Snakehead (fish)

http://www.biodiversitypartners.org/state/fl/snakehead.shtml.
. Like the herbicides, Rotenone will be sprayed on and into the water from boats. A recently proposed theory suggests that some earthquakes may occur in a sort of earthquake storm, where one earthquake will trigger a series of earthquakes each triggered by the previous shifts on the fault lines, similar to aftershocks, but occurring years later. Dead fish are removed daily; however, unpleasant odors from decaying organic material are to be expected. These oscillations of the earth are either due to the deformation of the Earth by tide caused by the Moon or the Sun, or other phenomena. Approximately one to two weeks after the application of the herbicides, application of the piscicide Rotenone eliminates remaining fish.
Another type of movement of the Earth is observed by terrestrial spectroscopy.

The herbicides are sprayed on and into the water from boats. Earthquakes such as these, that are caused by human activity, are referred to by the term induced seismicity. These chemicals cause oxygen levels to drop, and a subsequent fish kill occurs. Thus scientists have been able to monitor, using the tools of seismology, nuclear weapons tests performed by governments that were not disclosing information about these tests along normal channels. When the process begins, officials will apply the herbicides diquat dibromide and glyphosate (tradenames such as Roundup, Rodeo) to the pond to eliminate aquatic vegetation. Finally, ground shaking can also result from the detonation of explosives. They have also been spotted in Washington, California, Texas, Alabama, Florida, North Carolina, Virginia, Rhode Island, Maine, Massachusetts, and Pennsylvania. Earthquakes have also been known to be caused by the removal of natural gas from subsurface deposits, for instance in the northern Netherlands.

In July 2005 a snakehead was spotted in the waters of Flushing Meadows Park in Queens, New York City. Such earthquakes occur because the strength of the Earth's crust can be modified by fluid pressure. On October 9, 2004 a fisherman caught one in Lake Michigan at Burnham Harbor in Chicago, Illinois. at certain geothermal power plants and at the Rocky Mountain Arsenal). Courtenay. A rare few earthquakes have been associated with the build-up of large masses of water behind dams, such as the Kariba Dam in Zambia, Africa, and with the injection or extraction of fluids into the Earth's crust (e.g. W. Some earthquakes are also caused by the movement of magma in volcanoes, and such quakes can be an early warning of volcanic eruptions.

A comprehensive work on the dangers of the introduction of snakeheads to non-indigeneous waters is the work of Prof. Deep focus earthquakes, at depths of 100's km, are possibly generated as subducted lithospheric material catastrophically undergoes a phase transition since at the pressures and temperatures present at such depth elastic strain cannot be supported. Some examples of the introduction of snakeheads to non-indigeneous waters include:. Eventually when enough stress accumulates, the plates move, causing an earthquake. Due to this fact it was introduced either on purpose (fisheries motivation) or by ignorance (as was the case in Crofton). Where these plates meet stress accumulates. In parts of Asia and Africa, the snakehead is considered a valuable food fish and is produced in aquacultures. The Earth is made up of tectonic plates driven by the heat in the Earth's mantle and core.

Humans have been introducing snakeheads to non-indigenous waters for over 100 years. Most earthquakes are powered by the release of the elastic strain that accumulate over time, typically, at the boundaries of the plates that make up the Earth's lithosphere via a process called Elastic-rebound theory. They are prohibited in several other countries like Australia because their introduction to new ecosystems may displace indigenous species. For example it has been calculated that the average recurrence for the United Kingdom can be described as follows:. Snakehead fish became infamous in the US because of their appearance in a pond in Crofton, Maryland (2002). Larger earthquakes occur less frequently than smaller earthquakes, the relationship being exponential, ie roughly ten times as many earthquakes larger than 4 occur in a particular time period than earthquakes larger than magnitude 5. Snakeheads prompting fears that it could become an invasive species and cause ecological damage. As a result the moment magnitude (M_W) scale was introduced by Hiroo Kanamori, which is comparable to the other magnitude scales but will not saturate at higher values.

. The values of moments for different earthquakes ranges over several order of magnitude. Snakeheads are also sold as pets. The seismic moment is calculated from seismograms but can also by obtained from geologic estimates of the size of the fault rupture and the displacement. Only two species (Channa marulius and Channa micropeltes) can reach a length of more than 1 meter and a weight of more than 6 kilograms. Seismologists now favor a measure called the seismic moment, related to the concept of moment in physics, to measure the size of a seismic source. Most snakeheads grow up to 2 or 3 ft. They are still useful however as they can be rapidly calculated, there are catalogues of them dating back many years and are they are familiar to the public.

So-called dwarf snakeheads like Channa gachua grow to 10 inch maximum. However as each is also based on the measurement of one part of the seismogram they do not measure the overall power of the source and can suffer from saturation at higher magnitude values (larger events fail to produce higher magnitude values).These scales are also empirical and as such there is no physical meaning to the values. The size of the snakehead species differs greatly. Each of these is scaled to gives values similar to the values given by the Richter scale. In rare cases, small mammals such as rats are taken. Other more recent Magnitude measurements include: body wave magnitude (m_b), surface wave magnitude (M_s) and duration magnitude (M_D). When an adult, it mostly feeds on other fish or frogs. It is obtained by measuring the maximum amplitude of a recording on a Wood-Anderson torsion seismometer (or one calibrated to it) at a distance of 600km from the earthquake.

