By an OGJ correspondent
PORT OF SPAIN, Nov. 7 -- The world's leading oil and gas companies are not ready to give up their search for hydrocarbons in commercial quantities in deep waters off Trinidad and Tobago, even though they have already spent hundreds of millions of dollars.
So far, 6 wells have been drilled, with no commercial discoveries, in four blocks awarded under production-sharing contracts in 1998.
The wells were drilled in water depths of 750-1,500 m under PSCs awarded by Trinidad and Tobago's Ministry of Energy to a consortium of Shell Trinidad Ltd., Agip Trinidad & Tobago Ltd., and Petroleum Co. of Trinidad & Tobago Ltd. (Petrotrin) in Block 25a; ExxonMobil Corp., Blocks 25b and 26; and BP PLC, Petroleo Brasileiro SA (Petrobras), Norsk Hydro AS, and Petrotrin, Block 27.
Shell's Trinidad program
Shell, which is operator with 55% interest in Block 25a, drilled the first deepwater well, Haydn 1, in 1999 but discovered only 300 bcf of natural gas. However, the company has been re-energized by BHP Billiton Ltd.'s major oil discovery of close to 1 billion bbl of OOIP in Oligocene sands on Block 2c, 50 km west of Shell's block. Shell looked at the possibility that the Oligocene sands trend to the east into its block.
Daniel Truempy, the Swiss geologist and general manager of Shell Trinidad, conceded, "We did (reexamine) the block to see whether we would find the Oligocene, but our well correlation does not include the wells from the 2c area." However, having been given a 1-year extension on its first-phase exploration to February 2003, Shell is gearing up to restart its exploratory efforts in Block 25a come December.
The company would be returning to the western part of the block where Haydn 1 was drilled into Pleistocene sands.
Truempy explained, "We are targeting the pre-Pleistocene—what horizons in the pre-Pleistocene, we are actually not sure ourselves. We know from our seismic how far we want to go. It's a seismic reflector we want to see. We are not absolutely sure what age the seismic reflector is at present. What we are after is oil sands and if they are in the Pliocene or in the Miocene, we will be quite happy."
The fact that Shell completely changed its original drilling plan from the eastern part of the block to the west suggests its review of the 3D seismic was fruitful.
Truempy announced that Shell would drill a well it is calling Pepper Sauce.
Shell is obligated to drill two more exploratory wells under terms of its PSC; Truempy said Pepper Sauce would be followed by Roti of Callaloo, "depending very much on the results we obtain."
It is likely to take 25 days to drill Pepper Sauce to 2,000 m below mud line in water depths of 1,050-1,100 m. Pepper Sauce is expected to cost $12 million. Truempy said, "We are testing an idea, and it's pretty exciting. I certainly am quite bullish for oil. I think there is oil potential in the area. Commercial oil potential, of course, is quite a different matter."
BP's drilling program
While Shell has committed itself to drilling another well come December, BP is still trying to determine if it made a commercial discovery on Block 27. It was 5 months ago that the company drilled its first deepwater well, Catfish 1, which turned out to be the most expensive well ever drilled in Trinidad and Tobago, costing BP Trinidad & Tobago LLC $100 million. Peter Rattey, recently appointed president of BPTT's exploration performance unit, said, "It is impossible to say at this stage what we have found. We are still doing seismic reprocessing on the well, and that will not be completed until the fourth quarter of 2002. We can't rule out an oil pool, though we can't say if it's there either."
He added, "We do have sands. We do have a reservoir. We do have proof that we have trapped hydrocarbons. That confirms there is a hydrocarbon system that is working. But it is unclear as to how good it is."
Even samples taken from the well have not helped BPTT's experts to come to any firm conclusions. Rattey said, "There is still academic debate in the company about whether we have liquids source or a gas source."
The PSC for Block 27 obliges BPTT to drill at least two exploratory wells in the first phase of the contract. Whether that will happen remains to be seen. Even though BPTT says it has not determined if it made a commercial find, Rattey has conceded that Block 27 has modest prospects. He said, "It is too early to be saying we are going to drill another well in the block. By the middle of the first quarter of 2003, we will be able to talk more powerfully to that, once we understand what we want to do with Catfish."
Meanwhile, BPTT and 11 other companies are funding a 2D seismic survey in the ultradeep waters off Trinidad and Tobago.
ExxonMobil has already shown it is prepared to give up its blocks on which the PSC calls for seven exploration wells to be drilled in the first phase. Earlier this year, it offered the blocks on an Internet website where international oil companies list blocks they wish to unload whole or in part.
Pres. Mark Fincher said ExxonMobil was formulating proposals for future work and had not "given up on the deepwater," although it was looking for a partner. He said, "We were seeking to farm out our interest in the two blocks, but no agreement is imminent."
The company failed to find oil in Blocks 25b and 26 and recently announced that its back-to-back wells were both plugged and abandoned as dry holes.
Despite the lack of concrete success, Energy Minister Eric Williams said he is still confident that oil would be found in the deep water. He said, "The history of Trinidad and Tobago's exploration is full with examples of people making discoveries after years of failure. It is the nature of the business, and of course it is no secret that this country has some of the most challenging geological formations."