How to measure earthquake

This earthquake probably had a magnitude around 7 or greater and the ground it displaced formed a steep scarp, having the effect of damming the Murray River, which lies on the fault. This formed a large lake until the river began to flow again to the south around the scarp. How do we measure earthquakes?

How to measure earthquake. 1. Introduction. Earthquakes, landslides, mudslides, and other disasters have seriously threatened the lives and property of Chinese residents [1,2,3,4,5]. People living in poverty are often the most vulnerable to the devastating effects of earthquakes [7,8].It is important to prevent and manage the effects of disasters in advance to help reduce the loss of life and property damage [9,10,11,12].

Study with Quizlet and memorize flashcards containing terms like 1.What is the movement along the ground caused by a sudden release of energy when rocks move along a fault?, 2.When elastically deformed rocks suddenly return to their undeformed shape, what is the process?, 3.The location within the earth along a fault where the first motion of an earthquake happens is known as what? and more.

Earthquakes Living Lab: Finding Epicenters and Measuring Magnitudes Activity—Worksheet 1 Finding Epicenters and Measuring Magnitudes Worksheet Objective: To use seismic data and an interactive simulation to triangulate the location and measure the magnitude of an earthquake. Materials: Work in pairs sharing one computer with Internet access.Measurement. Earthquakes can be measured in several ways. The first way is to describe the earthquake's intensity. Intensity is the measure, in terms of degrees, of damage to the surface and the effects on humans. Intensity records only observations of effects on the crust, not actual ground motion or wave amplitudes which can be recorded by ...Events are updated as frequently as every 5 minutes and are available up to 30 days, except for events of magnitude less than 3.0 (retained 3 days) and events of magnitude less than 4.5 (retained 7 days). Labeled quakes are those with a PAGER alert, a measure of the scope and impact of the event. Step 4 — Open the layer in a new map.A seismograph is a device for measuring the movement of the earth, and consists of a ground- motion detection sensor, called a seismometer, coupled with a recording system. Seismographs operate on the principle of inertia. Seismometers used in earthquake studies are highly sensitive to ground movements, so that movements as small as 1/ ...Know what to do to keep yourself and your loved ones safe during an earthquake. In most situations, you can protect yourself if you immediately DROP, COVER, and HOLD ON. Drop. Cover. Hold on. In most situations, you can protect yourself if you immediately: DROP down onto your hands and knees before the earthquake knocks you down. This position ... Center for Research in Astronomy and Astrophysics Geophysics. If you have the intensity, you can use the relationship between intensity and PGA, or you can generate a synthetic seismogram (forward ...And we mapped their data for you. The ground has shifted beneath Nepal’s feet, and space agencies around the globe are rushing to measure it. But they’re not all hopping on airplanes to Kathmandu; many are simply downloading data collected ...

Scientists use seismic waves to measure how big an earthquake is. They use a device called a seismograph to measure the size of the waves. The size of the waves is called the magnitude. To tell the strength of an earthquake scientists use a scale called the Moment Magnitude Scale or MMS (it used to be called the Richter scale). The larger the ...The technology culls data from USGS field station sensors, which measure the intensity of ground shaking. When a station detects an earthquake, computers can calculate station data and predict ...Is the occurrence of earthquakes affected by the eruption of volcanoes? In a listing of earthquakes, what do the different letters after the magnitude mean? What does the Richter scale tell us about energy released by an earthquake? Alaska. How many earthquakes does Alaska experience in 1 year? Do all of Alaska's earthquake occur on mapped ...Each earthquake produces three basic types of seismic waves. Each seismic wave has a different type of motion and travels through the earth at different speeds. Scientists measure seismic waves produced by an earthquake using devices such as a seismograph (or seismometer). A seismograph records ground vibrations.The Chignik earthquake on July 28, 2021, occurred 32 km below the seafloor off the coast of Alaska and, with a magnitude of 8.2, was the seventh strongest earthquake in US history.What to expect during an earthquake. Step 1: Know the Risks and Get Prepared. Before an earthquake. During an earthquake. After an earthquake. Step 2: Make a plan. Step 3: Get an emergency kit. This publication was produced by Public Safety Canada in collaboration with: The Canadian Red Cross, Natural Resources Canada, and the St. John Ambulance.A commonly used earthquake scale is the surface wave magnitude scale, or MS, which measures the largest deflection of the needle on the seismograph for a surface wave that takes about twenty seconds to pass a point (which is about the same frequency as some ocean waves). The magnitude scale most useful to professionals is the moment magnitude ...

