Invariable Track Down of Earth Motion - Kuwait National Seismic Network
Sunday, December 1, 2013
Creation is never complete without challenges, be it our nature, plants, animals or human beings. Moreover, challenges create stress which in turn results in creating adverse or tough circumstances. It is natural that the accumulated energy has to be released to attain a stable state. In such a circumstance, an emotional outburst can be identified with human beings. But, when it comes to the earth we live in, this sudden outburst of energy due to the stress, mostly caused by the plate tectonics, are resulting in earthquakes. The released energy waves named as ‘seismic waves’ cause various effects ranging from minor shaking to larger catastrophes like vast damage to structures, flood, tsunami, landslides and fire outbreaks.
Efforts to record the magnitude of earthquakes resulted in the first seismograph invented by Chinese astronomer Chang Heng in 132A.D. It was designed with eight dragons in eight different directions of the seismograph, holding a ball in its mouth. The jerking due to the earthquake will allow the ball to fall, making noise to alert the watch-guard and the dragon with empty mouth will give the direction of the earthquake. After undergoing drastic up-gradations, now we have electronic seismographs which are competent enough to provide us the whole story of even a petite vibration underneath.
There is no past records of major earthquakes in Kuwait. Though the regional centers detected many moderate earthquakes, it was in 1931 the international network detected one in Kuwait with a magnitude of 4.8, for the first time. Years later, in 1994, Kuwait Council of Ministers insisted to have a national monitoring system. According to their guidelines Kuwait Institute for Scientific Research (KISR) established Kuwait National Seismic Network (KNSN) in 1996 which started functioning in March 1997. Designed and equipped with most modern techniques of international standard, KNSN proves to be one of the most efficient network.
The network consists of eight permanent and six portable seismic monitoring stations spread all over Kuwait according to the tectonic conditions. Seismometers are placed in a four meters deep cylindrical room made in the ground. They are placed on a leveled surface in such a way that its position does not change with any external force. The signals are recorded and digitalized using refraction technology data acquisition system (DAS). Seismometers placed at each station converts the earth’s vibrations into electrical pulses proportional to the amplitude of these vibrations. It is then transmitted to KISR through transmitter-receiver system fixed on a communication tower erected at each station. Interestingly the stations are powered by batteries which are charged through solar cells for a consistent power supply. The data is continuously recorded and analysed on 24 x 7 basis. When an abnormal seismic wave is observed, the data is picked and plotted automatically. Being a real-time seismic network, the center holds GPS Receiver/Clock for accurate Universal Time. This setup enables KNSN to record all local, regional and distant seismic events. The data is used to figure out the seismicity and the potential seismic hazard in Kuwait and the adjacent zone.
More than 300 ‘medium magnitude’ earthquakes are recorded by KNSN among which the major one felt by the people was that occurred in Minagish area in 1997, 4.3 in magnitude scale. Recorded data were used to formulate the earthquake activity in Kuwait. The major areas of concern are Minagish – Umm Gudair oil fields in the south and Al Raudhatain - Al Sabiryiah oil fields in the north, magnitude less than 4.5 and at a depth less than 30 km. Experts says that some of these earthquakes can be attributed to the oil production activity there and others occurred as a result of the relative tectonic movement between Arabian and adjacent plates.
The vibrations of the Earth travel through different layers to reach the observatories, with different velocity and magnitude. The sensitive seismometer records it and the experts analyses them to find its origin and magnitude. The seismometers engaged in KNSN are exceptionally sensitive in capturing the ground motion that it sends a signal even at a strong foot stamp near it, of course not a seismic one. Seismic waves resembling earthquake can be caused even by man-made explosions as in the case of breaking rocks underneath for the construction of roads, rails, subways etc which can be felt by people and thereby leading to a false report testimony. Here arises the vital role of the expertise of a seismologist who reads the plotted data of abnormal signals. KNSN is equipped with most modern facilities and experienced seismologists to deliver a precise and reliable seismic reports and further research.
s
Reshmy Krishnakumar is a freelance Statistician based in India. She was working with Kuwait Institute for Scientific Research (KISR) as Research Associate. Having done her post-graduation in Statistics, she worked as lecturer at St.Teresa’s College, Ernakulam, until her relocation to Kuwait to join at Statistics Department, Kuwait University, Khaldiya.
As a freelance writer, she is contributing to various magazines, blogs, and websites. Her passion includes classical dance, writing poems in Malayalam and Hindi. While in Kuwait she was an active member of the Writers’ Forum Kuwait, Indian Women In Kuwait (IWIK) and Science International Forum (SIF) Kuwait.
View full profile