Strike slip fault; Aceh earthquake on Wednesday morning, December 7, 2016 (TIL)

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Much devastation that happened this morning in Aceh, especially in the area of Pidie Jaya and surrounding areas. Many people died. Many also were wounded. Many buildings and public facilities are crumbling. Several heritage buildings collapsed. Panic, crying and anxious spread in various places there.

All that caused a natural disaster, ie: the tectonic earthquake magnitude 6.5 on the Richter Scale on Wednesday December 7, 2016. The center of earthquake located at 5.25 N and 96.24 BT or exactly on the ground at a distance of 106 km south-east of Banda Aceh at a depth of 15 Km. Up at 8:12 pm there was an earthquake aftershock 10 times with the greatest strength of 4.8 on the Richter Scale. (link)

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What really happened to the Earth this morning? I think, this is the right time to learn so that tears were flowing not in vain.

Meteorology and Geophysics Agency (BMKG) has presented a report that the earthquake which occurred a kind of shallow earthquakes caused by the activity of local faults. (link)

What is the fault in geological terms?

A fault is a planar fracture or discontinuity in a volume of rock, across which there has been significant displacement as a result of rock mass movement. Large faults within the Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. (source)

Some geologists structure, interpreted fault structure, generally, as the field of fracture is accompanied by the shift. One complete definition of the fault, as quoted by The Journal of Geology, is:

Fault is defined as a field of fracture accompanied by their relative displacement of one block to block other rocks. The distance can shift a few millimeters to tens of kilometers, while the fault plane size ranging from a few centimeters to tens of kilometers. (source)

Generally there are three (3) primary fault groups, ie reverse fault, normal fault and fault horizontally (Strike-slip fault).

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And that happened in Aceh, this morning, according to the Meteorology, Climatology and Geophysics Agency, is strike-slip fault. Fault suspected of earthquake generator, is Samalanga-Sipopok Fault which fault lines directional southwest-northeast. source

So what was a strike-slip fault?

Strike-slip fault (Transcurent fault; Wrench fault), fault that its formation is influenced by the sharpness of compression. The position of forming the main affirmation of this fault is horizontal, the same as the position of the minimum sharpness, while medium sharpness is a vertical position. source

Another explanation:

The fault surface (Strike slip faults) is the fault which is relative movement of horizontal directional follow the direction of the fault. The fault of this type comes from sharpness shear working in the earth's crust. Fault type of "strike slip fault" can be divided into two (2) depending on the nature of the movement. By observing on one side of the fracture plane and with a view towards the opposite plane fault, then if the plane on one side of the move towards the left we refer to as a fault "left-lateral strike-slip fault". If the plane of fault on the other side moving in the right direction, then we call as "right-lateral strike-slip fault". (source)

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Example fault type of "strike slip fault" most famous being the fault "San Andreas" in California with a length of more than 600 km. (source)

This is what happens on earth, in Aceh, this morning. May God help us.

Other post in STEEMIT about the earthquake in Aceh by @safar01, see: link.

Sources:
1; 2 ; 3 ; 4 ; 5 ; 6