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Forearm and hand of Machairasaurus leptorhynchos Longrich et al. 2010 (Dinosauria: Theropoda: Oviraptoridae: Ingeniinae) from the Late Cretaceous Djadokhta Formation beds of Bayan Mandahu, Inner Mongolia, China. Digital photography and editing by Nick Longrich

New wing skeleton of Forfexopterus (SDUST-V1003) from Jiufotang Formation of Early Cretaceous Jehol Biota in Jianchang, western Liaoning, northeastern China. Abbreviations: ca, carpus; co, coracoid portion; hu, humerus; mc, metacarpals I–IV; mdI–III, manual digits I–III; pt, pteroid; ra, radius; sc, scapular portion; ul, ulna; wp1–4, wing phalanges 1–4.

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_...

Right hind limb of the sauropodomorph dinosaur Musankwa sanyatiensis gen. et sp. nov. (NHMZ 2521) from the Pebbly Arkose Formation (Norian, Upper Triassic) of Spurwing Island, Zimbabwe. A. Right femur in posterior (A1), lateral (A2), anterior (A3), medial (A4), proximal (A5), and distal (A6) views. B. Right tibia with conjoined astragalus in anterior (B1), lateral (B2), posterior (B3), medial (B4), and proximal (B5) views.

Life restoration of the Triassic ichthyosaur Callawayia neoscapularis. Three specimens of this ichthyosaur are known, the holotype, ROM 41993, and two referred specimens, TMP 94.380.11 and 94.382.2. The skull is primarily based on ROM 41993, cross-checked against TMP 94.380.11 and TMP 94.382.2. The vertebral column is based primarily on TMP 94.382.2 as it is the most complete of these specimens, while the ribs were based on ROM 41993. The forelimbs were mainly based on those of ROM 41993, with TMP 94.380.11 used to determine their breadth. The hindlimbs were based on TMP 94.380.11, especially the more complete right hindlimb. ROM 41993 was cross-scaled with TMP 94.380.11 by the dimensions of the forelimb epipodials, which produced similar vertebral dimensions. The two TMP specimens were cross-scaled based on femoral length, also producing similar vertebral dimensions. Nicholls & Manabe (2001) stated that no wedge-shaped caudal centra supporting a tailbend were found and that there was no evidence of a bend being present, though considered that they might have existed in the gap in the preserved caudals. Since various other Triassic ichthyosaurs have since been found to have tail bends, one was illustrated here. A modest downturn of roughly 15° was illustrated, comparable to that in Guanlingsaurus, and the location of the bend within the gap in the preserved vertebrae matches well with the location of the bend in Guizhouichthyosaurus. References McGowan, C. (1994). "A new species of Shastasaurus (Reptilia: Ichthyosauria) from the Triassic of British Columbia: The most complete exemplar of the genus". Journal of Vertebrate Paleontology 14 (2): 168–179. DOI:10.1080/02724634.1994.10011550. Nicholls, E. L.; Manabe, M. (2001). "A new genus of ichthyosaur from the Late Triassic Pardonet Formation of British Columbia: Bridging the Triassic-Jurassic gap". Canadian Journal of Earth Sciences 38 (6): 983–1002. Ji, C.; Jiang, D.Y.; Hao, W.; Sun, Y. (2011). "True tailbend occurred in the Late Triassic: Evidence from ichthyosaur skeletons of South China". Acta Scientiarum Naturalium Universitatis Pekinensis 47 (2): 309–314. Shang, Q. H.; Li, C. (2009). "On the occurrence of the ichthyosaur Shastasaurus in the Guanling biota (Late Triassic), Guizhou, China". Vertebrata PalAsiatica 47 (3): 178–193.

Barsboldia sicinskii gen. et sp.n., type specimen ZPAL MgD-11110, Nemegt Formation, N Nemegt, Nemegt Basin, Gobi Desert, Mongolia 1. Right lateral view of sacrum, neural spine of last dorsal and two anterior caudals included.

Tetrapodosaurus borealis footprint from the Dunvegan Formation, Canada.

Reconstructed skeleton of Tenontosaurus, from the Cloverly Formation.

Fossil specimen of Ornithomimus sp. (TMP 1995.110.1), Royal Tyrrell Museum. This specimen was recovered from the middle Dinosaur Park Formation of Alberta, Canada.

Untere Sulfatschichten, Heilbronn-Formation, Mittlerer Muschelkalk, Löwenburg bei Braunsbach-Geislingen

Zechstein unconformity and basal Zechstein beds (basal Werra-Formation, lower Upper Permian) including copper shale (brownish weathered), exposed on the upper level of the open cast mine Kamsdorf, near Saalfeld, Thuringia, Germany.

