Logo link to homepage

Report on Mayon (Philippines) — February 1985

Scientific Event Alert Network Bulletin, vol. 10, no. 2 (February 1985)
Managing Editor: Lindsay McClelland.

Mayon (Philippines) Eruption clouds from 23 September seen on satellite images

Please cite this report as:

Global Volcanism Program, 1985. Report on Mayon (Philippines). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 10:2. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198502-273030.

Volcano Profile |  Complete Bulletin


Mayon

Philippines

13.257°N, 123.685°E; summit elev. 2462 m

All times are local (unless otherwise noted)


Yosihiro Sawada observed a series of plumes from the September 1984 eruption of Mayon (table 1) on images from the GMS satellite. Problems with the scanning system of the GMS limited images to every 6 hours during the spring and summer, and at times prevented data returns from its southern zone of coverage.

Table 1. Series of plumes from the September 1984 eruption of Mayon observed on images from the GMS satellite. Plume lengths and widths were measured from images rather than digital data. Courtesy of Yosihiro Sawada.

Date Hour Density Width (km) Length (km) Movement Direction
09 Sep 1984 ?14 diffuse 30 60 W
11 Sep 1984 ?14 diffuse 50 70 WSW
12 Sep 1984 ?14 diffuse 20 60 W
13 Sep 1984 ?00 diffuse 70 110 SW
13 Sep 1984 08 diffuse 20 70 SW
13 Sep 1984 14 diffuse 20 90 SW
15 Sep 1984 08 diffuse 20 70 NW
15 Sep 1984 14 diffuse 30 40 NW
16 Sep 1984 08 diffuse 30 70 W
16 Sep 1984 14 diffuse 30 40 W
16 Sep 1984 20 diffuse 30 80 W
17 Sep 1984 02 diffuse 30 40 W
18 Sep 1984 02 diffuse 30 40 SW
18 Sep 1984 08 diffuse 40 50 W
18 Sep 1984 14 diffuse 30 60 W
18 Sep 1984 20 diffuse 30 60 W
19 Sep 1984 02 diffuse 30 60 W
20 Sep 1984 02 diffuse 40 70 NW
22 Sep 1984 02 diffuse 40 60 W
23 Sep 1984 08 dense 40 120 W
23 Sep 1984 14 dense 80 260 W
23 Sep 1984 20 dense 40 140 W
24 Sep 1984 02 dense 40 220 W
24 Sep 1984 08 dense 80 190 W
24 Sep 1984 14 dense 70 100 SW
24 Sep 1984 20 diffuse 70 80 SW
25 Sep 1984 02 diffuse 40 40 SW
25 Sep 1984 08 diffuse 40 80 W
25 Sep 1984 14 diffuse 40 60 NW

Eruption clouds from Mayon's intense activity 23-24 September appeared much larger and denser on satellite imagery than those from the early- to mid-September activity. A moderate plume on 23 September at 0800 had grown much larger 6 hours later (figure 3, left and right) and plumes remained large and dense through 1400 the next day. Declining activity remained visible until 26 September at 1400.

Figure (see Caption) Figure 3. GMS infrared satellite images with arrows pointing to eruption clouds from Mayon, 23 September 1984 at 0800 (left) and 1400 (right). Land areas are outlined with fine white lines. Courtesy of Yosihiro Sawada.

Further Reference. Sawada, Y., 1987, Study on analysis of volcanic eruption cloud image data obtained by the Geostationary meteorological Satellite (GMS): Technical Reports of the Meteorological Research institute (Japan), no. 22, 335 p.

Geologic Background. Beautifully symmetrical Mayon, which rises above the Albay Gulf NW of Legazpi City, is the Philippines' most active volcano. The structurally simple edifice has steep upper slopes averaging 35-40 degrees that are capped by a small summit crater. Historical eruptions date back to 1616 and range from Strombolian to basaltic Plinian, with cyclical activity beginning with basaltic eruptions, followed by longer term andesitic lava flows. Eruptions occur predominately from the central conduit and have also produced lava flows that travel far down the flanks. Pyroclastic flows and mudflows have commonly swept down many of the approximately 40 ravines that radiate from the summit and have often devastated populated lowland areas. A violent eruption in 1814 killed more than 1,200 people and devastated several towns.

Information Contacts: Y. Sawada, Meteorological Research Institute, Tsukuba, Japan.