The BU-D11 / BU-D11ST1 / BU-D11ST2 development well was drilled from the BU-DPP platform by the Ensco 104 jackup rig. BU-DPP is located in the western half of the Bayu- Undan gas condensate field which is in the Production Sharing Contract (PSC) areas of JPDA 03-12 and JPDA 03-13, North Bonaparte Basin, Timor Sea, offshore Northwest Australia. The location is approximately 250km south of East Timor and 480km northwest of Darwin. ConocoPhillips (03-12) Pty Ltd is the operator.
The Ensco 104 jackup drilling rig (previously the Chiles Discovery) was on contract on the Bayu-Undan Field on 1st May, 2002 and following completion of drilling, completion and flow testing operations on the BU-WP1 platform the rig was towed to the BUDPP platform jacket where it was pinned on location on 23rd July, 2003.
BU-D11 well was spudded 17th September 2003 and 36” and 26” hole sections were drilled in batch mode along with the upper sections of other DPP wells.
SAMPLES, SIDEWALL CORES CONVENTIONAL CORES
Drill Cuttings
BU-D11
(Measured depths referenced to RT 58.0 m)
Ditch cuttings spot samples for geological description were caught at 10 or 3 m intervals in
the 16” and 10 5/8” x 12 ¼” hole section between 2972.0 m and 6633.0 mMDRT.
Table 1. BU-D11 Ditch Cuttings Sampling Type and Frequency
Interval mMDRT | Sample Frequency | Sample Type | Distribution |
137.4 to 846.4 846.4 to 2972.0 2972.0 to 2980.0 2980.0 to 6630.0 6660.0 to 6633.0 | None 10 m 8 m 10 m 3 m | No returns Spot Samples Washed & Unwashed Washed & Unwashed Washed & Unwashed | Unwashed: ConocoPhillips 1 set East Timor Gov’t 1 set Washed: ConocoPhillips 1 set East Timor Gov’t 1 set Geoscience Aust. 1 set |
BU-D11ST1
(Measured depths referenced to RT 58.0 m)
Composite washed and unwashed ditch cuttings samples were collected for storage at 10 m
intervals in the 10 ⅝" x 12 ¼" hole section, between 4753.0 and 5730.0 mMDRT. A ditch
cuttings sampling summary is listed in Table 2.
Table 2. BU-D11ST1 Ditch Cuttings Sampling Type and Frequency
Interval mMDRT | Sample Frequency | Sample Type | Distribution |
4753.0 to 4760.0 4760.0 to 5730.0 | 7 m 10 m | Washed & Unwashed Washed & Unwashed | Unwashed: ConocoPhillips 1 set East Timor Gov’t 1 set Washed: ConocoPhillips 1 set East Timor Gov’t 1 set Geoscience Aust. 1 set |
BU-D11ST2
(Measured depths referenced to RT 58.0 m)
Composite washed and unwashed ditch cuttings samples were collected for storage at 5 or
10 m intervals in the 10 ⅝" x 12 ¼", 11” and 8 ½" hole sections, between 2970 and 5476
mMDRT. A ditch cuttings sampling summary is listed in Table 3.
Table 3. BU-D11ST2 Ditch Cuttings Sampling Type and Frequency
Interval mMDRT | Sample Frequency | Sample Type | Distribution |
2970.0 to 2990.0 2990.0 to 5180.0 5180.0 to 5183.0 5183.0 to 5185.0 5185.0 to 5475.0 5475.0 to 5476.0 | 20 m 10 m 3 m 2 m 5 m 1 m | Washed & Unwashed Washed & Unwashed Washed & Unwashed Washed & Unwashed Washed & Unwashed Washed & Unwashed | Unwashed: ConocoPhillips 1 set East Timor Gov’t 1 set Washed: ConocoPhillips 1 set East Timor Gov’t 1 set Geoscience Aust. 1 set |
Hydrocarbon Shows
Gas shows are summarized .
Cores
No conventional cores were cut.
Sidewall Cores
No sidewall cores were acquired.
