Geological Survey Circular 318 Eruption of Trident Volcano — Katmai National Monument, Alaska — February-June, 1953

Coincident activity of other vents during this eruption includes the February 17 ash explosions of Mount Martin or Mount Mageik or both and the southeast Trident fumarole mentioned above.

The Anchorage News of March 3 quotes a Mrs. William Tauscher of Anchor Point (Kenai Peninsula) as saying that Iliamna Volcano "poured forth with a huge mushroom-shaped billow of inky black smoke at 7:30 a. m. Sunday (March 1)." Two distinct sources of eruption are claimed to have been sighted, one on top and one off to the side of the mountain. Lt. James Ingram USN flying about 50-75 miles south-southeast of the Iliamna area on March 3 gives a partial confirmation of this story. He sighted a cloud column rising from the mountain but at that distance could not discern whether it was smoke or steam. The writer visited the Iliamna area aboard naval aircraft on March 5 and 6. On these dates only a small fumarole near the top and on the east side of Iliamna was active, sending up a column of steam several hundred feet high. No ash was visible on the glaciers blanketing the mountain.

On March 2 Richard McDonald, U. S. Geological Survey seismologist stationed at Adak, rode a Navy plane from Kodiak to Adak and back. He reported steam rising from Paviof, Shishaldin, Makushin, and a small cone within Okmok Caldera on this day. Probably other volcanoes elsewhere along the chain were also steaming. This is the normal condition throughout the tectonically and volcanically active Aleutian arc and should not be interpreted as a reaction related to the Trident eruption. The explosions of Mount Martin or Mount Mageik on February 17 (and, possibly the late afternoon of February 16) appear to have been related to the Trident eruption.

Lt. Dee L. Leland, USN, who has probably observed as much of the early phases of the Trident eruption as anyone, reported that on the flight on March 11 he noticed a marked coincidence in timing of the Trident explosions with the much smaller steam puffs from Mageik crater. Whether Lt. Leland was observing coincidental activity or connected events of genetic significance is not known.

Since February 17 both Mount Martin and Mount Mageik have shown no more activity than their normal puffing of steam. Other fumarolic areas in the Katmai National Monument that are now active include the "hotspot" on the southeast flank of Trident, Katmai crater (its lake, though locally containing rafts of ice, was unfrozen while, nearby, the unnamed crater lake adjacent to Kaguyak Bay was frozen over), a line of large fumaroles and "hot" ground extending along the bench below the west side of Baked Mountain for about 2 miles (these were observed by Emil Meitzner, U. S. Geological Survey, from the middle Valley of Ten Thousand Smokes in June 1852), a large area of small fumaroles and hot ground from Novarupta to Broken Mountain, a few mud-pots along the "Greased Ridge" between Baked and Broken Mountains, a single large fumarole in the canyon of the River Lethe at the north end of the Buttress Range near the Three Forks area, and, possibly, a small "hotspot" (no steam noticed) within the inner crater ring of Knife Peak. A large fumarole, reportedly by (1952) on the northwest slope of Katmai, could not be seen. As far as can be determined it is likely that all but the southeast Trident fumarole were active before and have continued unchanged throughout the Trident eruption. Probably other small fumaroles exist, especially in the upper Valley of Ten Thousand Smokes, but were not noticed from the plane.

The recorded eruptive history of the Katmai National Monument area begins with the eruption on June 1912 that formed the Valley of Ten Thousand Smokes, eviscerated Mount Katmai, and deposited over a foot of ash on parts of Kodiak Island. This is without doubt the largest recorded Aleutian-Alaskan eruption although several other recorded eruptions in other parts of the world were more violent more destructive, or erupted greater quantities of rock material. Furthermore geologic evidence indicates that many other eruptions of greater magnitude than the Katmai disturbance in 1912 have occurred during prehistoric times throughout the Aleutian island arc. Since 1912 Katmai, Mageik, Mount Martin, and Novarupta have been steaming almost constantly and giving vent to minor ash eruptions sporadically (Coats, table 2; and personal communication with Howard A. Powers, U. S. Geological Survey). Mageik is last reported to have erupted in 1951 (Kodiak Mirror, Feb. 21, 1953, p. 1). U. S. Air Force aerial photographs taken in July 1951, show a linear grouping of fumaroles on the southwest flank of Trident Volcano near the site of the present vent.