
The Woodbine Group is a geological
formation in east
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 ...
whose strata date back to the Early to Middle
Cenomanian
The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...
age of the
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...
.
It is the producing formation of the giant
East Texas Oil Field (also known as the "Black Giant") from which over 5.42 billion barrels of oil have been produced. The Woodbine overlies the Maness Shale,
Buda Limestone, or older rocks, and underlies the
Eagle Ford Group or
Austin Chalk. In outcrop the Woodbine Group has been subdivided into the Lewisville Sandstone, Dexter Sandstone, and/or Pepper Shale formations.
Thin-bedded sands of the Woodbine and Eagle Ford are collectively referred to as the "Eaglebine" oil and gas play in the southwestern portion of the East Texas region.
Dinosaur and crocodilian remains are among the fossils that have been recovered from the formation.
[Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." ''in'' Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. p. 574-588. .] This fossil formation preserves organisms that were endemic to
Appalachia
Appalachia ( ) is a geographic region located in the Appalachian Mountains#Regions, central and southern sections of the Appalachian Mountains in the east of North America. In the north, its boundaries stretch from the western Catskill Mountai ...
.
The Woodbine Group was first mapped and named by
Robert T. Hill, known as the "Father of Texas Geology", for outcrops near the small town of
Woodbine, Texas in 1901.
The Woodbine represents ancient river and delta systems that originated from erosion of the Ouachita Uplift in modern-day
Oklahoma
Oklahoma ( ; Choctaw language, Choctaw: , ) is a landlocked U.S. state, state in the South Central United States, South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northea ...
and
Arkansas
Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...
and the Sabine Uplift in modern-day
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 ...
and
Louisiana
Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...
. Sediments from these deltas flowed into the East Texas and Brazos Basins of the ancient East
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 ...
shelf.
[Denne, R. A., and Breyer, J. A. (2016). Regional depositional episodes of the Cenomanian-Turonian Eagle Ford and Woodbine groups of Texas: ''in'' Breyer, J. A. (ed.), The Eagle Ford Shale: A renaissance in U.S. oil production, AAPG Memoir 110, p. 85-125.]
The Arlington Archosaur Site is a location in
Arlington, Texas that currently excavates fossils from the Woodbine Group. It became available to access by the
University of Texas at Arlington (UTA) in spring of 2008. UTA and the
Dallas Paleontological Society have excavated at the site up to present day, where work continues.
[About Arlington Archosaur Site](_blank)
/ref>
Vertebrate paleofauna
*'' Scolomastax sahlsteini'': A paralligatorid endemic to Appalachia.
*'' Ampelognathus coheni'': A small-bodied ornithopod
*'' Protohadros byrdi'': "Partial skull, teeth, partial postcranium."["Table 19.1," in Weishampel, et al. (2004). Page 417.] A hadrosaur found in Flower Mound, Texas in the early 1990s.
*'' Dallasaurus turneri'': Full skeleton.
*'' Woodbinesuchus byersmauricei'': Lower jaw and a variety of postcranial elements, such as vertebrae, limb bones, shoulder and hip bones, and bony armor.[Lee, Yuong–Nam (1997). The Archosauria from the Woodbine Formation (Cenomanian) in Texas: Journal of Paleontology, v. 71, n.6, p. 1147–1156]
*Unnamed theropod[Fossils at AAS](_blank)
/ref>
*'' Deltasuchus motherali'': Parts of the upper skull, most likely the apex predator in its ecosystem.
*''Terminonaris
''Terminonaris'' is a genus of extinct pholidosaurid crocodyliforms that lived during the Late Cretaceous (Cenomanian and TuronianWu X-C, Russell AP, & Cumbaa SL. 2001. ''Terminonaris'' (Archosauria: Crocodyliformes): new material from Saskatchew ...
robusta'': A pholidosaurid crocodyliform whose remains have been found in North America and Europe.
*'' Flexomornis howei'': A enantiornithe bird.
*'' Pleurochayah appalachius'': A recently described species of bothremydid turtle, which is also known as a side-necked turtle.
* ''Mawsonia'' sp., a giant Coelacanth known from Africa and South America, but fossils of the genus were described in 2021.
*'' Bardackichthys carteri'': an ichthyodectiform fish.
*Indeterminate Nodosauridae.
*Indeterminate Carcharodontosauridae.
*Indeterminate Tyrannosauroidea.
*Indeterminate Ornithomimosauria.
*Indeterminate Dromaeosauridae
Dromaeosauridae () is a family of feathered coelurosaurian theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from ...
.
*Indeterminate Troodontidae.
*Indeterminate Coelurosauria.
Other fossils
Other vertebrate fossils that have been identified in the Woodbine include lungfish, fish
A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
, turtle
Turtles are reptiles of the order (biology), order Testudines, characterized by a special turtle shell, shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Crypt ...
s, shark
Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the ...
s, and coprolite
A coprolite (also known as a coprolith) is fossilized feces. Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour (in this case, diet) rather than morphology. The name ...
s containing bones. Invertebrate fossils found in the Woodbine include ammonite
Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...
s, '' Inoceramus'', oyster
Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but no ...
s, crustacean
Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...
s, and agglutinated foraminifera
Foraminifera ( ; Latin for "hole bearers"; informally called "forams") are unicellular organism, single-celled organisms, members of a phylum or class (biology), class of Rhizarian protists characterized by streaming granular Ectoplasm (cell bio ...
.
*'' Necrocarcinus christinae'': a podotreme crab.
See also
* List of dinosaur-bearing rock formations
This list of dinosaur-bearing rock formations is a list of geologic formations in which dinosaur fossils have been documented.
* List of stratigraphic units with dinosaur body fossils
* List of stratigraphic units with dinosaur trace fossils
** ...
References
{{coord missing, Texas
Cretaceous Arkansas
Cretaceous geology of Texas
Upper Cretaceous Series of North America
Cenomanian Stage
Petroleum in Texas
Sandstone groups of the United States
Siltstone groups
Mudstone groups