The snakehead feeds on plankton, aquatic insects, and mollusks when small. This is known as the “Richter scale”, “Richter Magnitude” or “Local Magnitude” (M_L). Larger species like Channa striata, Channa maculata or Parachanna obscura are breed in aqua cultures. Richter devised a simple numerical scale (which he called the magnitude) to describe the relative sizes of earthquakes in Southern California. In both continents, they are considered a valuable food fish. In the 1930s, a California seismologist named Charles F. It does so with its suprabranchial organ which is a primitive form of a labyrinth organ. The first attempt to qualitatively define one value to describe the size of earthquakes was the magnitude scale (the name being taking from similar formed scales used on the brightness of stars).

One of its main features is its physiological necessity to breath atmospheric air. If you feel an earthquake in the US you can report the effects to the USGS. The predatory fish is distinguished by a long dorsal fin, small head with large head scales on top, large mouth and teeth. For some tasks related to engineering and local planning it is still useful for the very same reasons and thus still collected. A family with two genera (Asia: Channa, Africa: Parachanna) which consists of 30 scientific valid species of freshwater fish. The problem with these scales is the measurement is subjective, often based on the worst damage in an area and influenced by local effects like site conditions that make it a poor measure for the relative size of different events in different places. Student writes article on Snakehead problem in Florida. No structural damage.

ITIS entry. Damage is slight in poorly built buildings. Overview of Northern Snakehead biology. Trees and bushes shake. snakeheads.org world's largest website for snakeheads. Plaster in walls might crack. Its introduction to Czechoslovakia by the government in the 1960s failed due to cold winters. Furniture moves.

It was introduced to Japan about 100 years ago due to fisheries motivations. Pictures fall off walls. Channa argus, which is native to northern China (Amur River), was introduced to Central Asia (Kazakhstan, Turkmenistan, Uzbekistan). Objects fall from shelves. In this case the origin and reason of the introduction is unknown, but most probably due to human intervention. People have trouble walking. Channa asiatica, which is native to southern China, was introduced to Taiwan and to southern Japan. Everyone feels movement.

In Fiji, the introduction failed. The value 6 (normally denoted "VI") in the MM scale for example is:. Channa striata was introduced to islands east of the Wallace line by governmental programs in the later half of the 20th century. These assign a numeric value (different for each scale) to a location based on the size of the shaking experienced there. It can still be found there today. In the United States the Mercalli (or Modified Mercalli, MM) scale is commonly used, while Japan (shindo) and the EU (European Macroseismic Scale) each have their own scales. Channa maculata was introduced to Madagascar and to Hawaii around the end of the 19th century. The first method of quantifying earthquakes was intensity scales.

Earthquakes that occur below sea level and have large vertical displacements can give rise to tsunamis, either as a direct result of the deformation of the sea bed due to the earthquake or as a result of submarine landslips or "slides" directly or indirectly triggered by it. Just as a large loudspeaker can produce a greater volume of sound than a smaller one, large faults are capable of higher magnitude earthquakes than smaller faults are. The total size of the fault that slips, the rupture zone, can be as large as 1000 km, for the biggest earthquakes. The location on the surface directly above the hypocenter is known as the "epicenter".

That point is called its "focus" or "hypocenter" and usually proves to be the point at which the fault slip was initiated. Using such ground motion records from around the world it is possible to identify a point from which the earthquake's seismic waves appear to originate. The Rayleigh waves from the Sumatra-Andaman Earthquake of 2004 caused ground motion of over 1 cm even at the seismometers that were located far from it, although this displacement was abnormally large. Ground motions caused by very distant earthquakes are called teleseisms.

The power of an earthquake is distributed over a significant area, but in the case of large earthquakes, it can spread over the entire planet. While almost all earthquakes have aftershocks, foreshocks are far less common occurring in only about 10% of events. Most large earthquakes are accompanied by other, smaller ones, that can occur either before or after the principal quake — these are known as foreshocks or aftershocks, respectively. S-waves (secondary or shear waves) and the two types of surfaces waves (Love waves and Rayleigh waves) are responsible for the shaking hazard.

There are four types of seismic waves that are all generated simultaneously and can be felt on the ground. In a particular earthquake, any of these agents of damage can dominate, and historically each has caused major damage and great loss of life, but for most of the earthquakes shaking is the dominant and most widespread cause of damage. liquefaction, landslide), and fire or a release of hazardous materials. Large earthquakes can cause serious destruction and massive loss of life through a variety of agents of damage, including fault rupture, vibratory ground motion (i.e., shaking), inundation (e.g., tsunami, seiche, dam failure), various kinds of permanent ground failure (e.g.

