Terra performs between 5 - 10 projects per year and the following case studies are examples of the effectiveness of Terra's innovative technology. For more indepth information on Terra, go to Terra Energy & Resource Tech.
TERRA CASE STUDIES
CASE STUDY #1: CHINGIZ-KAZAKHSTAN
Karatobinsky region of Western Kazakhstan
The Chingiz oil field, located in the Karatobinsky region of Western Kazakhstan, was discovered in 1986 via the exploratory well #12 drilled on a seismic identified structure.
The structure is confined to a northeast bound salt layer complicating the western slope of the Chingiz salt dome, located around the second steep bench of salt. According to the seismic materials, essential elements of the structure in the western slope are the so called salt walls, or salt benches, with displacement reaching ten meters. Their analogs in the super saline complex are tectonic faults that are circular in shape and form reservoir traps.
The reservoir is a stratal arched deposit limited along the strike zone by adjoining salt and tectonic faults. Productive formations have been revealed at a depth of 1706 m (abs- 1600 m). The oil to water contact of the reservoir has been established at 1625 m. The established thickness of pay is 25 m and may be in excess of 400 m wide at 1200 m level, if the drilling location is at the crest of the structure. The dimensions of the trap are 6 x 2.5 km.
The host rocks are dominated by fine-grained polymictic sandstones and aleurolites of Lower Triassic, found at 1300 - 1740 m. Based on accurate estimates, the porous type of host rocks has an average porosity of 23% and a permeability of up to 1000 fm2. Compact clay bed rock over 10 m thick serves as the cap. Effective oil-saturated thicknesses in the oil zone may attain 15 m, with the average effective thickness reaching 8 m.
A new field had been identified and was still under exploration. Host rocks included Lower Triassic sandstones at 780 to 820 m. Pay thickness was estimated at 6.6 m. Dimensions of reservoirs: 0.5x0.5 km. The oil to water contact has been traced down to the 682 m level.
CASE STUDY #2: T-FIELD-KAZAKHSTAN
Mangistau Province, Kazakhstan
The T-Field is located in Mangistau Province, Kazakhstan. The field was discovered in 1979 where 23 wells have been drilled to date to the maximum depth of 880 m. All of the wells have been shut in as dry holes or uneconomic. Structurally the field is represented by a northwest-trending brachy-anticlinal fold complicated by a diagonal fold in the south.
Two oil reservoirs have been delineated confined to the roof of Hauterivian formations and to the Lower Albian. The stripped section includes alternating sandstones, clayey aleurolites and clays. Reservoirs in the Hauterivian are stratified, arched and tectonically screened, while those in the Albian are also stratified, arched but tectonically and lithologically screened.
In the Mangyshlak peninsular of the pre-Caspian basin, where The T-Field is located, Cretaceous and Jurassic formations were the only historically proven sources of heavy oil and gas production.
The client had a myriad of geological and geophysical information, including 2D seismic, as well as production data for the past fifty years of exploration and production in the area.
CASE STUDY #3: DEWEYVILLE - E. TEXAS
Newton County, Texas
The Deweyville Prospect was located in Newton County, Texas. The primary objectives for the Deweyville Prospect were the same prolific producing sands from the West Starks (cumulative production in excess of 41 BCF Gas with 5.8 million barrels of oil) the Yegua # 3, # 4 and # 7 Sands. The Yegua #5 sand is an additional objective that produces regionally along trend. The West Starks Field is located just across the Texas border, on the Louisiana side of the Sabine River in Calcasieu Parish.
The proposed drilling depth to test these objectives was 13,000’. One string of protective pipe is necessary in order to drill for these prolific producing, objective sands. Substantial subsurface well data and 2D and 3D seismic data defined the Deweyville Prospect. The prospect is situated in the down-dip section of the Yegua Trend, within the Gulf Coast Salt Dome Basin. Geopressure is present in the shaly Jackson Formation directly above the Yegua Formation. One string of protective pipe needs to be set in order to drill for the Yegua objective sands. Elongate, subtle, fault closures and anticlinal structures downthrown to regional trending northeast — southwest down-to-the-coast faults can trap significant hydrocarbon reserves.
The Deweyville Prospect was positioned along the same fault or fault segment that traps hydrocarbons at many prolific oil and gas fields. West Starks (in excess of 41 .42 BCF Gas, 5,833,504 BBL Oil), Lunita (in excess of 13.371 BCF Gas, 1,007,824 BBL Oil), DeQuincy (in excess of 4.8 BCF Gas, 1,173,127 BBL Oil), East Perkins (in excess of 1.949 BCF Gas, 113,788 BBL Oil), West Buxton Creek (in excess of 1.33 BCF Gas, 1,309,276 BBL Oil), Buxton Creek (in excess of 9.14 BCF Gas, 1,464,057 BBL Oil), and Long Prairie (in excess of 4.7 BCF Gas, 160,000 BBL Oil).