is  a magnitude of an earthquake is always accurate on richter scale?
444812
the richter scale is only as accurate as the agency that maintains it.  but for the most part they are very accurate.  the only reason i could think of as to the mountains is that the quake was close enough to a natural fault line deep in the mountain
746545
There are earthquakes all the time.  Do you mean a destructive one?  That would be the quake that interrupted a game during the 1989 World Series when the Giants were playing at home.  Do you mean one some people just barely felt or noticed?  Earlier this month.  Do you mean one detected only by seismograph?  Probably within the last fifteen minutes.\nThe San Andreas fault runs right through San Francisco Bay, and there are plenty of other active faults in the area.
314759
Yes, it would be more accurate, but the calculations are much harder. Whether it is worth it depends on what you have to do with the information. One thing that happens is 'frame dragging', where a rotating mass drags along space and time with the rotation. We now have a probe in orbit around the earth to measure exactly this phenomenon.
562356
Yes! That is what causes all earthquakes!\n\nIt is a conspiracy!
946669
Earthquakes 10.5 are impossibly big.  Places in America where you get earthquakes as big as 9 only happen along the coast of Alaska.  The biggest earthquake that can happen on the San Andreas is about 8.  Volcanoes in the US are only related to some faults, not all, and they are not interconnected, so one eruption is not related to nor does it cause another.\n\nHere are some basics on earthquakes/volcanism to help you with why this is physically impossible:\n\nEarthquakes: \nIt all comes down to stress and strain from the interaction of different plates, chiefly at the boundaries. It is not 'the plates rubbing together' as many people say; or at least that's a very simplistic view.\n\nPlate tectonics causes stress on the continents and oceans, all over the surface of the earth. In some places, the stress is very small (usually within the plates). Elsewhere, the stress is high, usually where the plates meet each other. Since each plate moves, when two come in contact, the stress each other. They can push on each other and cause compressional stress, they can pull with extensional stress, and they can slide past or shear each other with tensional stress.\n\nFaulting, causing earthquakes, comes from the fact that this stress is building up all the time, but rocks and continents are strong materials. Just like hitting a rock with a small hammer, you do put stress on it, but a small amount. It would take a sledgehammer to put enough strain (effects and accumulation of stress) to build up and cause breakage. In the earth, the area around an active fault builds up strain from the stress of plate tectonics. Most faults become locked, because of this strength, and thus can not release their strain. Away from the fault, the stress produces very small and slow movement of the rock masses as a whole. Eventually, the strain is too much and the rest of the plate has moved too far and the fault releases the strain build-up all at once in a big stress release called an earthquake. This is called the elastic rebound theory, and it explains most (but not all) movements.\n\nThis is why an earthquake's size is relative to the fault size. The bigger the fault, the bigger the strain build up, and the bigger the release in an earthquake. Subduction zones and collision zones, where large portions of plates actually can rub together as a whole, have the really big earthquakes, like the 2004 Sumatra earthquake. In other plate boundaries, the entire plate boundary does not act together, so the faults become spread out and many faults take up the strain from the tectonic stress, like with the San Andreas Fault in California (it only takes up ~3/4 of the stress between the plates).\n\nEarthquakes are really tricky things; there is still so much we need to learn. As of now, there is no way to predict them, but we can say where the danger is highest and about how long between events.\n\nVolcanoes:\nThere are several processes in Plate Tectonics that cause volcanism, but they result in two main types of volcanism.\n\nVolcanism in subduction is caused by volitals, like H2O, CO2. These are carried down by the plate, mainly in the form of weak minerals. These minerals break down with pressure and temperature into stronger minerals that don't contain water and carbon dioxide. The leftover gases and liquids travel into the mantle (the mantle wedge) and hydrate the mantle, causing melting. The melt rises and then... volcano!\n\nThe other main cause is from rising mantle material, which forms decompression melting. Basically, hot mantle is kept from melting by the pressure of the earth at depth. When this material rises, the pressure drops much faster than the temperature, and thus it partially melts. This mainly occurs at divergent boundaries and hot spots, which are areas in plate tectonics that have rising materials or spreading.
88180
Yes, to a degree. Earthquakes can be predicted using past locations, active faults, geological recurrence times, and fault slip data rates from plate tectonic and satellite data. This level of prediction is time-independent, so it will only give a likelihood of an earthquake's magnitude with path and locational effects. This is useful for building design, land use planning, and estimating earthquake insurance, but it doesn't predict when it will happen. \n\nMore and more data is being collected on past earthquake movement using trenches dug into faults and measuring the traces of paleomovements. Geodetic instruments are now collecting real-time data on the relative movement of various parts of the continent using satellite measurements. As more data is collected it may become easier to add a time-dependent portion to a prediction. The USGS is posting probabilities like this for some faults, but are often leaving the time period open for 50 or more years. \n\nResearch in the US has mostly focused on better understanding earthquakes, especially after an unsuccessful attempt to monitor precursors and predict an earthquake near Parkfield, California. In Japan there has been a growing realization that earthquake prediction may not be realistic in the aftermath of Kobe. In China approximately 30 false alarms have caused major problems and the government is discouraging predictions. \n\nThere are a number of creative methods that have been proposed such as tidal forces, animal behavior, and alignment of planets, but none of these has any statistically proven validity. In fact, many of these predictions are made so broadly that the normal occurrence of earthquakes tends to make them look successful. \n\nYou might want to read this article in Nature:\nhttp://www.nature.com/nature/debates/earthquake/index.html\nand here is a description of the Parkfield effort:\nhttp://www.geophys.washington.edu/SEIS/PNSN/INFO_GENERAL/eq_prediction.html
1165888
All depends on the magnitude and the location of the earthquake along the fault.
