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Fifes Peaks Formation
Description Fifes Peaks Formation consists of flows that are vesicular, basaltic andesite. Weathering the rock creates shades of dark brown. The newly fractured blocks are medium- to dark-gray colors. Some flows are fine grained, most are porphyritic and contain glassy phenocrysts of plagioclase that weather to chalky-appearing clay. The flows are a few feet to several tens of feet (3–20 m), with columnar jointing common in the thicker flows.Simmons, George C., USGS, and Ronald M. Van Noy and Nicholas T. Zilka; Mineral Resources of the Cougar Lakes-Mount Aix Study Area, Yakima and Lewis Counties, Washington; Geological Survey Bulletin 1504-A; U.S. Bureau of Mines; General Printing Office; Washington, D.C. The breccias in the Fifes Peak are mostly shades of gray, purple, and red, with angular to subrounded rock fragments cemented by ash. The fragments are a few inches in dimension, rarely a foot long. They are mostly andesite porphyry, pumice, and glass. With fewer rock fragme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness (geology), 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 a geologic formation goes back to the beginnings of modern scientific geology. The term was used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vesicular Texture
Vesicular texture is a volcanic rock texture characterized by a rock being pitted with many cavities (known as vesicles) at its surface and inside. This texture is common in aphanitic, or glassy, igneous rocks that have come to the surface of the earth, a process known as extrusion. As magma rises to the surface the pressure on it decreases. When this happens gasses dissolved in the magma are able to come out of solution, forming gas bubbles (the cavities) inside it. When the magma finally reaches the surface as lava and cools, the rock solidifies around the gas bubbles and traps them inside, preserving them as holes filled with gas called vesicles. A related texture is amygdaloidal in which the volcanic rock, usually basalt or andesite, has cavities, or vesicles, that are filled with secondary minerals, such as zeolites, calcite, quartz, or chalcedony. Individual cavity fillings are termed amygdules (American usage) or amygdales (British usage). Sometimes these can be s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Aix
Mount Aix is a mountain summit centrally located in the William O. Douglas Wilderness on land administered by the Wenatchee National Forest, and is the highest point in that wilderness area. It is also 24 miles east-southeast of Mount Rainier in Yakima County of Washington state. Mount Aix is situated east of the crest of the Cascade Range, southeast of Bumping Lake, north of Bismarck Peak, and northwest of Rimrock Lake. Its nearest higher peak is Tieton Peak in the Goat Rocks Wilderness, to the south-southwest. Mount Aix is the highest peak in the entire region which is east of Mount Rainier National Park, north of Goat Rocks Wilderness, west of Yakima, and south of Mount Daniel (Alpine Lakes Wilderness), so it is quite prominent. Prior to 1897 (when Mount Aix was officially recognized by the USGS) the name was spelled as Mount Aiks on early survey maps and publications. Climate Mount Aix is located east of the Cascade crest. Most weather fronts originate in the Pacific Ocea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cougar Mountain
Cougar Mountain is a peak in the Issaquah Alps in King County, Washington. It is part of the highlands in the Eastside suburbs of Seattle, and at it is the lowest and westernmost of the Alps. About two-thirds of Cougar Mountain has experienced residential development, and is home to many neighborhood communities such as Lakemont. The forested heart of the hill was officially preserved by King County in June 1983 as Cougar Mountain Regional Wildland Park. Cougar Mountain is home to the Cougar Mountain Zoo. Geology Cougar Mountain was formed in the Miocene when tectonic forces folded western Washington along a northwest axis and created the Newcastle Anticline. The anticline exposed earlier (Eocene to Oligocene) sedimentary and volcanic rocks that, due to erosion, now form the surface of Cougar Mountain. The northern edge of Cougar Mountain is distinct due to the Seattle Fault, which runs along I-90. The Seattle Fault caused a large earthquake approximately 1100 years ago. Ec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ... Epoch. The Oligocene is the third and final epoch of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rimrock Lake
Rimrock Lake is a lake along the course of the Tieton River, in Yakima County, Washington state, US. The lake is used as a storage reservoir for the Yakima Project, an irrigation project run by the United States Bureau of Reclamation. An impoundment of the Tieton River, Rimrock Lake's capacity and discharge is controlled by Tieton Dam, a 319-foot (97 m) high structure built in 1925. Rimrock Lake's active capacity is .Yakima Project . Upstream from the lake, the Tieton River is impounded by Clear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White River (Puyallup River)
