Tsunami is a Japanese word which means harbor wave and is used as the scientific term for seismic sea wave generated by an undersea earthquake or possibly an undersea landslide or volcanic eruption. When the ocean floor is tilted or offset during an earthquake, a set of waves is created similar to the concentric waves generated by an object dropped into the wave. Most tsunamis originate along the Ring of Fire, a zone of volcanoes and seismic activity, 32.500 km long that encircles the Pacific Ocean. Since 1819, about 40 tsunami have struck the Hawaiian Islands.

A tsunami can have wave lengths, or widths, of 100 to 200 km, and may travel hundreds of kilometres across the deep ocean, reaching speeds of about 725 to 800 kilometres an hour. Upon entering shallow coastal waters, the wave, which may have been only about half a metre high out at sea, suddenly grows rapidly. When the wave reaches the shore, it may be 15 metres high or more. Tsunamis have tremendous energy because of the great volume of water affected. They are capable of obliterating coastal settlements.

Tsunami should not be confused with storm surges, which are domes of water that rise underneath hurricanes or cyclones and cause extensive coastal flooding when the storms reach land. Storm surges are particularly devastating if they occur at high tide. A cyclone and accompanying storm surge killed an estimated 500,000 people in Bangladesh in 1970. The tsunami which truck south and southeast Asia in late 2004 killed over 200 thousand people.

How are tsunami capable of obliterating coastal settlements?

Câu hỏi liên quan

• The word "them" in the passage 2 refers to_________.

• What were "steady sellers"?

• What might be the most suitable title for this reading passage?

ZUNIA12

• With what topic does this passage primarily deal?

• When did the the Pilgrims make a difficult trip to across the ocean from England?

• The phrase “infringing upon” in paragraph 4 is closest in meaning to _____

• Of the animals with backbones, the first to appear were ______

• Sixty years ago, most women ____________.

• The word “astonished” in paragraph 4 can be best replaced by__________.

• What can be inferred about babies from this passage?

• The word "them" refers to __________

• What is the most likely subject of the paragraph following this passage?

• In what year did Melville’s book about his experiences as a cabin boy appear?

• The word "assigned" in the fourth paragraph mostly means ......

• Most people are afraid of being operated on ............

• The word “ball” in paragraph 2 probably means ............

• What does the passage mainly discuss?

• What can be inferred about machines that are not calculators or computers?

• The word “intermittently” in line 4 is closest in meaning to .........

• The Beatles stopped their live performances because __________