Plays are hot.
Then they’re not.
Often, all it takes to jumpstart them once again is some new technology along with a passel of geoscience smarts – and favorable commodity prices.
The hydrocarbon-rich Permian Basin in West Texas and New Mexico is a sterling example of boom, bust and then boom again.
There’s much ado about horizontal drilling, hydraulic fracturing, and other new techniques triggering the U.S. shale drilling frenzy, improving production in mature fields, and more.
Truth be told, seismic technology often plays a significant role, perhaps deserving a more prominent position in the spotlight.
Certainly, the Permian Basin, with its intense rejuvenation activity, is one of many regions in a position to benefit from advanced seismic technology.
Its basically rugged, inhospitable terrain ranges from flat to sometimes nearly vertical, and it is populated by any number of cable-gnawing creatures, both large and small. It’s not the ideal environment for ordinary seismic data acquisition systems strung together by heavy high-maintenance cables, which are infamous for troubleshooting issues, and other problems.
Here, as in many areas around the world, the data gatherers and their oil company clients are taking steps to transition to the newest land systems technology generally known as nodes.
Whether dubbed cableless, wireless, cable-free or whatever, these systems include FairfieldNodal’s ZLand® system and its transition zone shallow water counterpart Z700, INOVA HAWK® , Sercel UNITE, OYO GSR, among others.
As one would expect from any arena where companies are battling for exploration advantages, the technology competition continues to escalate.
The newest arrival in the autonomous land node systems milieu is Global Geophysical Services’ (GGS) Autoseis® High Definition Recorder (HDR) developed by its wholly owned subsidiary Autoseis Inc.
The HDR has been used successfully since early 2011 in varying environments and far flung geographic locales, including the Amazon and the Arctic. Its first commercial program commenced in July 2011. A marine version is scheduled to make a commercial debut soon.
“The simple, totally scalable Autoseis HDR has no interconnecting cables and no complex radio links to or between the nodes,” said Tom Fleure, VP of geophysical technology at GGS. “And it’s the only system on the market today that records double precision, true 32-bit seismic data.
“We have deployed more than 100,000 HDR-1C units, principally in heavily wooded areas, jungles, swamp environments or mountainous areas,” Fleure said. “These are locales where terrain, weather and other elements of nature typically challenge the large equipment and crews ordinarily needed to acquire high-quality seismic data.
“In our first year using Autoseis HDR units, we increased our average production rate by 2.3 times over our cable systems, with projects repeatedly coming in under budget,” Fleure added.
This powerful node looks deceptively simple with a lightweight plastic case measuring approximately 2.5 by 3.5 by 0.5 inches. Pop open the case, and the see-through inner pack with the brains tells you this is far-out technology.
A couple of rubberized links, attached to the outer case, terminate in small tube-like gizmos. These are the connectors for the battery and for the receiver group, ordinarily a geophone string.
Each receiver station is attached to a station stake, where they remain unattended until recording is complete. Each HDR provides an independent GPS measurement of its location during recording, which can be used to verify its actual placement.
Near and far trace offsets are easily manipulated, given that channels can be added or subtracted without changing anything in the field if the receivers are deployed.
Once the data are collected, the nodes are retrieved and taken to a specially equipped field trailer. There, the data are downloaded and the batteries recharged prior to redeployment.
With 12-hour/day recording, battery life is 40 days vs. 20 days for 24-hour/day recording.
In line with other available nodal, or wireless systems, Autoseis provides:
Without the potential for cumbersome cables strung out here, there and everywhere, permitting tends to become a bit less trying (read: less expensive and less time-consuming).
Plus, landowners tend to be a happier lot, for the most part.
Given that the Permian Basin is such a hot spot and has so much potential for the future, GGS zeroed in on the opportunity to work a multi-client survey using Autoseis. The project’s focus is the Ozona Arch, specifically Reagan, Crockett and Upton counties in the southern reach of the Midland Basin.
Dubbed the University Lands Project, phase 1 of the high resolution RG3D® Reservoir Grade 3-D survey will cover 355 square miles, which harbor a number of different target horizons.
