CHINA: Wenchuan Earthquake Management

CHINA: Wenchuan Earthquake Management - Ground Realities

Guest Column by Dr Sheonandan Pandey

(The views expressed by the author are his own)

The People’s Republic of China (PRC) has consistently been improving its space based infrastructure. In 28 years since the first successful launch of Dong Fang Hong-1 Satellite into orbit on 24 April 1970, the PRC has demonstrably scaled many a reckonable technological step. The space missions that the PRC launches today include: recovery capsules and non-capsule remote sensing satellites; communication/ broadcasting satellites; metrological satellites; science satellites; engineering test satellites; positioning satellites; and, manned space satellites. China’s goals and objectives for going into orbit with a variety of space assets including manned are predictably similar to those that drove the Russian and the US- to gain national prestige, and to signal wealth, commitments and technological prowess.

Development of space infrastructure has wide ranging applications, which includes meeting environmental challenges. Earth observation (EO), telecommunications and navigation systems together can be used to monitor evolution of fault lines, landslides, subsidence, seismic tremors and outburst of volcanoes. Some of the components of the space infrastructure such as the Global Navigation Space System (GNSS) and space based augmentation system (SBAS), Geographic Information System (GIS), miniaturized computer components, automatic control and in-field and remote sensing have veritable potential to provide useful input to disaster management information systems.

As being earthquake prone country, the PRC is live to the need to merge the traditional earthquake prediction methods, tools and techniques with the modern technology based western approaches. There have been 9 earthquakes larger than a grade of 8 on Richter scale in north-south earthquake zone from 1739, and 7 of them after 1897, when the greatest one was at Haiyun in 1920 and at Chayu in 1950, both of them measured 8.5. The Wenchuan earthquake on May 12^th, 2008, measured 8, and was strong enough to sway buildings in Beijing (1500 km) and Shanghai (1700 km). In Wenchuan earthquakes, the worst hit areas included Beichuan and Qingchuan with earthquake measured at 11, with the maximum being 12 by the Chinese seismic survey standards.

It was cataclysmic natural disaster. It left 5 million people homeless, killed 69170 people and injured 368545 others. As many as 18830 people are yet officially listed as missing ones. Notwithstanding, cracks in Tangjiashan Barrier Lake in Beichuan County had posed danger of inundating area inhabited by 1.3 million people. It took six days to dig 475 meters long and 12 meters wide diversion channel to divert 89000 cubic meters of water. Life in the affected areas of Sichuan and adjoining provinces in southwest China could limp back to near normalcy not until late July 2008 despite deployment of over 133000 People’s Liberation Army (PLA) and People’s Armed Police Force (PAPF) personnel.

After five months of hectic rescue and relief operations, the Chinese State Council declared termination of its “General Headquarters of Earthquake Relief” on 14^th October 2008. In its resolution, the State Council eloquently noted the contributions of “local people and officials in the affected areas, members of the PLA and the PAPF, and people from all circles under the direct leadership of the party organization and governments in the affected areas”. In finality, the State Council meeting declared that the earthquake relief had come to a phase of rehabilitation, which was to take about three years to complete. This was simultaneously the 26^th and the last meeting of the General Headquarters of Earthquake Relief, set up under the Chairmanship of the Chinese Prime Minister Wen Jiabao to oversee the relief and rescue operations.[1] The resolution, tabled by the Chinese Premier, had unequivocal support of all those who wield present and hold prospect for future Chinese leadership such as vice Premier Li Keqiang, vice Premier Hui Liangyu, State Councilor and State Council Secretary General Ma Kai, and State Councilor and Minister of Public Security Meng Hianzhu. While a bygone issue, it is a puzzle that the Chinese leadership did not have a word about the contribution of China’s space based infrastructure in the whole gamut of disaster management.

In this backdrop, the paper goes to study the role, and thereby, throw light on the capabilities of China’s space based infrastructure in disaster management during the Wenchuan earthquake. The paper aims at bridging information gap and drawing lessons from the Chinese experience. The focus of the study, accordingly, lay on: the system requirement and China’s space assets; Wenchuan Earthquake and the Support Function of the Chinese Space Based System; and last but not the least, the efficacy of the Chinese space assets in disaster management. As space assets are characterized to have dual use, the paper would peep into the plausible military applications of the Chinese space assets.

