Report on Las Pilas-El Hoyo Complex (Nicaragua) — March 1993
Bulletin of the Global Volcanism Network, vol. 18, no. 3 (March 1993)
Managing Editor: Edward Venzke.
Las Pilas-El Hoyo Complex (Nicaragua) Weak fumarolic activity
Please cite this report as:
Global Volcanism Program, 1993. Report on Las Pilas-El Hoyo Complex (Nicaragua) (Venzke, E., ed.). Bulletin of the Global Volcanism Network, 18:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199303-344080
Las Pilas-El Hoyo Complex
Nicaragua
12.4922°N, 86.6786°W; summit elev. 1088 m
All times are local (unless otherwise noted)
El Hoyo's main fumarole was emitting vapor at usual levels on 6-7 January.
Geological Summary. Las Pilas-El Hoyo volcanic complex, overlooking Cerro Negro volcano to the NW, includes a diverse cluster of cones within about a 3-km-diameter area. A N-S-trending fracture system cutting across the edifice is marked by numerous flank vents, including maars, that are part of a 30-km-long volcanic massif. The Cerro Negro chain of cinder cones is listed separately in this compilation because of its extensive historical eruptions and possible distinct magmatic system. The lake-filled Asososca maar is located adjacent to the Cerro Asososca cone on the southern side of the fissure system, south of the axis of the Marrabios Range. Two small maars west of Lake Managua are located at the southern end of the fissure. Aside from a possible eruption in the 16th century, eruptions of Las Pilas took place in the 1950s from a fissure that cuts the eastern side of the 700-m-wide crater and extends down the N flank.
Information Contacts: Andrea Borgia, Instituto Nazionale di Geofisica, via di Vigna Murata 605, 00143 Roma, Italy; B. van Wyk de Vries, Open Univ; Peter J. Baxter, Dept of Community Medicine, Fenner's, Gresham Road, Cambridge, England.