LOGGING AND SURVEYS
Mud logging
Sperry-sun Drilling Services provided the mud logging services with formation evaluation and pressure monitoring services from surface to total depth. Drilling rate, calcimetries, lithologies, total gas and chromatographic analysis of the ditch gas are plotted on the mudlog.
LWD Logging
BU-D11
(Measured depths referenced to RT 58.0 m)
Sperry-sun Drilling Services ran the open hole LWD logs that are summarized in Table 4.
| Run | Hole Size | Tool String | Interval (mMDRT) | Comments |
| 100 | 36" |  | 137.4 – 141.4 | No MWD tools run |
| 200 | 36" | | 141.4 – 173.9 | No MWD tools run |
| 300 | 26" | DWD | 173.9 – 846.4 | Ran only Directional tool |
| 400 | 16” | DIR/DDS/ DGR | 846.4 – 1770.0 | |
| 500 | 16” | DIR/DDS/ DGR | 1770.0 – 2972.0 | |
| 600 | 12 ¼” | DIR/DDS/ DGR | 2972.0 – 4115.0 | Erratic real time signal due to increased downhole vibrations and noise. |
| 700 | 12 ¼” | DIR/DDS/ DGR | 4115.0 – 6633.0 | |
| 800 | 12 ¼” | DIR/DDS/ DGR | 6633.0 – 6633.0 | Lost in hole at 4975.4 mMDRT. End of run time used as time of twist-off. |
BU-D11ST1
(Measured depths referenced to RT 58.0 m)
Sperry-Sun Drilling Services ran the open hole LWD logs that are summarized in Table 5.
Run | Hole size | Tool String | Interval (mMDRT) | Comments |
900 | 12 ¼” | DIR-DGR-DDS | 4753.0 – 5730.0 | Tool lost in hole at 5730 mMDRT. Tool string severed at 3173.0 mMDRT. Severing time used as the end of run. |
BU-D11ST2
(Measured depths referenced to RT 58.0 m)
Sperry-Sun Drilling Services ran the open hole LWD logs that are summarized in Table 6.
Run | Hole size | Tool String | Interval (mMDRT) | Comments |
1000 | 12¼” | DGR-DIR | 2970.0 – 3077.0 | BU-D11ST2 hole direction indicated that it was tracking the BU-D11ST1 well bore very closely and could not break away from it to kick-off successfully. Had to pull out, change bit (mill tooth), change angle in motor (1.5°) and set another kick-off plug. |
1100 | 12¼” | DGR-DIR | 2970.0 – 3033.0 | Successfully kicked-off ST2. |
1200 | 12¼” | DGR-DIR | 3033.0 – 4021.0 | Data in the Vee and Wangarlu were quite bad due to excess downhole noise and eventual pulser failure. |
1300 | 12 ¼” | DGR-DIR | 4021.0 – 4291.0 | No resistivity SEDP/SEMP data from 6102.0 mMDRT. ACAL and BAT run in memory only mode. |
1400 | 12 ¼” | DGR-DIR | 4291.0 – 5022.0 | |
1500 | 11” | PCD-PCG | 5022.0 – 5183.0 | PCD: Pressure case Directional PCG: Pressure case Gamma |
1600 | 8 ½” | DIR-DGR/ DDS-SLD- EWRP4- CNP-BAT-ACAL | 5183.0 – 5292.0 | ACAL and BAT in recorded mode only. Tool quit pulsing after connection at 5282m. Several attempts were made to restart tool. On surface no communication with the HCIM downhole processor. Recorded data only for BAT and ACAL. Recovered memory data only to 5260 mMDRT. |
1700 | 8 ½” | DIR-DGR/ DDS-SLD- EWRP4- CNP-BAT-ACAL | 5292.0 – 5336.0 | ACAL and BAT in memory mode only. Tool stopped pulsing after connection at 5333 mMDRT. Several attempts were made to restart tool. |
1800 | 8 ½” | DIR-DGR/ DDS-SLD- EWRP4- CNP-BAT-ACAL | 5336.0 – 5476.0 | ACAL and BAT in memory mode only |