System Requirement and China’s Space Assets

Chinese earthquake prediction research traditionally takes cue from intuitive techniques, much of which went to look into and draw inferences from unusual events before the earthquake. It included changes in the ground water levels, strange animal behaviour and foreshocks. In a blog, Li Shihui, a researcher with the Institute of Geophysics and Geology, Chinese Academy of Sciences (CAS), claimed absolute relationship between incidents of drought and earthquake. He credited Geng Qingguo, Wang Chenmin, Ren Zhenqiu, and Wand Dixing for their predictions, much ahead May 12 Wenquan earthquake.

While crude in form, the Chinese traditional approach to earthquake prediction does have a window on scientific factors. Earthquake produces seismic waves. The first wave detected by the modern seismological stations is called P-wave. The Chinese system goes by the premise that the animals are susceptible to sonar stimulants and hence, change in the behaviour of animals follows detection P-waves days and hours ahead of occurrences. Interestingly, the modern age earths scientists do as well draw on P-wave to track back the time and epicenter of earth quakes.

The track record of this Chinese approach has been not that bad. Haicheng city in northeast China’s Liaoning province was hit by earthquakes on 04^th February 1975. It measured 7.3 Richter scale. It was again hit in November 1999. The intensity was relatively low at 5.4 Richter scale. While damage to property was inevitable, prediction in advance 4-5 days saved a large number of precious lives. However, in contrast, in the case of July 1976 Tangshan earthquakes and May 2008 Wenquan Earthquake, the Chinese systems did not have inklings, much less a clear cut prediction.

Precise prediction hitherto eludes despite reckonable scientific and technological advancements in the field of seismological studies. Among the terrestrial approaches, the use of ultrasound imaging technique, developed by the Scripps Institute of Oceanography enable onset of earthquake 10-20 minutes ahead of occurrence. The PRC did not have access to this technique until May 2008 Wenquan earthquake. It did have in place space based technology, which, inter alia, requires articulation for earth observation (EO), navigation and telecommunications systems.

Earth observation system normally constitutes of an array of the geostationary and polar satellites. They are specially designed to observe earth from orbit, similar to reconnaissance satellites. While geostationary satellites hover over the same spot, and provide continuous monitoring to a particular portion of Earth, the polar satellites provide global coverage, but only twice per day at any given spot. While remote sensing satellites play quite critical role, the contribution of weather satellites can not be glossed in EO function.

In the past three and half decades, Chinese aerospace establishments have successfully developed and launched over 50 satellites of various kinds, half of which could be earth observation satellites. Strikingly, the technological range of EO satellites is both diverse and large. Outcome is accordingly technology dependent, in particular, the elements of sophistication in payloads. Optical earth observation satellites, launched at different points of time fall in three categories: recoverable remote sensing satellite; meteorological satellite; and, earth resource satellite.

Chinese recoverable remote sensing satellite has come of age in technological prowess. The latest one constitute of the third generation of film recovery photographic satellite FSW-3 (Fanhui Shi Weixing). The Chinese Academy of Space Technology (CAST) is engaged in the development of these recoverable remote sensing satellites.

15 launches of FSW-0-01, FSW-0-02 and FSW-1, carried out during1974-1996 with three failures, consisted of first generation technological marvel. They carried prism scanning panoramic and frame metric camera respectively. The focal length and swath width of FSW-1 frame metric camera was then comparable to American Space Shuttle’s Orbiter- borne Metric Camera. Design life of this set of satellites has initially been 3-8 days. FSW-2, the second generation Chinese recoverable remote sensing satellite, carried node point panoramic camera in all the three launches between 1992 and 1996. It had design life of 15 days. The first launch of FSW-3 took place in 2003. It carried payload to carry out microgravity related experiments. The design life now ranges between 24-27 days. There have been four launches with same configuration of FSW-3 thereafter. They are all low orbit 3-axis stabilization satellites, which stand oriented to the center of the earth and bear recovery modules. The PRC is scheduled to go for another launch of this set of remote sensing satellite in January 2009. Meanwhile, the PRC built and successfully launched two remote sensing micro-satellite Qinghua-1 in June 2000 and Qinghua-2 in October 2008 respectively. UK based Surrey Satellite Technology had provided necessary technological insight.