Find 23 millimeters on the right side of the chart and mark that point. Place a ruler (or straight edge) on the chart between the points you marked for the distance to the epicenter and the amplitude. The point where your ruler crosses the middle line on the chart marks the magnitude (strength) of the earthquake. An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth, resulting from the sudden release of energy in the Earth’s lithosphere that creates seismic waves. The release of energy occurs along a fault. A …But these underground cables can also have a surprising secondary function: they can sense and measure earthquakes. In a new study at Caltech, scientists report using a section of fiber optic cable to measure intricate details of a magnitude 6 earthquake, pinpointing the time and location of four individual asperities, the "stuck" areas of the ...The first earthquake measuring device was a seismoscope, which was invented in 132 A.D. in China by philosopher Chang Hêng. It was a vase-like instrument with eight dragon heads (each holding bronze ball) lined up in the eight principle directions of a compass with an open-mouthed toad lined up beneath each dragon head (see Figure 1). When an ...Earthquake intensity measures how strongly the earthquake impacts a specific location. In the light bulb analogy, it is the brightness with which you ...

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Earthquake Preparedness. is a Philippine national institution dedicated to provide information on the activities of volcanoes, earthquakes, and tsunamis, as well as other specialized information and …Earthquake size, as measured by the Richter Scale is a well known, but not well understood, concept. The idea of a logarithmic earthquake magnitude scale was first …The second type of body wave is the S wave or secondary wave, and are easy to remember because they’re the second wave to arrive after an earthquake. An S wave is about 1.7 times slower than a P wave. The biggest difference is that S waves can’t move through liquids. Because S waves only move through solids, seismologists were led to ...Measuring Size of Earthquakes The size of an earthquake depends on the size of the fault and the amount of slip on the fault, but that's not something scientists can simply measure with a measuring tape since faults are many kilometers deep beneath the earth's surface. They use

The scale was developed in the 1970s to succeed the 1930s-era Richter magnitude scale (ML). Even though the formulae are different, the new scale retains the familiar continuum of magnitude values defined by the older one. The MMS is now the scale used to estimate magnitudes for all modern large earthquakes by the United States Geological Survey.During an earthquake: Stay calm and stay put. Duck, cover and hold under somewhere stable (ex. desk or table) Stay away from glass windows, shelves, and heavy and hanging objects. Exit the building only once shaking stops via stairs. Elevators are not to be used. Evacuate to an open area away from trees, electric posts and landslide prone …On the Richter scale for measuring earthquake strength, an earthquake with a given reading on the scale is 10 times stronger than an earthquake with a reading of 1 less on the scale. If earthquake A measures 2 on the scale and earthquake B is 1,000 times stronger than earthquake A, how does earthquake B measure on the scale? A. 25 B. 5 C. 7.25 ...For all other earthquakes, the moment magnitude (Mw) scale is a more accurate measure of the earthquake size. Although similar seismographs had existed since the 1890's, it was only in 1935 that Charles F. Richter, a seismologist at the California Institute of Technology, introduced the concept of earthquake magnitude. An earthquake is measured on Richter’s scale. A seismometer detects the vibrations caused by an earthquake. It plots these vibrations on a seismograph. The strength, or magnitude, of an earthquake, is measured using the Richter scale. Quakes measuring around 7 or 8 on the Richter scale can be devastating.Due to the recent earthquakes in Syria and Türkiye, we introduced temporary special measures to support. ... This measure applies to all applications we approve before January 3, 2024. If you can’t include a copy of your passport or travel document with your permanent resident application, include a supporting document …Earthquake - Reducing Hazards: Considerable work has been done in seismology to explain the characteristics of the recorded ground motions in earthquakes. Such knowledge is needed to predict ground motions in future earthquakes so that earthquake-resistant structures can be designed. Although earthquakes cause death and destruction through such secondary effects as landslides, tsunamis, fires ...The Richter scale measures the magnitude of an earthquake (how powerful it is). It is measured using a machine called a seismometer which produces a seismograph. It is logarithmic which means, for example, that an earthquake measuring magnitude 5 is ten times more powerful than an earthquake measuring 4.An earthquake's strength is measured on the Richter scale. The Richter scale goes from 1 to 10. Each increase of 1 on the Richter scale means the earthquake is actually 10 times more powerful (e.g. a 2.0 earthquake is 10 times stronger than a 1.0 earthquake, not twice as strong).Moment magnitude scale: measures the total energy released by an earthquake. Calculated from the area of the fault that is ruptured and the distance the ground moved along the fault. The Richter scale and the moment magnitude scale are logarithmic scales. The amplitude of the largest wave increases ten times from one integer to the next.The Richter scale measures earthquake strength. Volcanoes have a similar scale called the Volcanic Explosivity Index (VEI). The scale was invented by Chris Newhall of the U.S. Geological Survey and Stephen Self of the University of Hawaii in 1982. The Volcanic Explosivity Index gives us a way to measure the relative explosiveness of volcanic ...On the Richter scale, the Alaska quake was "bigger" having a M S of 8.6 compared to the M S of the Chilean quake of 8.5. However, in measuring the seismic moment, the Chilean quake was larger, giving M w of 9.5 versus the M w of 9.2 for the Alaskan earthquake. The reason is that the Chilean earthquake released more energy, but in the Alaskan ...

