4a Group2 Sichuan Earthquake

The Earthquake of Sichuan

Location of Sichuan

Time and Location of Sichuan Earthquake  at

14:28:01.42 12 May 2008



in Sichuan province

Formation of Sichuan Earthquake 

Indian plate extruded with Eurasian plate



energy transferred from the QinghaiTibet Plain toward interior part of China



accumulated energy released rapidly and suddenly in the Sichuan Provinces

Aftershock  After

Sichuan Earthquake, there were happened thousands of aftershock  Some of them were reach Richter Scale about 6  Those strong aftershock also brought huge damage to Sichuan and neighbor region

Reasons for the great destruction  Great

magnitude (Richter Scale: 8)

 Shallow

focus(19 kilometres )

 Poorly-constructed

 High

building

population density (around 180 /km² )

Effects of the earthquake  Landslide,

mudflow and aftershocks  blocking

rivers and roads (disruption of transportation)



many reservoirs, hydropower stations, dams and water locks have been seriously damaged. e.g. Wuyi, Fengshou reservoirs



Crop failure ( According to the ministry of agriculture, 33,300 hectares of farmland, have been damaged )



Heavy casualties



Property Loss



Collapsed buildings and infrastructure

The Lakes ( 堰塞湖 )  The

Lakes refers to lakes formed after earthquakes

 It

is caused by the blockade of river channel or river bed by materials such as rock and soil

唐家山堰塞湖防 缺堤險情 ( 明報 ) 05 月 24 日 星期六 01:40PM This new shows that there is a potential danger of the Lakes to be flooded

汶川大地震，唐家山堰塞湖近日水位不斷上升，加上未來一兩 日可能下大雨，缺堤的風險大大增加、解放軍已到場戒備。 汶川地震在四川災區形成了３３處堰塞湖，嚴重威脅災區７ ０餘萬群眾和抗震救援部隊及搶險人員的安全。水利部抗震 救災前方領導小組組長矯勇稱，當局已從全國抽調１７０餘 位水利工程和水文勘測專家組成９個專家組和１０個水文勘 測小組，緊急趕赴四川地震災區，會同地方１００多名水利 職工，冒險深入唐家山等堰塞湖現場查勘和監測，基本查清 了堰塞湖的幾何尺寸、來蓄水量、地質構成及下游影響範圍 和人口數量等情況，並及時開始了２４小時不間斷監測預警 。

經現場核定，３３處堰塞湖主要集中在北川、 綿竹和什邡等地，分佈在沱江、涪江、岷江和嘉 陵江水系。單個堰塞湖集雨面積範圍在８０至３ ５５０平方公里之間，堰塞體體積達１０至２０ ３７萬立方米，其地質構成多為鬆散堆積土石體 ，壩高１０至１２０米，最大蓄水量達５０萬至 ３億立方米。矯勇表示，目前已進入汛期，且餘 震時有發生，堰塞湖一旦潰決，產生的次生災害 將非常嚴重。水利部及時組織專家對堰塞湖的災 害風險度進行了研判和評估，制定了應急除險、 避險預案，依據輕重緩急和條件，開展了除險減 災工作，已有７處險情解除。

位於北川縣城上游３．２公里處的唐家山堰塞湖是風險度最高最 難處置的堰塞體。該堰塞體長８０３米，寬６１１米，高８２ ．６５米至１２４．４米，方量約２０３７萬立方米，估算最 大可蓄水量約３億立方米，目前蓄水量約１億立方米，上下游 水頭差近６０米，近期水位每天持續上漲，既淹上游又對下游 構成嚴重威脅，必須及時加以主動處置。矯勇說，針對唐家山 堰塞湖險情的嚴峻形勢，水利部已要求並協調部隊對上游水位 及壩體變化進行２４小時實時監控，及時發佈預警預報，適時 啟動相應人員轉移預案。工作組組織專家抓緊研究制定了工程 除險方案，武警水電部隊正在做施工前的各項準備，施工人員 已先行進場，國家防總２２日緊急從山東、江蘇空運應急除險 物資至現場。目前，各項應急處置工作均在緊鑼密鼓地進行。

Sichuan Vs Tang Shan Similar  Great

magnitude  Poorly-built buildings  High population density

Sichuan Vs Tang Shan Different Sichuan  Know the news about the earthquake immediately  More people concern  More donation & less destruction  Affected areas are 100,000square kilometers and 28 provinces

Tang Shan  Chinese government refused the foreign aid  People hard to get the information about the earthquake  Huge destruction  Affected areas were 30,000square kilometers and 14 provinces

What can we do 2.

Donations: Money

4.

Books

6.

Toys

8.

Food





Voluntary work

•

Visit the victims such as injuries and orphans

•

Reconstruction work such as house rebuilding

Some voluntary work requires some skills. Make sure that you have that skill before you apply to them

Source httpwww.hko.gov.hkgtsequakeequake_sic huan_e.htm  httpwww.ifrc.orgdocsappeals08MDRCN00 304.pdf  Wiki  Yahoo Knowledge  http://www4.tcgs.tc.edu.tw/lib/network/geo graphy1.htm 

The End