lahar hazards of fuego volcano, guatemala · from fuego volcano. during any single rainfall event...

by This map is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Location Map Guatemala Base maps from Guatemala 1:50,000 scale series; Chimaltenango quadrangle, (2059 IV); Ciudad de Guatemala quadrangle, (2059 I); Alotenango quadrangle, (2059 III); Amatitlan quadrangle, (2059II) digital data courtesy of Instituto Georafico Nacional, Guatemala. Escuintla; 1985 (2058 IV); Guanagazapa 1982 (2058 I) from best available sources. Digital Bases Maps from Titan Averstar, Inc. Universal Transverse Mercator projection, Zone 15, Horizontal Datum North American 1927, Vertical Datum Mean Sea Level, Spheroid Clarke 1866. 2001 J.W. Vallance, S.P. Schilling, O. Matias, W.I. Rose, and M.M. Howell Area that could be inundated by a lahar having a volume of 1 million cubic meters. Highest probability. Area that could be inundated by a lahar having a volume of 2 million cubic meters. Area that could be inundated by a lahar having a volume of 4 million cubic meters. Area that could be inundated by a lahar having a volume of 8 million cubic meters. Area that could be inundated by a lahar having a volume of 16 million cubic meters. Lowest probability. Areas that could be affected by slope failures, avalanches, and lahars from Fuego volcano. During any single rainfall event or earthquake, some drainages may be affected by slope failures and lahars, while others may be completely unaffected. Debris avalanches and lahars originate within the proximal hazard zone, but are likely to move farther down stream beyond the flanks of the volcano and beyond the limit of this zone. Channels that head on Fuego volcano are subject to lahars generated by debris avalanches, torrential rains, earthquakes. Distal hazard zones are subdivided into five zones on the basis of a range of hypothetical lahar volumes [4]. Other areas that could be inundated by lahars and floods, or be affected by aggradation and channel changes. Lahar Hazards of Fuego Volcano, Guatemala NOTE: Although the map shows sharp boundaries for hazard zones, the degree of hazard does not change abruptly at these boundaries. Rather, the hazard decreases gradually as distance from the volcano increases (small volume events are more common than large volume events). In addition, for lahars, the hazard decreases rapidly as elevation above the valley floor increases. Areas immediately beyond outer hazard zones should not be regarded as hazard− free, because the boundaries of hazard zones can be located only approximately, especially in areas of low relief. Many uncertainties about the source, size, and mobility of future events preclude locating the boundaries of zero− hazard zones precisely. Numerals in brackets refer to end notes in the report. Carretera 2 Alotenango C a r r e t e r a 1 4 Guadelupe Finca San Andres Osuna Finca los Diamantes Escuintla Finca Florida Aceituno Masaqua La Democracia Siquinala Finca Monterrey El Rodeo

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Page 1: Lahar Hazards of Fuego Volcano, Guatemala · from Fuego volcano. During any single rainfall event or earthquake, some drainages may be affected by slope failures and lahars, while

This map is preliminary and has not been reviewed for conformity with U.S.Geological Survey editorial standards or with the North AmericanStratigraphic Code. Any use of trade, product, or firm names is fordescriptive purposes only and does not imply endorsement by the U.S.Government.

Location Map

Guatemala

Base maps from Guatemala 1:50,000 scale series; Chimaltenango quadrangle,(2059 IV); Ciudad de Guatemala quadrangle, (2059 I); Alotenango quadrangle,(2059 III); Amatitlan quadrangle, (2059II) digital data courtesy of InstitutoGeorafico Nacional, Guatemala. Escuintla; 1985 (2058 IV); Guanagazapa1982 (2058 I) from best available sources. Digital Bases Maps from TitanAverstar, Inc. Universal Transverse Mercator projection, Zone 15,Horizontal Datum North American 1927, Vertical Datum Mean Sea Level,Spheroid Clarke 1866.

2001

J.W. Vallance, S.P. Schilling, O. Matias, W.I. Rose, and M.M. Howell

Area that could be inundated by a lahar having a volume of 1 millioncubic meters. Highest probability.

Area that could be inundated by a lahar having a volume of 2 millioncubic meters.

Area that could be inundated by a lahar having a volume of 4 millioncubic meters.

Area that could be inundated by a lahar having a volume of 8 millioncubic meters.

Area that could be inundated by a lahar having a volume of 16 millioncubic meters. Lowest probability.

Areas that could be affected by slope failures, avalanches, and laharsfrom Fuego volcano. During any single rainfall event or earthquake, somedrainages may be affected by slope failures and lahars, while others may becompletely unaffected. Debris avalanches and lahars originate within theproximal hazard zone, but are likely to move farther down stream beyond theflanks of the volcano and beyond the limit of this zone.

Channels that head on Fuego volcano are subject to lahars generated bydebris avalanches, torrential rains, earthquakes. Distal hazard zonesare subdivided into five zones on the basis of a range of hypotheticallahar volumes [4].

Other areas that could be inundated by lahars and floods, or beaffected by aggradation and channel changes.

Lahar Hazards of Fuego Volcano, Guatemala

NOTE: Although the map shows sharp boundaries for hazard zones, the degreeof hazard does not change abruptly at these boundaries. Rather, the hazarddecreases gradually as distance from the volcano increases (small volumeevents are more common than large volume events). In addition, for lahars,the hazard decreases rapidly as elevation above the valley floor increases.Areas immediately beyond outer hazard zones should not be regarded ashazard−free, because the boundaries of hazard zones can be located onlyapproximately, especially in areas of low relief. Many uncertainties aboutthe source, size, and mobility of future events preclude locating theboundaries of zero−hazard zones precisely.

Numerals in brackets refer to end notes in the report.

Carretera 2

Alotenango

Car

rete

ra14

Guadelupe

Finca SanAndres Osuna

Finca los Diamantes

Escuintla

Finca FloridaAceituno

Masaqua