The White River is a white, glacial river in the U.S. state of Washington. It flows about 75 miles (121 km) from its source, the Emmons Glacier on Mount Rainier, to join the Puyallup River at Sumner. It defines part of the boundary between King and Pierce counties. Course The source of the White River is the Emmons Glacier on the northeast side of Mount Rainier. The river flows from ice caves at the toe of the glacier. Its upper reach is contained within Mount Rainier National Park. Shortly after emerging from the Emmons Glacier, the White River flows generally east, by the White River Campground, then the White River Ranger Station, after which it turns north. The river is paralleled by much of its upper course by State Route 410, called the Mather Memorial Parkway in the national park. After several miles the river exits Mount Rainier National Park and enters Mount Baker-Snoqualmie National Forest. The river turns gradually westward, passing several national forest cam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suntop Lookout
Suntop Lookout (also Sun Top) is located on Suntop Mountain in Mount Baker-Snoqualmie National Forest in central Washington, USA. The fire lookout is at an elevation of about overlooking the valleys of the White River and Huckleberry Creek just to the north of Mount Rainier National Park. Built to standard U.S. Forest Service plans, the one-story ground-level lookout measures fourteen by fourteen feet. The frame structure is capped by a pyramidal roof, and features large windows on all four sides with pivoting shutters that act as sunshades. The Suntop lookout was built in either 1932 or 1933 to standard plans for an "L-4 Lookout House." It is one of two intact lookouts from the period in the former Snoqualmie National Forest. The lookout was used during World War II in the U.S. Army Aircraft Warning System. It is open to the public in summer months. The lookout was listed on the National Register of Historic Places on July 14, 1987. In Popular Culture A work within the SCP Fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breccias
Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of different origins, as indicated by the named types including sedimentary breccia, tectonic breccia, igneous breccia, impact breccia, and hydrothermal breccia. A megabreccia is a breccia composed of very large rock fragments, sometimes kilometers across, which can be formed by landslides, impact events, or caldera collapse. Types Breccia is composed of coarse rock fragments held together by cement or a fine-grained matrix. Like conglomerate, breccia contains at least 30 percent of gravel-sized particles (particles over 2mm in size), but it is distinguished from conglomerate because the rock fragments have sharp edges that have not been worn down. These indicate that the gravel was deposited very close to its source area, since otherwise t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basaltic
Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of Venus, which cover ~80% of the surface, are basaltic; the lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flows that can spread over great areas before cooling and solidifying. Flood basalts are thick se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andesitic
Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained ( aphanitic) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende. Andesite is the extrusive equivalent of plutonic diorite. Characteristic of subduction zones, andesite represents the dominant rock type in island arcs. The average composition of the continental crust is andesitic. Along with basalts, andesites are a component of the Martian crust. The name ''andesite'' is derived from the Andes mountain range, where this rock type is found in abundance. It was first applied by Christian Leopold von Buch in 1826. Description Andesite is an aphanitic (fine-grained) igneous rock that is intermediate in its content of silica and low in alkali metals. It has less than 20% quartz and 10% feldspathoid by volume, with at least 65% of the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass
Glass is a non-Crystallinity, crystalline, often transparency and translucency, transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of the Melting, molten form; some glasses such as volcanic glass are naturally occurring. The most familiar, and historically the oldest, types of manufactured glass are "silicate glasses" based on the chemical compound silicon dioxide, silica (silicon dioxide, or quartz), the primary constituent of sand. Soda–lime glass, containing around 70% silica, accounts for around 90% of manufactured glass. The term ''glass'', in popular usage, is often used to refer only to this type of material, although silica-free glasses often have desirable properties for applications in modern communications technology. Some objects, such as drinking glasses and glasses, eyeglasses, are so commonly made of silicate- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
