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Madisonville Project, Madison County, Texas

  • Located 100 miles north of Houston.
  • Company presently owns 20% Net Profits Interest in the Rodessa formation at 12,000’ and the deeper zones; The Company also owns a 20% Net Profits Interest in the gas treatment plant.
  • Impurities in the gas stream – approximately 28% of raw gas.
  • Initial gas treatment plant for 18 mmcf/d designed capacity completed in May, 2003 at a cost of $30 million.
  • Production commenced in May, 2003.
  • Gas treatment plant acquired by GeoPetro in December 2008.
  • The Rodessa formation is expected to produce 18 million cubic feet per day of natural gas.
  • 18,000 foot deep exploratory well is planned in the future to test six prospective formations below the Rodessa. “Bail out” zone in the Rodessa.
  • Deep discoveries by EnCana with wells testing up to 90 mmcf/d stirred significant industry interest.
  • The March 23, 2021 transaction with Promise Energy Madisonville, LLC resulted in GeoPetro and its subsidiaries retaining a fully carried 20% Net Profits Interest in the entire Madisonville Project.

THE RODESSA FORMATION

  • Structural closure at Rodessa Level.
  • 270 feet of structural relief at Rodessa.
  • 66 feet of average net pay.
  • Ruby Magness well has produced in excess of 20 BCF to date.
  • Entire structure covered by encouraging 3-D seismic.

PLANNED DEEP WELL

  • Six potential zones untested below the Rodessa.
  • 400 feet of estimated structural relief at Smackover level.
  • All six zones beneath the Rodessa are productive in nearby vicinity.
  • Deep well planned in the future.

GeoPetro Resources Company and its subsidiaries (“GeoPetro”) own a 20% Net Profits Interest in the Madisonville Deep Project (the “Project”) located in Madison County, Texas. The Madisonville Deep Project represents a rare opportunity to explore and develop multiple stacked pays on a known producing anticline with a resource upside potential approaching 1 trillion cubic feet of gas.
The Madisonville Deep Project underlies the Madisonville Field, located 100 miles north of Houston. The Madisonville Field has been a prolific producer of oil and gas from five different horizons for over 50 years. The field was discovered by “Silver Dollar” Jim West in 1945 with the Boring No. 1 well, which was drilled to the Rodessa formation at approximately 12,000’. The well blew out at a reported rate of 80+ million cubic feet of gas per day for three days during a cased hole DST. However, due to hydrogen sulfide in the Rodessa gas, these reserves were never developed until 2003. A shallower, sweet gas/oil completion opened the Madisonville Field, which now has had over 125 wells. Cumulative production exceeds 30 million barrels of oil and 70 billion cubic feet of natural gas out of the shallower zones above the Rodessa. In 2003, GeoPetro commenced production from the Rodessa formation which has now exceeded 30 billion cubic feet of gas.
Substantial upside potential in the Project exists in the opportunity to explore and develop deeper rights in the Madisonville field. Additional reserves equal to or greater in magnitude to the current Rodessa zone may exist in following deeper zones:

  • Pettet/Sligo – Cretaceous – 14,000’
  • Travis Peak – Cretaceous – 14,500’
  • Cotton Valley Sand – Upper Jurassic – 15,000’
  • Bossier – (Turbidite) Upper Jurassic – 16,000’
  • Cotton Valley Lime – (Pinnacle reefs) – Upper Jurassic – 17,000’
  • Smackover – Carbonate – Jurassic – 18,000’

With the Madisonville Deep there is a well defined trap in the form of a four way closed structural anticline shot out with 3-D seismic. Above the Rodessa Zone (12,000’) there are 5 zones at shallower depths that have produced a cumulative 70 billion cubic feet of gas and 30 million barrels of oil within the structural closure.  Within the Rodessa closure, it is estimated that there are over 80 billion cubic feet of gas reserves. This structure has never been drilled deeper than the Rodessa due to the sour gas content encountered in the Rodessa formation, the previous lack of any sour gas processing capability in the vicinity of the field, and the well founded assumption that any reservoirs deeper than the Rodessa on this structure would contain sour gas similar to that encountered in the Rodessa. That all changed when a treating plant with a design capacity of 18-20 million cubic feet of gas per day was placed into service in 2003 to process the Rodessa production. GeoPetro owns a 20% Net Profits Interest in the gas treatment plant. The proposed location for the initial deep test well at Madisonville is expected to be within 1,000’ of the inlet flange of the treatment plant.

