M 7.9 - EASTERN SICHUAN, CHINA

Monday, May 12, 2008 at 06:28:01 UTC
Location: 31.0°N 103.4°E Depth: 19km

Summary

Estimated Population Exposed to Earthquake Shaking

Est. Modified Mercalli Intensity	Est. Population Exposure (k = x1000)	Perceived Shaking	Potential Structure Damage
Est. Modified Mercalli Intensity	Est. Population Exposure (k = x1000)	Perceived Shaking	Resistant	Vulnerable
X	603k	Extreme	V. Heavy	V. Heavy
IX	692k	Violent	Heavy	V. Heavy
VIII	4,301k	Severe	Moderate/Heavy	Heavy
VII	12,396k	Very Strong	Moderate	Moderate/Heavy
VI	15,484k	Strong	Light	Moderate
V	89,480k	Moderate	V. Light	Light
IV	192,012k*	Light	None	None
II-III	--*	Weak	None	None
I	--*	Not Felt	None	None

*Estimated exposure only includes population within the map area.

Population Exposure

Population per ˜1 square km from Landscan 2005

Selected City Exposure

MMI	City	Population
VIII	Jiangyou	127k
VIII	Tianpeng	60k
VIII	Mianyang	264k
VII	Deyang	152k
VII	Linqiong	55k
VII	Chengdu	3950k
VII	Guangyuan	213k
V	Xi'an	3225k
V	Nanchong	7150k
V	Chongqing	3967k
IV	Shiyan	3460k

Shaking Intensity

MMI

Overall, structures in this region are vulnerable to earthquake shaking, though some resistant structures exist. A magnitude 6.4 earthquake struck the Sichuan, China region on August 23, 1976 (UTC), with estimated population exposures of 1,500 at intensity IX or greater and 5,700 at intensity VIII, resulting in 41 deaths. Additionally, a magnitude 7.3 struck this region in 1933 killing 6,800 people. Recent earthquakes in this area have also triggered landslide hazards that have contributed to losses. Users should consider the preliminary nature of this information and check for updates as additional data becomes available.

PAGER results are generally available on the Internet within 30 minutes of the earthquake's occurrence. However, information on the extent of shaking will be uncertain in the minutes and hours following an earthquake and typically improves as additional sensor data and reported intensities are acquired and incorporated into models of the earthquake's source. Users of PAGER exposure estimates should account for uncertainty and always seek the most current PAGER release for any earthquake.

Maps

[Population | Shakemap]

Map of MMI contours plotted over population per ˜1 square km (see gray scale bar on top of map). The regions of integer MMI values are separated by the thick contour lines and labeled with Roman numerals. The total population exposure to a given MMI value is obtained by summing the population between the thick contour lines. This total is shown in population exposure table.

Map of shaking intensity. This map shows the estimated MMI as a continuous color scale. The ground shaking estimates can be obtained from http://earthquake.usgs.gov/shakemap/.

Exposure

Est. Modified Mercalli Intensity	Est. Population Exposure (k = x1000)	Perceived Shaking	Potential Structure Damage
Est. Modified Mercalli Intensity	Est. Population Exposure (k = x1000)	Perceived Shaking	Resistant	Vulnerable
X	603k	Extreme	V. Heavy	V. Heavy
IX	692k	Violent	Heavy	V. Heavy
VIII	4,301k	Severe	Moderate/Heavy	Heavy
VII	12,396k	Very Strong	Moderate	Moderate/Heavy
VI	15,484k	Strong	Light	Moderate
V	89,480k	Moderate	V. Light	Light
IV	192,012k*	Light	None	None
II-III	--*	Weak	None	None
I	--*	Not Felt	None	None

*Estimated exposure only includes population within the map area.

Table showing population exposed to different estimated Modified Mercalli Intensity (MMI) levels and the possible damage at different intensity levels for resistant and vulnerable structures. MMI describes the severity of an earthquake in terms of its effect on humans and structures and is a rough measure of the amount of shaking at a given location. Unlike earthquake magnitude, intensity varies with distance from the fault, and is influenced by the depth of the earthquake and the types of soils in the shaken region. Population outside the map bounds are not included in the totals.

