Franciscan Assemblage or Franciscan Complex is a geologic term for a late Mesozoic terrane of heterogeneous rocks found throughout the California Coast Ranges, on the San Francisco Peninsula. It was named by geologist Andrew Lawson, who named the San Andreas fault that defines the western extent of the assemblage. Identified by its red-green color and folded, twisted appearance, the assemblage is characterized as being metamorphic in nature, its most well-known rocks are blueschists. However, the assemblage contains a wide range of different rocks in different stages of the rock cycle. A single outcrop may contain basalt and other rocks in addition to schist; the outcrops of the formation have a large range, extending from Douglas County, Oregon to Santa Barbara County, California. Franciscan-like formations may be as far south as Santa Catalina Island; the formation lends its name to the term describing high-pressure regional metamorphic facies, the Franciscan facies series. These rocks - which are known as the Franciscan Complex, Series, or Group - include mafic volcanic rocks, many of which are altered to greenstone, radiolarian cherts, greywacke sandstones, serpentinites and high-pressure metamorphic rocks, such as blueschist.
Although most of the Franciscan is Late Jurassic through Cretaceous in age, some Franciscan rocks as young as Miocene, as old as early Jurassic age are known. Following deposition, these rocks were faulted and mixed in a chaotic manner. Due to the lack of continuous exposures and the complex folding and faulting, it is impossible to use conventional methods to estimate the thickness of the assemblage. However, various arguments can be made. Franciscan rocks are thought to have formed prior to creation of the San Andreas Fault when an ancient deep-sea trench existed along the California continental margin; this trench, most of, no longer evident, resulted from subduction of oceanic crust of the Farallon tectonic plate beneath continental crust of the North American Plate. As oceanic crust descended beneath the continent, volcanic rocks basalt, making up the lower plate, marine sediments deposited on top of it were scraped off and accreted to the leading edge of the overriding plate; this resulted in widespread deformation with development of folding.
Ophiolite, rocks altered by high-pressure metamorphism were emplaced during this episode. Deformation and emplacement continued during subsequent creation of the San Andreas fault to result in a complex chaotic assemblage of diverse rock types that some refer to as a mélange. Franciscan sediments contain a diverse assemblage of fossils; the most abundant fossils by far are microfossils in the cherts, which contain single-celled organisms called radiolarians that have exoskeletons of silica. There are in some of the shales microfossils of planktonic foraminifera that have exoskeletons of carbonate; these microfossils, by and large, indicate deposition in an open-water setting where deep-water conditions exist. Vertebrate fossils in the Franciscan are rare, but include three Mesozoic marine reptiles that are shown in the table below. Again, these indicate an open-water, therefore deep-marine setting. Although rare, a few shallow-marine fossils have been found as well, include extinct oysters and clams.
Microfossils in the Calera Limestone member of the Franciscan exposed at the Permanente and Pacifica cement quarries indicate a shallow-marine setting, with deposition on top of a seamount in the tropical Pacific Ocean and subsequent transport and accretion by the Pacific Plate onto the California continental margin. Thus though most of the Franciscan appears to have been deposited in a deep-water setting, it is a complex and diverse assemblage of rocks, shallow-water settings, though not the norm, existed as well. Although no significant accumulations of oil or gas have been found in the Franciscan, other opportunities have been exploited over the years. During the 19th century when gold mining was one of the main industries in California, cinnabar associated with serpentine in the Franciscan was mined for quicksilver needed to process gold ore and gold-bearing gravels; some of the more important mines were those at New Idria and New Almaden, the Sulphur Bank Mine at Clearlake Oaks, the Knoxville Mine and others at Knoxville.
