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27-662: The Chachao Formation is a geological formation in the Mendoza Province in northern Patagonian Argentina . It is Valanginian in age and is predominantly marine, being deposited at a time of marine transgression in the Neuquén Basin , and predominantly consists of carbonate rocks. The formation belongs to the Mendoza Group , sediments deposited on the Mendoza Shelf. The formation overlies

54-611: A geologic formation goes back to the beginnings of modern scientific geology. The term was used by Abraham Gottlob Werner in his theory of the origin of the Earth, which was developed over the period from 1774 to his death in 1817. The concept became increasingly formalized over time and is now codified in such works as the North American Stratigraphic Code and its counterparts in other regions. Geologic maps showing where various formations are exposed at

81-542: A newly designated formation could not be named the Kaibab Formation, since the Kaibab Limestone is already established as a formation name. The first use of a name has precedence over all others, as does the first name applied to a particular formation. As with other stratigraphic units, the formal designation of a formation includes a stratotype which is usually a type section . A type section

108-617: A permanent natural or artificial feature of the geographic area in which they were first described. The name consists of the geographic name plus either "Formation" or a descriptive name. Examples include the Morrison Formation , named for the town of Morrison, Colorado , and the Kaibab Limestone , named after the Kaibab Plateau of Arizona. The names must not duplicate previous formation names, so, for example,

135-519: A private residence. The Cliff House, built as the Morrison family home in 1873, now provides guest lodging. These landmarks represent a distinctive style of construction and are enduring monuments to George Morrison's contributions to Jefferson County's history. Stone for these structures was quarried in his "red sandstone quarry" at the end of the Dakota Hogback near Morrison. Building stone

162-449: Is not a valid lithological basis for defining a formation. The contrast in lithology between formations required to justify their establishment varies with the complexity of the geology of a region. Formations must be able to be delineated at the scale of geologic mapping normally practiced in the region; the thickness of formations may range from less than a meter to several thousand meters. Geologic formations are typically named after

189-500: Is also used informally to describe the odd shapes (forms) that rocks acquire through erosional or depositional processes. Such a formation is abandoned when it is no longer affected by the geologic agent that produced it. Some well-known cave formations include stalactites and stalagmites . Morrison, Colorado Morrison is a home rule municipality in Jefferson County, Colorado , United States. The population

216-560: Is central to the geologic discipline of stratigraphy , and the formation is the fundamental unit of stratigraphy. Formations may be combined into groups of strata or divided into members . Members differ from formations in that they need not be mappable at the same scale as formations, though they must be lithologically distinctive where present. The definition and recognition of formations allow geologists to correlate geologic strata across wide distances between outcrops and exposures of rock strata . Formations were at first described as

243-455: Is ideally a good exposure of the formation that shows its entire thickness. If the formation is nowhere entirely exposed, or if it shows considerably lateral variation, additional reference sections may be defined. Long-established formations dating to before the modern codification of stratigraphy, or which lack tabular form (such as volcanic formations), may substitute a type locality for a type section as their stratotype. The geologist defining

270-814: The LoDaisKa site , it was inhabited for approximately 7,500 years. The Town of Morrison was officially incorporated following a unanimous election on January 9, 1906. Sixty-nine votes were cast. On February 13, 1906, a second election gave the newly created town a board of trustees. The first mayor was Thomas Cowan Morrison, son of the town's founder. The original trustees were Dr. Frank L. Luce, Charles Pike, Jacob Schneider, J.W. McLean, Peter O. Nelson, and Lawrence E. "Lee" LaGrow. Most of those names are well recognized as pioneers in Morrison's history. The new board held its first meeting on February 14, 1906. Morrison's first ordinances were passed in February and March 1906, as

297-625: The Morrison Historic District was listed on the National Register of Historic Places . According to the United States Census Bureau , the town has a total area of 2.2 square miles (5.7 km ), all of it land. Morrison is southwest of Denver and is located on State Highway 470 and Morrison Road. The Morrison postal ZIP code (80465) extends west up Turkey Creek Canyon and south of

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324-697: The Vaca Muerta and is overlain by the Agrio Formation . A typical feature of the Chachao Formation is the dominance of oysters , many of them quite large e.g. Aetostreon latissimun , and others small, e.g. Ceratostreon minos . Different kinds of semi-infaunal soft bottom dwellers and swimming bivalves were recognized. Additional forms are represented by gastropods , ammonites ( Olcostephanus curacoensis ), and ichnofossils such as Thalassinoides sp. Serpulids are represented by

351-683: The Colorado state fossil, Stegosaurus . The Morrison Formation covers parts of thirteen western states and has yielded much of our understanding of the extinct animals that lived in the West so long ago. In 1877, the holotypic remains of the dinosaurs Stegosaurus armatus and Apatosaurus ajax were discovered near Morrison by Arthur Lakes . The majority of these fossils were shipped to Othniel Charles Marsh at Yale's Peabody Museum of Natural History in New Haven, Connecticut. These finds from

378-467: The MNHM reported rare adult Stegosaurus tracks from the Morrison area. A year later the first hatchling Stegosaurus tracks were reported. These fossils are on display at the museum. Cretaceous -age dinosaur tracks and one of Lakes' historic dig sites can still be viewed on what is now known as Dinosaur Ridge east of Morrison. Also located near Morrison is a significant archaeological site ; known as