There are since three classes of Chinese metrological satellites. The latest of the three classes Feng Yun-3 (FY-3) was launched just one fortnight after the Wenchuan Earthquake from Taiyuan Satellite Launch Center in Shanxi province on 27^th May 08. It carried three dimensional sensors, capable of measuring the dynamics in the Earth’s atmosphere and climate besides monitoring polar region and ocean conditions. The sensor on board is believed to be capable of measuring temperature change of 0.1 F degrees. It has spatial resolution of 250 meters. Feng Yun-1, the first generation of sun synchronous metrological satellite was divided into two batches-Feng Yun-1-01 and Feng Yun-2-02. There were two launches of Feng YUN-1-01 in 1988 and 1990 respectively. While Feng Yun-1-01 carried two 5-channel (visible and IR) scanning radiator, Feng Yun-1-02 had two 10 channel (visible and IR). Two launches of Feng Yun-2 in 1997 and 2000 adapted bi-spin stabilization methods. It had 3-channel (visible and IR) scanning radiator. The design life time of Feng Yun-2 was three years. Future launches of Feng Yun series of Chinese metrological satellites include Feng Yun-2E and Feng Yun-3B in Dec 2008 and September 2009.

The earth resource satellite, launched by the PRC, constitute of Ziyuan series. It is being developed and launched in a joint collaboration with Brazil under Shi Jian-3 Project. It has therefore come to be known as China, Brazil Earth resource Satellite (CBERS).The PRC had put the first of the series Zi Yuan-1 satellite into sun synchronous orbit on 14 Oct 1999. Zi Yuan-2 satellite came to be launched in 2000. Until now, the PRC has thereafter launched Zi Yuan-1-2 satellite, Zi Yuan-2-3 satellite and Zi Yuan 1-2B satellite respectively in Oct 2003, Nov 2004, and Sep 2007. The future launches include Zi Yuan-3 satellite in Mar 2009.

Nonetheless, the PRC then has Shijian series of satellites, the latest one Shijian-6 3A and Shijian-6 3B, launched just on 25 Oct 2008 and Shijian-9 (seedsat-2) to be launched some times in Nov 2008. The payloads in all the previous ones in the series are oriented to provide detailed data on changes in earth crust. Shijian-5 satellite, launched on 10^th May 1999, was oriented to study magnetosphere. It carried semi conductor proton and heavy ion detector, static electrical analyzer, electrical potentiometer, static single event monitor, and dynamic single event monitor. All the predecessors of Shijian-5 satellites were characterized to be distinct technological missions.

To meet the requirements of navigation satellites for the purpose, the PRC has Beidou Navigation System, the latest of which was launched in February 2007. Beidou-1 system, made up of 4 satellites, happened to be experimental. Unlike the GPS, GLONASS, and Galileo systems, Beidou-1 used geostationary orbit. It did not therefore require a large constellation of satellites. In fact, Beidou satellites are based on the Chinese Dong Fang Hong-3, which is geostationary. Beidou-2 is going to have a constellation of 35 satellites, which included 5 geostationary (GEO) and 30 medium Earth orbit (MEO) satellites. Moreover, China is since a member of Galileo positioning system. Besides, China’s third generation imaging satellite, the FSW-3 (Fanhui Shi Weixing), uses a charged coupled device (CCD) array, and, when operating in a 700-km sun synchronous orbit, it is designed to have a five meter resolution. FSW-1 and FSW-2 were equally powerful by virtue by their payloads.

Communication is apparently a top priority. The PRC is up in sleeves with new Zhongxing Chinasat series. It launched Zhongxing-22) 0n 25 Jan 2000, which was equipped with C-Band, UHF Communication and Qudian system. It was perhaps an up date of Dong Fang Hong-3 design, and constituted first in a planned constellation of satellites to be launched through 2010. In between, the PRC has launched Zhongxing-20, Zhongxing-22A, Zhongxing-6B2 and Zhonxing-9 in Nov 2003, Sep 2006, July 2007, and June 2008 respectively. The PRC is well set to launch Zhongxing-8 in Dec 2008. Among them, Zhongxing-22, Zhongxing-20, and Zhongxing-22A are perhaps Feng Huo-1, Feng Huo-2 and Feng Huo-3 military communication satellites respectively. Reports suggest that the PRC now has one dedicated imaging reconnaissance satellite, along with one remote sensing satellite, one meteorological satellite, and one remote sensing micro satellite with potential dual use capabilities. [2]

Wide, broad and panoramic range of applications apart, the efficacy of the spaced based system in prediction, the rescue and relief mission, the prevention of and preparedness for secondary disasters, and last but not the least, disaster assessment and reconstruction efforts stands heavily dependent on compatibility of the ground based system in various forms and shape. In certain cases, the limiting factors transcend beyond corrections. E.O satellites, for example, can take images only at a specific times and dates, depending on orbit and swath width. Time lag is thus inevitable and hence, the chances of missing the incident can not be ruled out. Moreover, the strength of the space based system lay in its technological prowess in photogrammetry and remote sensing. Glitch of any kind and level has potential to affect the outcome.

