Morrison

Dinosaur National Monument is a United States National Monument located on the southeast flank of the Uinta Mountains on the border between Colorado and Utah at the confluence of the Green and Yampa Rivers. Although most of the monument area is in Moffat County, Colorado, the Dinosaur Quarry is located in Utah just to the north of the town of Jensen, Utah. The nearest communities are Jensen, Utah, and Dinosaur, Colorado. The park contains over 800 paleontological sites and has fossils of dinosaurs including Allosaurus, Deinonychus, Abydosaurus (a nearly complete skull, lower jaws and first four neck vertebrae of the specimen DINO 16488 found here at the base of the Mussentuchit Member of the Cedar Mountain Formation is the holotype for the description) and various long-neck, long-tail sauropods. It was declared a National Monument on October 4, 1915. The rock layer enclosing the fossils is a sandstone and conglomerate bed of alluvial or river bed origin known as the Morrison Formation from the Jurassic Period some 150 million years old. The dinosaurs and other ancient animals were carried by the river system which eventually entombed their remains in Utah. The pile of sediments were later buried and lithified into solid rock. The layers of rock were later uplifted and tilted to their present angle by the mountain building forces that formed the Uintas during the Laramide orogeny. The relentless forces of erosion exposed the layers at the surface to be found by paleontologists. The dinosaur fossil beds (bone beds) were discovered in 1909 by Earl Douglass, a paleontologist working and collecting for the Carnegie Museum of Natural History. He and his crews excavated thousands of fossils and shipped them back to the museum in Pittsburgh, Pennsylvania for study and display. President Woodrow Wilson proclaimed the dinosaur beds as Dinosaur National Monument in 1915. The monument boundaries were expanded in 1938 from the original 80-acre (320,000 m2) tract surrounding the dinosaur quarry in Utah, to its present extent of over 200,000 acres (800 km²) in Utah and Colorado, encompassing the spectacular river canyons of the Green and Yampa. Though lesser-known than the fossil beds, the petroglyphs in Dinosaur National Monument are another treasure the monument holds. Due to problems with vandals, many of the sites are not listed on area maps. The "Wall of Bones" located within the Dinosaur Quarry building in the park consists of a steeply tilted (67° from horizontal) rock layer which contains hundreds of dinosaur fossils. The enclosing rock has been chipped away to reveal the fossil bones intact for public viewing. In July 2006, the Quarry Visitor Center was closed due to structural problems that since 1957 had plagued the building because it was built on unstable clay. The decision was made to build a new facility elsewhere in the monument to house the visitor center and administrative functions, making it easier to resolve the structural problems of the quarry building while still retaining a portion of the historic Mission 66 era exhibit hall. It was announced in April 2009 that Dinosaur National Monument would receive $13.1 million to refurbish and reopen the gallery as part of the Obama administration's $750 billion stimulus plan. The Park Service successfully rebuilt the Quarry Exhibit Hall, supporting its weight on 70-foot steel micropile columns that extend to the bedrock below the unstable clay. The Dinosaur Quarry was reopened in Fall 2011. en.wikipedia.org/wiki/Dinosaur_National_Monument en.wikipedia.org/wiki/Wikipedia:Text_of_Creative_Commons_...

Life restoration of Tanycolagreus topwilsoni. Based on Figure 2.16 of "New small theropod from the Upper Jurassic Morrison Formation of Wyoming" by Kenneth Carpenter, Clifford Miles, and Karen Cloward (The Carnivorous Dinosaurs pp. 23-48, Indiana University Press).

Brontosaurus excelsus in the Yale Peabody Museum of Natural History. Brontosaurus excelsus Inv no. YPM 1980 (holotype specimen of the species) Discoverer William H. Reed 1879 Locality Como Bluff, Wyoming Age Morrison Formatian, Jurassic period, 150 million years ago

Morrison Formation (lower half), Jurassic-Cretacous boundary (K1 Unconformity) at red and orange paleosol, Cedar Mountain Formation (drab gray), and capping Naturita Formation. West of Dinosaur National Monument.

Brushy Basin Member of the Morrison Formation (multi-colored) unconformably overlain by the Yellow Cat Member of the Cedar Mountain Formation (drab color), Jessie's Twist, Emery County, Utah

View east towards the Quarry Visitor Center at Dinosaur National Monument. The boundary between the Morrison Formation (Brushy Basin Member) and the Cedar Mountain Formation is just above the highest red bed.

Typical exposure of the Cedar Mountain Formation overlying the Morrison Formation, south of Green River Utah

Paleogeography and paleoclimate of the Late Jurassic - 150 Ma with dinosaur fossil localities: A = Tendaguru Formation, Tanzania C1 = Shishugou & Kalazha Formations, China C2 = Shangshaximiao (Upper Shaximiao) Formation, China E1 = Sables de Glos, Argiles d’Octeville, Marnes de Bléville, Kimmeridge Clay, Calcareous Grit, Corallian Oolite, Oxford Clay, Portland Stone, England & France E2 = Villar del Arzobispo, Alcobaça, Guimarota, Sobral, Amoreira-Porto Novo, Bombarral, Freixial, Lourinhã Formations, Spain & Portugal M1-6 = Morrison Formation, United States S1 = Toquí & Cañadón Calcáreo Formations, Chile & Argentina

The distictive banding of the Morrison Formation, a group of rock layers that occur throughout Dinosaur National Monument. The formation originated as muds and sands laid down by ancient rivers, and some of its outcrops have been found to contain 150-million-year-old dinosaur fossils like those found at the monument's Dinosaur Quarry.

