At a press conference sponsored by the State Council Information
Office on Thursday, Li Qianghua, of the China Seismology Bureau
spoke of the efforts made to prepare and mitigate for earthquakes
in the first half of the year.
I. The situation of earthquake disasters in China since
the outlet of 2003
Since the outlet of 2003, 27 earthquakes with magnitude over 5
occurred in China, among which 22 took place in the mainland area,
4 in Taiwan and its adjacent sea waters, and one in South China
Sea. Among them, earthquakes with magnitude 6 and above account for
4, which are the Magnitude 6.8 Jiashi-Bachu earthquake in Xinjiang
Uygur Autonomous Region on February 24th, the Magnitude 6.6
Delingha earthquake in Qinghai province on April 17th, the
Magnitude 6.1 earthquake in the north of Bange County in Tibet
Autonomous Region on July 7th, and the Magnitude 6.2 Dayao
earthquake in Yunnan province on July 21st separately. 8
Earthquakes with magnitude 5 to 6 took place, among which five
occurred in the boundary area between Qinghai Province and Tibet
Autonomous Region, one in Balinzuoqi county - Alukeerqinqi county
area in Inner Mongolia Autonomous Region, one in Yanyuan county in
Sichuan Province, and 11 aftershocks to the main-shock of 6.8
earthquake in the Bachu-Jiashi area in Xinjiang Uygur Autonomous
Region.
Eight among the 22 earthquakes with magnitude over 5 in mainland
area caused casualties and property losses, resulting in the total
fatalities of 291, more than 2200 people seriously wounded, over
4500 people slightly injured, about 1.74 million people affected,
and the direct economic losses reached more than three billion RMB.
The most destructive one is the magnitude 6.8 Bachu-Jiashi
earthquake in Xinjiang Uygur Autonomous Region with 268 deaths,
2058 seriously injured, about 650,000 victims, and the direct
economic loss amounted to 1.3 billion RMB. It is the most
devastating continental earthquake of China since the Lijiang
earthquake of Yunnan Province in 1996.
II. The earthquake preparedness and disaster mitigation
in China
Earthquake is a natural disaster which may cause tremendous
losses to mankind. With the economic development and acceleration
of urbanization, earthquake disaster could result in greater
economic losses and bigger social catastrophe. China is an
earthquake-prone country with severe seismic disasters. With the
land area covering only 7% of the world, 33 percent of the global
continental destructive earthquakes occurred in China in 20th
century. Nearly 600,000 people were killed by earthquakes in China
in the last century, accounting for 50% fatalities caused by
earthquake during the same period all over the world. The two
earthquakes with death toll over 200,000 in 20th century both
occurred in China. One is the Magnitude 8.6 Haiyuan earthquake in
Ningxia Hui Autonomous Region in 1920 with the death toll of over
230,000, and another one is the Magnitude 7.8 Tangshan earthquake
in 1976 which killed 240,000 lives.
The reason why China has been suffering from earthquake disaster
so severely is that China is located between the Pacific plate and
the Indian plate, where the crustal tectonic movement is intensive
and complex, which makes the seismicity in China characterized by
the following features:
a.?High frequency, high intensity
In 20th century, there were 8 earthquakes with magnitude 8 and
above, 65 between 7 and 8, and 382 between 6 and 7, which accounts
for one third of the world continental destructive earthquakes.
b. Wide distribution
According to historical records, destructive earthquakes with
magnitude 5 and above occurred in every province (autonomous region
and municipality) in China, and 29 provinces (autonomous regions
and municipalities) hit by destructive earthquakes with magnitude 6
and above.
c. Severe disaster situation
Due to the above mentioned features of earthquake disaster in
China, earthquake hazard is fatal in China. 41 percent territory of
mainland area and about 70 percent big cities with population above
one million are located in high intensity zone with the seismic
intensity of and above VII. In addition, being a developing
country, China is still relatively weak for its capability of
seismic design for buildings and structures on the whole. Hence,
China is a country with severe earthquake disasters.