People feel approximately 1 million earthquakes a year, usually when they are close to the source and the earthquake registers at least moment magnitude 2.5. Major earthquakes of moment magnitude 7.0 and higher are extremely rare. The U. S. Geological Survey (USGS) Earthquakes Hazards Program real-time map shows the location and magnitude of ...

A seismometer is an instrument that responds to ground noises and shaking such as caused by quakes, volcanic eruptions, and explosions.They are usually combined with a timing device and a recording device to form a seismograph. The output of such a device—formerly recorded on paper (see picture) or film, now recorded and processed …a. Earthquake magnitude is the measure of the size of the seismic waves that are produced by an earthquake. b. A number scale system is used to determine the magnitude of an earthquake in the Richter scale. Using this scale, the amplitude of earthquakes can be compared. c.Geologists use seismic waves to locate the epicenter of an earthquake. earthquake. the shaking that results from the sudden movement of rock along a fault. focus. the area beneath Earth's surface where rock that is under stress breaks, triggering an earthquake. epicenter. the point on the surface directly above the focus.To locate an earthquake epicenter: 1. Scientists first determine the epicenter distance from three different seismographs. The longer the time between the arrival of the P-wave and S-wave, the farther away is the epicenter. So the difference in the P and S wave arrival times determines the distance between the epicenter and a seismometer.Earthquake, any sudden shaking of the ground caused by the passage of seismic waves through Earth’s rocks. Earthquakes occur most often along geologic faults, narrow zones where rock masses move in relation to one another. Learn more about the causes and effects of earthquakes in this article.The Intensity 7 ( 震度7, Shindo 7) is the maximum intensity in the Japan Meteorological Agency seismic intensity scale, covering earthquakes with an instrumental intensity (計測震度) of 6.5 and up. [15] At Intensity 7, it becomes impossible to move at will. [13] The intensity was made in the wake of the 1948 Fukui earthquake.17-May-2012 ... The science of seismology is based on the idea of using a sensor to detect an earthquake and to measure its magnitude. Seismology also focuses ...Measurement. Earthquakes can be measured in several ways. The first way is to describe the earthquake's intensity. Intensity is the measure, in terms of degrees, of damage to the surface and the effects on humans. Intensity records only observations of effects on the crust, not actual ground motion or wave amplitudes which can be recorded by ... An earthquake is what happens when two blocks of the earth suddenly slip past one another. The surface where they slip is called the fault or fault plane. The location below the earth’s surface where the earthquake starts is called the hypocenter, and the location directly above it on the surface of the earth is called the epicenter. In particular, for very large earthquakes, moment magnitude gives the most reliable estimate of earthquake size. How do scientists measure the intensity of an earthquake? A seismograph is the primary earthquake measuring instrument. The seismograph produces a digital graphic recording of the ground motion caused by the seismic waves.

