Table of Contents
What can seismic waves tell us?
Seismologists study shock, or seismic, waves as they travel through the Earth’s interior. Seismic waves tell us that the Earth’s interior consists of a series of concentric shells, with a thin outer crust, a mantle, a liquid outer core, and a solid inner core.
When a fault is expressed at the surface what is it called?
When a fault is expressed at the surface, it is called a. fault scarp. The name of the site where slippage begins and earthquake waves radiate outward is called the. hypocenter.
What causes the change in the speed of seismic waves as it travels through the Earth?
Seismic waves travel fast, on the order of kilometers per second (km/s). Temperature tends to lower the speed of seismic waves and pressure tends to increase the speed. Pressure increases with depth in Earth because the weight of the rocks above gets larger with increasing depth.
How would the seismograms for the two earthquakes compare?
How would the seismograms for the two earthquakes compare? The bigger earthquake would show bigger, more jagged lines on the seismogram and the weaker quake would have shorter lines.
What causes a surface wave?
Wind-driven waves, or surface waves, are created by the friction between wind and surface water. As wind blows across the surface of the ocean or a lake, the continual disturbance creates a wave crest. These types of waves are found globally across the open ocean and along the coast.
Which best explains liquefaction?
Which of the following best describes liquefaction? The transformation of stable soil into loose, liquefied material that is able to rise toward Earth’s surface. Describe how sand volcanoes form.
What is the cause of tsunami?
What causes tsunamis? Most tsunamis are caused by earthquakes on converging tectonic plate boundaries. However, tsunamis can also be caused by landslides, volcanic activity, certain types of weather, and—possibly—near-earth objects (e.g., asteroids, comets) colliding with or exploding above the ocean.
When seismic waves slow down what does it indicate?
Seismic waves move more slowly through a liquid than a solid. Molten areas within the Earth slow down P waves and stop S waves because their shearing motion cannot be transmitted through a liquid. Partially molten areas may slow down the P waves and attenuate or weaken S waves.
What is the velocity of a surface wave?
waves have a typical group velocity of about 3.5 km/s and can be large-amplitude arrivals on all three components of motion (vertical, radial, and transverse) out to 1000 km.
How do geologists use seismographic data?
Geologists use seismographic data to map faults, to monitor changes along faults, and to predict earthquakes. b. Seismographs detect seismic waves and use this data to study the length and depth of the waves. In this way, geologists can determine the location of the fault and mark it as an earthquake risk area.
What factors could affect the accuracy of determining the epicenter of the earthquake?
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.
How does land use and land cover change?
Projections of both land-use and land-cover changes will depend to some degree on rates of population and economic growth. In general, scenarios that assume continued high growth produce more rapid increases in developed areas of all densities and in areas covered by impervious surfaces (paved areas and buildings) by 2050.
From land surface temperature one can roughly predict atmospheric temperature based on many of such works showing relation between land surface and atmospheric temperature. Kawashima et al. (2000) documented a relation between mean air temperature and mean surface temperature.
Where is the highest rate of land change?
Between 1973 and 2000, the Southeast region had the highest rate of change, due to active forest timber harvesting and replanting, while the Southwest region had the lowest rate of change.
What is the projected increase in urban land cover?
Urban land covers are projected to increase in the lower 48 states by 73% to 98% (to between 10% and 12% of land area versus less than 6% in 1997) by 2050, using low versus high growth assumptions, respectively.