Chinese government has attached great importance to the efforts
of earthquake preparedness and disaster mitigation which concerns
people's life and property security. Since founding of the People's
Republic, especially in the past ten more years, efforts of
earthquake preparedness and disaster mitigation in China have
witnessed great achievement and played important role in social and
economic development.
· Ability of earthquake monitoring and prediction has steadily
improved
Earthquake monitoring and prediction is the fundamental link and
top priority for the effort of earthquake preparedness and disaster
mitigation, since a successful earthquake prediction may greatly
reduce life losses and injuries. At present, over 400
national-level and province-level seismic stations and more than 30
regional telemetric seismic networks have been set up, in addition
to about 1400 seismic stations owned by local governments and
enterprises, as well as more than 8000 observation points run by
volunteers. During the period of ninth "Five-Year-Plan" from 1996
to 2000, observation approaches of the seismic stations had been
digitally upgraded, and China Crustal Movement Observation Network,
which is based on Global Positioning System (GPS), had been
established. Seismic monitoring system of China has shifted from
single-station observation to network observation and from analog
technique to digital technique, and has been integrated into a
national seismic network of multi-discipline and multi-subject of
observation. Earthquakes with magnitude 4.0 or above could be
effectively monitored nationwide, 1.5 to 2.0 in eastern important
provincial capitals and their neighboring areas, and 1.0 to 1.5 in
the Capital Circle Area.
Since 1966 Xingtai earthquake, China has strengthened
exploration in the practice of earthquake prediction. The
successful prediction to 1975 Magnitude 7.3 Haicheng earthquake in
Liaoning Province which greatly avoided fatalities is the first one
in human history. In recent years, predictions to certain extent
have been realized to the destructive earthquakes with magnitude
above 5.0, such as 1999 Xiuyan earthquake in Liaoning Province.
However, earthquake prediction, especially impending earthquake
prediction remains an unsolved scientific issue worldwide, and
earthquake prediction is still at a quite low level.
· Resistance to earthquake disaster strengthened
Human life and property losses by earthquake disasters are
mainly caused by collapse and damage of buildings; hence aseismic
design for the buildings is of key importance. Effort of earthquake
disaster prevention mainly pays off in the following aspects. The
first one is that fundamental work for aseismic design has been
gradually strengthened. Seismologists have compiled seismic
intensity map and seismic zoning map, which provides scientific and
reasonable standard of aseismic design for common civil buildings,
and at the same time carried out seismic micro-zoning, earthquake
disaster estimation and active fault detection for cities, which
have laid foundation to improve earthquake preparedness and
disaster mitigation in cities. The second one is that supervision
and inspection to aseismic design of construction projects have
been gradually strengthened. The administrative authority has
regarded aseismic design as one of the important contents of
quality control in the construction projects, especially the key
procedures of key projects, such as site survey, design and
construction. For instance, earthquake safety assessments had been
carried out for the projects of the huge Three Gorges Project,
Dayawan Nuclear Power Plant, Gas Transportation from the West to
the East, Qinghai-Tibet Railway etc. and the projects could
possibly cause severely secondary disasters otherwise. The third
one is that reinforcement work to the buildings with weak
resistance to earthquakes has been actively carried out in the
earthquake monitoring strengthened area, which made resistant
ability of the buildings to earthquake obviously increased. The
fourth one is that instruction to aseismic design for the farm
houses and public facilities in village and town has been
strengthened. Technical advisory has been given via publicity and
education to push forward the work of aseismic design in village
and town.
· Effort of earthquake disaster emergency response has been
initiated
According to the data of Tangshan Earthquake, the survival rate
was 80 percent if the buried people could be rescued within one
day, and 53 percent within 2 days, but only 7 percent could be left
in the fifth day. To meet the requirement of in-situ emergency
rescue and relief work for the earthquakes home and abroad, the
first National Earthquake Disaster Emergency Relief and Rescue Team
was established in 2001. The 230-person team consists of military
engineering unit, seismologists and medicals, and is equipped with
advanced tools for search and rescue, medical treatment, cutting
and expanding, and sniffer dogs. The team participated in the
relief and rescue work in Bachu-Jiashi earthquake in Xinjiang Uygur
Autonomous Region and Algeria earthquake, made contribution to the
post-quake relief work in the quake stricken areas.