The Franciscan contains large bodies of limestone pure enough for making cement, the Permanente Quarry near Cupertino, California is a giant open-pit mine in a body of Franciscan limestone that supplied most of the cement for building the Shasta Dam across the Sacramento River. The Rockaway Beach Quarry at Pacifica is another example of a major limestone quarry in the Franciscan. California landslides Farallon Plate – An ancient oceanic plate that has subducted under the west coast of the North American Plate Great Valley Sequence – A group of late Mesozoic formations in the Cental Valley of California Subduction – A geological process at convergent tectonic plate boundaries where one plate moves under the other Bailey, E. H.. P.. L.. "Franciscan and related rocks and their significance in the geology of western California". California Div. Mines and Geology Bull. 183: 177 p. Blome, C. D.. P.. "Tectonic significance of late Paleozoic to Jurassic radiolarians from the North Fork terrane, Klamath Mountains, California".
In Stevens, C. H. Pre-Jurassic rocks in we
Escherichia coli known as E. coli, is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus Escherichia, found in the lower intestine of warm-blooded organisms. Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in their hosts, are responsible for product recalls due to food contamination. The harmless strains are part of the normal microbiota of the gut, can benefit their hosts by producing vitamin K2, preventing colonization of the intestine with pathogenic bacteria, having a symbiotic relationship. E. coli is expelled into the environment within fecal matter. The bacterium grows massively in fresh fecal matter under aerobic conditions for 3 days, but its numbers decline afterwards. E. Coli and other facultative anaerobes constitute about 0.1% of gut microbiota, fecal–oral transmission is the major route through which pathogenic strains of the bacterium cause disease. Cells are able to survive outside the body for a limited amount of time, which makes them potential indicator organisms to test environmental samples for fecal contamination.
A growing body of research, has examined environmentally persistent E. coli which can survive for extended periods outside a host. The bacterium can be grown and cultured and inexpensively in a laboratory setting, has been intensively investigated for over 60 years. E. coli is a chemoheterotroph whose chemically defined medium must include a source of carbon and energy. E. coli is the most studied prokaryotic model organism, an important species in the fields of biotechnology and microbiology, where it has served as the host organism for the majority of work with recombinant DNA. Under favorable conditions, it takes up to 20 minutes to reproduce. E. coli is a facultative anaerobic and nonsporulating bacterium. Cells are rod-shaped, are about 2.0 μm long and 0.25–1.0 μm in diameter, with a cell volume of 0.6–0.7 μm3. E. Coli stains Gram-negative because its cell wall is composed of a thin peptidoglycan layer and an outer membrane. During the staining process, E. coli picks up the color of the counterstain safranin and stains pink.
The outer membrane surrounding the cell wall provides a barrier to certain antibiotics such that E. coli is not damaged by penicillin. Strains that possess flagella are motile; the flagella have a peritrichous arrangement. It attaches and effaces to the microvilli of the intestines via an adhesion molecule known as intimin. E. coli can live on a wide variety of substrates and uses mixed-acid fermentation in anaerobic conditions, producing lactate, ethanol and carbon dioxide. Since many pathways in mixed-acid fermentation produce hydrogen gas, these pathways require the levels of hydrogen to be low, as is the case when E. coli lives together with hydrogen-consuming organisms, such as methanogens or sulphate-reducing bacteria. Optimum growth of E. coli occurs at 37 °C, but some laboratory strains can multiply at temperatures up to 49 °C. E. coli grows in a variety of defined laboratory media, such as lysogeny broth, or any medium that contains glucose, ammonium phosphate monobasic, sodium chloride, magnesium sulfate, potassium phosphate dibasic, water.
Growth can be driven by aerobic or anaerobic respiration, using a large variety of redox pairs, including the oxidation of pyruvic acid, formic acid and amino acids, the reduction of substrates such as oxygen, fumarate, dimethyl sulfoxide, trimethylamine N-oxide. E. coli is classified as a facultative anaerobe. It uses oxygen when it is available, it can, continue to grow in the absence of oxygen using fermentation or anaerobic respiration. The ability to continue growing in the absence of oxygen is an advantage to bacteria because their survival is increased in environments where water predominates; the bacterial cell cycle is divided into three stages. The B period occurs between the beginning of DNA replication; the C period encompasses the time it takes to replicate the chromosomal DNA. The D period refers to the stage between the conclusion of DNA replication and the end of cell division; the doubling rate of E. coli is higher. However, the length of the C and D periods do not change when the doubling time becomes less than the sum of the C and D periods.
