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Zuni Sandstone
The Zuni Sandstone is a geologic formation in west-central New Mexico. It marks the southernmost limit of Jurassic fluvial and lacustrine sedimentary formations, which pinch out to leave a single sandstone body. Description The Zuni Sandstone is found south of the I-40 corridor in west-central New Mexico. At about this latitude, the Todilto, Morrison, and Summerville Formations pinch out to leave a Jurassic section that is almost entirely composed of eolian sandstone. This is designated as the Zuni Sandstone, which is thus the lateral equivalent of the combined Entrada and Bluff Formations. At the type section at Dowa Yalaane (Taaiyalone Mesa), the formation consists of about of eolian sandstone corresponding to the Entrada Formation. A break corresponds to the pinched-out Todilto and Summerville Formations. Above this is about of sandstone corresponding to the Bluff Formation. Then comes a break corresponding to the pinch-out of the Recapture Member of the Morrison Form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dowa Yalanne
Dowa Yalanne (Zuni language, Zuni: "Corn Mountain") is a steep mesa southeast of the present Zuni Pueblo, New Mexico, Pueblo of Zuni, on the Zuni Indian Reservation. Plainly visible from the Zuni Pueblo, the mesa is located in McKinley County, New Mexico, McKinley County, New Mexico, and has an elevation of . The mesa is a sacred place for the Zuni people, who fled to the mesa top to escape the Francisco Vásquez de Coronado, Coronado expedition in 1540, and it is closed to outside visitors. History ''Dowa Yalanne'' was settled before European contact. In 1540, Zuni people from the village of ''Hawikuh Ruins, Hawikuu'' fled to the ''Dowa Yalanne'' mesa top to escape the attackers of the Coronado expedition. The 14 structures used as a refuge from the Spaniards between 1540 and 1680 were called ''Heshoda Ayahltona'' ("ancient buildings above"). Before the Pueblo Revolt of 1680, the Zuni lived in six different villages. After the revolt, until 1692, they took refuge in a defen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rock
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of geological detritus (minerals) or biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies (marine snow). Sedimentation may also occur as dissolved minerals precipitate from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cow Springs Sandstone
The Entrada Sandstone is a formation in the San Rafael Group found in the U.S. states of Wyoming, Colorado, northwest New Mexico, northeast Arizona, and southeast Utah. Part of the Colorado Plateau, this formation was deposited during the Jurassic Period sometime between 180 and 140 million years ago in various environments, including tidal mudflats, beaches, and sand dunes. The Middle Jurassic San Rafael Group was dominantly deposited as ergs (sand seas) in a desert environment around the shallow Sundance Sea. Description At its type section at Entrada Point, located in the northern part the San Rafael Swell in Emery County, Utah, the Entrada consists of red silty sandstone and lesser interbedded mudstone and is a slope-forming formation. This part of the Entrada is sometimes described as the "earthy facies". Here the Entrada is overlain by the Curtis Formation, and overlies the Carmel Formation.To the south and east, the Entrada transitions to cliff-forming red or white cro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unconformity (geology)
An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval of time before deposition of the younger layer, but the term is used to describe any break in the sedimentary geologic record. The significance of angular unconformity (see below) was shown by James Hutton, who found examples of Hutton's Unconformity at Jedburgh in 1787 and at Siccar Point in 1788. The rocks above an unconformity are younger than the rocks beneath (unless the sequence has been overturned). An unconformity represents time during which no sediments were preserved in a region or were subsequently eroded before the next deposition. The local record for that time interval is missing and geologists must use other clues to discover that part of the geologic history of that area. The interval of geologic time not represented ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bluff Formation
The Bluff Formation is a geological formation found in the Four Corners area. It was deposited in the late Jurassic Period (geology), Period. Description The Bluff Formation consists of massive wind-deposited (Aeolian processes, eolian) sandstone beds at its type location at Bluff, Utah. These cap the cliffs north of town and are thick. Further to the southeast, the sandstone beds lack high-angle Cross-bedding, cross beds, being dominated instead by horizontal bed forms, and are overlain by mixed sandstone and shale beds of the Recapture Member (stratigraphy), Member. The Recapture Member has been variously assigned either to the overlying Morrison Formation or to the Bluff Formation. The Recapture Member is separated from the Salt Wash Member of the Morrison Formation by the regional J-5 unconformity. History of investigation The formation was first named as the Bluff Sandstone by A.A. Baker, C.H. Dane, and J.B. Reeside, Jr., in 1938. They assigned it to the lower Morrison Form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entrada Formation
