A5 Well - what we know todate8 Jul 2020 16:07
It's day 13 since the G50 rig arrived on site ready to replace the cracked link so can't be far off, we'll probably see some drilling fluid removal having to be done from the last sidetrack to boot during testing.
Looking forward to a 19mm choke setting next week? :- )
From the 25 June, 2020 RNS
''Deep Well A5
Deep Well A5 was spudded in July 2013, and drilled to a total depth of 4,442 meters with casing set to a depth of 4,077 meters to allow open-hole testing. Core sampling revealed the existence of a gross oil-bearing interval of at least 105 meters from 4,332 meters to at least 4,437 meters.
As noted above the well was difficult to drill with a salt layer of approximately 130 meters with high temperature and high pressure encountered at the lower depths. The extremely high-pressure in the well required the use of drilling fluids with a high density (2.16 g/cm3). Removing this high density drilling fluid to allow testing was problematic but was eventually completed sufficiently to allow an extended flow test.
In December 2017, using a choke setting of 19 mm, the well tested for 15 days at an average rate of 3,800 bopd before the flow reduced by debris in the well fell to 1,000 bopd leading to the well test being suspended.
Following two ultimately unsuccessful side-tracks a third side-track from a depth of 3,976 meters was completed in November 2019. On 31 December 2019, the well started to flow initially at a rate of 1,500 bopd using a 12 mm choke,
Given our experiences in 2017, our priority was to keep the well flowing by maintaining a good level of pressure. This required the choke setting to be reduced to just a few mm, which in turn quickly reduced the flow of oil. The unrecovered drilling fluid used in the original well and each of the three side-tracks further restricted the flow of oil from the well.
Accordingly, in February 2019, after 40 days of unassisted oil flows, the well was closed to allow work to remove excess drilling fluid which was restricting the flow rates and therefore any calculation of reserves. To date some 30 tonnes of excess drilling fluid has been removed using coil tubing equipment.
Our G50 rig is now on site to replace a cracked link in the tubing, following which we will once again attempt to get the well to flow at rates expected of a deep, high pressure well.''