Raton Basin
The Raton Basin is a structural basin located in Southern Colorado and northern New Mexico and covers an area of approximately 4,500 miles (7242 km). The basin has been a source of coal since the 1870s and began to be a source of coalbed methane in the 1980s.[1] There is also evidence to believe that the meteor strike that caused the Cretaceous–Paleogene extinction event was in this basin due to the iridium anomaly in the area. [2] The geologic features as well as the area the basin covers is shown in Figure 1.
History of the basin
The Raton Basin takes its name from the town of Raton, New Mexico. The basin is bounded by the Sangro de Cristo uplift on the west, the Wet Mountains uplift and Apishapa arch on the north, and on the east by the Sierra Grande arch, all shown in Figure 2. [5] During the Paleozoic era the basin and surrounding uplifts were a part of the continental backbone and the oldest known rocks in the basin are sedimentary ranging in the Devonian and Mississippian age. [5] The sources of petroleum for the basin are marine sediments from the Pennsylvanian and Cretaceous period, as well as the traps, being both structural and stratigraphic in nature. [6]
Fossil Fuel Production
Coal
Although coal is no longer actively being mined coal mining was a staple of the Raton Basin from the late 1880s. From the start of mining to the early 2000s around 104 million short tons of coal were extracted from the basin. [7] As the shift to more efficient and cleaner energy began coal has taken a backseat in production in the basin.
Coalbed Methane
Coals in the basin had been known to contain a large amount of methane and in the early 1990s but were not able to be recovered until 1999 due to lack of infrastructure and economics. [9] Coalbed methane is currently being produced from the basin and will likely be the only fossil fuel play going forward. This recovery process is unique and is pictured in Figure 3 .
Oil & Gas
Within the basin, there are reserves of oil and natural gas, but all efforts to extract them conventionally have not been economical. [7] In the future as technology advances, unconventional methods besides coalbed methane may become viable for the basin.
Petroleum Geology
Source Rocks
A source rock is a rock that is capable of generating or that has generated movable quantities of hydrocarbons. Source rocks in the Raton Basin primarily consist of Pierre shale coal/carbonaceous beds. [6]
Traps and Seals
In the basin, there is a variety of traps being both stratigraphic and structural. In the areas of the basin containing Trinidad sandstone, there is typically no conventional seal. In the Dakota sands of the basin, gas is structurally trapped by the Laramide anticline, the interbedded shale in the basin also can act as traps. [6]
Reservoirs and Migration
Conventional reservoirs in the basin consist of sandstone that ranges up to 50 ft thick with porosity ranging from 2 to 18 percent. Generation and migration began no earlier than the Eocene. [6]
Geologic Risks and Uncertainties
From the 1880s to the early 2000s the Raton basin remained a source for coal production in the United States. As it was shown that the coal produces a large amount of methane efforts began to extract this coalbed methane from the early 2000s onward to the present day. The basin has also had the highest amount of earthquakes in Colorado and New Mexico from 2008-2010 representing unusual seismic activity. [1] Correlations have been drawn from this back to the start of saltwater injection in the basin from 2000 onward. This discovery could slow the production of coalbed methane due to environmental/safety reasons in the future if seismic activity continues. However, the Raton Basin's frequency-magnitude and spatiotemporal statistics are not distinguishable from tectonic seismicity which suggests the earthquakes are primarily releasing tectonic stress. [10]
Future Petroleum Potential
The future of petroleum in the Raton Basin will most likely be focused on unconventional plays. Within that, most production will likely be from Coalbed Methane in the near future. Coalbed methane is currently the most attractive petroleum asset within the basin due to the basis of cost to extract as well as reserve volumes. [9]
Petroleum and facility engineering aspects
What's unique about the engineering and facilities in the Raton Basin is that there was no infrastructure to transport gas until 1999. add a ref here. Prior to the start of the 2000's the Raton Basin was almost entirely coal mining operations, as the infrastructure to transport gas began to be implemented, coalbed methane, as well as saltwater injection wells, got introduced. [9]
References
- ↑ 1.0 1.1 Nakai, J. S., et al. “A Possible Causative Mechanism of Raton Basin, New Mexico and Colorado Earthquakes Using Recent Seismicity Patterns and Pore Pressure Modeling.” AGU Journals, John Wiley & Sons, Ltd, 21 Oct. 2017, https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017JB014415.
- ↑ “Osmium-187/Osmium-186 in Manganese Nodules and the ...” Science, 1983, http://science.sciencemag.org/content/222/4624/613?cited-by=yes;222/4624/613.
- ↑ Hoffman, Gretchen. Geologic and Structural Features of the Raton Basin ... 2005, https://researchgate.net/figure/Geologic-and-structural-features-of-the-Raton-Basin-Colorado-and-New-Mexico-Geology_fig1_251311429.
- ↑ Dale, Karly. “New Mexico Oil & Gas Production.” SlideServe, 2 Nov. 2014, https://www.slideserve.com/karly-dale/new-mexico-oil-gas-production.
- ↑ 5.0 5.1 Baltz, Elmer H. “Stratigraphy and History of Raton Basin and Notes on San Luis Basin, Colorado-New Mexico.” AAPG Bulletin, GeoScienceWorld, 1 Nov. 1965, https://pubs.geoscienceworld.org/aapgbull/article-abstract/49/11/2041/35155/stratigraphy-and-history-of-raton-basin-and-notes.
- ↑ 6.0 6.1 6.2 6.3 Keighin, C. Raton Basin–Sierra Grande Uplift Province (041) - USGS. 2005, https://certmapper.cr.usgs.gov/data/noga95/prov41/text/prov41.pdf.
- ↑ 7.0 7.1 Johnson, Ronald, and Thaddeus Dyman. “Potential for a Basin-Centered Gas - USGS.” USGS, 2001, https://pubs.usgs.gov/bul/b2184-b/b2184-b.pdf.
- ↑ USGS. “Coalbed Methane.” Coalbed Methane, 14 Dec. 2021, https://serc.carleton.edu/research_education/nativelands/crow/coalbedmethane.html.
- ↑ 9.0 9.1 9.2 Hoffman, Gretchen, and Brian Brister. “New Mexico's Raton Basin Coalbed Methane Play.” Geoinfo, 2003, https://geoinfo.nmt.edu/publications/periodicals/nmg/25/n4/nmg_v25_n4_p95.pdf.
- ↑ Glasgow, Margaret, et al. “Raton Basin Induced Seismicity Is Hosted by Networks of Short Basement Faults and Mimics Tectonic Earthquake Statistics.” Earth and Space Science Open Archive, 15 Aug. 2021, https://www.essoar.org/doi/10.1002/essoar.10507748.1.