The Sumatra-Andaman arc is an active subduction zone and had generated several destructive Tsunamis in the past.In this paper we have analyzed two historical Tsunamigenic earthquakes from this region. One of the histo...The Sumatra-Andaman arc is an active subduction zone and had generated several destructive Tsunamis in the past.In this paper we have analyzed two historical Tsunamigenic earthquakes from this region. One of the historical earthquake is the earthquake of 26th June 1941 in the North Andaman region,which was one of the strongest in the Andaman Sea and Bay of Bengal of magnitude M_w=7.7.This earthquake had triggered tsunami which affected the east coast of India.The other is the earthquake in Car Nicobar region on 31 st December 1881 of magnitude M_w=7.9. This submarine earthquake beneath the展开更多
Tsunami induced by earthquake is an interaction problem between liquid and solid.Shallow-water wave equation is often used to modeling the tsunami,and the boundary or initial condition of the problem is determined by ...Tsunami induced by earthquake is an interaction problem between liquid and solid.Shallow-water wave equation is often used to modeling the tsunami,and the boundary or initial condition of the problem is determined by the displacement or velocity field from the earthquake under sea floor,usually no interaction between them is consid-ered in pure liquid model.In this study,the potential flow theory and the finite element method with the interaction between liquid and solid are employed to model the dynamic processes of the earthquake and tsunami.For model-ing the earthquake,firstly the initial stress field to generate the earthquake is set up,and then the occurrence of the earthquake is simulated by suddenly reducing the elastic material parameters inside the earthquake fault.It is dif-ferent from seismic dislocation theory in which the relative slip on the fault is specified in advance.The modeling results reveal that P,SP and the surface wave can be found at the sea surface besides the tsunami wave.The surface wave arrives at the distance of 600 km from the epicenter earlier than the tsunami 48 minutes,and its maximum amplitude is 0.55 m,which is 2 times as large as that of the sea floor.Tsunami warning information can be taken from the surface wave on the sea surface,which is much earlier than that obtained from the seismograph stations on land.The tsunami speed on the open sea with 3 km depth is 175.8 m/s,which is a little greater than that pre-dicted by long wave theory,(gh)1/2=171.5 m,and its wavelength and amplitude in average are 32 km and 2 m,respectively.After the tsunami propagates to the continental shelf,its speed and wavelength is reduced,but its amplitude become greater,especially,it can elevate up to 10 m and run 55 m forward in vertical and horizontal directions at sea shore,respectively.The maximum vertical accelerations at the epicenter on the sea surface and on the earthquake fault are 5.9 m/s2 and 16.5 m/s2,respectively,the later is 2.8 times the former,and therefore,sea water is a good shock absorber.The acceleration at the sea shore is about 1/10 as large as at the epicenter.The maximum vertical velocity at the epicenter is 1.4 times that on the fault.The maximum vertical displacement at the fault is less than that at the epicenter.The difference between them is the amplitude of the tsunami at the epicenter.The time of the maximum displacement to occur on the fault is not at the beginning of the fault slipping but retards 23 s.展开更多
Using geoisostasy phenomena,the author has got the answers for some questions about tsunami physical nature.Equilibrium state conception of the rotated Earth as the planet(geoisostasy)was shown on theⅩⅩⅧsession of ...Using geoisostasy phenomena,the author has got the answers for some questions about tsunami physical nature.Equilibrium state conception of the rotated Earth as the planet(geoisostasy)was shown on theⅩⅩⅧsession of the International Geological Congress for the first time.According to geoisostasy conception there are some conditions that must fulfill tsunami development:(1)ocean-floor tectonic motions must have significant vertical components;(2) vertical displacements of tectonic blocks must展开更多
On December 26,2004,the Indian Ocean tsunami waves hit Sri Lanka resulting in the devastation of the coastal aquifers from saltwater contamination.In an attempt to speed up the cleaning process of the contaminated wat...On December 26,2004,the Indian Ocean tsunami waves hit Sri Lanka resulting in the devastation of the coastal aquifers from saltwater contamination.In an attempt to speed up the cleaning process of the contaminated water in wells,large-scale and intensive campaigns went into cleaning and rehabilitating wells through pumping out saline water(physical cleansing). However,it was unclear whether these attempts improved the well-water quality,especially in terms of salinity due to density driven flow and solute transport phenomenon.Changes in water quality of a sand aquifer on the east coast of Sri Lanka owing to the December 26,2004 tsunami and展开更多
Tsunami flooding in December,2004 contaminated the aquifers in many coastal aquifers in Sri Lanka. Seawater entered the aquifers via direct infiltration during tsunami flooding and later as ponded seawater infiltratio...Tsunami flooding in December,2004 contaminated the aquifers in many coastal aquifers in Sri Lanka. Seawater entered the aquifers via direct infiltration during tsunami flooding and later as ponded seawater infiltration through the permeable sands that are typical of coastal aquifers.Majority of the traditional shallow dug wells that are tapping the tsunami affected coastal aquifers cannot be used for展开更多
文摘The Sumatra-Andaman arc is an active subduction zone and had generated several destructive Tsunamis in the past.In this paper we have analyzed two historical Tsunamigenic earthquakes from this region. One of the historical earthquake is the earthquake of 26th June 1941 in the North Andaman region,which was one of the strongest in the Andaman Sea and Bay of Bengal of magnitude M_w=7.7.This earthquake had triggered tsunami which affected the east coast of India.The other is the earthquake in Car Nicobar region on 31 st December 1881 of magnitude M_w=7.9. This submarine earthquake beneath the
基金National Natural Science Foundation of China (40521002 and 40474013).
