Premier Oil PLC, whose Belut Laut-1 exploratory well on the Tunu block off Indonesia is to be plugged, said the well has confirmed the potential for hydrocarbons in the Oligocene section in the Nam Con Son basin.
The well went to the planned total depth of 4,948 m. Oil shows with high gas readings were reported from 4,740 m throughout a gross 155-m Oligocene sandstone interval, but logs indicated that the sandstones at this depth were of poor porosity.
Premier said the subsurface interpretation will be refocused to prospects at shallower depths where good reservoir properties are preserved updip from proven source rocks. Premier has identified at least five such prospects in the Tuna acreage and in adjoining Block 07/03 off Vietnam and plans to drill the first in the second half of 2012.
Meanwhile, the CS-N2P development well in Block 12W intersected the shallow part of a previously undrilled fault terrace to the northwest of Chim Sao field. Logging while drilling data indicate the well encountered a 20-m oil column in an independent closure in good quality Upper Dua sandstones. The plan is to appraise this new accumulation as a tieback opportunity via the CS-N1P development well.