Wenquan Earthquake and the Support Function of the Chinese Space Based System

Going by the Chinese official version, Wenquan earthquake displayed unusual quiet before quake of 8.0 magnitudes struck the epicenter. Xiu Jigang, Deputy Director, China Seismological Bureau (CSB) is on record to testify that the Wenquan earthquake did not produce foreshocks at all, and the activity level of minor quakes around the epicenter was low for quite a long time before the quake. Xu is again on record to reject suggestions about any kind of anomaly then detected in animal behaviour, underground water and other typical precursors.

This is in stark contrast to innumerable claims and counter claims, in hundreds of blogs, much less some of the news papers, about the failure of the officials to take cognizance, in face of loud and clear evidence. Li Shihui, a researcher with the Institute of Geophysics and Geology, Chinese academy of Sciences, expressed his dismay, and was rather constrained to say in his blog (Box-!) dated12^th May 08 that the things could have been entirely different, provided the mainstream seismologists in China did not ignore the predictions of Geng Qingguo and others.

A news item in Chutian Dushi Bao carried vivid details how 80000 tones of water in Guanyin pool in Enshi County in Hubei province got suddenly drained out and a whirl pool created with a roaring noise. Epoch Time, the Falungong sponsored news paper published a photograph of toads crawling out of the Tong Yang canal in Taizhou, cross the Dongfang bridge, far away in Jiangsu province.[3] In some blogs, the stories quote eye witness account how swarm of ants started heading and sheep getting panicked in Beichuan county of Sichuan province.

Box-1: Li Shihui Blog on prediction of Wenchuan earthquake

“…….Today is May 12, 2008, Chinese Seismologist Geng Qingguo is suffering with tearless grief. In 2006, according to the relationship between drought and earthquake, he predicted that in recent years there would be serious earthquakes of over 7 magnitudes in Aba Autonomous prefecture. After a group discussion on April 26, 2008, the Committee on National Hazard prediction subordinate to Chinese Geophysical Society (CGS) reported that an earthquake of 6-7 magnitude could possibly occur in areas south of Lanzhou, around the borders of Sichuan, Gansu and Qinghai. What more Geng Qingguo clearly indicated that the dangerous point of an earthquake over 7 magnitudes in Aba prefecture is May 8, 2008 (10 days before or later) in accordance with the magnetic storm combinations. Geng Qinguo, an undoubted national treasure, is being excluded by the earthquake experts of main stream, and can only depend on a meagre pension to continue his research. The pity is what this old seismologist said did not make any difference.

I am filled with grief and indignation. I am wondering if there will come a day when national treasures like Geng Qingguo, Wang Chenmin, Ren Zhenqiu and Wang Dixing are not frozen out any more, and freely work for rejuvenation of China.

FORMOSA-3 Taiwanese Satellite had recorded drastic drop in ionospheric density, six to 15 days before May 12, 2008. On 11^th May 2008, it had dropped to half to 600000 charged particles. Chinese space based system did not have an inkling about it. After the epicenter in Beichuan was hit, and colossal damage to life and property was done, the Chinese space based infrastructure picked up 10-odd pictures once the quake hit the epicenter at 1428 hrs (CST). China Remote Sensing Satellite Ground Station found them least useful due to poor quality of images. Chinese mainstream seismologists have tried to explain away the failure to overcast sky stalling effective penetration of both Chinese camera and Chinese infrared device with the system.

First image of the earthquake was taken by Taiwan’s FORMOSAT-II satellite. Prof. Harry Chang, of National Taiwan University immediately shared the imagery with the Chinese Academy of Sciences. It showed a large forest, a school and cluster of residential houses in Beichuanxian damaged beyond recognition. It also showed landslides, covering some 1500 hectares (3705 acres) that blocked the river.

