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What type of stress did the 1902 san francisco earthquake have?
The great San Francisco earthquake happened in 1906 and not in 1902. The type of stress was a strike-slip stress.
How do scientists measures earthquakes?
Scientists normally use something called the Richter scale to measure earthquakes. They measure in maginitude. 1 on the Richter scale would be small vibrations through the earthquake zone where as 10 would be total destruction. Hope that's helped!
How is magnitude and intensity scale in earthquakes different?
Magnitude regards the size of the event of phenomena, whereas intensity refers to amounts over time. Intensity is akin to frequency. For example when measuring earthquakes, Richter scale gauges its force through magnitude, and its intensity is frequency of resonation felt.
How do scientists study earthquakes?
With a really big ruler! No, not quite. There are two ways in which scientists quantify the size of earthquakes: magnitude and intensity. Magnitude is a measure of the amount of energy released during an earthquake, and you've probably heard news reports about earthquake magnitudes measured using the Richter scale. Something like, "A magnitude 7.3 earthquake struck Japan today. Details at ten." Did you ever wonder why, if it's that important, they just don't tell you right away? The Richter scale was invented, logically enough, in the 1930s by Dr. Charles Richter, a seismologist at the California Institute of Technology. It is a measure of the largest seismic wave recorded on a particular kind of seismograph located 100 kilometers (about 62 miles) from the epicenter of the earthquake. Think of a seismograph as a kind of sensitive pendulum that records the shaking of the Earth. The output of a seismograph is known as a seismogram. In the early days, seismograms were produced using ink pens on paper or beams of light on photographic paper, but now it's most often done digitally using computers. The seismograph that Dr. Richter used amplified movements by a factor of 3000, so the waves on the seismograms were much bigger than those that actually occurred in the Earth. The epicenter of an earthquake is the point on the Earth's surface directly above the source, or focus, of the movement that causes the quake. Dr. Richter studied records from many earthquakes in southern California, and realized that some earthquakes made very small waves whereas others produced large waves. So, to make it easier to compare the sizes of the waves he recorded, Richter used the logarithms of the wave heights on seismograms measured in microns (1/1,000,000th of a meter, or 1/1000th of a millimeter). Remember, you have to be using a particular kind of seismograph located 100 km from the epicenter when you make the measurement; otherwise, all sorts of complicated calculations have to be made. That's why seismologists spend so many years in college! A wave one millimeter (1000 microns) high on a seismogram would have a magnitude of 3 because 1000 is ten raised to the third power. In contrast, a wave ten millimeters high would have a magnitude of 4. For reasons that we won't go into, a factor of 10 change in the wave height corresponds to a factor of 32 change in the amount of energy released during the earthquake. In other words, a magnitude 7 earthquake would produce seismogram waves 10 x 10 = 100 times as high and release energy 32 x 32 = 1024 times as great as a magnitude 5 earthquake. The Richter scale is open-ended, meaning there is no limit to how small or large an earthquake might be. Due to the nature of logarithms, it is even possible to have earthquakes with negative magnitudes, although they are so small that humans would never feel them. At the other end of the spectrum, there should never be an earthquake much above magnitude 9 on the Earth simply because it would require a fault larger than any on the planet. The largest earthquake ever recorded on Earth was a magnitude 9.5 that occurred in Chile in 1960, followed in size by the 1964 Good Friday earthquake in Alaska (magnitude 9.2), a magnitude 9.1 earthquake in Alaska during 1957, and a magnitude 9.0 earthquake in Russia during 1952. Two large earthquakes, one a magnitude 9.0 and one a magnitude 8.2, occurred on Dec. 26, 2004 and March 28, 2005, respectively, along the same fault zone off the coast of Sumatra, Indonesia. The list of really large earthquakes in the previous paragraph brings up another interesting point. Five earthquakes of magnitude 9 or above have been recorded during the past 45 years, which averages out to one every decade. It turns out that earthquake occurrences seem to follow what is called a power-law distribution, meaning that if there is on average on magnitude 9 earthquake every ten years somewhere in the world, then on average there should be one magnitude 8 earthquake every year, 10 magnitude 7 earthquakes every year, and 100 magnitude 6 earthquakes every year. So, if someone "predicts" that a magnitude 6 earthquake will occur somewhere in the world during the next week, don't be too impressed if it happens because random probability tells us that there should be a magnitude 6 earthquake somewhere in the world every 365/100 = 3.65 days! In reality, things are a little more complicated. But, you get the picture. What did people do before the Richter scale was invented? To some degree, one of the same things that we do today. They observed the intensity or effects of an earthquake at different locations. Whereas the magnitude of an earthquake is a single number regardless of where it's felt, intensity will vary from place to place. In general, the intensity will be much greater near the epicenter than at large distances from the epicenter. This decrease in intensity with distance is known as attenuation. Imagine it this way: If I drop a rock into a pool of water, the difference between magnitude and intensity is similar to the difference between the height of the splash exactly where I drop the rock and the height of the waves all over the pool. Earthquake intensity is most often measured using the modified Mercalli scale, which was invented by the Italian geologist Giuseppi Mercalli in 1902 and uses Roman numerals from I to XII. In the United States, we use the modified Mercalli scale, which was adjusted to account for differences in buildings between Italy and southern California. An earthquake intensity of I is generally not felt, and an intensity of XII represents total destruction of buildings. Some kinds of geologic deposits, most notably water saturated muds, amplify seismic waves and may produce intensities much greater than those for nearby areas underlain by bedrock. Thus, after an earthquake seismologists can interview people and make maps showing the intensity of an earthquake in different areas to better understand the influence of rock or soil type on seismic waves.
Where can actinium be found?
Actinium was discovered in residues from the uranium and radium extraction from ores. The concentration of Ac is extremely low. But actinium can be prepared and artificially, as a result of nuclear reactions. Andre Louis Debierne (France) discovered actinium in 1899. Friedrich Oskar Giesel (Germany) independently discovered it in 1902 but Debierne is largely credited with the discovery.
What type of stress did the 1902 san francisco earthquake have?
The great San Francisco earthquake happened in 1906 and not in 1902. The type of stress was a strike-slip stress.
When was Francisco Rebolo born?
Francisco Rebolo was born in 1902.
When was Francisco Galán born?
Francisco Galán was born in 1902.
What famous photographer was born in San Francisco in 1902?
Ansel Adams was born in San Francisco on February 20, 1902.
When was Francisco Jambrina born?
Francisco Jambrina was born in 1902, in Spain.
What are the release dates for Bird's-Eye View of San Francisco Cal- from a Balloon - 1902?
Bird's-Eye View of San Francisco Cal- from a Balloon - 1902 was released on: USA: January 1902
What is the oldest hotel in San Francisco?
Hotel Majestic. One of the few to survive the 1906 earthquake, built in 1902. However, there are several hotels in older buildings, though they became hotels for recently.
When was Hotel Majestic - San Francisco - created?
Hotel Majestic - San Francisco - was created in 1902.
When was Francisco Martínez Soria born?
Francisco Martínez Soria was born on 1902-12-18.
When was Francisco Petrone born?
Francisco Petrone was born on August 14, 1902, in Buenos Aires, Argentina.
When did Francisco Javier de Burgos y Sarragoiti die?
Francisco Javier de Burgos y Sarragoiti died in 1902.
How many 1902 dimes were minted?
Mintage of 1902 Barber dimes: Proof 777/ Philadelphia 21,380,000/ New Orleans 4,500,000/ San Francisco 2,070,000
