Date:         Thu, 5 Jan 1995 20:42:40 MST
Subject:    Clarification of USGS role in sending scientists to
            Mexico to assist at Popocatepetl
To:               Multiple recipients of list VOLCANO
From:       C. Dan Miller, USGS/OFDA Volcano Disaster Assistance
Program

Unfortunately, the article titled: "USGS scientists head for Mexico
to help during volcanic emergency at Popocatepetl volcano," that
appeared on the Listserv on 1 January, did not mention extensive
monitoring efforts by Mexican scientists that have been underway
for more than a year.  The above-mentioned statement by the USGS
was included on the WWW Home Page for the Cascades Volcano
Observatory to describe ongoing activities by CVO scientists.  The
statement does not make it clear that the USGS will play a
collaborative role by assisting colleagues in Mexico to monitor and
assess hazards at Popocatepetl.

Prior to the beginning of the current eruptive episode at
Popocatepetl, scientists at the National University of Mexico
(UNAM), in conjunction with the National Disaster Prevention Center
(CENAPRED), had installed a four station, telemetered-seismic
network at Popocatepetl and established a geodetic network at the
volcano.  USGS scientists will assist Mexican scientists to augment
existing seismic- and deformation-monitoring efforts.  Scientists
at the University of Colima, in collaboration with scientists from
UNAM and from Arizona State University, have been collecting data
on SO2 emissions for about a year.  Furthermore, scientists at UNAM
have been investigating the eruptive history of Popocatepetl and
evaluating volcanic hazards at the volcano for several years.
Since the initial eruptive activity on 21 December, all monitoring
and hazard-assessment activities at Popocatepetl have been
coordinated by CENAPRED, the agency responsible for mitigating
natural hazards in Mexico.

U.S. Geological Survey scientists are in Mexico at the invitation
of CENAPRED to collaborate with Mexican scientists, who are
investigating the volcano.   USGS scientists will assist their
Mexican colleagues with monitoring and other activities, where
possible, but will play a subordinate role in the ongoing hazard-
mitigation efforts at Popocatepetl.