Cities

MMI	City	Population
VIII	Jiangyou	127k
VIII	Tianpeng	60k
VIII	Mianyang	264k
VII	Deyang	152k
VII	Linqiong	55k
VII	Chengdu	3950k
VII	Guangyuan	213k
VI	Tongchuan	58k
VI	Langzhong	60k
VI	Zengjiahe	1k
VI	Pujichang	2k
VI	Dongxichang	4k
VI	Nanlong	63k
V	Leshan	154k
V	Ziyang	87k
V	Changchi	1k
V	Suining	124k
V	Xialianghekou	1k
V	Hanzhong	145k
V	Chonglong	58k
V	Luocheng	73k
V	Xi'an	3225k
V	Zigong	689k
V	Neijiang	546k
V	Nanchong	7150k
V	Gaoping	204k
V	Beidao	74k
V	Hechuan	97k
V	Yongchuan	94k
V	Chongqing	3967k
V	Daxian	130k
V	Yibin	242k
V	Guozhen	85k
V	Xunchang	64k
V	Xichang	126k
V	Yuxia	60k
V	Jiangjin	61k
V	Linxia	202k
V	Xianyang	1034k
V	Lanzhou	3200k
IV	Wanxian	188k
IV	Yudong	81k
IV	Beibei	112k
IV	Fubaochang	3k
IV	Changsha	1k
IV	Xiantanchang	1k
IV	Caijiagang	2k
IV	Fuling	166k
IV	Guandu	2k
IV	Zhaotong	109k
IV	Pingliang	108k
IV	Yanliang	60k
IV	Lintong	75k
IV	Weining	56k
IV	Guofuchang	1k
IV	Shijiaochang	2k
IV	Weinan	172k
IV	Puhechang	1k
IV	Dongxi	7k
IV	Ganshui	5k
IV	Sanchahe	1k
IV	Taipingdu	3k
IV	Liangcunchang	1k
IV	Wenshui	5k
IV	Lichuan	72k
IV	Sangmu	1k
IV	Songkan	4k
IV	Xinzhan	2k
IV	Shiyan	3460k
IV	Huaqiuba	1k
IV	Yuncheng	201k
IV	Enshi	95k
IV	Chumi	3k
IV	Bijie	77k
IV	Baiyin	188k
IV	Loushanguan	80k
IV	Changde	517k
IV	Tongchuan	223k
IV	Panzhihua	461k
IV	Gucheng	74k
IV	Zunyi	466k
IV	Laohekou	253k
IV	Shiyan	408k
IV	Dabachang	1k
IV	Yichang	476k
IV	Dengzhou	59k
IV	Buhe	106k
IV	Jinshi	82k
IV	Zhijiang	60k
IV	Yicheng	61k
IV	Xiangfan	462k
IV	Majie	131k
IV	Xujiaba	3k
IV	Danjiangkou	92k
IV	Jingzhou	177k
IV	Xinye	61k
IV	Anshun	351k
IV	Qujing	146k
IV	Jishou	102k
IV	Zhicheng	159k
IV	Nanmuping	1k
IV	Ankang	132k
IV	Xining	767k
IV	Linfen	232k
IV	Shiqian	9k
IV	Jiangkouxu	1k
IV	Hancheng	58k
IV	Kunming	1023k
IV	Anxiang	57k
IV	Dali	134k
IV	Zhangjiajie	86k
IV	Bahuang	1k
IV	Jinhe	3k
IV	Nanzhang	83k
IV	Tongren	90k
IV	Tanwan	1k
IV	Shuidatian	1k
IV	Chadian	1k
IV	Chatian	1k
IV	Zhushi	2k
IV	Ma'an	1k
IV	Xiaoweizhai	58k
IV	Youyupu	1k
IV	Jingmen	167k
IV	Changzhi	699k
IV	Yangtou	1k
IV	Lanli	1k
IV	Zhujiachang	1k
IV	Bangdong	1k
IV	Shijiang	9k
IV	Ouyang	1k
