catalogo de terremotos para america del sur catalog of earthquakes ...

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and Sternberg (1953) who compiled the earthquakes which have occurred in the
amozon reion.
Since 1982 the seismic, macroseismic and instrumental data, of events
which have occurred in Brazil, are being published in the Revista Brasileira
de Geofisica.
MATERIAL US E)
As has been mentionied above, most of the events in the seismic catalog
for Brazil were definpd by macroseismic information obtained from hooks, annhiaries,
ainclient chron icles, newspapers and more recent reports. In some
cases, it was possible to compi e additional information, principally in the
case of important events: which have occurred after 1900, by personal consultation
in the localities affected or from the local newspapers, published at
the time of tl, vents. In the otller cases, principally for older earthquakes,
an attempt was made to obtain the source of the original reference,
from which important data was cxtracted.
The earthquakes with epicenters determined from instrumental data were
extracted from the ISS bulletins (for tle period 1913-1963), from ISC (since
1964) and from the Earthquake Data File Summary, recompiled by NGSTDC of the
U.S. D~epartment of Commerce (since 1900). After the beginning of the decade
of the 70's and principal ly in the present decade tihe epicentcOs of the
majority of the earthquakes which have occurred in Brazil are determined with
data from the national seismic network, which includes several networks of
local or regional character and first order stations. There are supervised
by the istaci6n SismogrAfica de Brasilia, the Instit,ito Astron6mico e Geofisico
of the USP, the Instituto de Pesquisa s Tecno l 6 gicas, Univers idad Federal
de Rio Grande do Note and the Observatorio Nacional. de Rio de Janeiro.
In the s eismic catalogue, published by Berrocal et a] (1984), tie earthquakes
with macroseislic data are divided in the following categories:
A. With abundant information that allows tile preparation of a map with isoseismal
curves and the determination of the epicenter with fairly good
precision.
B. With sufficient information to determine the affect& area, epicenter
and intensities with fair precision.
C. With reliable information concerning the occurrence, some possibility
to evaluate the observed intensities, but without being able to estimate
the affected area or the epicenter with any precision at all.
D. I)oubtful event, with ldate and location uncertain, without any assurance
about its real occurrence or its nature.
E. Oscillations felt in the hrazilian territory, as an effect of a distant
earthquake, normally occurring in the andean region.
F". False data in the source consulted.