It may not have been a year for elephant discoveries, but in 2004 a number of important wildcats added to the world’s reserve inventory potentials.
Here is a list of some of those significant finds along with the commentary are reported by the HIS Global E & P Reporting Service, whose editors cover E & P activity in more than 200 countries. A more complete listing is available on the EXPLORER Web site at www.aapg.org.
Algeria – First Calgary’s Ledjmet South 1 wildcat weighed in with a 13,515 bod and 30.9 mmcfgd winner in the onshore Berkine Basin. Sontract hit big with its find in the Hassi Messaoud Basin, there testing 4,445 bod with 4.3 mmcfgd, and with the BKP2 in the Oued Mya Basin, at 3,072 bod and 21 mmcfgd.
Angola – Four deepwater discoveries in the Congo Fan included Total’s Canela 1 testing 6,800 barrels of oil a day, and ChevronTexaco’s KX2 flowing at 5,000 bod.
Egypt – Twenty-seven discoveries were reported including Suco’s 3,000 bod find in the Gulf of Suez, Sipetrol’s 3,250 bod wildcat and Shell’s Shieba 18-3 testing at 1,6000 bod with gas – both in the onshore Abu Gharadig Basin.
Gabon offshore – Vaalco’s Avouma 1 on the shelf of the Lower Congo Basin flowed 6,600 bod.
Nigeria – Total’s Preowei 1B in the deepwater Niger Delta area is potentially significant, as Total has already indicated a desire to develop the find even though the first appraisal well has yet to be drilled.
Mauritania – The offshore again has hosted a number of exploratory wells, and Dana’s Pelican 1 is arguably the best. The operator confirmed in-place reserves of 1.03 tcf, with technically recoverable reserves in the range 600 – 800 bcf together with 10-13 mmb of associated liquids. However, as the base of the hydrocarbon-bearing interval was not encountered, these figures could be revised upwards.
Tunisia – ENI tested two discoveries in the Ghadames Basin, one testing 6,200 bod with 14.3 mmcfgd, and the other at 3,600 bod.
Australia – ChevronTexaco’s Wheatstone 1 exploration well in the North Carnarvon Basin is viewed as a multi tcf gas find that is likely to be tied into Gorgon, or may be even the Northwest Shelf. The well encountered 53.34 m of net gas sands in the objective Jurassic Tithonian and Triassic Mungaroo sands, in which a production test flowed 54 mmcfd of gas.
Also worthy of note is that BHP-Billiton made a number of oil discoveries (Eskdale, Harrison and Stickle) that have opened a medium-sized oil province in the offshore Carnarvon Basin.
New Zealand – The Amokura 1 and Pateke 2 discoveries, drilled by NZOP, were found to be on the same field. They represent the first oil discovery in New Zealand in a number of years.
France – At a country level, Les Mimosa 1 GD is considered as outstanding as it is one of several prospects to have been identified – and also that most of the Lege permit, in which it lies, is now open for bidding.
An Acquitaine Basin discovery by ExxonMobil flowed 1,600 bod.
Poland – PGNG’s Zaniemysl 3 in the Fore-Sudetic Monocline flowed 2.5 mmcfgd, and Cierpisz2 in the Outer Carpathian Foredeep tested at 26.9 mmcfgd.
Bangladesh – Bangora 1 operated by Tullow is a potentially huge, significant discovery that encountered a number of gas-bearing intervals between 2,580 – 3,285 meters. Three lower most intervals were tested flowing a combined 120 mmcfgd, with the shallower units to be tested at a later date.
The company has now tested gas at either end of a 400-kilometer long anticlinal trend, and an accelerated appraisal program is planned.
China – Although no reserves have been assigned, Laopunan 1 has been proclaimed by PetroChina as its largest and most significant discovery in 2004, testing at 4,400 bod and 5.6 mmcfgd. It is located in around three meters of water and was drilled on the Nanpu 2 structure in the southern part of the Nanpu Sag, Bohai Gulf Basin.
PetroChina also struck with five discoveries in the Tarim Basin, including the Yugi 4, testing at 944 bod and 1.8 mmcfgd, and the Lungu 39, flowing at 355 bod and 41.3 mmcfgd.
India – For the second year, India’s offshore has been a key exploration area. In 2004 it is the Reliance wells on the Dhirubhai structure in the NEC-OSN-97/2 block that are regarded as most significant as these have shown the shallow water area of the Mahanadi Basin to hold significant amounts of gas. Reliance reported a total of seven discoveries in three offshore basins.
Indonesia – The Jeruk 1, a big oil discovery made by Santos with likely minimum reserves 170 mmboe contained in the Kujung Formation in the offshore East Java Basin, has been successfully appraised. Eni completed Aster-1 as an important new field discovery. Although untested, this well opens the potential for a new deepwater play in the Tarakan Basin and has high-graded an area where the median line is disputed.
Vietnam – The 09-R 23X well is understood to have flowed about 1,100 bod of 35-degree API crude and is claimed by the operator to be first basement oil discovery in the southern part of Block 09 in the offshore Cuu Long offshore basin.
Colombia – Perenco’s Jordon Este 1 flowed 1,877 bod in the Llanos-Barinos Basin.
Cuba – Although considered non-commercial, Repsol YPF’s Yamagua 1 is an important well in that it is the first to be drilled in Cuba’s deep water and also because light oil was found. The structure is subject to further seismic evaluation, and at least two more wells are being considered.
Mexico – Among the 21 discoveries reported by Pemex, seven were offshore, including the Itla 1 in the Gulf Coast Basin, testing at 1,350 bod with gas, and the Kosni 1 in the Tampico-Misantla Basin, flowing 29.4 mmcfgd.
Venezuela – Oil-in-place for the Travi Este structure, successfully drilled by the Travi Este 2X ildcat, was estimated by PDVSA at the time of logging at 670 mmbo and 2.6 tcf of gas from a 220- meter net pay section in the Naricual and San Juan formations; this ranks among the country’s most important wells in 2004.
Also, ChevronTexaco’s Loran 2X in the Plataforma Deltana is believed to have found reserves of 4-6 tcf and is being touted as the catalyst to launch the country’s LNG project.
Libya – Six discoveries were reported including Repsol’s find in the Murzug Basin testing 1,350 bod.
Saudi Arabia – Shaybah 700 is significant, as it established a new non-associated gas/condensate play and work continues to evaluate a deeper gas objective. It has the potential to be a very large find with reserves estimated at 3 tcf of gas and 100 mmb condensate.
Kuwait – Mutriba 12 was reported to have discovered sweet gas and 50 – degree API condensate in the Lower Triassic Sudair Formation; a second test suffered a technical failure. The well was drilled to a total depth of 6,736 meters and is considered the first non-associated gas producer in Kuwait.
KOC also found 4,850 bod in the DibDibah Sub-Basin with the Bahrah 28.
Gulf of Mexico – Although no reserves have been published, the Jack (ChevronTexaco) and St. Malo (Unocal) discoveries are considered significant as they both are located in the newly established Paleogene trend.
This article first appeared in the January 2005 issue of the AAPG Explorer and published here with kind permission of AAPG.