It seems as though geophysical companies never encounter a problem they can’t solve.
A data acquisition program being readied at press time by Global Geophysical Services for Apache Corp. in Tierra del Fuego (TdF) is a prime example.
Apache’s earlier efforts there concentrated on the Argentine side of TdF. That focus began changing once it acquired concessions in a licensing round in neighboring Chile.
In addition to earlier 3-D data, Apache recently acquired new 3-D seismic at TdF in Argentina and wanted to tie this in with new data it planned to acquire in its concessions in Chile.
“We acquired data right up to the border in Argentina,” said Dave Monk, director of geophysics in exploration and production technology at Apache. “We could simply go to the border in Chile, but then there would be a gap in the middle where we didn’t acquire data.”
You see, this is a region where one doesn’t easily move back and forth between countries.
Indeed, the international border running along the middle of Apache’s holdings poses a unique challenge to gathering seamless seismic data. There are international agreements between the two countries that prohibit deploying any kind of equipment crossing the border – and that’s just part of the problem.
“We can’t even send command and control information across the border,” Monk said. “There can be no seismic cables across the border.”
Seismic Without Borders
Undeterred, Apache devised a never-before-used solution that may not have been possible until recently.
The three-month effort was designed to have Global acquiring data in Chile using Sercel’s 428XL wireline telemetry system while simultaneously deploying OYO Geospace’s new land node recording system – Geospace Seismic Recorder (GSR) – on the other side of the border in Argentina.
Global purchased 1,000 GSR channels to use on the project, and Global president and AAPG member Richard Degner noted the project entails the first international deployment of an autonomous land nodal recording system, adding “we think land nodes will redefine the way we do seismic work.”
Monk laid out the plan for the TdF program.
“With the GSR we can put it on the ground and just start recording because it’s a completely autonomous continuous recording system,” he said. “Global will deploy that in Argentina at the same time they’re shooting data in Chile.
“We’ll have no information crossing the border at all,” Monk emphasized. “But if we know what GPS time the shots were taken in Chile, we can extract data at the right time from the continuous record recorded from a long period of time on the GSR system in Argentina – we’ll download the data at the same times we took shots on the other side across the border.
“This has never been done before,” Monk said.
“It’s a way to join the two surveys together,” he said, “so we can form one continuous, contiguous data set.”
Monk noted Apache recently drilled its first TdF well using the most recent 3-D data set acquired in Argentina. Previously, they drilled wells there using older 3-D data.
“We have a lot of leads from the new 3-D data and are hopeful that some opportunities extend across the border to Chile,” Monk said.
Along with other issues, the seismic crews must contend with the environmental challenges that come with the territory.
Monk noted that nearly constant 30-60 mph winds are the norm. There’s a dearth of human inhabitants, but millions of sheep roam the region – and the farmers are highly sensitive about the seismic work disturbing these animals.
“Using the wireless GSR, it’s less intrusive,” Monk said, “and the sheep can’t chew on cables if there are no cables to chew on.”