At the fastest growth rates, replication begins before the previous round of replication has completed, resulting in multiple replication forks along the DNA and overlapping cell cycles. E. coli and related bacteria possess the ability to transfer DNA via bacterial conjugation or transduction, which allows genetic material to spread horizontally through an existing population. The process of transduction, which uses the bacterial virus called a bacteriophage, is where the spread of the gene encoding for the Shiga toxin from the Shigella bacteria to E. coli helped produce E. coli O157:H7, the Shiga toxin-producing strain of E. coli. E. coli encompasses an enormous population of bacteria that exhibit a high degree of both genetic and phenotypic diversity. Genome sequencing of a large number of isolates of E. coli and related bacteria shows that a taxonomic reclassification would be desirable. However, this has not been done due to its medical importance, E. coli remains one of the most diverse bacterial species: only 20% of the genes in a typical E. coli genome is shared among all strains.
In fact, from the evolutionary point of view, the members of genus Shigella (S. dysenteriae, S. fle
An estuary is a enclosed coastal body of brackish water with one or more rivers or streams flowing into it, with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments, they are subject both to marine influences—such as tides and the influx of saline water—and to riverine influences—such as flows of fresh water and sediment. The mixing of sea water and fresh water provide high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are classified according to their geomorphological features or to water-circulation patterns, they can have many different names, such as bays, lagoons, inlets, or sounds, although some of these water bodies do not meet the above definition of an estuary and may be saline.
The banks of many estuaries are amongst the most populated areas of the world, with about 60% of the world's population living along estuaries and the coast. As a result, many estuaries suffer degradation from a variety of factors including: sedimentation from soil erosion from deforestation and other poor farming practices; the word "estuary" is derived from the Latin word aestuarium meaning tidal inlet of the sea, which in itself is derived from the term aestus, meaning tide. There have been many definitions proposed to describe an estuary; the most accepted definition is: "a semi-enclosed coastal body of water, which has a free connection with the open sea, within which sea water is measurably diluted with freshwater derived from land drainage". However, this definition excludes a number of coastal water bodies such as coastal lagoons and brackish seas. A more comprehensive definition of an estuary is "a semi-enclosed body of water connected to the sea as far as the tidal limit or the salt intrusion limit and receiving freshwater runoff.
This broad definition includes fjords, river mouths, tidal creeks. An estuary is a dynamic ecosystem having a connection to the open sea through which the sea water enters with the rhythm of the tides; the sea water entering the estuary streams. The pattern of dilution varies between different estuaries and depends on the volume of fresh water, the tidal range, the extent of evaporation of the water in the estuary. Drowned river valleys are known as coastal plain estuaries. In places where the sea level is rising relative to the land, sea water progressively penetrates into river valleys and the topography of the estuary remains similar to that of a river valley; this is the most common type of estuary in temperate climates. Well-studied estuaries include the Severn Estuary in the United Kingdom and the Ems Dollard along the Dutch-German border; the width-to-depth ratio of these estuaries is large, appearing wedge-shaped in the inner part and broadening and deepening seaward. Water depths exceed 30 m.