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Earthquake Dimensions - Rupture Size and Offset. Another measure of earthquake size is the area of the fault that slipped during the earthquake. During large earthquakes the part of the fault that ruptures may be hundreds of kilometers long and 10s of kilometers deep. Smaller earthquake rupture smaller portions of the fault.earthquake and this voltage is then transmitted to a computer display. • The strength or size of an earthquake is called it [s magnitude. The bigger the earthquake, the more energy released and the bigger the earthquake [s magnitude. An earthquake with a large magnitude will make the Earth [s surface shake more andDamage and Shaking. Seismologists study earthquakes by looking at the damage that was caused and by using seismometers. A seismometer is an instrument that records the shaking of the Earth's surface caused by seismic waves. The term seismograph usually refers to the combined seismometer and recording device.Charles Richter and Beno Gutenberg developed a new magnitude scale for earthquakes, now known as the Richter Scale. 1936 – P-waves measure inner core. Inge Lehmann used data from P-waves to suggest the existence of an inner core to the Earth. 1961 – Monitoring earthquakes worldwide. A worldwide earthquake monitoring system was set up.Geologists use seismic waves to locate the epicenter of an earthquake. earthquake. the shaking that results from the sudden movement of rock along a fault. focus. the area beneath Earth's surface where rock that is under stress breaks, triggering an earthquake. epicenter. the point on the surface directly above the focus.Find 23 millimeters on the right side of the chart and mark that point. Place a ruler (or straight edge) on the chart between the points you marked for the distance to the epicenter and the amplitude. The point where your ruler crosses the middle line on the chart marks the magnitude (strength) of the earthquake. To measure the magnitude of an earthquake, the American scientist Charles Richter developed a scale in 1935. Known as the Richter scale, it assigns a number based on the height of the waves on a seismogram (the visual output of a seismograph). Seismographs measure ground motion, including the energy released by an earthquake. ...Two scales are used commonly to measure earthquake strength. You can measure an earthquake either by its size where the rock slipped, or by the amount of shaking that is experienced at a place that interests you. Both measures are used. The measure of the size of the earthquake where it occurred is the “magnitude.”.Oct 22, 2023 · There are two ways by which we can measure the strength of an earthquake: magnitude and intensity. Magnitude is proportional to the energy released by an earthquake at the focus. It is calculated from earthquakes recorded by an instrument called seismograph. It is represented by Arabic Numbers (e.g. 4.8, 9.0). ….

