and socioeconomic systems) the devastating 1976 Tangshan
earthquake in China caused fatalities ranging from the official
Chinese Government figure of 242,000 to unofficial estimates as high
as 700,000. Fortunately, building practices in the United States
preclude such a massive loss of life.

Property losses are expected to be higher than in any past earthquake
in the United States. For example, San Francisco in 1906, and
Anchorage in 1964, were both much less developed than today when they
were hit by earthquakes. And the San Fernando earthquake in 1971, was
only a moderate shock that struck on the fringe of a large urban area.
Each of these three earthquakes caused damage estimated at about $0.5
billion in the then current dollars. Estimates of property damage for
the most probable catastrophic earthquake on the Southern San Andreas
(Richter magnitude 8+) and for the less probable but more damaging one
(Richter magnitude 7.5) on the Newport-Inglewood fault, are about $15
billion and $70 billion respectively. By comparison, tropical storm
Agnes caused the largest economic loss due to a natural disaster in
the United States to date but it amounted to only $3.5 billion (in
1972 dollars).

It should be noted, however, that substantial uncertainty exists in
casualty and property damage estimates because they are based on
experience with only moderate earthquakes in the United States (such
as the 1971 San Fernando earthquake) and experience in other countries
where buildings are generally less resistant to damage. The
uncertainty is so large that the estimated impacts could be off by a
factor of two or three, either too high or too low. Even if these
lowest estimates prevail, however, the assessment about preparedness
and the capability to respond to the disasters discussed in this
report would be substantially unchanged.

Assuming a catastrophic earthquake, a variety of secondary problems
could also be expected. Search and rescue operations--requiring heavy
equipment to move debris--would be needed to free people trapped in
collapsed buildings. It is likely that injuries, particularly those
immediately after the event, could overwhelm medical capabilities,
necessitating a system of allocating medical resources to those who
could be helped the most. Numerous local fires must be expected;
nevertheless, a conflagration such as that which followed the Tokyo
earthquake of 1923, or the San Francisco earthquake of 1906, is
i