What are the stages of an earthquake?
Earthquakes are divided into five stages. During each stage, a variety of changes occur in the earth. These changes are the geophysical precursors, and they can help scientists predict earthquakes. In order to understand how these precursors arise and how they help predict earthquakes, the five stages of an earthquake must be understood. These five stages arise from the Elastic Rebound Theory. This section will describe each of the five stages of an earthquake. The information in this section was taken from the books by Rikitake [1976], Meyer [1977], Eiby [1980], Bolt [1988], and Bolt [1993].
Stage I of an earthquake is the buildup of elastic strain. As the two sides of a fault move, elastic strain slowly builds up in the rocks, and the rock particles become compressed together.
Stage II is dilatancy and development of cracks. The rocks are now packed as tightly as possible, and the only way the rocks can change shape is to expand and occupy a larger volume. This increase in volume is called dilatancy. The volume increase is caused by the formation of microcracks. As microcracks form, the water that normally fills the pores and cracks in the rocks is forced out, much like when you step on wet beach sand. Air now fills the pores and cracks in the rocks. During this process, the rocks become stronger and can store more elastic strain. This process can be detected on the surface by uplift and tilting of the ground.
Stage III is the influx of water and unstable deformation in the fault zone. During this stage, water is forced back into the pores and cracks in the rocks by the surrounding water pressures, much like when water fills the footprint in the sand. As the water returns, the dilatant rock loses its increased strength. The rocks are already strained beyond their normal capacity, and the rate at which the rocks fall in strength determines the instant of failure. The inflow of water also prevents further generation of microcracks; thus, the rocks stop expanding. In addition, the water in the rocks provides lubrication for the eventual release of the built-up strain.
Stage IV is fault rupture, or the earthquake. Eventually, the rocks can no longer resist the strain. The fault suddenly ruptures, producing an earthquake. When the fault ruptures, the elastic energy stored in the rocks is released as heat and seismic waves. It is these waves that constitute an earthquake.
Stage V is the sudden drop in stress followed by aftershocks. Most of the elastic strain energy is released by the principal earthquake; however, additional smaller ruptures occur, producing aftershocks. The aftershocks release the remaining strain energy, and eventually the strain in the region decreases and stable conditions return.
Essentially, dilation is the expansion of a rock (or rocks). The four primary stages of dilation in regard to an earthquake are as follows: 1. Micro-cracks in a rock 2. Expansion (dilation) of the rock 3. Influx of water 4. Earthquake Source: San Diego State University GEOL 303 Lecture
Japan had Tsunami and an Earthquake Kansas had an earthquake
The earthquake flattened the entire town.There was an earthquake yesterday.It is predicted that an earthquake along the San Andreas fault in the US would be the most devastating in history.
The highest earthquake reading on the Richter scale is 9.5 when an earthquake struck Chilie
The origin of an earthquake is called the hypocenter or focus. This is the point underground where the earthquake rupture begins.
Earthquake than tsunami
It happened too soon. We're making plans to help but we're still in the preliminary stages.
Essentially, dilation is the expansion of a rock (or rocks). The four primary stages of dilation in regard to an earthquake are as follows: 1. Micro-cracks in a rock 2. Expansion (dilation) of the rock 3. Influx of water 4. Earthquake Source: San Diego State University GEOL 303 Lecture
Earthquakes do not happen in stages, or are visibly predictable like hurricanes or tornadoes. For example, we can use radars and weather tools to detect them. Earthquakes on the other hand, don't happen in stages so we can not precisely predict the exact timing of the earthquake. Scientists have other ways to predict earthquakes, even thought they can not predict the precise timing of the quakes. See the question below to see how scientists (seismologists) can predict roughly when and how much damage an earthquake can impose.
An earthquake's Focus is located directly under the Epicenter of an earthquake. The Epicenterof an earthquake is located on the surface of the earthquake.
Japan had Tsunami and an Earthquake Kansas had an earthquake
The 1933 Sanriku earthquake was a major earthquake.
It was a 9.0 level earthquake
No, the Haiti earthquake in 2010 was not the strongest earthquake ever recorded. The strongest earthquake ever recorded was the 1960 Valdivia earthquake in Chile, which had a magnitude of 9.5 on the Richter scale.
yes the Hawkes bay earthquake is the some as the Napier earthquake
It's a smaller (or sometimes larger) earthquake after the main earthquake
its just earthquake