The likely completion date was expected to be late October; kickoff times for phases 2 and 3 will depend on underwriting availability.
The Ozona Arch exhibits a variety of terrain types, with some areas being excessively steep. To avoid having the vibrator source trucks constantly navigating such difficult areas and to eliminate excessive driving time, some fleets are positioned at the high elevations while others are bottom dwellers, so to speak.
The receiver stations for the survey are laid out in lines, although the flexibility of the system allows for any surface geometry configuration. The stations are positioned 55 feet apart.
“We have six fleets in the Permian with two vibrators for each fleet and are using offset separated source fleets and slip sweep vibroseis technology to optimize crew productivity,” said AAPG member Duncan Riley, GGS’ VP-North America. “We have 120 crew members managing 28,000 channels, or nodes.
“In combination, this receiver and source effort results in really phenomenal sampling and imaging of the complex geology,” Riley noted.
“Compared to conventional 3-D surveys, which have a typical trace density of 350- to 450 thousand traces per square mile, the University Lands program boasts a trace density in excess of 4.3 million traces per square mile,” he emphasized.
In step with a general trend in the industry to go nodal, the company is in the process of converting all of its land crews to Autoseis technology. A 3C version to record both P wave and shear wave data is nearly ready to be launched.
As the name Global suggests, president and CEO Richard Degner thinks big.
Degner, an AAPG member, envisions implementing complete, contiguous seismic coverage over the heart of the Permian Basin, i.e. Midland and Delaware basins and Central Basin Platform, versus the “postage stamp” approach of numerous yet discontinuous seismic surveys, which are the norm here and other places.
“I think,” Degner said, undaunted by the prospect of such a challenge, “it could be done in maybe five years or so.”
The prolific and venerable Permian Basin is made up of an assortment of geological subdivisions. The U.S. Geological Survey breaks it down as Midland, Delaware, Pecos and Val Verde basins along with the Central Basin Platform, Ozona Arch and northwestern, northern and eastern shelves.
Overall, the Permian envelops an area about 260 miles wide and 300 miles long. This region is underlain in large part by thick deposits of mineral-rich sediment, creating one of the most productive oil regions in the world.
The USGS “Assessment of Undiscovered Oil and Gas Resources of the Permian Basin Province of West Texas and Southeast New Mexico 2007” report estimated a mean of 41 Tcf of undiscovered natural gas and a mean of 1.3 Bbls of undiscovered oil in the province. Undiscovered natural gas liquids tallied a mean of 1.0 Bbls.
The first commercial well discovery occurred at the Westbrook Field in Mitchell County in 1921. Soon thereafter, folks were scurrying to acquire leaseholds and drill in the basin.
The ensuing production peaked at two million b/d in the early 1970s.
Then, as oil prices spiraled downward, the major companies headed elsewhere to latch on to bigger opportunities. Operators with lesser economic demands hung on for the most part, and the rig count tallied a paltry 43 wells in 1999, indicating a death knell of sorts for a once-proud giant.
Fast-forward to today, and you’ll see a region bustling with activity. Reported cumulative production of more than 30.4 billion barrels clearly is headed straight up. Given that 2011 production reached 280 Bbo according to the Texas Railroad Commission.
A number of factors are responsible for this revitalization. Think natural gas prices low enough to make you cry and, no surprise, new technology.
This includes horizontal drilling and multi-stage hydraulic fracturing in both horizontal and vertical wells, which remain the technique-of-choice in certain locales.
Additionally, there are the old yet improved standbys, such as waterflooding and CO2 injection, which have long been successfully applied in the basin’s numerous reservoirs.
Perhaps the most intriguing happening is increased production via deeper drilling, which, in turn, has triggered some funky nomenclature.
Given the current glut of natural gas produced in the United States, principally from the raft of shale gas fields, the oil-rich Permian is darned near irresistible.
Even the majors are setting up camp once again.
The most recent news is from Shell Oil and Chevron, which recently snapped up 618,000 and 246,000 acres, respectively, from Chesapeake Energy in the Delaware Basin – which itself holds a number of stacked oil and wet gas plays.
Chevron’s purchase added to its existing 700,000-acre position in the basin.