|
Parkfield, California
Parkfield (formerly Russelsville) is an unincorporated community in Monterey County, California. It is located on Little Cholame Creek east of Bradley, at an elevation of . As of 2007, road signs announce the population as 18. Parkfield is located in the Temblor Range between the San Joaquin Valley and the Central Coast, at an elevation of above sea level. Mining and homesteading used to be prosperous activities in this community, but the mines were exhausted below economic recovery levels, and the industry moved elsewhere. Today, Parkfield is a small town of about 18 people, most of whom are ranchers and farmers. There is a small tourism industry in the town based on equine-related events, hunting, a bluegrass music festival, and Parkfield's unique earthquake history (see the Geology section below). The Parkfield motto is, "Be here when it happens." A post office operated at Parkfield from 1884 to 1954. The town's original name of Russelsville was rejected by the post offic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unincorporated Area
An unincorporated area is a region that is not governed by a local municipal corporation. Widespread unincorporated communities and areas are a distinguishing feature of the United States and Canada. Most other countries of the world either have no unincorporated areas at all or these are very rare: typically remote, outlying, sparsely populated or List of uninhabited regions, uninhabited areas. By country Argentina In Argentina, the provinces of Chubut Province, Chubut, Córdoba Province (Argentina), Córdoba, Entre Ríos Province, Entre Ríos, Formosa Province, Formosa, Neuquén Province, Neuquén, Río Negro Province, Río Negro, San Luis Province, San Luis, Santa Cruz Province, Argentina, Santa Cruz, Santiago del Estero Province, Santiago del Estero, Tierra del Fuego Province, Argentina, Tierra del Fuego, and Tucumán Province, Tucumán have areas that are outside any municipality or commune. Australia Unlike many other countries, Australia has only local government in Aus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geologic maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Talc
Talc, or talcum, is a Clay minerals, clay mineral, composed of hydrated magnesium silicate with the chemical formula Mg3Si4O10(OH)2. Talc in powdered form, often combined with corn starch, is used as baby powder. This mineral is used as a thickening agent and lubricant. It is an ingredient in ceramics, paints, and roofing material. It is a main ingredient in many cosmetics. It occurs as Foliation (geology), foliated to Fiber, fibrous masses, and in an exceptionally rare crystal form. It has a perfect cleavage (crystal), basal cleavage and an uneven flat fracture, and it is foliated with a two-dimensional ped, platy form. The Mohs scale of mineral hardness, based on Scratch hardness, scratch hardness comparison, defines value 1 as the hardness of talc, the softest mineral. When scraped on a streak (mineralogy), streak plate, talc produces a white streak; though this indicator is of little importance, because most silicate minerals produce a white streak. Talc is translucent to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serpentinite
Serpentinite is a rock composed predominantly of one or more serpentine group minerals, the name originating from the similarity of the texture of the rock to that of the skin of a snake. Serpentinite has been called ''serpentine'' or ''serpentine rock'', particularly in older geological texts and in wider cultural settings.California Government Code § 425.2; ''see'' Formation and mineralogy Serpentinite is formed by near to complete serpentinization of mafic to ultramafic rocks. Serpentinite can be formed wherever ultramafic rock is infiltrated by water poor in carbon dioxide. This occurs at mid-ocean ridges and in the forearc mantle of subduction zones. The final mineral composition of serpentinite is usually dominated by lizardite, chrysotile, and magnetite. Brucite and antigorite are less commonly present. Lizardite, chrysotile, and antigorite all have approximately the formula or , but differ in minor components and in form. Accessory minerals, present in smal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Andreas Fault Observatory At Depth
The San Andreas Fault Observatory at Depth (SAFOD) is a research project that began in 2002 aimed at collecting geological data about the San Andreas Fault for the purpose of predicting and analyzing future earthquakes. The site consists of a pilot hole and a main hole. Drilling operations ceased in 2007. Located near the town of Parkfield, California, the project has installed geophone sensors and GPS clocks in a borehole that cuts directly through the fault. This data, along with samples collected during drilling, could shed new light on geochemical and mechanical properties around the fault zone. SAFOD is part of Earthscope, an Earth science program using geological and geophysical techniques to explore the structure of the North American continent and to understand the origin of earthquakes and volcanoes. Earthscope is funded by the National Science Foundation in conjunction with the U.S. Geological Survey and NASA. Data collected at SAFOD are available from The Northern Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time Zone
A time zone is an area which observes a uniform standard time for legal, Commerce, commercial and social purposes. Time zones tend to follow the boundaries between Country, countries and their Administrative division, subdivisions instead of strictly following longitude, because it is convenient for areas in frequent communication to keep the same time. All time zones are defined as offsets from Coordinated Universal Time (UTC), ranging from UTC−12:00 to UTC+14:00. The UTC offset, offsets are usually a whole number of hours, but a few zones are offset by an additional 30 or 45 minutes, such as in Indian Standard Time, India, Time in Australia, South Australia and Nepal Time, Nepal. Some areas of higher latitude use daylight saving time for about half of the year, typically by adding one hour to local time during spring (season), spring and summer. List of UTC offsets In the table below, the locations that use daylight saving time (DST) are listed in their UTC offse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moment Magnitude Scale
The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. It was defined in a 1979 paper by Thomas C. Hanks and Hiroo Kanamori. Similar to the local magnitude scale, local magnitude/Richter scale () defined by Charles Francis Richter in 1935, it uses a logarithmic scale; small earthquakes have approximately the same magnitudes on both scales. Despite the difference, news media often says "Richter scale" when referring to the moment magnitude scale. Moment magnitude () is considered the authoritative magnitude scale for ranking earthquakes by size. It is more directly related to the energy of an earthquake than other scales, and does not saturate—that is, it does not underestimate magnitudes as other scales do in certain conditions. It has become the standard scale used by seismological authorities like the U.S. Geological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
US Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredth annivers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simon Winchester
Simon Winchester (born 28 September 1944) is a British-American author and journalist. In his career at ''The Guardian'' newspaper, Winchester covered numerous significant events, including Bloody Sunday and the Watergate Scandal. Winchester has written or contributed to more than a dozen nonfiction books, has written one novel, and has contributed to several travel magazines, among them '' Condé Nast Traveler'', ''Smithsonian Magazine'', and ''National Geographic''. Early life and education Born in London, Winchester attended several boarding schools in Dorset, including Hardye's School. He spent a year hitchhiking around the United States, then in 1963 went up to St Catherine's College, Oxford, to study geology. He graduated in 1966, and found work with Falconbridge of Africa, a Canadian mining company. His first assignment was to work as a field geologist searching for copper deposits in Uganda. Career While on assignment in Uganda, Winchester happened upon a copy of Jame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aseismic Creep
In geology, aseismic creep or fault creep is measurable surface displacement along a fault in the absence of notable earthquakes. Aseismic creep may also occur as "after-slip" days to years after an earthquake. Notable examples of aseismic slip include faults in California (e.g. Calaveras Fault, Hayward Fault, and San Andreas Fault). Causes Aseismic creep accommodates far-field motions on localized zones of deformation at tectonic plate boundaries. The underlying causes of aseismic creep are primarily attributed to poor frictional strength of the fault, low normal stress acting on the fault in the shallow crust, and excessive pore-fluid pressures, which limit the viable amount of normal stress on a fault. The frictional reaction of geologic materials can explain the transition from seismic to aseismic deformation with depth. Friction along faults can cause sudden slips with associated stress drops (earthquakes), along with phases of no motion as stress recharges. Measurements ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