IV	Wantouqiao	1k
IV	Qinglang	2k
IV	Yaoshi	1k
IV	Duyun	91k
IV	Longtan	2k
IV	Lianyuan	66k
IV	Yanmen	1k
IV	Dengjiapu	2k
IV	Shangmei	75k
IV	Anping	2k
IV	Pingjiang	1k
IV	Yima	82k
IV	Bozhou	1k
IV	Xiajiang	1k
IV	Zhongzhai	1k
IV	Yiyang	202k
IV	Shanmen	3k
IV	Dongshan Dongzuxiang	1k
IV	Huaihua	127k
IV	Xiaolongmen	1k
IV	Luojiu	2k
IV	Huaqiao	2k
IV	Luyang	3k
IV	Huomachong	1k
IV	Runsonglaozhai	1k
IV	Qimeng	1k
IV	Biyong	1k
IV	Xinzhi	72k
IV	Huangmaoyuan	1k
IV	Tuokou	2k
IV	Longtou'an	2k
IV	Gaoniang	2k
IV	Lantian	1k
IV	Tongwan	2k
IV	Qiancheng	9k
IV	Huangxikou	1k
IV	Dengyuantai	2k
IV	Guiyang	1171k
IV	Qiaojiang	3k
IV	Jiangshi	1k
IV	Baishi	1k
IV	Xianrenwan	1k
IV	Zhongfang	1k
IV	Shuangxi	1k
IV	Maoping	1k
IV	Benchu	1k
IV	Anjiang	55k
IV	Xiaohenglong	1k
IV	Pingjiang	1k
IV	Liangyaping	1k
IV	Puzi	1k
IV	Gangdong	1k
IV	Dabaozi	1k
IV	Tonggu	1k
IV	Hongjiang	59k
IV	Ruoshui	1k
IV	Gaoyi	1k
IV	Longlisuo	2k
IV	Xiaoshajiang	2k
IV	Zhaishi Miaozudongzuxiang	3k
IV	Xixi	2k
IV	Zhongchao	2k
IV	Hengbanqiao	1k
IV	Hongqiao	58k
IV	Aoshi	1k
IV	Huangjinjing	1k
IV	Shuiche	3k
IV	Tingdong	1k
IV	Pukou	1k
IV	Loudi	150k
IV	Hexiangqiao	4k
IV	Jinshiqiao	1k
IV	Simenqian	5k
IV	Huayuan	1k
IV	Guilin	649k
IV	Dundong	1k
IV	Gaoqiao	1k
IV	Gaozeng	1k
IV	Liuduzhai	8k
IV	Huangtukuang	1k
IV	Darong	1k
IV	Xianxi	2k
IV	Zhuzhoujiang Miaozuxiang	1k
IV	Tangjiafang	1k
IV	Hongzhou	1k
IV	Boyang	1k
IV	Lengshuijiang	115k
IV	Wuyang	2k
IV	Xishan	1k
IV	Lixiqiao	1k
IV	Yatunpu	1k
IV	Huangqiao	2k
IV	Gaowu	1k
IV	Shuangjiang	8k
IV	Linkou	2k
IV	Jiangfang	1k
IV	Xiyan	3k
IV	Maoping	2k
IV	Qingxi	1k
IV	Malin	2k
IV	Qiyang	66k
IV	Huanglong	1k
IV	Baisha	2k
IV	Qingjiangqiao	1k
IV	Yaoshi	1k
IV	Yongfeng	70k
IV	Lengshuitanqu	88k

Table of MMI estimates and populations for settlements falling within the map boundaries. The settlement name, location, and population are obtained from the freely-available GeoNames geographical database.

Downloads

Details

Magnitude	7.9
Max MMI	X
Date-Time	Monday, May 12, 2008 at 06:28:01 UTC
Location	30.986°N, 103.364°E
Depth	19.0 km (11.8 miles)
Event ID	US2008RYAN
Version	11

Additional Information