Report on Las Pilas (Nicaragua) — July 1980
Scientific Event Alert Network Bulletin, vol. 5, no. 7 (July 1980)
Managing Editor: David Squires.
Las Pilas (Nicaragua) Minor fumarolic activity
Please cite this report as:
Global Volcanism Program, 1980. Report on Las Pilas (Nicaragua). In: Squires, D. (ed.), Scientific Event Alert Network Bulletin, 5:7. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198007-344080.
12.495°N, 86.688°W; summit elev. 1088 m
All times are local (unless otherwise noted)
Minor fumarolic activity continued in June, and an area of recently-killed vegetation was observed on the NNE flank. The Las Pilas complex last erupted 29-31 October 1954, producing explosions from the central crater El Hoyo.
Geologic Background. Las Pilas volcanic complex, overlooking Cerro Negro volcano to the NW, includes a diverse cluster of cones around the central vent, Las Pilas (El Hoyo). A N-S-trending fracture system cutting across the edifice is marked by numerous well-preserved 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. 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, the only historical eruptions of Las Pilas took place in the 1950s from a fissure that cuts the eastern side of the 700-m-wide summit crater and extends down the N flank.
Information Contacts: R. Stoiber and S. Williams, Dartmouth College; M. Carr and J. Walker, Rutgers Univ.; A. Creusot, Instituto Nicaraguense de Energía.