Banded fine-grained pyrite in shale from the Precambrian of Australia. (public display, Leadville Mining Museum, Leadville, Colorado, USA) A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 4900 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates. The sulfide minerals contain one or more sulfide anions (S-2). The sulfides are usually considered together with the arsenide minerals, the sulfarsenide minerals, and the telluride minerals. Many sulfides are economically significant, as they occur commonly in ores. The metals that combine with S-2 are mainly Fe, Cu, Ni, Ag, etc. Most sulfides have a metallic luster, are moderately soft, and are noticeably heavy for their size. These minerals will not form in the presence of free oxygen. Under an oxygen-rich atmosphere, sulfide minerals tend to chemically weather to various oxide and hydroxide minerals. Pyrite is a common iron sulfide mineral (FeS2). It’s nickname is “fool's gold”. Pyrite has a metallic luster, brassy gold color (in contrast to the deep rich yellow gold color of true gold - www.flickr.com/photos/jsjgeology/sets/72157651325153769/), dark gray to black streak, is hard (H=6 to 6.5), has no cleavage, and is moderately heavy for its size. It often forms cubic crystals or pyritohedrons (crystals having pentagonal faces). Pyrite is common in many hydrothermal veins, shales, coals, various metamorphic rocks, and massive sulfide deposits. The rock shown above consists of numerous bands of fine-grained pyrite interbedded with dark shale. Published research has shown that the pyrite is diagenetic, formed by sulfate reduction from sulfate-bearing groundwater that moved along bedding planes of the Urquhart Shale host rocks (see Painter et al., 1999). The sulfate source was evaporitic gypsum-anhydrite-barite in the same stratigraphic unit. Stratigraphy: Urquhart Shale, Mount Isa Group, Mesoproterozoic, ~1655 Ma Age of metamorphism: peak greenschist-facies metamorphism at ~1505 Ma during the Isan Orogeny Locality: Mount Isa Mines, northwestern Queensland, northeastern Australia Some info. from: Kawasaki & Symons (2010) - Dating of Mesoproterozoic metamorphism in the Mount Isa and George Fisher Zn-Pb-Cu-Ag deposits, Australia, by paleomagnetism. American Geophysical Union, Fall Meeting 2010, Abstract GP33C-0953. Painter et al. (1999) - Sedimentologic, petrographic, and sulfur isotope constraints on fine-grained pyrite formation at Mount Isa Mine and environs, northwest Queensland, Australia. Economic Geology 94: 883-912. Photo gallery of pyrite: www.mindat.org/gallery.php?min=3314

Banded iron formation from the Precambrian of Wyoming, USA. (~10.9 cm across at its widest) Banded iron formations, or BIFs, are unusual, dense sedimentary rocks consisting of alternating layers of iron-rich oxides and iron-rich silicates. Most BIFs are Proterozoic in age (although some are Late Archean), and do not form today - they're “extinct”! Many specific varieties of iron formation are known, and some are given special rock names. For example, jaspilite is an attractive reddish & silvery gray banded rock consisting of hematite, red chert (“jasper”), and specular hematite or magnetite. Because of their age, most BIFs have been around long enough to have been subjected to one or more orogenic (mountain-building) events. As such, most BIFs are folded and/or metamorphosed to varying degrees. BIFs are known from around the world, but some of the most famous & extensive BIF deposits are found in the vicinity of North America’s Lake Superior Basin. Many BIFs have economic concentrations of iron and are mined. BIFs are the most important variety of iron ore on Earth. Some iron mines in west-central Wyoming exploit BIFs in the Goldman Meadows Formation, a Mesoarchean unit exposed in the Wind River Range. These rocks have been multiply metamorphosed during the Precambrian. The result of this metamorphism is highly contorted folding and fracturing. The rock shown above is a folded quartz-hematite-limonite meta-BIF. Stratigraphy: iron formation member (probably the upper iron formation member) of the Goldman Meadows Formation, upper Mesoarchean, 2.87 Ga (metamorphosed in the Archean at 2.8 Ga and in the Mesoproterozoic at 1.4 Ga) Geologic context: northwestern flank of the South Pass Greenstone Belt, southern Wind River Range Locality: Atlantic City Iron Mine (open-pit mine; sample possibly collected from tailings piles around the now-flooded pit) (E1/2 of section 26, T30N, R100W, Miners Delight 7.5' USGS topographic quadrangle), South Pass-Atlantic City Mining District, along Rt. 28, southwestern side of South Pass, north of Atlantic City, southwestern Fremont County, west-central Wyoming, USA (mine is at 42° 32' 45" North latitude, 108° 44' 33" West longitude)

This artist's concept shows a celestial body about the size of our moon slamming at great speed into a body the size of Mercury. NASA's Spitzer Space Telescope found evidence that a high-speed collision of this sort occurred a few thousand years ago around a young star, called HD 172555, still in the early stages of planet formation. The star is about 100 light-years from Earth.

J. D. Porfiri excavating the holotype of Diuqin lechiguanae from the Bajo de la Carpa Formation.

Outcrops of the Foremost Formation along the Milk River.