Logo link to homepage

Report on Tupungatito (Chile-Argentina) — October 1988

Bulletin of the Global Volcanism Network, vol. 13, no. 10 (October 1988)
Managing Editor: Lindsay McClelland.

Tupungatito (Chile-Argentina) Volcano-seismic trigger for 1987 debris flow disputed

Please cite this report as:

Global Volcanism Program, 1988. Report on Tupungatito (Chile-Argentina). In: McClelland, L. (ed.), Bulletin of the Global Volcanism Network, 13:10. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN198810-357010.

Volcano Profile |  Complete Bulletin


Tupungatito

Chile-Argentina

33.425°S, 69.797°W; summit elev. 5660 m

All times are local (unless otherwise noted)


The following is from Alfredo Eisenberg and M. Pardo. "González-Ferrán (13:6) attributed the 29 November 1987 debris flow to an increase in local shallow volcano-seismic activity that he said can be observed on our seismograms of 28, 29, and 30 November. The seismic network in central Chile did not record any activity of this kind during those days, nor the previous ones. It is also important to note that only one station is located within 40 km of Tupungatito volcano's main crater (figure 3 and table 1). Stations on the Argentine side of the Andes did not register any volcano-seismic activity either. We did record the debris fall, however, at 1033 on 29 November, with an equivalent local magnitude of 4.5. This event, as far as we can see from the records, was not preceded by a triggering earthquake."

see figure caption Figure 3. Seismicity in central Chile, 27-30 November 1987. Circles mark epicenters of located earthquakes (table 1), squares the position of seismological stations. The source of the debris flow is marked by a circled cross, and Tupungatito volcano by a star.

Table 1. Seismicity recorded in central Chile, 27-30 November 1987, by Univ of Chile seismograph stations. Magnitude mt corresponds to an estimation of mb from the total duration of the PEL station record.

Date Time Latitude Longitude Depth (km) Magnitude (mt)
27 Nov 1987 1038 33°31'S 72°14'W 50 4.3
27 Nov 1987 1130 33°07'S 71°39'W 18 4.1
28 Nov 1987 0916 33°44'S 72°32'W 10 4.1
28 Nov 1987 2153 33°18'S 70°30'W 75 3.7
29 Nov 1987 0214 34°12'S 70°14'W 00 3.7
29 Nov 1987 0332 33°53'S 72°02'W 20 4.5
29 Nov 1987 0807 33°06'S 71°53'W 27 4.4
30 Nov 1987 0010 32°43'S 71°24'W 5 4.0
30 Nov 1987 0637 33°18'S 71°34'W 23 4.2
30 Nov 1987 1055 34°53'S 70°46'W 109 4.3
30 Nov 1987 1325 32°00'S 71°30'W 28 4.1
30 Nov 1987 1510 32°12'S 71°42'W 28 4.1

Geologic Background. Tupungatito volcano, the northernmost historically active volcano of the central Chilean Andes, is located along the Chile-Argentina border about 90 km E of Santiago and immediately SW of the Pleistocene Tupungato volcano. Tupungatito consists of a group of 12 Holocene andesitic and basaltic andesite craters and a pyroclastic cone at the NW end of the 4-km-wide, Pleistocene dacitic Nevado Sin Nombre caldera, which is filled by glaciers at its southern end and is breached to the NW. Lava flows from the northernmost vent have traveled down the NW flank breach. Tupungatito has produced frequent mild explosive eruptions during the 19th and 20th centuries.

Information Contacts: A. Eisenberg and M. Pardo, Univ of Chile.