Power is called exogenous and endogenous, whatcausesearthquakes.com exogenous are workers who come from outside the Earth . This effort to use water, wind, and glaciers to change and shape the earth’s surface. Exogenous force is divided into two, namely sedimentation and erosion. Sedimentation is the deposition of sediment material , while erosion is the erosion of the surface of the earth
Endogenous power is energy derived from the earth . This power comes from stress due to the heat inside the earth. This force is divided into 3 tektonisme, volcanism, and seisme. Tektonisme is a change in the form of the earth, because of the pressure that presses a layer of earth . while volcanism is magma and volcanic activity . Seisme was an earthquake.
Seisme is the event of the earth’s surface . the earth shook, as a result of volcanic activity, or the process of faults and folds. Fault is the pressure that presses hard earth layer and occur in a short time, so that the surface of the earth be broken . While the crease is the pressure at the Earth’s surface that is softer, and occurs in a slow time, so that the earth becomes wrinkled or folded
Earthquakes are one of the natural disasters that occur on Earth. besides, earthquakes can also occur due to friction between the two straightforward, resulting in vibration . The earthquake that occurred in Aceh on December 7, 2016 yesterday, a result of two straightforward lateral friction along the fault. This causes the earth to vibrate. Earthquakes can occur only once or repeatedly. Earthquakes can occur on land and at sea. A strong earthquake occurred in the sea, has the potential to cause a tsunami.
An earthquake is a vibration, resulting in waves. Earthquake waves are divided into two, namely hiposentrum and epicenter
- Hiposentrum is epicentres. The closer to the location hiposentrum, the earthquake will be felt. Hiposentrum are in the earth. hiposentrum an elastic wave that is in the earth.
- Epicenter is a medium that transmit vibrations or waves issued by the epicenter. The farther away from hiposentrum, the epicenter would be lower. The epicenter of the coming of the wave propagation results hiposentrum, and were in the earth’s surface.
Seisme unpredictable occurrence. But the power of vibration as well as the location of hiposentrum predictable tool wear called seismometers. Seismometer is an earthquake vibration measuring device, and is used to view the strength of the earthquake that occurred.
Earthquakes are one of the natural disasters that can not be predicted when it would happen. however, through a tool, can be measured vibration strength and location of hiposentrum. The tool is called seismometer. Seismometer is a device for measuring the vibration of the ground, to find the source of the earthquake, the depth of the earthquake, as well as the strength of the earthquake. Seismometers are devices that are very sensitive to movement up and down the surface of the earth. any movement in the earth is able to vibrate the earth.
seismometer when first created, using optical device or a mechanical linkage to balance vibration, and record it in the paper. Will the modern era like now, seismometer wearing electrical devices. Where electro meagnetik used as a tool to measure, and record it in digital form. A noted earthquake usually wear 3 measuring equipment for measuring the vibration of the earth.
Three such measuring instruments for measuring vibration from any direction. 3 The measuring instrument is north – south (y axis), east – west (x-axis) and vertical (z-axis). If a scientist only uses one measure, the movement in the form of vertical movement. While the type of horizontal movement in all directions, therefore wear at least 2 measuring instrument.
How it Works seismometer
To measure the horizontal vibration, requires a horizontal pendulum. Horozontal Pendulum is a pendulum that moves kenan and left to measure the vibrations of an earthquake. under emergency pendulum, there are a pen to record the results of measurement of these seismometers. However, this simple seismometer tool is not able to measure low-frequency vibrations have.
So it can not measure and record vibrations which are vibrations of an earthquake with a low scale. Therefore, a simple seismometer is modified by using the inverted pendulum. Inverted pendulum is a pendulum which is mounted on a spring. When there is vibration, the spring will dampen vibration, so the pendulum can measure vibrations with frequencies small.
To measure vertical movement, it takes bebam. In addition spring, and the needle will be showing scale. The principle works are hung on a spring load, with the other spring side hung elsewhere. When there is vertical vibrations, the spring will be elongated and shortened. When spring extends and retracts, the function of the load is to maintain the spring in a state of inertia.
Inertia is due to the spring moving. spring will move up and down according to the vibration in feel. When the spring moves up and down, the needle on a seismometer tool will move, and indicate on a scale that has been prepared.
The more advanced the technology, seismometer undergone many changes. Digital seismometers used today, capable of measuring vibration frequencies up will not be able to be felt by humans. In addition, modern seismometers, able to record at the same horizontal and vertical vibrations. So it does not need two seismometers to measure the two vibration in the earth.
On a scale of seismometer
Seismometers as measuring instruments, require scale in large measure vibration levels and resulting from the earthquake. In the world, there are two scale that until now was used as a reference by scientists to measure the vibrations in the earth. The scale is the Richter scale and Mercalli scale.
Richter scale is a scale that is used for a large measure of vibration generated by the Earth. making table scale, Dikai system of logarithms. So that there is a difference of 10 times larger, the scale of the scale that are in it. Richter scale is also commonly referred to as the open Richter scale. Form scales of magnitude are:
- 1-3: Vibration is not felt
- 3 to 3.9: Starting to feel, but just around the epicenter
- 4 to 4.9: The tremors were felt outside the epicenter, the window began to tremble
- 5 to 5.9: Humans began to stand up and begin to break glass
- 6 to 6.9: Stone, tall buildings, and buildings collapsed weak start
- 7 to 7.9: Landslides and ground begins to crack
- 8 – …: Causes damage to fatal within a hundred meters from the epicenter.
Mercalli scale is a scale used to measure the intensity of the vibration. In addition, mircelli scale used to measure the effect of the earthquake on people, animals, buildings and roads around it. On a scale mircelli, wearing a roman numeral as the measuring scale. This scale does not use algorithms, this scale just look at the impact generated. The shape of the Mercalli scale is:
- I. Can only be felt by seismometers
- II. D only felt around the epicenter
- III. Began to be felt by some people
- IV. Began to be felt a lot of people, the furniture began to shatter, the glass began to shatter
- V. beast starts to fear, the building began to sway
- VI. Objects begin to fall
- VII. The walls began to crack
- VIII. The goods have begun to shift
- IX. Masyarakay into a panic, the ground began to landslides
- X. The building began to collapse, the ground begins to crack
- XI. Soil cracks widened
- XII. The building was destroyed.