Drawings of Dryolestida left upper−molar, modified from the original descriptions. A–C, Kimmeridgian; D–F, Tithonian–Berriasian; G–H, early Barremian; I, late Barremian. A. Left M4 or M5 of Comotherium richi Prothero, 1981, from the Upper Jurassic Morrison Formation, Como Bluff locality, Wyoming, USA. B. Right M5, reversed, of Dryolestes leiriensis Martin, 1999, from Guimarota, Portugal.C. Left M6 of Krebsotherium lusitanicum Martin, 1999, from Guimarota, Portugal. D. Right M4 or M 6 (reversed) of Portopinheirodon asymmetricus Martin, 1999, Porto Pinheiro, Lourinha, Portugal. E. Right M5 (reversed) of Laolestes andresi Martin, 1999, from Porto Pinheiro, Lourinha, Portugal. F. Right upper molar of Donodon perscriptoris Sigogneau−Russell, 1991, Anoual, Morocco.G. Left M4 orM5 of Crusafontia amoae sp. nov., holotype, Cuesta Corrales 2, El Castellar Formation, Galve, Teruel, Spain. H. Right M6 orM7 (reversed) of Crusafontia amoae sp. nov., first described as upper molar of Crusafontia cuencana by Krebs (1993), P−2 H4 Pelejón 2, Galve, Teruel, Spain. I. Left M2 or M3, of Crusafontia cuencana Henkel and Krebs, 1969, Uña, La Huérguina Formation, Cuenca, Spain, (from Krebs 1993). Scale bars 1 mm.

Left ilium of Stokesosaurus clevelandi, Madsen 1974 (UMNH VP 7473), Morrison Formation, Utah, USA, Late Jurassic (early Tithonian).

Camarasaurus lentus (Marsh, 1889) sauropod dinosaur from the Jurassic of Utah, USA (public display, CM 11338, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA). This is a near-complete juvenile sauropod dinosaur in the original fluvial sandstone matrix - such skeletons are extremely rare. Classification: Animalia, Chordata, Vertebrata, Dinosauria, Sauropodomorpha, Camarasauridae Stratigraphy: Brushy Basin Member, Morrison Formation, Upper Jurassic, 151 Ma Locality: Carnegie Quarry, Dinosaur National Monument, northeastern Utah, USA Sauropod dinosaurs were the largest terrestrial animals ever. They all have the same basic body plan: large body with four walking legs, very long neck & tail, and a small head relative to body size. Sauropods were herbivores, and are often perceived as holding their heads & necks up high to reach vegetation normally out of reach to other organisms. Modern reconstructions of many sauropod species depict them with heads and necks held close to the horizontal, or at low angles above the horizontal.

Camarasaurus lentus (Marsh, 1889) sauropod dinosaur from the Jurassic of Utah, USA (public display, CM 11338, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA). This is a near-complete juvenile sauropod dinosaur in the original fluvial sandstone matrix - such skeletons are extremely rare. Classification: Animalia, Chordata, Vertebrata, Dinosauria, Sauropodomorpha, Camarasauridae Stratigraphy: Brushy Basin Member, Morrison Formation, Upper Jurassic, 151 Ma Locality: Carnegie Quarry, Dinosaur National Monument, northeastern Utah, USA Sauropod dinosaurs were the largest terrestrial animals ever. They all have the same basic body plan: large body with four walking legs, very long neck & tail, and a small head relative to body size. Sauropods were herbivores, and are often perceived as holding their heads & necks up high to reach vegetation normally out of reach to other organisms. Modern reconstructions of many sauropod species depict them with heads and necks held close to the horizontal, or at low angles above the horizontal.

Camarasaurus lentus (Marsh, 1889) sauropod dinosaur from the Jurassic of Utah, USA (public display, CM 11338, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA). This is a near-complete juvenile sauropod dinosaur in the original fluvial sandstone matrix - such skeletons are extremely rare. Classification: Animalia, Chordata, Vertebrata, Dinosauria, Sauropodomorpha, Camarasauridae Stratigraphy: Brushy Basin Member, Morrison Formation, Upper Jurassic, 151 Ma Locality: Carnegie Quarry, Dinosaur National Monument, northeastern Utah, USA Sauropod dinosaurs were the largest terrestrial animals ever. They all have the same basic body plan: large body with four walking legs, very long neck & tail, and a small head relative to body size. Sauropods were herbivores, and are often perceived as holding their heads & necks up high to reach vegetation normally out of reach to other organisms. Modern reconstructions of many sauropod species depict them with heads and necks held close to the horizontal, or at low angles above the horizontal.

Camarasaurus lentus (Marsh, 1889) sauropod dinosaur from the Jurassic of Utah, USA (public display, CM 11338, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA). This is a near-complete juvenile sauropod dinosaur in the original fluvial sandstone matrix - such skeletons are extremely rare. Classification: Animalia, Chordata, Vertebrata, Dinosauria, Sauropodomorpha, Camarasauridae Stratigraphy: Brushy Basin Member, Morrison Formation, Upper Jurassic, 151 Ma Locality: Carnegie Quarry, Dinosaur National Monument, northeastern Utah, USA Sauropod dinosaurs were the largest terrestrial animals ever. They all have the same basic body plan: large body with four walking legs, very long neck & tail, and a small head relative to body size. Sauropods were herbivores, and are often perceived as holding their heads & necks up high to reach vegetation normally out of reach to other organisms. Modern reconstructions of many sauropod species depict them with heads and necks held close to the horizontal, or at low angles above the horizontal.