Examples of this type of estuary in the U. S. are the Hudson River, Chesapeake Bay, Delaware Bay along the Mid-Atlantic coast, Galveston Bay and Tampa Bay along the Gulf Coast. Bar-built estuaries are found in place where the deposition of sediment has kept pace with rising sea level so that the estuaries are shallow and separated from the sea by sand spits or barrier islands, they are common in tropical and subtropical locations. These estuaries are semi-isolated from ocean waters by barrier beaches. Formation of barrier beaches encloses the estuary, with only narrow inlets allowing contact with the ocean waters. Bar-built estuaries develop on sloping plains located along tectonically stable edges of continents and marginal sea coasts, they are extensive along the Atlantic and Gulf coasts of the U. S. in areas with active coastal deposition of sediments and where tidal ranges are less than 4 m. The barrier beaches that enclose bar-built estuaries have been developed in several ways: building up of offshore bars by wave action, in which sand from the sea floor is deposited in elongated bars parallel to the shoreline, reworking of sediment discharge from rivers by wave and wind action into beaches, overwash flats, dunes, engulfment of mainland beach ridges due to sea level rise and resulting in the breaching of the ridges and flooding of the coastal lowlands, forming shallow lagoons, elongation of barrier spits from the erosion of headlands due to the action of longshore currents, with the spits growing in the direction of the littoral drift.
Barrier beaches form in shallow water and are parallel to the shoreline, resulting in long, narrow estuaries. The average water depth is less than 5 m, exceeds 10 m. Examples of bar-built estuaries are Barnegat Bay, New Jersey. Fjords were formed where pleistocene glaciers deepened and widened existing river valleys so that they become U-shaped in cross s
The Pacific Ocean is the largest and deepest of Earth's oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean in the south and is bounded by Asia and Australia in the west and the Americas in the east. At 165,250,000 square kilometers in area, this largest division of the World Ocean—and, in turn, the hydrosphere—covers about 46% of Earth's water surface and about one-third of its total surface area, making it larger than all of Earth's land area combined; the centers of both the Water Hemisphere and the Western Hemisphere are in the Pacific Ocean. The equator subdivides it into the North Pacific Ocean and South Pacific Ocean, with two exceptions: the Galápagos and Gilbert Islands, while straddling the equator, are deemed wholly within the South Pacific, its mean depth is 4,000 meters. The Mariana Trench in the western North Pacific is the deepest point in the world, reaching a depth of 10,911 meters; the western Pacific has many peripheral seas. Though the peoples of Asia and Oceania have traveled the Pacific Ocean since prehistoric times, the eastern Pacific was first sighted by Europeans in the early 16th century when Spanish explorer Vasco Núñez de Balboa crossed the Isthmus of Panama in 1513 and discovered the great "southern sea" which he named Mar del Sur.
The ocean's current name was coined by Portuguese explorer Ferdinand Magellan during the Spanish circumnavigation of the world in 1521, as he encountered favorable winds on reaching the ocean. He called it Mar Pacífico, which in both Portuguese and Spanish means "peaceful sea". Important human migrations occurred in the Pacific in prehistoric times. About 3000 BC, the Austronesian peoples on the island of Taiwan mastered the art of long-distance canoe travel and spread themselves and their languages south to the Philippines and maritime Southeast Asia. Long-distance trade developed all along the coast from Mozambique to Japan. Trade, therefore knowledge, extended to the Indonesian islands but not Australia. By at least 878 when there was a significant Islamic settlement in Canton much of this trade was controlled by Arabs or Muslims. In 219 BC Xu Fu sailed out into the Pacific searching for the elixir of immortality. From 1404 to 1433 Zheng He led expeditions into the Indian Ocean; the first contact of European navigators with the western edge of the Pacific Ocean was made by the Portuguese expeditions of António de Abreu and Francisco Serrão, via the Lesser Sunda Islands, to the Maluku Islands, in 1512, with Jorge Álvares's expedition to southern China in 1513, both ordered by Afonso de Albuquerque from Malacca.