It measures the energy released during an earthquake by analyzing the amplitude of seismic waves recorded on seismographs. The Richter scale is logarithmic, meaning that each whole number increase on the scale corresponds to a tenfold increase in the amplitude of the seismic waves and approximately 31.6 times more energy released.3m ago. Major League Soccer introduced a temporary measure last week prohibiting fans attending matches from bringing signs, banners, flags or Tifos that …Seismic Monitor - Recent earthquakes on a world map and much more. Latitude: 90 N. Longitude: 203 W. Help Earthquake headlines Last 30 Days Earthquakes Special Quakes Plate Tectonics Education Links IEB. Up-to-date map of the latest earthquakes with resources like news, lists, tools and a 3D viewer.Dr Elizabeth Cochran, a geophysicist with the United States Geological Survey (USGS), says the technology could potentially be applied to earthquake early warning systems, once refined. Such ...1. Introduce the topic of earthquake measurement. Today, we will learn one method used to measure earthquakes. An earthquake's magnitude is a measurement of the amount of energy released by an earthquake. A seismograph is an instrument used to record the motion of earthquake waves. 2. Show students the 'Seismographs' transparency.Earthquake size, as measured by the Richter Scale is a well known, but not well understood, concept. The idea of a logarithmic earthquake magnitude scale was first …Engineers often invent scales or systems to use as measurement tools. For example, the Richter scale is an invented mathematical (logarithmic) tool that measures the magnitude of an earthquake. By using a common rating scale, engineers can compare earthquake activity measured from everywhere on Earth. Analyzing the amount of energy released by ...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.Measuring earthquakes. Seismometers are the instruments that are used to measure the motion of the ground, which includes those seismic waves generated by earthquakes, volcanic eruptions, and other seismic sources. A Seismograph is also another term used to mean seismometer though it is more applicable to older instruments.The Richter magnitude scale is used to measure the strength or magnitude of an earthquake. It is the most commonly used scale and assigns a number between 1 and 10 based on the amount of energy released by the earthquake. The larger the magnitude, the greater the intensity of the earthquake. About. How to measure earthquake, Earthquakes are measured using seismographs, which monitor the seismic waves that travel through the Earth after an earthquake strikes. Scientists used the Richter Scale for many years but now ..., Though earthquakes have terrorized people since ancient times, it's only been in the past 100 years that scientists have come to understand what causes them, and to develop technology to detect their origin and measure their magnitude. In addition, engineers and architects have worked to make buildings more resistant to earthquake shocks., For example, an earthquake measuring 4.0 on the Richter Scale has ten times the magnitude of a 3.0 earthquake. And so it goes, point by point, across the whole scale. The Richter scale is not additive, but logarithmic. Charles Richter s scale relates to shaking experienced at the surface. The scale also relates to the energy needed to cause ..., Use the Earthquake Catalog Search to find earthquakes within a certain distance of any location. Expand "Advanced Options" and fill in the "Circle" fields. Search Earthquake Catalog. *United States earthquake lists (except "Top...") also include some earthquakes outside the U.S. since the search area is a rectangle., earthquake: a sudden rapid shaking of the ground caused by a rapid release of energy epicenter: the point on the Earth's surface that is vertically above the focus of an earthquake. fault: a break or fracture in a rock mass across which movement has occurred. focus (hypocenter): the point of origin of an earthquake. seismograph: any of various instruments for measuring and recording the ..., Earthquakes can be caused by movement within the earth's crust, volcanic eruption, or artificial reasons. In Geography Class 11: Earthquake notes, we will study the type of earthquake waves, the propagation of the earthquake waves, the different types of earthquakes, and how to measure earthquakes. Effects of Earthquakes, We use exaggerated motion of a building (seismic station) to show how the ground moves during an earthquake, and why it is important to measure seismic waves using 3 components: vertical, N-S, and E-W. Before showing an actual distant earthquake, we break down the three axes of movement to clarify the 3 seismograms., An interesting web site on earthquakes is the USGS Earthquake Information site. In particular, this site has a map of the recent earthquakes in California. The following table gives the released energies of earthquakes of magitudes 1 up to 9 in increments of 0.5. This table illustrates the exponential growth of the power of an earthquake., In the article below, you'll learn about the different measures of an earthquake: from the famous Richter scale to the currently used moment magnitude scale and Mercalli scale, which is an intensity scale describing the effects of the phenomenon.Play with the tool to contemplate and admire Mother Earth's natural strength, or scroll down to …, Jun 22, 2023 · Sometimes, earthquakes at or below a magnitude of 3.5 will still use the Richter Scale for taking measurements. The Richter Scale is an otherwise outdated measurement system due to its inability to measure very large earthquakes. In addition to measuring an earthquake’s magnitude, we can also measure its intensity. , Measuring the size of an earthquake. Earthquakes range broadly in size. A rock-burst in an Idaho silver mine may involve the fracture of 1 meter of rock; the 1965 Rat Island earthquake in the Aleutian arc involved a 650-kilometer length of the Earth's crust. Earthquakes can be