The Madisonville Field, located 100 miles north of Houston, has been a prolific producer of oil and gas from five different horizons for over 50 years. The field was discovered by “Silver Dollar” Jim West in 1945 with the Boring No. 1 well, which was drilled to the Rodessa at approximately 12,000’. The well blew out at a reported rate of 80+ million cubic feet of gas per day for three days during a cased hole DST. However, due to hydrogen sulfide in the Rodessa gas, these reserves were never developed prior to GeoPetro’s involvement. A shallower, sweet gas/oil completion opened the Madisonville Field, which now had over 125 wells. Cumulative production exceeds 30 million barrels of oil and 70 billion cubic feet out of the shallower zones above the Rodessa. In 2003, GeoPetro commenced production from the Rodessa formation which has now exceeded 30 billion cubic feet of cumulative gas production.
The Madisonville Field is a NNW-SSE trending anticline at the Rodessa limestone at about 11,800 feet of depth. A 3-D seismic program shot in early 1998 confirmed the size of the structure and slightly increased its size over earlier interpretations.
In 1994, nearly 50 years after the initial discovery, UMC drilled the UMC Ruby Magness No. 1 well as the first follow-up to the Boring No. 1 to test the Rodessa formation. UMC tested the Magness well through 34’ of perforations in the lower Rodessa for about one week in November 1994. The test data show the flowing wellhead pressures to be increasing with the 3 million cubic feet of gas per day rate (on a 11/64″ choke) from 4639 psi to 4652 psi and the 12 million cubic feet of gas per day rate (on a 22/64″) increasing from 3915 psi to 3919 psi. Furthermore, these tests were not even from the vuggy mid-Rodessa, but were from the lower most 13 feet of indicated pay on the logs. From 1994 to 1997, UMC considered various producing plans for the Madisonville Rodessa Field. With the gas prices available during that time, UMC concluded that the field was marginally economic due to the high cost of sulphur recovery plants, the high nitrogen content and the lack of industry sour gas operations in the area.
GeoPetro acquired working interests in the Rodessa formation of the Madisonville Field in 2000. In 2001, GeoPetro re-entered and recompleted the Magness Well. A total of 139 feet of interval was perforated in the Rodessa Formation at approximately 12,000 feet of depth for this well. The well was production tested over a 12-day period in 2001 on various choke sizes with flowing rates ranging up to approximately 20.8 million cubic feet of gas per day with a calculated absolute open flow of 177 million cubic feet of gas per day. The Magness Well commenced production in May of 2003.
The first development well, the Fannin Well, was drilled and completed in 2004. A total of 146 feet of indicated pay was perforated in the well and a flow test of the well was completed in December 2004 from the Rodessa Formation at rates of up to 25.7 million cubic feet of gas per day. GeoPetro commenced production from the Fannin Well in early 2006.
GeoPetro’s 20% Net Profits Interest covers the Rodessa Formation at approximately 12,000 feet of depth. Production began in May 2003 from the Rodessa formation and stabilized at a rate of 18 million cubic feet of gas per day of raw gas. Cumulative production from the Rodessa formation exceeds 30 billion cubic feet since 2003.
In 2006, GeoPetro drilled the Wilson and Mitchell wells. GeoPetro owns a 20% Net Profits Interest in the Wilson and Mitchell wells as well.