Some deep earthquakes may be due to the transition of olivine to spinel, which is more stable in the deep mantle. At subduction zones where plates descend into the mantle, earthquakes have been recorded to a depth of 600 km, although these deep earthquakes are caused by different mechanisms than the more common shallow events. Where the crust is thicker and colder they will occur at greater depths and the opposite in areas that are hot. Most earthquakes occur in narrow regions around plate boundaries down to depths of a few tens of kilometres where the crust is rigid enough to support the elastic strain.

Large numbers of earthquakes occur on a daily basis on Earth, but the majority of them are detected only by seismometers and cause no damage . . Seismic waves including some strong enough to be felt by humans can also be caused by explosions (chemical or nuclear), landslides, and collapse of old mine shafts, though these sources are not strictly earthquakes. Most earthquakes are tectonic, but they also occur in volcanic regions and as the result of a number of anthropogenic sources, such as reservoir induced seismicity, mining and the removal or injection of fluids into the crust.

Earthquakes related to plate tectonics are called tectonic earthquakes. Events located at plate boundaries are called interplate earthquakes; the less frequent events that occur in the interior of the lithospheric plates are called intraplate earthquakes (see, for example, New Madrid Seismic Zone). The highest stress (and possible weakest zones) are most often found at the boundaries of the tectonic plates and hence these locations are where the majority of earthquakes occur. Earthquakes occur where the stress resulting from the differential motion of these plates exceeds the strength of the crust.

The Earth's lithosphere is a patch work of plates in slow but constant motion (see plate tectonics). The word earthquake is also widely used to indicate the source region itself. Earthquakes typically result from the movement of faults, planar zones of deformation within the Earth's upper crust. Earthquakes result from the dynamic release of elastic strain energy that radiates seismic waves.

An earthquake is a sudden and sometimes catastrophic movement of a part of the Earth's surface. Lake Tanganyika earthquake (2005). Many more at risk from the Kashmiri winter. Killed over 79,000 people.

Kashmir earthquake (2005). Fukuoka earthquake (2005). Sumatran Earthquake (2005). Triggered a tsunami which caused nearly 300,000 deaths spanning several countries.

Epicenter off the coast of the Indonesian island Sumatra. One of the largest earthquakes ever recorded at 9.0. Indian Ocean Earthquake (2004). Chuetsu Earthquake (2004).

Not large (6.0), but the most anticipated and intensely instrumented earthquake ever recorded and likely to offer insights into predicting future earthquakes elsewhere on similar slip-strike fault structures. Parkfield, California earthquake (2004). Bam Earthquake (2003). Dudley Earthquake (2002).

Gujarat Earthquake (2001). Nisqually Earthquake (2001). Chi-Chi earthquake (1999). Düzce earthquake (1999).

İzmit earthquake (1999) Killed over 17,000 in northwestern Turkey. Killed over 6,400 people in and around Kobe, Japan. Great Hanshin earthquake (1995). Damage showed seismic resistance deficiencies in modern low-rise apartment construction.

Northridge, California earthquake (1994). Revealed necessity of accelerated seismic retrofit of road and bridge structures. Severely affecting Santa Cruz, San Francisco and Oakland in California. Loma Prieta earthquake (1989).

Killed over 25,000. Armenian earthquake (1988). Whittier Narrows earthquake (1987). 8.1 on the Richter Scale, killed over 6,500 people (though it is believed as many as 30,000 may have died, due to missing people never reappearing.).

Great Mexican Earthquake (1985). The official death toll was 255,000, but many experts believe that two or three times that number died. The most destructive earthquake of modern times. Tangshan earthquake (1976).

Caused great and unexpected destruction of freeway bridges and flyways in the San Fernando Valley, leading to the first major seismic retrofits of these types of structures, but not at a sufficient pace to avoid the next California freeway collapse in 1989. Sylmar earthquake (1971). Caused a landslide that buried the town of Yungay, Peru; killed over 40,000 people. Ancash earthquake (1970).

Good Friday Earthquake (1964) Alaskan earthquake. Biggest earthquake ever recorded, 9.5 on Moment magnitude scale. Great Chilean Earthquake (1960). Kamchatka earthquakes (1952 and 1737).

On the Japanese island of Honshu, killing over 140,000 in Tokyo and environs. Great Kanto earthquake (1923). San Francisco Earthquake (1906). Largest earthquake in the Southeast and killed 100.

Charleston earthquake (1886). Fort Tejon Earthquake (1857). New Madrid Earthquake (1811). Lisbon earthquake (1755).

Kamchatka earthquakes (1737 and 1952). Cascadia Earthquake (1700). Deadliest known earthquake in history, estimated to have killed 830,000 in China. Shaanxi Earthquake (1556).

San Andreas Fault. New Madrid Fault Zone. North Anatolian Fault Zone. Hayward Fault Zone.

Calaveras Fault. Alpine Fault. Earthquake prediction. Seismic retrofit.

Household seismic safety. Emergency preparedness. an earthquake of 5.6 or larger every 100 years. an earthquake of 4.7 or larger every 10 years.

an earthquake of 3.7 or larger every 1 year.