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2012 Two new Oil rich reservoirs are Tonkawa and Marmaton

Will Operators find Hogshooter play in Oklahoma?

  Chesapeake Energy has announced a significant discovery in the Hogshooter play in the Anadarko Basin of the Texas Panhandle and western Oklahoma with the completion of two horizontal wells and said it expects to drill at least 65 more Chesapeake-operated Hogshooter wells in the next few years. The Thurman Horn 406H well was drilled to a vertical depth of approximately 10,000 ft with a lateral section of approximately 4,900 ft. It was drilled more than five miles from established Hogshooter production, in a section of land where three wells had already been drilled to other formations.

During its first eight days of stabilized production, the well averaged daily production of 5,400 bbl of oil, 1,200 bbl of natural gas liquids (NGL) and 4.6 million cu ft of natural gas (mmcf), or approximately 7,350 bbls of oil equivalent/day (boed). Total cumulative production, which includes five days of flowback testing, is 68,400 boe. Current daily production is approximately 7,000 boe.

The Meek 41 9H well, located approximately five miles from Thurman Horn 406H, was drilled to a vertical depth of approximately 10,500 ft with a lateral section of approximately 4,800 ft. During its first 27 days of stabilized production, the well averaged daily production of 1,300 bbl of oil, 365 bbl of NGL and 1.4 mmcf, or approximately 1,900 boed. Total cumulative production, which includes five days of flowback testing, is 53,500 boe. Current daily production is approximately 1,400 boe.

In addition, Chesapeake has drilled two Hogshooter wells that are waiting on completion, the Zybach 6010H and the Hamilton 39 10H. The company estimates its acreage position contains at least 65 more Chesapeake-operated Hogshooter locations to drill during the next few years. The drilling and completion of these wells will be a part of the company’s already budgeted Anadarko Basin drilling program.

Chesapeake CEO Aubrey McClendon said, “We expect this new Hogshooter discovery to provide a significant boost to Chesapeake’s focus on harvesting its existing assets for growth and value creation rather than on pursuing new leasehold. In addition, this new Hogshooter development area should further enhance our growing liquids production, which we expect will have transformational effects on our company’s operational and financial performance in the years ahead. Further, based on production results to date and our research of industry production records, we believe the Thurman Horn 406H well is one of the best oil wells drilled onshore in the Lower 48 in the past several decades. This discovery exemplifies the scale and quality of our world-class asset base and the skill and creativity of our technical teams.”

  Granite Wash

    Horizontal wells in Tight Reservoirs:

 

  Granite Wash is a Lithology Formation Name, but there are so many different  Geological System at different deposition times, such as Permian Granite Wash, Des Moine GW, Hogshooter Wash and others. 

  The Granite Wash production completed with the good rates of return, and more attactive in economic investment - specially when complete a well with high rate of liquids.  The expected drilling and completion costs range from $5.5 to 6.5 Million (Oilshalegas.com).  However Granite Wash is a sucessively deeper pays add to EURs at low incremental Capital Costs.

 

Granite WashThe Granite Wash has been an active play for decades – but lately, it’s become REAL active. Photos courtesy of LINN Energy/Ken Childress Photography

    According to David Brown,  Explorer Correspondent: If you liked what horizontal drilling and fracture stimulation did for shale gas plays, you’ll love what they are doing for tight gas.

Case in point: the Granite Wash. 

 

This decades-old tight-sands play about 160 miles long and 30 miles wide covers parts of    Oklahoma and Texas Panhandle - and horizontal drilling has produces some exceptional rewards from Cleveland formation.  Last July, LINN Energy LLC reported the results of its second operated horizontal well in the Stiles Ranch area of Wheeler County, Texas. The well tested at a 24-hour production of 27 million cubic feet of natural gas and 3,190 barrels of condensate, and yielded 3,530 barrels of natural gas liquids after processing.  It was the highest initial producing rate from Granite Wash during tese times. 

  Then in November, Apache Corp. reported that its first two horizontal wells drilled in the Hogshooter section of the Granite Wash in Beckham County, Oklahoma, each produced more than 2,000 barrels of oil and three million cubic feet of gas per day. Both were drilled to a total vertical depth of about 11,000 feet.

    Chesapeake Energy Corp. of Oklahoma City said its average gas production rate from Granite Wash wells in the Texas Panhandle had jumped from 1.77 million cubic feet a day in 2007 to almost 7.79 million cubic feet a day in 2010.

    “We think the Granite Wash has significant potential,” Walker (Linn Energy) said. “It’s a 3,000-foot-thick zone, so there are numerous horizons to target.”

  The company has seen rates of return in the play of 50 percent to over 100 percent.   LINN Energy has access to about 73,000 net Granite Wash acres – most held by production – across Texas and Oklahoma.

 

Granite Wash 2An active area: LINN Energy plans to spend almost half its 2011 drilling budget in the Granite Wash.

 

Operators emphasize the Granite Wash play is completely different from shale gas. But there are eerie similarities between the technologies used to drill, stimulate and complete both types of play.

An obvious similarity is the play’s low-permeability nature.

“This is a tight sand, and although its permeability and porosity are low, the reservoir quality and porosity are better than those found in most shale plays.  