The Madisonville (Rodessa) Field is on an old north-south trending anticline in southern Madison County. The sour gas is believed to be sourced up a fault east of the closure from the Smackover/Cotton Valley/Bossier formations. In the middle part of the Rodessa limestone interval, solution waters have created a vuggy/cavernous zone of very high permeability and porosity which was exposed on the crest of the structure. An Epilog Formation Micro scanner log run by UMC in the Ruby Magness No. 1 well shows this zone. The delineation of a fracture pattern by the 3-D seismic and the high permeability demonstrated by the Boring No. 1 well blow-out in 1945 provide evidence of the significant areal extent of the high permeability vuggy zone beyond the Ruby Magness.
In 1994, UMC perforated the lowest of three Rodessa zones in the Ruby Magness No. 1. This interval had about 13 feet of porosity with numerous fractures, but did not contain the vugs of the Middle Rodessa. This test yielded a flow rate of 12 million cubic feet of gas per day at 3915 psi and an AOF of 103 million cubic feet of gas per day. Subsequently in 2001, GeoPetro perforated a total of 139 feet of interval and production tested the well over a 12 day period on various choke sizes with flowing rates ranging up to approximately 20.8 million cubic feet per day of natural gas with a wellhead flowing pressure of 2,910 PSIG with a calculated absolute open flow of the well varying between 160 and 176.5 million cubic feet of natural gas per day.
The Rodessa zone is sealed by anhydrite and shales between 11,700′ and 10,500′. A series of productive formations including Glen Rose, Georgetown, Dexter and Sub-Clarksville have all produced sweet (H2S free) gas and oil in the Madisonville Field since the 1940’s. These upper formations are generally combination structural and stratigraphic traps due to the reduced closure at shallower depths. The 1998 3-D seismic and subsequent drilling confirmed 200+/- feet of simple domal closure over the Rodessa limestone anticline. Jurassic salt beds core the structure and give rise to a north-south normal fault which probably sourced the sour gas up into the normally-sweet Rodessa.
The good Rodessa porosity and virtually unlimited permeability were likely caused by dissolution and karsting during exposure of the structural crest coincident with paleo growth. This is confirmed by the thinning of the Rodessa channels or vugs and fractures as seen on the Epilog between 11,841 feet and 11,863 feet in the middle of the Rodessa interval. These solution channels represent effectively a series of “horizontal” well bores which we expect to encounter across the entire structural crest. It is also possible that the acid-forming gases percolated through the limestone to the spill point and helped form the vugs and solution channels. Like the karsting, these too would be along the crest of the structure.
In summary, the Rodessa porosity on a 3-D mapped anticline is expected to be (a) full, (b) uninterrupted by faults or barriers, (c) connected by a network of solution channels and fractures, and (d) likely to be efficiently drained by a very few high rate wells.

The Madisonville structure has never been drilled deeper than the Rodessa due to the sour gas content encountered in the Rodessa formation, the previous lack of any sour gas processing capability in the vicinity of the field, and the well founded assumption that any reservoirs deeper than the Rodessa on this structure would contain sour gas similar to that encountered in the Rodessa.  A series of productive formations including Glen Rose, Georgetown, Dexter and Sub-Clarksville have all produced sweet (H2S free) gas and oil in the Madisonville Field since the 1940’s. These upper formations are generally combination structural and stratigraphic traps due to the reduced closure at shallower depths. The 1998 3-D seismic and subsequent drilling confirmed 200+/- feet of simple domal closure at the Rodessa level. The deeper intervals below the Rodessa are characterized by increasing vertical closure with increased depth as compared to the Rodessa. Vertical closure at the Smackover level is estimated to be 400+/- feet based on 3-D seismic.
Significantly, Jurassic salt beds core the structure and give rise to a north-south normal fault which probably sourced the sour gas up into the normally-sweet Rodessa. The Smackover is believed to be the source for the sour gas. This north-south normal fault will intersect all of the objective zones in the planned Madisonville Deep test well. Thus all of the zones below the Rodessa will likely be sourced with sour gas having a similar gas composition to that encountered in the Rodessa.
Expected depths of our target formations are as follows:

Expected Formation Tops

5050′

Midway

6350′

Navarro

6680′

Taylor

7420′

Pecan Gap

7760′

Gober

8000′

Austin

8340′

Eagleford (BAC)

8820′

Woodbine

9150′

Buda

9220′

Georgetown

9620′

Fredericksburg

10070′

Paluxy

10280′

Glen Rose

10900′

Anhydrite (1st stringer)

11120′

Massive Anhydrite

11460′

Rodessa

11700′

Rodessa Porosity Bailout objective

12380′

Bexar

12510′

James

12690′

Pine Island

12760′

Pettit/Sligo Primary objective

13250′

Travis Peak Primary objective

15000′

Cotton Valley Primary objective

16500′

Bossier Primary objective

17000′

Cotton Valley Lime Primary objective

18000′

Smackover Primary objective
*Expected Depths based on offset well logs (UMC – Magness #1)

Each of the six objectives, including the Sligo, Travis Peak, Cotton Valley Lime, Bossier and Cotton Valley Sand and the Smackover formation, were deposited on an existing structural high, raising the probability that one or more of these formations will exhibit good to excellent reservoir quality in the form of matrix and/or fractured porosity. Structural “vertical” closure on the formations is expected to range between 200 to 400 feet, raising the probability that each of the objectives will be encountered in a trapping position.
In 2000, GeoPetro acquired licenses for 12.5 square miles of 3D data overlying the Madisonville structure which was shot by Global Geophysical in 1998.