Well Summary
The BU-D06/BU-D06-ST1 development well was drilled from the BU-DPP platform by the Ensco 104 jack up 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 jack up drilling rig (previously the Chiles Discovery) was on contract on the Bayu-Undan Field on 1st May, 2002 and following drilling, completion, perforation and flow testing of BU-WP1 wells the rig was towed to the BU-DPP platform jacket where it was pinned on location on 23rd July, 2003.
Regional Geology: The structure of the Bayu Undan field is a broad east-west trending horst block with multiple reservoirs set up by internal faults. The hydrocarbon-bearing section of the field is found in the upper part of the Early to Mid Jurassic Plover and the Late Jurassic Elang Formation. The Flamingo Group shales and argillaceous siltstones provide the top seal.
SAMPLES, SIDEWALL CORES CONVENTIONAL CORES
Drill Cuttings
BU-D06
(Measured depths referenced to “Medium” RT elevation - 48.6m).
Ditch cutting spot samples for description only were caught at 10 m intervals in the 17 ½" hole section between 837.0 and 2130.0 mMDRT. Samples were not collected between 2130.0 and 3208.0 mMDRT due to lost returns.
Table 1: BU-D06 - Ditch Cuttings Sampling Type and Frequency
Interval mMDRT | Sample Frequency | Sample Type | Distribution |
128.0 to 837.0 | None | No returns | |
837.0 to 2130.0 | 10m | Spot Samples | |
2130.0 to 3208.0 | No Samples – No returns |
(Measured depths referenced to “High” RT elevation 58.0m)
Composite washed and unwashed ditch cuttings samples were collected for storage at 5 or 10 m intervals in the 10 ⅝" x 14”, 12 ¼" and 8 ½" hole sections, between 3092.0 and 6340.0 mMDRT. Ditch cutting sampling is summarised in Table 2.
Table 2: BU-D06 ST1 - Ditch Cuttings Sampling Type and Frequency
Interval mMDRT | Sample Frequency | Sample Type | Distribution |
3092.0 to 6033.0 6033.0 to 6340.0 | 10 m 5 m | Washed & Unwashed Washed & Unwashed | Unwashed: Conoco Phillips 1 set East Timor Govt 1 set Washed: Conoco Phillips 1 set East Timor Govt 1 set Geoscience Aust. 1 set |
Hydrocarbon Shows
Gas shows are summarised.
Cores
No conventional cores were cut.
Sidewall Cores
No sidewall cores were acquired.
LOGGING AND SURVEYS BU-D06
LWD Logging
(Measured depths referenced to “Medium” RT elevation - 48.6m)
Sperry-sun Drilling Services ran the open hole LWD logs that are summarised in Table 3.
Table 3: BU-D06 - Open Hole FEWD Logging Suites and Intervals
Run | Hole Size | Tool String | Interval mMDRT | Comments |
100 | 36” | - | 127.3 – 132.0 | No MWD tools run |
200 | 36" | 132.0 – 164.5 | No MWD tools run | |
300 | 26" | Dir | 164.5 - 837.0 | Directional only. |
400 | 17½” | Dir/DDS/ DGR | 837.0 - 2665.0 | Discrepancy between the two banks of GR data at some intervals in recorded data. DDS memory filled up due to the extended run (131hours). Maximum recorded depth: 2514 mMDRT. |
500 | 17½” | Dir/DDS/ DGR | 2665.0 - 3208.0 | No recorded data due to loss of the MWD tool in the hole. |
600 | 12¼” | Dir/DDS/ DGR/RES | 3154.0 - 3158.0 | Run for deviation control and to accurately locate casing shoe. After drilling out the casing shoe the drill string became stuck with bit at 3157.8 mMDRT. String was backed off leaving MWD tools in hole. |
BU-D06-ST1
(Measured depths referenced to “High” RT elevation - 58.0 m)
Sperry-Sun Drilling Services ran the open hole LWD logs that are summarised in Table 4.
Table 4: BU-D06-ST1 - Open Hole LWD Logging Suites and Intervals
Run | Hole size | Tool string | Interval (mMDRT) | Comments |
700 | 12¼” | Dir | 3083.5 - 3091.8 | Orientate whipstock and mill window in 13 ⅜”casing. |
800 | 12¼” | DGR-Dir- DDS-BAT | 3091.8 - 3200.0 | |
900 | 10 ⅝" | N/A | 3200.0 - 3203.5 | 10 ⅝" drill out assembly. No MWD/LWD |
1000 | 12¼” | GR-Dir | 3203.5 – 5022.0 | Pulser failed at 5022.0 mMDRT. |
1100 | 12¼” | GR-Dir | 5022.0 - 5278.0 | Pulled out of hole due to mud motor failure |
1200 | 12¼” | GR-Dir | 5278.0 - 6033.0 | Pulser failed at 5969.0 mMDRT |
1300 | 8 ½” | DGR-SLDRES- CNPDir- BATACAL | 6033.0 - 6341.0 | No Resistivity SEDP/SEMP data from 6102.0 mMDRT. ACAL and BAT run in memory only mode. |
Wireline Logging
(Measured depths referenced to “High” RT elevation 58.0 m)
Halliburton Logging Services (HLS) provided through drill pipe CCL-GR correlation and drill
string severing services as summarised in Table 5. No open hole logging was performed.
Table 5: BU-D06 - Wireline Logging Suites and Intervals
Suite | Run | Tool String | Interval (mRT) | BHT/Hours Since Circ. | Comments |
1 | 1 | DCST-CCL-GR | 3130 | Unccesfull attempt to back off stuck drill stril at 3130 mMDRT. Perforated but dialed to fully sever string. | |
2 | DCST-CCLGR | 3117 | Successfully severed stuck drill string at 3117.4 mMDRT | ||
3 | CCL-GR | 3099 - 2990 | Run to accurately locate top of fish prior to running whip stock. |