even smaller and even larger., Measuring the intensity. In many ways, the intensity is an even more important measure of an earthquake as it is related to the tangible impact a quake has. Intensity scales, like the Modified Mercalli Scale and the Rossi-Forel scale, measure the amount of shaking at a particular location., The measure of the size of the earthquake where it occurred is the "magnitude." Each earthquake has a single value on a magnitude scale - the strength right in the body of rock that sprang to a new position or broke. The magnitude scale is logarithmic - an earthquake of magnitude 2 is 30 times as large as one of magnitude 1, and an ..., The Moment Magnitude Scale. The Richter scale was originally designed to measure medium-sized earthquakes, those between magnitude 3 and 7, and within a distance of about 400 miles. The moment ..., Measuring an earthquake . It is common to associate the severity of an earthquake with its size, or magnitude. A more accurate indicator of damage, however, is the earthquake's intensity at each ..., Earthquakes measuring upwards of 7 are less frequent but very powerful and can cause a lot of destruction. The largest earthquake ever recorded was in Chile in 1960, it measured 9.5 on the Richter ..., Earthquake, any sudden shaking of the ground caused by the passage of seismic waves through Earth’s rocks. Earthquakes occur most often along geologic faults, narrow zones where rock masses move in relation to one another. Learn more about the causes and effects of earthquakes in this article., The Basic Precautionary Measures to Do During an Earthquake “Duck, cover, and hold” is the basic drill taught in schools and workplaces to provide protection to people especially during a strong earthquake. This is the basic way to survive and protect yourself from severe injuries caused by the earthquake. If you are in the road in your ..., Earthquake Dimensions - Rupture Size and Offset. Another measure of earthquake size is the area of the fault that slipped during the earthquake. During large earthquakes the part of the fault that ruptures may be hundreds of kilometers long and 10s of kilometers deep. Smaller earthquake rupture smaller portions of the fault., 08-May-2020 ... Measuring Seismic Waves. Seismic waves are measured on a seismograph. Seismographs contain a lot of information, and not just about earthquakes., Two of the most common methods used to measure earthquakes are the Richter scale and the moment magnitude scale. The Mercalli scale also measures the effects of an earthquake at different locations., The National Earthquake Hazards Reduction Program (NEHRP) leads the federal government’s efforts to reduce the fatalities, injuries and property losses caused by earthquakes. Congress established NEHRP in 1977, directing that four federal agencies coordinate their complementary activities to implement and maintain the program., In an earthquake, damage to buildings and infrastructure is related more closely to ground motion, of which PGA is a measure, rather than the magnitude of the earthquake itself. For moderate earthquakes, PGA is a reasonably good determinant of damage; in severe earthquakes, damage is more often correlated with peak ground velocity. , The Richter scale measures earthquake strength. Volcanoes have a similar scale called the Volcanic Explosivity Index (VEI). The scale was invented by Chris Newhall of the U.S. Geological Survey and Stephen Self of the University of Hawaii in 1982. The Volcanic Explosivity Index gives us a way to measure the relative explosiveness of volcanic ..., Enter the two magnitudes you want to compare – for our example, these are 5.8 and 7.1. We find out that a magnitude of 7.1 is 20 times bigger (on a seismogram, in terms of amplitudes) and ~89 times stronger (in terms of energy release) than a 5.8 magnitude. Remember that for each unit increase in magnitude:, 1. learn about the cause of earthquakes, 2. learn about how scientists measure earthquake intensity, 3. build their own seismograph to measure shaking. Materials . marker or felt-tip pen . plastic or metal ruler that is flexible . tape (masking tape is best) something heavy (a can of soup is perfect!) newspaper or other big scratch paper ..., 3m ago. Major League Soccer introduced a temporary measure last week prohibiting fans attending matches from bringing signs, banners, flags or Tifos that …, 15. Atacama, Chile; 1922; magnitude 8.5. A black and white photograph showing the damage caused by the Vallenar earthquake in 1922. (Image credit: By Gustavo Bruzzone Rocco - Unknown source ..., It is not possible to prevent the occurrence of an earthquake; hence, the next best option is to emphasis on disaster preparedness and mitigation rather than curative measures such as: Establishing earthquake monitoring centres (seismological centres) for regular monitoring and fast dissemination of information among the people., A simple seismometer, sensitive to up-down motions of the Earth, is like a weight hanging from a spring, both suspended from a frame that moves along with any motion detected. The relative motion between the weight (called the mass) and the frame provides a measurement of the vertical ground motion. , The Richter Scale is a quantitative measure of the Earthquake magnitude. It is also called the magnitude scale, where the energy released is measured in the range of 1-10. Richter scale is one of the most important topics for the UPSC IAS exam. It covers a significant part of Geography in the General Studies Paper-1 syllabus and Science and ..., 17-May-2012 ... The science of seismology is based on the idea of using a sensor to detect an earthquake and to measure its magnitude. Seismology also focuses ..., where Mo is seismic moment of the earthquake in dyne cm. The seismic moment is defined as Mo = µA ∆u (7) where µ = shear modulus, A = fault area and ∆u = average slip over the fault area (Aki, 1966). Hence the seismic moment of an earthquake is a direct measure of the strength of an earthquake caused by fault slip.