405-819: The Morrison area figured in the 19th century " Bone Wars " between rival paleontologists Marsh and Edward Drinker Cope . In 1896, the Late Jurassic section of sedimentary rock excavated by Lakes was formally named the Morrison Formation for the town near the prominent outcrops where it was described (Eldridge, 1896). In 1944, a type locality was designated at the roadcut along the north side of W. Alameda Parkway, 2 miles (3 km) north of Morrison, in SE/4 sec. 23, T. 4 S., R. 70 W. (Waldschmidt and LeRoy, 1944). The Morrison Natural History Museum houses and displays some fossils found by Lakes, and museum staff have begun reworking Lakes' original digs at Quarry 10. In 2006,

432-436: The colonial Sarcinella sp. , and the solitary form Parsimonia sp. The highly diverse fauna of the analyzed succession, made up with numerous stenohaline elements such as echinoderm, bryozoa, ammonite as well as serpulids and typical marine pelecypods indicate a fully marine environment. The formation has provided the following fossils: Geological formation A formation must be large enough that it can be mapped at

459-550: The essential geologic time markers, based on their relative ages and the law of superposition . The divisions of the geological time scale were described and put in chronological order by the geologists and stratigraphers of the 18th and 19th centuries. Geologic formations can be usefully defined for sedimentary rock layers, low-grade metamorphic rocks , and volcanic rocks . Intrusive igneous rocks and highly metamorphosed rocks are generally not considered to be formations, but are described instead as lithodemes . "Formation"

486-522: The formation is expected to describe the stratotype in sufficient detail that other geologists can unequivocally recognize the formation. Although formations should not be defined by any criteria other than primary lithology, it is often useful to define biostratigraphic units on paleontological criteria, chronostratigraphic units on the age of the rocks, and chemostratigraphic units on geochemical criteria, and these are included in stratigraphic codes. The concept of formally defined layers or strata

513-488: The original Evergreen Hotel, built by George Morrison in 1874, served as the first home of Sacred Heart College (now Regis University ), and later as the Mt. Morrison Casino, where John Brisben Walker entertained many of the dignitaries he brought to the foothills as part of his promotional enterprises. The Morrison Schoolhouse he built served the town's educational needs from its construction in 1875 until 1955, and stands today as

540-563: The original board began the process of managing the town's affairs. The first set a fiscal year beginning March 1, directed the clerk to certify valuation and the board to levy taxes based thereon, and directed the town treasurer to collect funds from the county treasurer. Pete Morrison , grandson of the town's founder and son of the first mayor, achieved fame during the early 1900s as a cowboy star in silent film , and ultimately had his own studio, Lariat Productions, in Hollywood. In 1976,

567-643: The surface are fundamental to such fields as structural geology , allowing geologists to infer the tectonic history of a region or predict likely locations for buried mineral resources. The boundaries of a formation are chosen to give it the greatest practical lithological consistency. Formations should not be defined by any criteria other than lithology. The lithology of a formation includes characteristics such as chemical and mineralogical composition, texture, color, primary depositional structures , fossils regarded as rock-forming particles, or other organic materials such as coal or kerogen . The taxonomy of fossils

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594-432: The surface or traced in the subsurface. Formations are otherwise not defined by the thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of

621-560: The territorial government under Robert Steele, and an important stop for travelers on the Mt. Vernon Toll Road from Denver to the goldfields of the Rocky Mountains. He became a U.S. citizen on May 22, 1862. George Morrison later moved south to Bear Creek , where he founded the Morrison Stone, Lime, and Town Co., and in 1874 platted the town that became known as Morrison, or briefly as Mt. Morrison. With Gov. John Evans , he

648-510: The town. It thus applies to an area covering approximately 5,000 addresses. Because the Morrison Post Office serves this large area beyond the town boundaries proper, many events and people connected with "Morrison" are actually in unincorporated portions of Jefferson County. The local government features a mayor, town manager and a board of trustees. The town is infamous as a speed trap . Press reports indicate that about half

675-400: Was 396 at the 2020 census . This small foothills settlement is named after George Morrison (April 16, 1822 – June 11, 1895), a builder and businessman who left a mark not only on the town that now bears his name, but on the history of the area. A stonemason who immigrated from Canada to the Mt. Vernon area in 1859, he helped found the town of Mt. Vernon and built the Mt. Vernon House, seat of

702-564: Was also shipped to Denver , where it now comprises parts of the Brown Palace Hotel , Union Station , and "many of Denver's early day mansions". Mount Morrison behind Red Rocks Park is also named after George Morrison. In the late 1800s, an important regional geologic layer of Late Jurassic age, the Morrison Formation , was named after the town of Morrison, and is today famous as the first discovery site of three 150-million-year-old dinosaurs, Apatosaurus , Diplodocus , and

729-665: Was instrumental in bringing the Denver, South Park and Pacific Railroad to Morrison in 1874. As a quarryman, Morrison developed the building stone and other industrial stone (lime, gypsum) of the Morrison/Mt. Vernon area, bringing fame to the region for its high-quality dimension stone . Two of the three stone buildings he built in Morrison, as well as the Mt. Vernon House further north, are still standing; all three surviving buildings are recognized historic sites (National Register of Historic Places, 1976). Before its demolition in 1982,

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