geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

Serravallian The Serravallian is, in the geologic timescale, an List of time periods, age or a stage (stratigraphy), stage in the middle Miocene epoch (geology), Epoch/series (stratigraphy), Series, which spans the time between 13.82 annum, Ma and 11.63 Ma (m ...

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Clarendonian The Clarendonian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 13,600,000 to 9,000,000 years BP, a period of . It is us ...

Hemphillian The Hemphillian North American Stage on the geologic timescale is a North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 10,300,000 to 4,900,000 years BP. It is usually considered t ...

Blancan The Blancan North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 4,750,000 to 1,806,000 years BP, a period of .NALMA classification) of the

Neogene The Neogene ( ,) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period million years ago. It is the second period of th ...

period Period may refer to: Common uses * Period (punctuation) * Era, a length or span of time *Menstruation, commonly referred to as a "period" Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (o ...

,Goliad Formation
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Fossilworks Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was cr ...

.org including the

gomphothere Gomphotheres are an extinct group of proboscideans related to modern elephants. First appearing in Africa during the Oligocene, they dispersed into Eurasia and North America during the Miocene and arrived in South America during the Pleistocene a ...

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Blancotherium ''Blancotherium'' (meaning "Blanco Creek beast") is an extinct genus of gomphotheriid proboscidean from Texas.May, SR; 2019 "The Lapara Creek Fauna: Early Clarendonian of south Texas, USA". Palaeontologia Electronica ...

'' among many other fossil mammals, reptiles, birds and fish. The formation hosts

uranium Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...

deposits and forms the Evangeline aquifer underneath the city of

Houston Houston ( ) is the List of cities in Texas by population, most populous city in the U.S. state of Texas and in the Southern United States. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, it is the county seat, seat of ...

.

Description

The Goliad Formation was described by Plummer in 1933,Baskin & Hulbert, 2008, p.94 as consisting of three members; the ''Lapara Sand'', overlain by the ''Lagarto Creek Beds'', in turn overlain by the ''Labahia Beds'' with outcrop thicknesses ranging from . The Goliad Formation comprises

claystone Mudrocks are a class of fine-grained siliciclastic sedimentary rocks. The varying types of mudrocks include siltstone, claystone, mudstone and shale. Most of the particles of which the stone is composed are less than and are too small to ...

, sand,

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

,

marl Marl is an earthy material rich in carbonate minerals, Clay minerals, clays, and silt. When Lithification, hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae. M ...

,

caliche Caliche () is a soil accumulation of soluble calcium carbonate at depth, where it precipitates and binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or se ...

,

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

, and conglomerates and reaches in certain areas a thickness of .Page et al., 2005, p.7 The formation overlies the Fleming Formation and dates from the

Clarendonian The Clarendonian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 13,600,000 to 9,000,000 years BP, a period of . It is us ...

to the earliest

Blancan The Blancan North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 4,750,000 to 1,806,000 years BP, a period of .Catahoula and Gueydan Formations.Nicot et al., 2010, p.38 The Goliad Formation is recognized regionally across the Texas coastal plain as an interval of dominantly

fluvial A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it ru ...

siliciclastic strata that overlies the Miocene Fleming Formation and underlies Pleistocene terrace deposits. The formation is now interpreted as a basinward-thickening progradational wedge of Middle and Late Miocene age. Stratigraphic thicknesses in outcrop range from , but offshore the interval thickens to as much as .May, 2019 Together with the Catahoula, Fleming and

Oakville Formation The Oakville Formation is a geologic formation in Texas. It preserves fossils dating back to the Neogene period. See also * List of fossiliferous stratigraphic units in Texas * Paleontology in Texas Paleontology in Texas refers to paleontol ...

, the Goliad Formation is part of the Gulf Coast aquifer, an extensive artesian aquifer that produces water primarily for irrigation and municipalities.Page et al., 2005, p.4 The Evangeline aquifer is hosted by the Goliad Formation underlying the city of

Houston Houston ( ) is the List of cities in Texas by population, most populous city in the U.S. state of Texas and in the Southern United States. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, it is the county seat, seat of ...

.Campbell et al., 2018, p.14 The formation hosts

uranium Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...

deposits in the South Texas Uranium Province and is mined for

caliche Caliche () is a soil accumulation of soluble calcium carbonate at depth, where it precipitates and binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or se ...

in

Hidalgo County, Texas Hidalgo County (; ) is located in the U.S. state of Texas. As of the 2020 census, its population was 870,781, making it the ninth-most populous county in Texas, and the most populous county outside of the counties in the Texas Triangle. The ...

.

Fossil content

Tertiary mammal fossils from South Texas were first reported by Dumble (1894) as coming from the Lapara division, later the Lapara Beds (Dumble, 1903).Baskin & Hulbert, 2008, p.93 The following fossils have been reported from the formation:

References

Bibliography

;Geology * * * * ;Paleontology * * * * * {{citation , last=Alroy , first=J , year=2002 , title=Synonymies and reidentifications of North American fossil mammals , publisher=. , pages=

Description

Fossil content

See also

References

Bibliography

Further reading