The Institute of Space and Earth Information Sciences (ISEIS) of the Chinese University of Hong Kong collaborated first with the Taiwanese University to analyze FORMOSAT-II imagery of 14^th May 08 to assess the extent of damage in Qushanzhen, Beichuan County. ISEIS also collaborated with the Taiwan University to compare and contrast changes in the water level of Tangjiashan Barrier Lake, based on FORMOSAT-II imagery of 14^th May 08 and 18^th May 08. The first set of imagery of FORMOSAT-II, analyzed and interpreted by the ISEIS, showed formation of 30 quake dams and 34 quake lakes. It also showed areas of landslides on the mountains in Beichuan County; Barrier Lake formed in Jianyang, Tangjiashan; gradual increase in the Width of Tangjiashan Barrier Lake from 230 M (14^thMay 08) to 540 M (18^thMay 08); and, increase in the water surface in Xuanping Janzu township.[4] Until alternate channel was not dug wit use of heavy machinery, air dropped by Russian helicopters, Tangjiashan Lake posed imminent dangers to the lives and property of 1.3 million people in the affected areas.

On specific request from the PRC, German Infoterra and French SPOT Image Co., Ltd. supported China’s effort in rescue and relief operations through quality radar and optical satellite imagery. The former tasked radar satellite TerraSAR-X and the latter optical satellite SPOT-5 to acquire data of affected areas.[5] The two provide satellite imagery to China in just 7 hours after the quake. Chinese organizations in the field to cooperate with German Infoterra and French SPOT Image Co., Ltd. included China’s National Disaster Reduction Center, the State Bureau of Surveying and Mapping, the Ministry of Land Resources, the State Earthquake Administration and the State Council of the Satellite Imagery. They cooperated in interpretation, map compilation and rapid analysis. The rapid mapping experts of German Infoterra and French SPOT Image Co., Ltd. in Europe were largely responsible for preparation of first map sheets, and then annotated map that became available at the ground stations. TerraSAR-X is a radar satellite and operates independent of weather conditions. It has favourable resolution properties as well. Notwithstanding, it coordinated with its extensive network of global receiving stations for the job.

ISEIS of the Chinese University of Hong Kong did as well collaborate with SPOT Image Co., Ltd., Beijing and carried out building damage assessment in Dujianyan. The project team compared two satellite images , a German TerraSAR-X Band 1 M resolution radar image taken on 16^th May 08 and a Quickbird optical satellite image taken on 23^rd May 08, and assessed the degree of building damages in Dujianyan. IT showed 90 per cent of the buildings in the area damaged, 15 per cent of which belonged to settlements. ISEIS also compared the German radar satellite TerraSAR-X image Xuantou County, Mao County, Barrier Lake in Xuanping Qiangzu township and certain other quake affected areas in Sichuan.[6]

At the end of the day, the archived French SPOT Image Co., Ltd and Taiwan’s FOROSAT-II and TerraSAR-X imagery added valuable information in the whole gamut and enabled Emergency Work Group, set up under the Chairmanship of the Chinese Premier Wen Jiabao to provide succor to the victims. As part of the process, the imagery so received was sent to Disaster Prevention and Mitigation Committee (DPMC), who executed the required follow up. The same was true for the video documents of the Beijing No.1 Satellite. In turn, such data works helped DPMC in recognition and assessment of damages suffered in populated areas and to infrastructure, identification of focus areas, and action coordination at the long last. Notwithstanding, the imageries had then helped in getting to know normal levels of rivers and lakes. It helped in preventing further damage to infrastructure through correctives as well.

Efficacy of the Chinese Space Assets in Disaster Management

Quite apparently, as the foregoing discussions boil down, the existing Chinese space based infra structure then did not produce worthwhile imagery for any of the three phases of disaster management efforts. The system did not have much to contribute for disaster prevention and mitigation works for future either. Prediction of earthquake would remain an enigma not until a system is in place to take cognizance of terrestrial geophysics and geology related precursors with space based cognition and identification parameters.

The role of Chinese photogrammetry and remote sensing professionals has been quite reckonable. In the company of foreign professionals, they got deep insights. In phase-I of the disaster management efforts, the Chinese photogrammetry and remote sensing professionals received on-ground-exposure of the latest techniques of interpretation of high resolution imagery that helped in locating buildings that collapsed in the worst hit areas. In phase-II of the disaster management efforts, which sought to meet out and cater prevention and preparedness for secondary disasters, the Chinese photogrammetry and remote sensing professionals got thorough with the system mechanism of handling airborne and space borne optical imagery and radar data that were used for identifying, assessing and decision making in respect of areas prone to secondary disasters like landslides and mudslides, especially those in and around the quake lakes or barrier lakes formed when a land slide plugged a river. They have benefited greatly in the third phase, which has now gone to focus on disaster assessment and reconstruction. It relates to high skills of topographic mapping at 1:10000 scales in the region with an aerial extent of 120000 kms based on the techniques of aerial photogrammetic survey without ground control points, generating information products such as DEM, DOQs and DLGs.

