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Santa Teresa Hills
The Santa Teresa Hills are a range of mountains in Santa Clara County, California, located primarily in the city of San Jose. They separate the San Jose neighborhoods of Almaden Valley to the west and Santa Teresa to the east. Geography The range runs south of San Jose and is about 7 miles long. The New Almaden hills and greater Santa Cruz Mountains span south. Notable peaks include Coyote Peak and Bernal Hill. Notable bodies of water include Santa Teresa Creek, which runs west down through the southern portion of the hills. It soon joins Arroyo Calero, which originates from Calero Reservoir in New Almaden. Arroyo Calero then joins Alamitos Creek, which flows through Almaden Lake at the western end of the Santa Teresa Hills, exiting eventually to the Guadalupe River and then to the San Francisco Bay at Alviso. Santa Teresa Spring emerges at the base of the north side of the hills, in the nearby Santa Teresa County Park. Geology Serpentinized ultramafic rock from the Jura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Clara County, California
Santa Clara County, officially the County of Santa Clara, is the sixth-most populous county in the U.S. state of California, with a population of 1,936,259 as of the 2020 United States census, 2020 census. Santa Clara County and neighboring San Benito County, California, San Benito County form the San Jose–Sunnyvale–Santa Clara metropolitan statistical area, which is part of the larger San Jose–San Francisco–Oakland combined statistical area. Santa Clara is the most populous county in the San Francisco Bay Area and in Northern California. The county seat and largest city with a population of 971,233 is San Jose, California, San Jose, the List of United States cities by population, 13th-most populous city in the nation, List of cities and towns in California, California's third-most populous city, and the List of cities and towns in the San Francisco Bay Area, most populous city in Northern California. Home to Silicon Valley, Santa Clara County is an economic center for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar, because they are the most resistant minerals to the weathering processes at the Earth's surface. Like uncemented sand, sandstone may be imparted any color by impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other topography, topographic features, certain colors of sandstone have become strongly identified with certain regions, such as the red rock deserts of Arches National Park and other areas of the Southwestern United States, American Southwest. Rock formations composed of sandstone usually allow the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolomite (rock)
Dolomite (also known as dolomite rock, dolostone or dolomitic rock) is a sedimentary rock, sedimentary carbonate rock that contains a high percentage of the mineral Dolomite (mineral), dolomite, CaMg(CO3)2. It occurs widely, often in association with limestone and evaporites, though it is less abundant than limestone and rare in Cenozoic rock beds (beds less than about 66 million years in age). One of the first geologists to distinguish dolomite from limestone was Déodat Gratet de Dolomieu, a French mineralogist and geologist after whom it is named. He recognized and described the distinct characteristics of dolomite in the late 18th century, differentiating it from limestone. Most dolomite was formed as a magnesium replacement of limestone or of Lime (mineral), lime mud before lithification. The geological process of conversion of calcite to dolomite is known as dolomitization and any intermediate product is known as dolomitic limestone. The "dolomite problem" refers to the v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury (element)
Mercury is a chemical element; it has Symbol (chemistry), symbol Hg and atomic number 80. It is commonly known as quicksilver. A Heavy metal element, heavy, silvery d-block element, mercury is the only metallic element that is known to be liquid at standard temperature and pressure; the only other element that is liquid under these conditions is the halogen bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature. Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide). The red pigment vermilion is obtained by Mill (grinding), grinding natural cinnabar or synthetic mercuric sulfide. Exposure to mercury and mercury-containing organic compounds is toxic to the nervous system, immune system and kidneys of humans and other animals; mercury poisoning can result from exposure to water-soluble forms of mercury (such as mercuric chloride or methylmercury) either directly or through mechanisms of biomagnification. Mercu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Francisco
San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of 2024, San Francisco is the List of California cities by population, fourth-most populous city in the U.S. state of California and the List of United States cities by population, 17th-most populous in the United States. San Francisco has a land area of at the upper end of the San Francisco Peninsula and is the County statistics of the United States, fifth-most densely populated U.S. county. Among U.S. cities proper with over 250,000 residents, San Francisco is ranked first by per capita income and sixth by aggregate income as of 2023. San Francisco anchors the Metropolitan statistical area#United States, 13th-most populous metropolitan statistical area in the U.S., with almost 4.6 million residents in 2023. The larger San Francisco Bay Area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stanford University