Working out earthquake emergency preplan is one of the
significant approaches for earthquake preparedness and disaster
mitigation. It makes it possible to have prompt response to the
earthquake emergency and to carry out work in an orderly manner
once earthquake occurs so as to avoid the losses resulted from
inappropriate command and sluggish response. Governments at various
levels and governmental departments concerned have been actively
working out and improving earthquake emergency preplans. They have
set up the aids warehousing system for disaster relief and rescue.
They are in charge of the implementation as well as the supervision
of countermeasures for emergency relief and rescue. At present, the
national earthquake emergency preplans at different levels and
different departments have been formed and played significant roles
in the earthquake disaster relief work thereafter.
· Significant progress has been made in legislation of
earthquake preparedness and disaster mitigation
Legal system of earthquake preparedness and disaster mitigation
is the key to guarantee the function of earthquake preparedness and
disaster mitigation of a society. With the promulgation and
implementation of the Law of the People's Republic of China on
Protecting Against and Mitigating Earthquake Disasters, which
has come into force since March 1998, together with the associated
ordinances, such as the Ordinance of Earthquake Prediction
Management, and the Ordinance of Seismic Safety Evaluation,
the work on administration, legal regulation, supervision and
checking system has been gradually enhanced. The management on
earthquake preparedness and mitigation has stood its track on
standardization and legalization.
· The overall awareness of the general public has been
improved
Strengthening the publicity of earthquake knowledge to improve
the social consciousness is an effective approach for earthquake
preparedness and disaster mitigation. Through years efforts on the
publicizing the earthquake knowledge, the public's involvement in
earthquake preparedness and disaster mitigation has been gradually
enhanced. The capabilities of discriminating quake rumors and the
skills on how to avoid casualties in a quake and on how to carry
out self rescue and mutual rescue have been steadily improved.
On the other hand, we should know clearly that there are still
quite a lot of difficulties and problems in earthquake preparedness
and disaster mitigation. There is still a relatively big gap
between our capability of earthquake monitoring, prediction and the
social requirement. The aseismic capability for the structures in
some area and buildings is lower than it should have met with; due
to the code of aseismic design had not been strictly followed. The
emergency rescue capacity is far from the requirement of our quake
prone-disaster situation, and a complete set of system of emergency
relief and rescue has not been set up. In the meantime, the overall
awareness of earthquake knowledge for the whole nation should be
upgraded to a higher level.
III. The main approaches for the improvement of the
capability of earthquake preparedness and disaster
mitigation
The National Conference of Earthquake Preparedness and Disaster
Mitigation held by the State Council in 2000 reiterated that the
highlights for earthquake preparedness and disaster mitigation in
the forthcoming period of time should be focused on the following
aspects, i.e. further perfecting the system of earthquake
monitoring and prediction, which should mainly rely on the experts
combined with those amateurs; establishing the system of quake
disaster preparedness which has to strictly abide by the relevant
laws or ordinances and should be always on high alert; setting up
the prompt responding and effective force of emergency relief and
rescue system. Only through the organic combination of all these
efforts can we improve the integrated capabilities of earthquake
monitoring and prediction, aseismic design for buildings and
structures and emergency relief and rescue.
In order to further strengthen the construction of
earthquake-related infrastructures and improve the capability of
earthquake preparedness and disaster mitigation, during the 10th
Five-Year Plan period, the Central and local governments will have
a total investment of about 2.7 billion RMB for the construction of
the project of "China Digital Earthquake Observation Network". The
project will focus on the construction of seismometric network,
precursory observation network as well as the network for strong
ground motion observation; it will also involve the three technical
systems covering the detection for active faults, the
information-sharing services and the emergency commanding
facilities. The project will be finished by the end of 2007. A
digitalized, high precision and prompt responding earthquake
observation network with coverage of the whole country will be
formed at that time, able to provide fundamentally scientific data
for urban planning and construction. Through the implementation of
this project, the overall capabilities of earthquake monitoring and
prediction, disaster preparedness and mitigation as well as
emergency relief and rescue will be greatly improved.
(China.org.cn September 5, 2003)