The Entrada Sandstone is a formation in the San Rafael Group found in the U.S. states of Wyoming, Colorado, northwest New Mexico, northeast Arizona, and southeast Utah. Part of the Colorado Plateau, this formation was deposited during the Jurassic Period sometime between 180 and 140 million years ago in various environments, including tidal mudflats, beaches, and sand dunes. The Middle Jurassic San Rafael Group was dominantly deposited as ergs (sand seas) in a desert environment around the shallow Sundance Sea. Description At its type section at Entrada Point, located in the northern part the San Rafael Swell in Emery County, Utah, the Entrada consists of red silty sandstone and lesser interbedded mudstone and is a slope-forming formation. This part of the Entrada is sometimes described as the "earthy facies". Here the Entrada is overlain by the Curtis Formation, and overlies the Carmel Formation.To the south and east, the Entrada transitions to cliff-forming red or white crossb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eolianite
Eolianite or aeolianite is any rock formed by the lithification of sediment deposited by aeolian processes; that is, the wind. In common use, however, the term refers specifically to the most common form of eolianite: coastal limestone consisting of carbonate sediment of shallow marine biogenic origin, formed into coastal dunes by the wind, and subsequently lithified. It is also known as kurkar_in_the_Middle_East.html" ;"title="haron Horowitz. ''The Quaternary of ... in the Middle East">haron Horowitz. ''The Quaternary of ... in the Middle East, miliolite in India and Arabia, and grès dunaire in the eastern Mediterranean. eolianite has a hardness of 4.3 and is very dull. Streak is light brown. Description Sayles coined the term in 1931, when he described the dune-shaped hills of Bermuda, consisting of bioclastic grainstones. Thus, Bermuda is considered the type locality for carbonate eolianite facies, with clearly defined cross-bedding, foresets, and topsets. Deposition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Summerville Formation
The Summerville Formation is a geological formation in New Mexico, Colorado, and Utah of the Southwestern United States. It dates back to the Oxfordian stage of the Late Jurassic.Wilcox 2007 Description The formation consists of up to of red mudstone, with thin interbeds of green and red sandstone. The lower portion of the formation shows polygonal desiccation cracks and localized salt-hopper casts while the upper portion contains considerable gypsum, consistent with deposition in a sabkha on the margin of the Sundance Sea.It is exposed in the San Rafael Reef, the Waterpocket Fold, in the Henry Mountains, with additional exposures scattered across the region from the San Rafael Reef to the Paradox Basin, and in north-central New Mexico. The thin bedding is characteristic throughout the formation, but gypsum is not found in the San Juan Basin and some conglomerate is found on the south and southwestern margins of the formation.Lucas and Anderson 1992, p.81 The correlation of late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morrison Formation
The Morrison Formation is a distinctive sequence of Late Jurassic, Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltstone, and limestone and is light gray, greenish gray, or red. Most of the fossils occur in the green siltstone beds and lower sandstones, relics of the rivers and floodplains of the Jurassic period. It is centered in Wyoming and Colorado, with outcrops in Montana, North Dakota, South Dakota, Nebraska, Kansas, the panhandles of Oklahoma and Texas, New Mexico, Arizona, Utah, and Idaho. Equivalent rocks under different names are found in Canada. It covers an area of 1.5 million square kilometers (600,000 square miles), although only a tiny fraction is exposed and accessible to geologists and Paleontology, paleontologists. Over 75% is still buried under the prairie to the east, and much of its western paleogeographic extent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Todilto Formation
The Todilto Formation is a geologic formation in northern New Mexico and southeastern Colorado. It preserves fossils dating back to the Callovian stage of the middle Jurassic period. Description The formation consists of evaporites. It is divided into a lower calcareous shale (the Luciano Mesa Member) up to thick, and an upper gypsum bed (the Tonque Arroyo Member). Based on varve counts in the Luciano Mesa Member, the formation was laid down in a geologically brief period of time, likely in a salina (a coastal body of saline water) that was replenished both by rivers and by seepage or periodic flooding from the Sundance Sea. The varves show a 10 to 13 year periodicity that is interpreted as the solar sunspot cycle, showing that this cycle has existed for at least 160 million years. The contact with the underlying Entrada Formation is very sharp and may indicate the Todilto Sea formed catastrophically from a breach in a barrier between the basin and the Sundance Sea. The pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interstate 40
Interstate 40 (I-40) is a major east–west Interstate Highway running through the south-central portion of the United States. At a length of , it is the third-longest Interstate Highway in the country, after I-90 and I-80. From west to east, it passes through California, Arizona, New Mexico, Texas, Oklahoma, Arkansas, Tennessee, and North Carolina. Its western end is at I-15 in Barstow, California, while its eastern end is at a concurrency of U.S. Route 117 (US 117) and North Carolina Highway 132 (NC 132) in Wilmington, North Carolina. Major cities served by the interstate include Flagstaff, Arizona; Albuquerque, New Mexico; Amarillo, Texas; Oklahoma City, Oklahoma; Little Rock, Arkansas; Memphis, Nashville, and Knoxville in Tennessee; and Asheville, Winston-Salem, Greensboro, Durham, Raleigh, and Wilmington in North Carolina. Much of the western part of I-40, from Barstow to Oklahoma City, parallels or overlays the historic U.S. Route 66. East of Oklaho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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