Editing Refugio County, Texas (section)

==Oil and gas==
Commercial gas was first discovered near the town of Refugio in 1920.<ref name=":0">{{Cite journal |last=A. E. Getzendaner (2) |date=1934 |title=McFaddin-O'Conner, Greta, Fox, Refugio, White Point, and Saxet Fields, Texas |url=http://search.datapages.com/data/doi/10.1306/3D932C26-16B1-11D7-8645000102C1865D |journal=AAPG Bulletin |language=en |volume=18 |doi=10.1306/3D932C26-16B1-11D7-8645000102C1865D |issn=0149-1423}}</ref> Oil was first discovered near Refugio in 1928.<ref name=":0" /> The Refugio oil and gas field had produced 32 million barrels and 271 billion cubic feet of gas by the end of 1937.<ref>{{Cite journal |last=Phil F. Martyn (2) |date=1938 |title=Refugio Oil and Gas Field, Refugio County, Texas |url=http://search.datapages.com/data/doi/10.1306/3D932FDE-16B1-11D7-8645000102C1865D |journal=AAPG Bulletin |language=en |volume=22 |doi=10.1306/3D932FDE-16B1-11D7-8645000102C1865D |issn=0149-1423}}</ref> A major oil field was discovered at Greta in 1933.<ref name=":0" />  The Greta oilfield's estimated cumulative recovery at abandonment are 152.5 million barrels of oil.<ref name=":1">{{Cite report |chapter-url=https://pubs.usgs.gov/publication/ofr99131 |chapter=The contribution of giant fields to United States oil production and reserves |last=Schmoker |first=J. W. |title=Open-File Report |date=1999 |publisher=U.S. Geological Survey |issue=99–131 |doi=10.3133/ofr99131 |language=en|doi-access=free }}</ref> The largest oilfield in Refugio county, the Tom O'Connor oil field, was discovered in 1934.<ref name=":2" /> The Tom O'Connor field's estimated cumulative oil recovery at abandonment is 802.8 million barrels of oil<ref name=":1" /> and over 1 trillion cubic feet of gas.<ref name=":2" /> Other notable oil and gas fields in Refugio county, at least partially, include Anaqua, Bonnie View, Fagan, Huff, La Rosa, Mary Ellen O'Connor, and McFaddin oil and gas fields.<ref>{{Cite web |url=https://gis.rrc.texas.gov/gisviewer/ |access-date=November 15, 2023 |website=gis.rrc.texas.gov}}</ref>

The Quintana Tom O'Connor No. 1-A discovery well's location was based on a gravity survey and a trend of other fields in the southwest and northeast between the Vicksburg Fault Zone and the Frio Fault Zone.<ref name=":2">Mills, H.G., 1970, Geology of Tom O'Connor Field, Refugio County, Texas, in Geology of Giant Petroleum Oil Fields, Halbouty, M.T., editor, Tulsa: American Association of Petroleum Geologists, pp. 292 and 299</ref>  The field is a [[structural trap]] formed by an [[anticline]] on the downthrown side of the Vicksburg Fault Zone.<ref name="Mills, H.G. 1970, p. 292">Mills, H.G., 1970, Geology of Tom O'Connor Field, Refugio County, Texas, in Geology of Giant Petroleum Oil Fields, Halbouty, M.T., editor, Tulsa: American Association of Petroleum Geologists, p. 292</ref>  The faulting is due to "large-scale gravity slumping",<ref name="Mills, H.G. 1970, p. 292" /> and these types of faults are referred to as growth faults, which are [[Fault (geology)#Dip-slip faults|normal faults]] that occur simultaneously with [[Sedimentation#Geology|sedimentation]].<ref name="geology dictionary">{{cite book|last=Bates|first=Robert|title=Dictionary of Geological Terms|year=1984|publisher=Anchor Books|location=New York|isbn=0385181019|pages=571}}</ref>  Most of the oil and half the gas is produced at depths between 4500 and 6000 feet, from 15 oil reservoirs and 4 gas reservoirs in the [[Oligocene]] Frio Formation [[sandstone]]s deposited during [[Marine regression]], notably the "5900-foot sand", the "5800-foot sand", the "5500-foot sand" and the "5200-foot sand".<ref>Mills, H.G., 1970, Geology of Tom O'Connor Field, Refugio County, Texas, in Geology of Giant Petroleum Oil Fields, Halbouty, M.T., editor, Tulsa: American Association of Petroleum Geologists, pp. 292-293 and 295-296</ref>  Gas with some oil is found above these sandstones in the Oligocene Anahuac Formation, deposited in a [[Marine transgression]], notably the "4400-foot Greta sand".<ref>Mills, H.G., 1970, Geology of Tom O'Connor Field, Refugio County, Texas, in Geology of Giant Petroleum Oil Fields, Halbouty, M.T., editor, Tulsa: American Association of Petroleum Geologists, pp. 292 and 294 and 296</ref>  [[Natural-gas condensate|Dry gas]] is found in the [[Miocene]]-[[Pliocene]] Fleming sandstones deposited during marine regression, notably the "L-4 sand, which is overlain by 1400 feet of [[Pleistocene]] Lissie sandstones.<ref>Mills, H.G., 1970, Geology of Tom O'Connor Field, Refugio County, Texas, in Geology of Giant Petroleum Oil Fields, Halbouty, M.T., editor, Tulsa: American Association of Petroleum Geologists, pp. 295-296</ref>

The last major oil field discovered in Refugio county was the Lake Pasture oil field, discovered in 1953, with an estimated cumulative recovery at abandonment of 104 million barrels of oil.<ref name=":1" />