Much of the lacuna in the Chinese system came for discussions in the emergency session of Xiangshan Science Conference (XSSC) in Beijing on 19^th May 08, where 40 top experts in seismology and geophysics got to discuss threadbare different shades of the issue. The top Chinese minds in the field included Prof. Zhang Peizhen from the State Bureau of Seismology (SBS), Prof. Xu Zhiqin from the China Academy of Earth Science (CAES) and Prof Wang Guanqian from Qinghua University. They came out with a wide range of recommendations, some of which speak of the process and system that the Chinese approach hitherto lacked to handle the issue.[7] Box-2 carries the glimpse. The gloat over China lacking reckonable system for forecasts of deadly earthquakes of as large as 8 magnitude is understandable. This is besides the fact that the Chinese did not have a worthwhile and dependable imagery interpretation system in place to support post quake rescue, relief and rehabilitation as well.

Box-2 System Glitch and XSSC Recommendations

(a) Strengthening studies on the sequence of serialized aftershocks

(b) Effective forecasting having tangible and substantial effects

(d) Theoretical expositions to address questions such as the formative mechanism of the nappe structure thrusting earthquakes and objective laws

(e) Nationwide survey of anti quake safety of all public buildings, particularly primary and middle school buildings, hospitals and the like.

The PRC is ostensibly not unaware of the glitch in either the terrestrial or space based system. There are efforts afoot to bridge the gap. In less than a fortnight after the Wenchuan earthquake, China launched Fengyun-III satellite into the orbit. 0n 06^th Nov 2008, china launched two EO satellites, microsatellite Chuangxin-1-02 and Shiyan satellite on Long March- 2 D Carrier rocket. Nevertheless, China has plans to launch Fengyun-IV series by 2013. It will give China a jump start in earth observation mission.

In China as in the rest part of the world, the time lag in prediction of earthquake is almost razor thin. The Taiwanese FORMOSAT-II and the Japanese ALOS Radar Remote Sensing Monitoring device proved capable of getting inklings not more than a minute before the deadly Wenchuan earthquake played havoc. It shall be too much to think that the Chinese EO system will do any better in foreseeable future. It has first to develop spatial data infrastructure to contribute meaningfully to post-quake missions.

The gloat over China lacking reckonable system for forecasts of deadly earthquakes of as large as 8 magnitude is understandable. This is besides the fact that the Chinese did not have worthwhile imagery interpretation system in place to support post quake rescue, relief and rehabilitation as well. The PRC is not unaware of the glitch in either the terrestrial or space based system. There are efforts afoot to bridge the gap. In less than a fortnight after the Wenchuan earthquake, China launched Fengyun-III satellite into the orbit. 0n 06^th Nov 2008, china launched two EO satellites, microsatellite Chuangxin-1-02 and Shiyan satellite on Long March- 2 D Carrier rocket. Nevertheless, China has plans to launch Fengyun-IV series by 2013. It will give China a jump start in earth observation mission.

(Dr. Sheonandan Pandey is a China watcher with a long stint in the Government of India and finally retied from National Technical Research Organization. He can be contacted at sheonandan@hotmail.com)

[1] Jiefang Junbao, 15 Oct 2008.
[2] Fong Tak-ho, “Chinese Scientists Deny spy Satellite Claim”, South china Morning Post, Aug 2, 2001; Frank Sietzen, Jr., “Micro Space Technology Comes to China”, Space.com website.
[3] http://www.enggeo.org/pic-keg/pages/ryzahtm
[4] Chinese Earthquake Administration, Jiefang Junbao, 24 May 08.
[5] http://www..german-info.com; http://www. Gim-international.com/issues/articles/id 1186-The_Sichuan_Earthquake_.html
[6]“The Sichuan Earthquake” by Timo Balz, Wuhan University, China, Bernd Scheuch, Infoterra, Germany and Deren Li, Wuhan University, China, Oct 2008, Vol. 22, Issue No. 10.
[7] China Highlights, May 2008, Helmohtize Geiminschart