Leland Stanford Junior University, commonly referred to as Stanford University, is a Private university, private research university in Stanford, California, United States. It was founded in 1885 by railroad magnate Leland Stanford (the eighth List of governors of California, governor of and then-incumbent List of United States senators from California, United States senator representing California) and his wife, Jane Stanford, Jane, in memory of their only child, Leland Stanford Jr., Leland Jr. The university admitted its first students in 1891, opening as a Mixed-sex education, coeducational and non-denominational institution. It struggled financially after Leland died in 1893 and again after much of the campus was damaged by the 1906 San Francisco earthquake. Following World War II, university Provost (education), provost Frederick Terman inspired an entrepreneurship, entrepreneurial culture to build a self-sufficient local industry (later Silicon Valley). In 1951, Stanfor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust Fault
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. If the angle of the fault plane is lower (often less than 15 degrees from the horizontal) and the displacement of the overlying block is large (often in the kilometer range) the fault is called an ''overthrust'' or ''overthrust fault''. Erosion can remove part of the overlying block, creating a ''fenster'' (or ''window'') – when the underlying block is exposed only in a relatively small area. When erosion removes most of the overlying block, leaving island-like remnants resting on the lower block, the remnants are called ''klippen'' (singular '' klippe''). Blind thrust faults If the fault plane terminates before it reaches the Earth's surface, it is called a ''blind thrust'' fault. Because of the lack of surface evidence, blind thrust fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, 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 planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, 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 volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, 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 flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chert
Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a precipitation (chemistry), chemical precipitate or a diagenesis, diagenetic replacement, as in petrified wood. Chert is typically composed of the petrified remains of siliceous ooze, the biogenic sediment that covers large areas of the deep ocean floor, and which contains the silicon skeletal remains of diatoms, Dictyochales, silicoflagellates, and radiolarians. Precambrian cherts are notable for the presence of fossil cyanobacteria. In addition to Micropaleontology, microfossils, chert occasionally contains macrofossils. However, some chert is devoid of any fossils. Chert varies greatly in color, from white to black, but is most often found as gray, brown, grayish brown and light green to rusty redW.L. Roberts, T.J. Campbell, G.R. Rapp Jr., ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franciscan Complex
The Franciscan Complex or Franciscan Assemblage is a geology, geologic term for a late Mesozoic terrane of heterogeneous rock (geology), rocks found throughout the California Coast Ranges, and particularly on the San Francisco Peninsula. It was named by geologist Andrew Lawson, who also named the San Andreas Fault that defines the western extent of the assemblage. The Franciscan Complex is dominated by greywacke sandstones, shales and Conglomerate (geology), conglomerates which have experienced low-grade metamorphism. Other important lithologies include chert, basalt, limestone, serpentinite, and high-pressure, low-temperature metabasites (blueschists and eclogites) and meta-limestones. Fossils like radiolaria are found in chert beds of the Franciscan Complex. These fossils have been used to provide age constraints on the different terranes that constitute the Franciscan. The mining opportunities within the Franciscan are restricted to deposits of cinnabar and limestone. The ou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Cretaceous
The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Austral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''Ēṓs'', 'Eos, Dawn') and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.See: *Letter from William Whewell to Charles Lyell dated 31 January 1831 in: * From p. 55: "The period next antecedent we shall call Eocene, from ήως, aurora, and χαινος, recens, because the extremely small proportion of living species contained in these strata, indicates what may be considered the first commencement, or ''dawn'', of the existing state of the animate creation." The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isoto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