12689
the largest earthquake in the states was about an 8.3. the epicenter was near new madrid, missouri. it hit in 1812... before the richter scale was invented, so we aren't 100% sure what it would measure on that scale.\n\nthe two aftershocks were more destructive than the original quake, though they were not as strong.
55918
An earthquake is the shaking of the ground caused by an abrupt shift of rock along a fracture in the Earth, called a fault. Within seconds, an earthquake releases stress that has slowly accumulated within the rock, sometimes over hundreds of years. ... \nThe size of an earthquake is indicated by a number called its magnitude. Magnitude is calculated from a measurement of either the amplitude or the duration of specific types of recorded seismic waves. Magnitude is determined from measurements made from seismograms and not on reports of shaking or interpretations of building damage. ... The intensity of and earthquake is a measure of the amount of ground shaking at a particular site, and it is determined from reports of human reaction to shaking, damage done to structures, and other effects. ... \n\nEarth scientists believe that most earthquakes are caused by slow movements inside the Earth that push against the Earth's brittle, relatively thin outer layer, causing the rocks to break suddenly. This outer layer is fragmented into a number of pieces, called plates. Most earthquakes occur at the boundaries of these plates. In Washington State, the small Juan de Fuca plate off the coast of Washington, Oregon, and northern California is slowly moving eastward beneath a much larger plate that includes both the North American continent the land beneath part of the Atlantic Ocean. Plate motions in the Pacific Northwest result in shallow earthquakes widely distributed over Washington and deep earthquakes in the western parts of Washington and Oregon. The movement of the Juan de Fuca plate beneath the North America plate is in many respects similar to the movements of plates in South America, Mexico, Japan, and Alaska, where the world's largest earthquakes occur. ...
196324
try using geophysics book as your reference.\np (primary) waves travel on solid, liquid and gas mediums.\nS (shear) waves travel only on solid mediums.\nA proof of this, is an occurrence of earthquakes, is which the quake produces seismic waves and the seismic centers can measure this waves and telling the magnitude of an earthquake.\nIf the earth is hollow, they (siesmologists) couldn't measure the magnitude of earthquakes.
1062718
Earthquakes happen every day around the world.  I'm sure there is a likely hood of an earthquake happening on June 20.  If someone is really into those predictions, they will re-interpretate the prediction after the fact to mean some other location or bla bla blah.
1147777
The strongest recorded earthquake was the chilean earthquake in '64 I think.  It registered 9.6 on the Richter.  The Good Friday quake in alaska registered 9.4, though was still horribly destructive.
758992
Dear friend, There are different people using different methods to predict the occurrence of earthquakes. I know most of the methods and its concept. I am working in development of early warning system for earth quake and Tsunami. I am using the data’s already found by our seismologist. So for we are unable to find the correct method for prediction of earthquakes. Because it depends upon so many factors. That is why the prediction announced by professor My Venkatanathan of Madras University failed. Some time the warning becomes real. But most of the times the prediction failed. For that those who are working in the field of prediction and warning system should share their knowledge with each other. Even though my waning proved real 2 times because I issued the warning 2 hours before tsunami struck our Indian coast to local T.V.Stations on 26th Dec 2004 and I issued the denial of Tsunami attack on 28th March 2005 .For both the incidents I have fool proof records. But nobody came forward to find the fact of my claims. Now after about 22 months our Government run T.V . Station accepted my claims.Please visit my slide show at URL:-\nhttp://asia.pg.photos.yahoo.com/ph/quake
250606
Richter Scale is not a machine. It is the system used to measure the strength of an earthquake. Developed by Charles Richter in 1935 as a means of categorizing local earthquakes. It is a collection of mathematical formulas; it is not a physical device. It is a logarithmic scale for measuring earthquake magnitude which means that, a magnitude 7.0 earthquake generates 10 times larger amplitude waves than those of a magnitude 6.0, and releases 32 times more energy. The machine that measures earthquakes is called a Seismograph.
270342
That depends on the plates, and it varies.  You can't really say US gets the most because Asia has had just as bad earthquakes in different regions over time.  \n\nI found a map of the unstable plates... pretty informative ... check it out:\n\nhttp://library.thinkquest.org/21988/earthquake/earthquake.htm
336125
It is 1000 times stronger. The richter scale is an exponential scale. So from 1 to 2 is 10 times worse.
1041920
The scientists are saying that a "big one" is going to happen. It's not a question of "if", its "when." And they don't know when, it is still, unfortuneatley, impossible to predict earthquakes. They have specials on this topic on the Discovery Channel, so check out your local listings so you can see. I think there's even a movie. Anyways, there is also a huge fault by Washington.