Vietnam) was closed on 6 September 2018 after approval from Ophirâs shareholders. The interest transfer is back dated with an effective date of 1 January 2018.  Background Information  The Sampang PSC was awarded to Santos (Sampang) Pty Ltd (45%) and partners Coastal Indonesia Sampang Ltd (40%) and Cue Sampang Pty Ltd (15%) on 4 December 1997 upon payment of bonuses totalling USD 1 million and with a firm work obligation of USD 12.155 million in three years and USD 39.555 million in 10 years. Partial relinquishments have reduced the block to 532.5 sq km. Santos' initial exploration effort was the acquisition of a 560km 2D seismic survey between 11 August and 30 August 1998.   Santos announced the commencement of gas production from the Wortel field, also located in the Sampang PSC, on 1 February 2012. The field is developed through two horizontal production wells and an unmanned wellhead platform tied-in to the Oyong field facilities via a 10km gas pipeline. Combined production from Wortel and Oyong is expected to be 90 TJ/d (84.9 MMscf/d of gas).   Gas produced from Wortel is sent to the processing plant of Grati, in onshore East Java, via the 60-km Oyong gas pipeline, and then allocated domestically to local electricity company PT Indonesia Power (at about 30 MMscfg/d) and to two regional government-controlled companies. The price for gas produced in the block, initially set at USD 2.14 per MMBtu, was revised to USD 5 per MMBtu in November 2011.  Oyong field  The Oyong field was discovered in mid-2001 after the drilling of the Oyong 1 well which encountered a 120m gas column in the Pliocene Mundu Formation, underlain by a 38m oil column. The Oyong 2 and 3 wells successfully appraised the field and confirmed its potential for economic development. The field produced first oil on 24 September 2007, and first gas on 2 October 2009.  Wortel field  Wortel gas field was discovered in September 2006 through drilling of Wortel 1 (W-ITB 1). The TD at the well reached 1,464 m with significant hydrocarbons found in the Lower Pliocene Mundu Formation limestone. Following the success of Wortel 1, Wortel 2 (W-ITB 2) was spudded in late-September 2006 with a TD of 1,421 m. It was later plugged and abandoned as dry hole. The company acquired 395 km of 2D seismic in 2007 in Q4 2007. The survey is intended to provide additional infill exploration data over the Wortel gas discovery and three nearby additional prospects.  Development wells, Wortel 3 (W-ITB 3) and Wortel 4 (W-ITB 4) were spudded in January 2012, drilled to a depth of 2,020m and 2,277 m respectively. Drilling was conducted using a COSL Boss rig with hook-up and commissioning work completed later in the same month.
Indonesia (South Madura Deep (East Java B.)) Oyong