The east side of the ocean was discovered by Spanish explorer Vasco Núñez de Balboa in 1513 after his expedition crossed the Isthmus of Panama and reached a new ocean. He named it Mar del Sur because the ocean was to the south of the coast of the isthmus where he first observed the Pacific. In 1519, Portuguese explorer Ferdinand Magellan sailed the Pacific East to West on a Spanish expedition to the Spice Islands that would result in the first world circumnavigation. Magellan called the ocean Pacífico because, after sailing through the stormy seas off Cape Horn, the expedition found calm waters; the ocean was called the Sea of Magellan in his honor until the eighteenth century. Although Magellan himself died in the Philippines in 1521, Spanish Basque navigator Juan Sebastián Elcano led the remains of the expedition back to Spain across the Indian Ocean and round the Cape of Good Hope, completing the first world circumnavigation in a single expedition in 1522. Sailing around and east of the Moluccas, between 1525 and 1527, Portuguese expeditions discovered the Caroline Islands, the Aru Islands, Papua New Guinea.
In 1542–43 the Portuguese reached Japan. In 1564, five Spanish ships carrying 379 explorers crossed the ocean from Mexico led by Miguel López de Legazpi, sailed to the Philippines and Mariana Islands. For the remainder of the 16th century, Spanish influence was paramount, with ships sailing from Mexico and Peru across the Pacific Ocean to the Philippines via Guam, establishing the Spanish East Indies; the Manila galleons operated for two and a half centuries, linking Manila and Acapulco, in one of the longest trade routes in history. Spanish expeditions discovered Tuvalu, the Marquesas, the Cook Islands, the Solomon Islands, the Admiralty Islands in the South Pacific. In the quest for Terra Australis, Spanish explorations in the 17th century, such as the expedition led by the Portuguese navigator Pedro Fernandes de Queirós, discovered the Pitcairn and Vanuatu archipelagos, sailed the Torres Strait between Australia and New Guinea, named after navigator Luís Vaz de Torres. Dutch explorers, sailing around southern Africa engaged in discovery and trade.
In the 16th and 17th centuries Spain considered the Pacific Ocean a mare clausum—a sea closed to other naval powers. As the only known entrance from the Atlantic, the Strait of Magellan was at times patrolled by fleets sent to prevent entrance of non-Spanish ships. On the western side of the Pacific Ocean the Dutch threatened the Spanish Philippines; the 18th cen
Crannell is a former settlement in Humboldt County, California. It is located 4.5 miles southeast of Trinidad, at an elevation of 203 feet. The location was a company town for sawmill workers of the Little River Redwood Company, organized in 1893 by owners in Ottawa and western New York. Company headquarters were in Tonawanda; the California sawmill commenced operations in 1908. The post office opened in 1909 was named for property owner Conrad Bulwinkle. In 1922 the community was renamed for Little River Redwood Company president Levi Crannell; the town was served by the Trinidad extension of the Northwestern Pacific Railroad from 1911 to 1933. The Hammond-Little River Redwood Company, Ltd. was formed in a 1931 merger with Hammond Lumber Company. Crannell was called Camp Nine by the Hammond Lumber Company; the Humboldt Northern Railway connection to Samoa, California was dismantled in 1948. Hammond became a subsidiary of Georgia-Pacific Corporation in 1956. Worker housing was razed in 1969, but the site remained in use as an equipment storage and maintenance base for forestry operations of subsequent landowners.
The site was transferred to Louisiana-Pacific Corporation during a Federal Trade Commission action initiated in 1972. Simpson Timber Company purchased the property on June 30, 1998, subsequently became Green Diamond Resource Company around 2004. Green Diamond refers to the forested land as "Crannell Tree Farm"
Little River State Beach
Not to be confused with LIttle River beach in Van Damme State Park, Mendocino County, California Little River State Beach is a protected beach of California, United States, in Humboldt County. It is located at the mouth of the Little River, 13 miles north of Eureka right off U. S. Route 101; the 152-acre park was established in 1931. The site is a open beach that contains sand dunes; the Little River forms the north boundary of the beach. It is open for day-use only. List of beaches in California List of California state parks Parks in Humboldt County, California Little River State Beach