    Early in the development of the Granite Wash, the industry was drilling laterals of around 2,000 feet. Advances in horizontal drilling technology have substantially increased the lateral lengths to 4,500 foot lateral hole.

 

   Granite Wash operators also tend to favor the high-volume, slickwater fracs common to many shale plays, and operator is using 10-stage to 14-stage frac jobs per well.  

Despite the long history of the Granite Wash (over 2,600 wells producing), its horizontal development is still in the early stages of data-gathering and analysis.

  Alongs with new technologies developing - Operators and Service companies together are working on identify the Sweet Spots of formations by compare different type of Logs; 3 D Seicmic and Core analysis to identify primary production zones and secondary producable zones in 3D plan.

  After identifying of Sweet Spots, the engineers will work on 'Planing a Well'  to identify well location, KOP, directional of lateral hole and the length of the hole.  Three type of completions will be considered to get EUR of a well, Fracture treatments and completion are also importand for getting EUR.  Advanced capabilities in horizontal drilling, effective stimulation and the presence of liquids all have boosted the allure of the Granite Wash.  The economics attractive is the advancement in horizontal drilling techniques; the Granite Wash play is to “assemble a multi-disciplinary team to gain a good understanding of the petrophysics, the geology and the reservoir, and a talented execution team to drill, complete, Well head facilities and produce these challenging wells.”

 

Granite Wash 3

AAPG member G. Randy Keller is director of the Oklahoma Geological Survey at the University of Oklahoma in Norman. He called “Granite Wash” a catch-all term for many types of formations and a wild mix of geology.

“The interesting thing about the Granite Wash is that it’s very hard to define,” he said. “Geologically, I think of it as a garbage pail term for a lot of tight formations out there. The structures are big and the geologic histories therefore complex.

“If we think we know all about the geologic history of these areas, we’re delusional,” Keller added.

In the classic interpretation, he noted, the Granite Wash came from wash or detritus off the Wichita-Amarillo Uplift, producing grains that settled into the tight formations characteristic of the play.

“As you approach these big uplifts, things get a lot more conglomeratic. They don’t call it the Granite ‘Wash’ for nothing,” Keller said.

Smith said the Wash includes “high-energy areas where you have these overlapping (alluvial) fans that come down,” from a mountain-front erosional process.

Local geology can produce just about any type of surprise imaginable.

 

“Some of the things we’ve drilled have essentially been boulder beds,” said AAPG member John Mitchell, Anadarko Basin asset team manager in Tulsa for SM Energy Co., formerly known as St. Mary Land & Exploration.

“The Upper Morrow chert sandstones in Wheeler and Hemphill counties in Texas and Roger Mills and Beckham counties in Oklahoma are the oldest and most prolific Wash reservoirs, although they are not always recognized as Wash deposits,” Mitchell said.

At the same time, the Atokan age Granite Wash in Beckham County contains a substantial amount of dolomite, he added.

Across the entire play area the Wash “changes vertically and horizontally – it’s very complex. It is 50 or 70 different sandstone or conglomerate sections, developed locally,” Mitchell explained.

“It’s fascinating,” he added, “but it’s a challenge.”

 

Granite Wash 4

In addition to providing a source for the oil and gas, the interbedded marine shales have turned out to be a blessing for mapping the Granite Wash, according to Mitchell.

“The patterns of complexity are broken up by these high-stand shales that provide excellent markers,” he said.

But the play is distinctly different from shale gas plays, Mitchell observed.

“We have more storage than shales, I think,” he said. “It is a sandstone, a conglomerate. We do have more porosity.”

While the need for water supply for high-volume fracs is similar to shale plays, operators in the Granite Wash can see more injected water coming back from a formation, he said.

“The shales tend to absorb a lot of water because they’re so desiccated. In the Granite Wash you tend to get a lot of load water back,” Mitchell said.

“I think water management is increasingly going to be an issue,” he added.

Today, the Granite Wash is already generating buzz as one of the most attractive play areas around, with favorable economics thanks largely to the presence of condensate, natural gas liquids and even oil.

Operators benefit from a chance for strong production, good access, a long history in states that favor hydrocarbon development and growing infrastructure.

Also, the application of advanced techniques developed for shale-gas production doesn’t hurt.

“If we’re successful,” Mitchell said, “we’ll be drilling wells out here for the next few decades.”End of Story

 

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   The Granite Wash is a tight-sand reservoir located between Texas Panhandle and Western Oklahoma.  The granite Wash was deposited in a series of Alluvial fans and fan delta interlayer betwwen sand and shale at the depth from 9000' to 12,500 ft (Dutton, 1982): The thickness from 1500' to 3,500 ft with different permeability (Smith et al., 2001).  Completion has changed from vertical wells to different horizontal well completions, with economically compatible to wells in the big shale plays.  The production study showed that after 12 Months of production from OHMS wells outperformed the cemented liner, plug and perf wells by 33%. 

 

 

Ref -http://oilshalegas.com/granitewash.html

       http://www.aapg.org/explorer/2011/02feb/granite_wash0211.cfm

       OCC - at http://www.green2010.us/apps/documents/

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