Presentation on theme: "Earthquake in israel Wen Xu Xiaojing Yang. Israel is situated astride the Jordan Rift Valley the boundary between the Arabian and African tectonic plates."— Presentation transcript:
Israel is situated astride the Jordan Rift Valley the boundary between the Arabian and African tectonic plates slip displacement has developed along the rift at an average rate of about 1 cm/year 6 times earthquakes
First Reference:Bible References to historical earthquakes find in the Bible. The destruction of the cities of Sodom and Gomorrah, situated adjacent to the Dead Sea, in the Rift Valley Joshua led the Children of Israel across the Jordan River In the 13th Century B.C. Another descriptive biblical reference to an earthquake is found in the Book of Kings
King Uzziah earthquake The earthquake occured around 760 B.C., at the time of the prophet Amos Destroyed the Galilee town of Hazor in the fourth century B.C., the prophet Zechariah still referred to it
Third earthquake The historian of the second temple period, Josephus Flavius, described an earthquake claimed that about 10,000 people perished in Judea as a result of collapse of buildings.
Destroy of Beth She'an It was a thriving City at the end of the 4th century Recent excavations uncovered some columns of the Byzantine Colonnaded Street The Al Aqsa mosque on the Temple Mount destroyed twice Jerusalem was damaged Catastrophic earthquakes have continued to occur through the ages in Israel
A catastrophic event took place in 1759, and was recorded in a letter written in Hebrew by a scribe named Joseph Another large earthquake occured in 1927, causing considerable damage to structures, Large cracks developed in the region of the Dead Sea
Physical evidence for the historic occurance of earthquakes in and off coast Israel has been provided by a bathymetric map of the seabed of the Israeli continental slope
Solutions In view of the seismic history of the area, ongoing research is being carried out on geotechnical aspects of earthquake engineering, particularly as related to Israel.
Aims of the Research One of the primary aims of this research is to attempt to define the most potentially dangerous areas, so that steps can be taken to increase safety in these regions.
Methodology a study of site effects at five locations in Israel, with typical soil profiles, has been presented by Frydman (1993) ---Tel Aviv (site T) ---Haifa Bay (site H) ---Ashdod (site A) ---Eilat (site E) ---Beth She'an (site B)
The Location of sites T---Tel Aviv H---Haifa Bay A---Ashdod E---Eilat B---Beth She'an
Earthquake Records Used for Analyses Recording site LabelDateMagnitude Epicentral dist. (km) Max. accn. (g) HaifaHAug. 845.2200.05 Dead SeaDSOct. 874.36.50.02 WhittierWOct. 876.1190.19 Petrolia, Calif.CJune 755.3310.2 TaftTJuly 527.2450.18
Acceleration time histories of chosen earthquakes
Acceleration response spectra of chosen earthquakes (5% damping)
Effect of soil cover thickness on surface acceleration (Eilat site ) T=4H / Vs
Effect of maximum rock acceleration on surface response (Tel-Aviv site)
The Ministry of Housing has initiated a program to investigate the condition of existing buildings, and where necessary, to carry out the appropriate steps for strengthening them, in high risk areas (e.g. Beit She'an). Similary, studies are being made of the seismic stability of structures and embankments (for example in the Dead Sea area). In parallel, steps are being taken in order to advance the seismic safety of new construction; an updated seismic building code has been issued, and research into aseismic building methods continues. Practices