The Kitan-1 exploration well is located in JPDA 06-105 in the northern Bonaparte Basin. It is located approximately 125 km from the southeast coast of Timor-Leste and 550 km from Darwin. The current equity in JPDA 06-105 is Eni JPDA 06-105 Pty Ltd 40%, Inpex Timor Sea Ltd 35% and Talisman Resources (JPDA 06-105) Pty Ltd 25%. The Kitan Prospect is situated 15 km east of the Laminaria oil field and 8 km eastnortheast of the Buffalo oil field. The prospect is defined on the Ikan 3D seismic as an east–west-trending tilted fault block with the main risk being the integrity of the structure-bounding faults. Kitan-1 was designed to test the prospectivity of the Callovian Laminaria Formation and Bathonian Plover Formation.
Kitan-1 was spudded in 310.9 m of water on the 8th January 2008 utilising the semisubmersible
“Songa Venus” MODU. It reached total depth (TD) at 3568 mMDRT on 3rd February 2008. The primary objective Laminaria Formation was intersected at 3356.5 mMDRT, 76.5 m low to prognosis. The variation between the predicted and actual depth is related to the PSDM velocities being too slow over the well location. On entering the reservoir hydrocarbon shows in cuttings was confirmed using real-time LWD data. A conventional core was cut recovering 100% of the 30 m attempted. Significant hydrocarbon fluorescence was described from the core.
The final wireline log program including an MDT pressure and sampling run confirmed a 27 m net oil column between 3356.5 to 3406.0 mMDRT. An average porosity of 11.5% and water saturation of 30% is interpreted. Analysis of MDT pressures indicates a clear oil gradient of 0.915 psi/m (0.643 g/cc). MDT samples obtained within the reservoir recovered good quality 59° API oil. The oil–water contact is interpreted to be 3406.0 mRT (3381.3 mTVDSS). A DST was conducted over the perforated interval 3357.5 – 3390.0 mMDRT once the 244 mm (95/8") casing was run. The well delivered a facility-constrained maximum flow rate of 6,100 BOPD through a 12.7 mm (32/64”) choke during the clean-up phase. Sampled flow rates varying from 4,329 BOPD through a 11.1 mm (28/64”) choke to 2,488 BOPD through a 7.9 mm (20/64”) choke were also returned during main flow periods. A PLT survey performed by wireline, followed by a bottom-hole sampling completed the production testing on Kitan-1. The well was plugged and suspended as an oil well on 3rd March 2008.
Lithology and Formation Tops.
AGES | FORMATION | LITHOLOGY | Depth | THICKNESS (m) | |
mMDRT (m) | mTVDSS (m) | ||||
1 | 2 | 3 | 4 | 5 | 6 |
Recent - Pliocene | Barracouta Fm. / Sea Floor | limestone - inferred | 335.6 | -310.9 | 600.1 |
Miocene | Oliver Formation | limestone - inferred | 935.7* | -911.0* | 847.0 |
Early Miocene | Cartier Formation | limestone/sandstone - inferred | 1782.7* | -1758.0* | 716.3 |
Oligo - Eocene | Prion Formation | limestone/claystone - inferred | |||
Early Eocene | Hibernia (Grebe) Formation | limestone/chert - inferred | 2499.0* | -2474.3* | 121.4 |
Paleocene | Johnson Formation (Top Paleocene) | Calc. Claystone/Marl | 2621.0 | -2595.7 | 157.5 |
Maas - Camp | Turnstone Fm. (Base Tertiary) | Argillaceous Calcilutite | 2778.5 | -2753.2 | 60.0 |
Camp - Sant | Fenelon Formation | Marl | 2838.5 | -2813.2 | 43.0 |
Santonian | Gibson Formation | Calcareous Claystone | 2881.5 | -2856.2 | 33.5 |
Turonian | Woolaston Formation | Calcareous Claystone | 2915.0 | -2889.7 | 33.0 |
Late Albian | Jamieson Formation | Claystone | 2948.0 | -2922.7 | 169.9 |
Aptian | Darwin Formation | Claystone | 3118.0 | -3092.6 | 10.0 |
Barremian | Echuca Shoals Formation | Claystone | 3128.0 | -3102.6 | 38.0 |
Haut -Vallenginian | Flamingo Formation | Claystone | 3166.0 | -3140.6 | 149.9 |
Tith - Oxfordian | Frigate Formation | Claystone | 3316.0 | 3290.5 | 40.5 |
Callovian | Laminaria | Sandstone/Claystone | 3356.5 | -3331.0 | 73.4 |
na | Oil-Water-Contact | Log Interpreted | 3406.0 | -3381.3 | |
Bathonian | Plover Formation | Sandstone | 3440.0 | -3414.4 | > 127.9 |
Total Depth | 3568.0 | -3542.3 |
Sidewall Cores
Both rotary and percussion sidewall cores were taken during the running of Suite 1 wireline logs at the end of drilling the 311 mm (12¼”) hole section. Rotary sidewall coring (MSCT) was performed in Run 5, resulting in 19 cores recovered from 25 attempted. Routine Core Analysis (RCA) was carried out by GeoTech lab. Percussion sidewall cores (CST) were taken in Run 6, resulting in 50 cores bought, 3 lost, 6 empty and 1 rejected, out of 60 attempted.