文摘Tsunami induced by earthquake is an interaction problem between liquid and solid.Shallow-water wave equation is often used to modeling the tsunami,and the boundary or initial condition of the problem is determined by the displacement or velocity field from the earthquake under sea floor,usually no interaction between them is consid-ered in pure liquid model.In this study,the potential flow theory and the finite element method with the interaction between liquid and solid are employed to model the dynamic processes of the earthquake and tsunami.For model-ing the earthquake,firstly the initial stress field to generate the earthquake is set up,and then the occurrence of the earthquake is simulated by suddenly reducing the elastic material parameters inside the earthquake fault.It is dif-ferent from seismic dislocation theory in which the relative slip on the fault is specified in advance.The modeling results reveal that P,SP and the surface wave can be found at the sea surface besides the tsunami wave.The surface wave arrives at the distance of 600 km from the epicenter earlier than the tsunami 48 minutes,and its maximum amplitude is 0.55 m,which is 2 times as large as that of the sea floor.Tsunami warning information can be taken from the surface wave on the sea surface,which is much earlier than that obtained from the seismograph stations on land.The tsunami speed on the open sea with 3 km depth is 175.8 m/s,which is a little greater than that pre-dicted by long wave theory,(gh)1/2=171.5 m,and its wavelength and amplitude in average are 32 km and 2 m,respectively.After the tsunami propagates to the continental shelf,its speed and wavelength is reduced,but its amplitude become greater,especially,it can elevate up to 10 m and run 55 m forward in vertical and horizontal directions at sea shore,respectively.The maximum vertical accelerations at the epicenter on the sea surface and on the earthquake fault are 5.9 m/s2 and 16.5 m/s2,respectively,the later is 2.8 times the former,and therefore,sea water is a good shock absorber.The acceleration at the sea shore is about 1/10 as large as at the epicenter.The maximum vertical velocity at the epicenter is 1.4 times that on the fault.The maximum vertical displacement at the fault is less than that at the epicenter.The difference between them is the amplitude of the tsunami at the epicenter.The time of the maximum displacement to occur on the fault is not at the beginning of the fault slipping but retards 23 s.
文摘Using geoisostasy phenomena,the author has got the answers for some questions about tsunami physical nature.Equilibrium state conception of the rotated Earth as the planet(geoisostasy)was shown on theⅩⅩⅧsession of the International Geological Congress for the first time.According to geoisostasy conception there are some conditions that must fulfill tsunami development:(1)ocean-floor tectonic motions must have significant vertical components;(2) vertical displacements of tectonic blocks must
文摘On December 26,2004,the Indian Ocean tsunami waves hit Sri Lanka resulting in the devastation of the coastal aquifers from saltwater contamination.In an attempt to speed up the cleaning process of the contaminated water in wells,large-scale and intensive campaigns went into cleaning and rehabilitating wells through pumping out saline water(physical cleansing). However,it was unclear whether these attempts improved the well-water quality,especially in terms of salinity due to density driven flow and solute transport phenomenon.Changes in water quality of a sand aquifer on the east coast of Sri Lanka owing to the December 26,2004 tsunami and
文摘Tsunami flooding in December,2004 contaminated the aquifers in many coastal aquifers in Sri Lanka. Seawater entered the aquifers via direct infiltration during tsunami flooding and later as ponded seawater infiltration through the permeable sands that are typical of coastal aquifers.Majority of the traditional shallow dug wells that are tapping the tsunami affected coastal aquifers cannot be used for
