The EFB D-24 well is located in the East Flour Bluff gas field and is designed to test four main J sands reservoirs and potential reservoirs as the primary target and 3 potential reservoirs in the deeper K sands, according to Flour Bluff partner Victoria Petroleum.
EFB D-24 is a relatively low-risk well which will test a four-way dip closure with 3P (proved plus probable plus possible) recoverable reserves of 17.5 BCF (billion cubic feet) of gas and additional potential for a further 14 BCF (total 31.5 BCF).
“Four of the reservoirs in this closure have already produced gas in old wells, but these wells were lost by engineering failure soon after production started,” said Victoria Petroleum.
“None of the old wells were fracture-stimulated and it is anticipated that most of the 14 BCF of additional potential reserves will come from fracture stimulation of the known productive reservoirs.”
The East Flour Bluff gas field is located east of the city of Corpus Christi, under a shallow lagoon known as Laguna Madre. The EFB D-24 well will be drilled from an existing production and drilling peninsula built out into the lagoon.
The well will start vertical and from 305 metres will be directionally drilled out under the lagoon, reaching a maximum angle of 32 degrees until 2,804 metres TVD (total vertical depth), where it will be brought back to vertical to drill through the target reservoirs. The reservoirs are drilled vertically so that subsequent fracture stimulation has maximum effect. The total depth of the well is expected to be 3,414 metres TVD (3,688 metres measured depth).
Expected depth to the top of the first target reservoir is about 3,210 metres measured depth and is anticipated to be reached in 34 days from spud. The well is expected to reach total depth in 44 days.
The field is divided by faulting into the Flour Bluff field to the west of the fault and the East Flour Bluff field to the east. The major reserve potential (227 BCF) is in the Flour Bluff field, with a further 67 BCF in the East Flour Bluff field.
The initial development program consists of three key wells, each designed to test the extent of gas reserves in critical locations in the Flour Bluff field and the East Flour Bluff field. If successful each of the wells would be completed as production wells, Victoria Petroleum said.
The first well BG Webb-1, was located to test for the presence of 227 BCF of gas reserves and additional reserve potential in the Flour Bluff field. The well reached a total depth of 4,117 metres on schedule and after running casing the rig was released on 7 April 2005.
Once the current well has been drilled, the third well in the initial program will be spudded. This will test for the presence of 36 BCF of gas reserves and additional reserve potential in the shallow (1,800 metres) reservoirs in the East Flour Bluff field.
To date the BG Webb-1 well has defined 3P reserves of 104 BCF of gas, to the base of the K15 reservoir in the Flour Bluff field. This comfortably exceeds the consultant’s and operator’s pre-drill estimates of 83 BCF of gas for this section of the well.
To date, 3P recoverable gas reserves for the whole of the Flour Bluff project have increased from a predrilling 90.5 BCF to 127.8 BCF, while the operator’s additional potential reserves of 166 BCF remain to be tested by flow testing the deeper zones in BG Webb-1 and by drilling EFB D-24 and the third well in the program.
The BG Webb-1 well will be placed on production after well completion and testing operations are completed. A pipeline to connect the well to the field gas treatment facility is presently under construction.
Participants' working interests (through local subsidiaries where applicable) are: Sun Resources NL 12.5%, Victoria Petroleum Limited 12.5%, Aurora Oil & Gas 12.5% (formerly Tony Barlow Australia), Texas Crude Energy Inc (operator) 25% and US private interests 37.5%.