Convetional Cores
Conventional coring services were supplied by Corpro Systems Ltd, with one core cut in the 311 mm (12¼”) hole section from 3371.0 m to 3401.0 mMDRT in the Laminaria sandstone. A recovery of 30.0 m (100%) was achieved,
Core | Core Depth (m) |
| Corrected Core Depth (mMDRT) | Recovery (%) | Formation |
1 | 3371.0 – 3401.0 |
|
| 100 | Laminaria |
indicates adjustment downward.
Routine Core Analysis (RCA) was carried out by GeoTech lab. Special Core Analysis (SCAL) was carried out by ACS Laboratories on selected core plugs. At the time of writing this report final SCAL results were not completed. Before core data (porosity, permeability) was used in any processing, it was corrected for overburden stress.
Wire line Logging
Schlumberger provided wireline logging for the 311 mm (12¼") hole section. One open-hole logging suites and three cased hole logging suites were run. Six openhole wireline logging runs were completed on the Kitan-1 well. After the 244 mm (9⅝”) production casing was cemented in place, a cement bond log (Suite 2) was ran to check the integrity of the casing/cement job.
Schlumberger’s new Sonic Scanner tool was used for the first time for this type of analysis however, the tools held up at 3442.9 mMDRT. Despite numerous attempts to reach the shoe the log recorded data from this point upwards without further problems.
To set DST/TCP string in place correlation logs (Suite 3) were conducted.The final suite (Suite 4) of logs was conducted after the well had been shut-in for the final build-up phase of the DST. Run 1 comprised the PLT flow survey across the perforation zone, however the initial tool string run had insufficient weight to pass down hole. The survey was re-run successfully after some weight-bars had been included.
Suite | Run |
| Tool String | Interval (m MDRT) |
|
since circ. | |||||
Open-Hole Logging | |||||||||||
Suite 1 | Run 1 | 04-Feb-2008 |
| 3568 – 335.6 | 106.0 |
| |||||
Run 2 | 05-Feb-2008 | GR-MDT 41 pressure points, 3 sample points, 2 x 450cc PVT samples at each point | 3568 - 3256 | 116.0 |
| ||||||
Run 3 | 05-Feb-2008 | HNGS-MSIP-FMI Sonic Scanner run instead of DSI | 3568 - 2500 | 118.9 |
| ||||||
Run 4 | 06-Feb-2008 | GR-VSI4 50 stations, including 20 checkshots, last good station at 1748m |
| 106.0 |
| ||||||
Run 5 | 06-Feb-2008 | GR-MSCT 25 cores cut, recovered 19, empty 6 | 3460 – 3357.5 | 119.4 |
| ||||||
Run 6 | 06-Feb-2008 | GR-CST 60 shots, bought 50, lost 3, empty 6, rejected 1 | 3568 – 2500 | 119.0 |
| ||||||
Cased-Hole Logging | |||||||||||
Suite 2 | Run 1 | 13-Feb-2008 | CBL-VDL Tools held up at 3442.9 mMDRT, Sonic Scanner used for cement evaluation | 3442.9 – 2492 |
| ||||||
Suite 3 | Run 1 | 17-Feb-2008 | GR-CCL Marker sub on DST string not detected | 3568 – 3000 |
| ||||||
Run 2 | 18-Feb-2008 | GR-CCL Marker sub still not detected | 3568 – 3000 |
| |||||||
Suite 4 | Run 1 | 23-Feb-2008 | GR-PLT Run in hole unsuccessful, not enough weight. Add weight and re-run | 3410 – 3337 |
| ||||||
Run 2 | 23-Feb-2008 | GR-PLT Survey 4 stations | 3410 – 3337 |
|