Перевод на пож what causes earthquakes? 01.1.r o1d earth stretc hes and deforms its rock layers at a rate too fast for themselves quitietly. scientists are not su/e whether the eart his growing bigger and stretching crustàlrocks,orshrinking to wrinkle them like dried appleskins.in any cmse,therearenian#r: asonsforthesqueezingand tw isting ofthe rocks thatcause such trouble. chem icaland radioactivereactionsm elttheinteriorm aterialscausing rocks.m ostim portantm ay be the w eightof eag h m aterialm oved from placeto placeby the ruslting waters of rivers.this happens slow ly,butthere is a11thetimeintheworld,mldafterm illionsofyears theweightof m aterialbecom esvery great. ' breaking takes place along zones of weakness called faults.oneside of the rock m ovespastthe other,sidew aysor up ordown,sliding and grinding along the fault untilthe tension is released. therock then com esto restin itsnew position,to stay untiltension builds up again.the following two exam ples m ay dem onstrate the disaster. 11 on a pril18, 1906,one of the greatest shocks in a m erican history struck san francisco, it 150 happened at 5: 12 on a weekday m orning w hen the downtow n business districtw as deserted and streets were empty.the death tollwas between 452 and 498 persons. a ctually the quake buckled and rolled over a 200-m i1e stretch of the san a ndreas fault. altogether,âtleast 700 persons were killed. rqnfrancisco'sdnmagewasestimatedat$400million ata tim eofs-centbeerand ls-centprim ebeef. w hat if a quake of sim ilar strength struck at noon on a week-day? itis a chilling possibility. can citieseventually bebuiltso they're quakeproof? yes,say the experts. studied during thepasthalfcentury. rthere is no reason for a fifty-storey building to be less safe than a five-storey building if it is constructed properlyy''saysdr.george w .h ousner,caltech .finally, willit eventually be possible to predict quakes? an internationalstudy is now in progress in an effort to answer this question. gw ith increasing inform ation about the eazth m ovem ents a1lover the world,''dr.benioff says, d w ould tellus when and where the breaking point hasbeen reached-'' it can't be concluded as yet that earthqultktls com ein cyclesbecausethey haven'tbeen observtltl orrecorded long enough.iii r 3. the possibility ofconstructing quake-proof < 'the likelihood of a major er thquake hitting ' ,, a. itj gapanese ' 4' pho possibility to forecastearthquakes. tokyo is now greater than ever, s geographer takam asa nakuno.on average severe ' r , . - 3aaaxee 9.l'ipoql/'ral're iï rzepecltam hq'e earthquakes(aboutviiion themodified mercali scaleor6.5ontherichterscale)alfectthetokyo torct' areaabout10timesacentury.thelastcomparable oneofm; . quake wasin 1929,sothenextisreckoned tobe ,strdch. welloverdue.the last destructive earthquake to ing from towardslake affect tokyo occurred in 1923 when 60,000 lives eyre,is wellknown to south a ustralians,w ho cart wereclaim ed and 370,000 housesweredestroyed. easilygettherein aday'sdrivefrom adelaide. tokyo has changed considerably since 1923. y itislessvisited bytravellersfrom otherstates the urban area has expanded and the density of butiam pleased to seetravelwritersr on and viv wooden houses has increased. nakuno sees new m oon have written a book on this area. danger areas in the subways and underground ' the flinders ss a long range,stretching from j shopping com plexes. the to the arid the tokyo m etropolitan governm ent stillsees plalnsofm ounth opeless.and ithasbeen around fireasthem ajorhazard resulting from an earth- a long time.its geolo-gy reveals nearly half the quake and its counter-m easures are designed to history ofour planet. dealwith a largenumberofsim ultaneousfireson m ysteriouscarvingsin therocksrevealhum an intlependent sites.a centralpart of their earth- habitation ofat least 15,000 years, quakespolicy istodesignateopen spacesforevacu- thefirsteuropean toseetherangeswasm atthew ation and build fire-proofhighrise buildings.
