Ask any number of professionals in the oil and gas industry the following question:
“What is the biggest challenge facing on-land seismic acquisition today?”
And you are bound to get the same answer:
“Cows eating the seismic cable.”
Wait.
Don’t leave.
Cattle actually have been known to chew up any unburied or exposed cable left on the ground. It’s a real and serious problem for the seismic acquisition sector.
Okay, a real problem.
Input/Output Inc., a Houston-based seismic company, estimates that up to 50 percent of seismic acquisition time is spent on cable troubleshooting and repair.
AAPG member Charles Wickstrom, managing partner of Spyglass Energy in Tulsa, said his company conducts seismic acquisition operations through Alliance Geophysical.
“We run approximately 500 channels of live lines, of cable on the ground, which means we have 1,500 geophones on the ground at any one time,” Wickstrom said.
“When we’re working in areas where cattle are present, we have a tremendous problem with the cattle eating the cable and the geophones,” he added.
Rodents have been a long-time problem for geophysical companies because they are widespread on land and tend to gnaw into any cable they encounter.
Several kinds of rodent-proofing for seismic cable have been tried through the years.
“Depending on where you shoot in Texas and Louisiana, you have rats that are just unbelievable in how much damage they can cause,” said Joe Broussard, regional manager for Dawson Geophysical Co. in Oklahoma City.
Broussard said his company also has encountered problems from cattle damaging or destroying cable and geophones.
He explained that a number of olfactory irritants, including heavy pine scent and hot red pepper mixtures, have been tried to discourage critters from chomping on the cable.
“There was even somebody who came up with a spray that has lion’s urine in it, but nothing I have ever seen is really effective,” he said.
Deer and even wild pigs can chew through seismic cable put down in forested areas, Wickstrom said.
In the arctic, seismic crews have to protect cable from the arctic fox, which seems to have a special appetite for the lines.
During a seismic project on Canada’s Banks Islands, the crew doused the cable with deisel fuel to discourage gnawing by caribou. Arctic foxes still caused up to five breaks per day.
The prospect of cattle eating through seismic cable brings up a number of technical questions.
For instance, what kind do they like?
Do they prefer the traditional Crunchy Coaxial?
Or is there a move to trendier tastes, like Mocha Fine Filament?
Do cattle see a string of seismic cable and think:
“Buffet!”?
(Don’t) Give Me a Home ...
In the seismic business, the common and correct term for cable that connects the geophone sensors to the seismic recording truck is “cable.”
It’s also called geophone cable or geophone line.
A jughand, jug hustler or juggie is a person on a seismic crew who positions the geophones. (*You will need this information later.)
Wickstrom said Alliance Geophysical can have 20 miles of electrical cable spread over three square miles at one time.
“There might be 15-18 cables destroyed on any given day,” he said. “We have several full-time employees who do nothing but repair cable.”
The longer a cable has to stay on the ground in cattle country, the more likely it is to get chomped.
“With this wide-azimuth 3-D, you can have cable on the ground for 10 days to two weeks,” Broussard noted.
He said seismic cable typically will stay on the ground for an average of seven days during a shoot.
Cattle have been a threat to seismic recorders left in place for a long period to measure earthquake waves, according to an Australian scientist.
“We have to be careful with cattle and sheep,” he said. “Cattle will often destroy a recorder. Sheep you can normally keep at bay by surrounding the recorder with fallen timber.”
(Sheep are easily tricked.)
Range Rovers
The attraction that cable and geophones hold for cattle can be explained in a number of ways.
First, people almost never use the word “smart” and the word “cattle” in the same sentence, except for this one:
“Cattle ain’t too smart.”
Also, cattle will get into anything within chewing reach, including (a personal memory) a box of fencing nails.
“They eat everything,” Wickstrom said. “They’ll eat the wire off the trucks, if you let them get to it.”
Insulation on the cable has been thought to attract gnawing animals.
Wickstrom said “they might be attracted to the sweat on the palms of the jughands.” (*Told you.)
On the theory that salt from sweat attracted the animals, Alliance set out salt blocks in the seismic shoot area, trying to lure the cattle away from the cable, he said.
At other times, farmers have been asked to remove their cattle from the shoot area and pasture them elsewhere.
“We have actually made a plow that makes a trench, and you bury the cable and the geophones at the same time,” Broussard said.
However, land owners aren’t always willing to give permission to bury the cable, he said.
And cattle have proven remarkably persistent at chewing up the lines.
“In our shooting in Osage County (Oklahoma), it became such a problem that we hired cowboys to work on our crew,” Wickstrom said.
These seismic cowboys move the herd away from the cables and pasture them down at night to protect operations, he explained.
Despite the best efforts of the industry, cable loss because of livestock and other animals is a continuing problem.
Finding breaks and repairing or replacing cables can be a time-consuming process, delaying acquisition projects and adding significant expense.
“Some companies have even gone to charging the clients for lost cables,” Wickstrom noted.
Until someone comes up with a better deterrent, seismic cable and geophones will be susceptible to damage by cattle, rats, mice, deer, pigs, foxes and other gnawing creatures.
In response to the growing concern, a survey of well-informed petroleum geologists came up with this question:
What about goats?
“Fortunately, we haven’t gotten any goats yet,” Wickstrom said.
“Thank goodness.”