Volcano Diaries

Imelda and Edwin at Taal Volcano in the Philippines, with the cinder cone "Binintiang Malaki"
and Taal Lake in the background. Photo courtesy Dr. Jett Aguilar.
We are fascinated by volcanoes. We admire them for their sheer beauty and majesty, but at the same time we are awed by their brute force and oftentimes lethal fury. Volcanoes offer a glimpse — a window — into the Earth’s molten interior. They provide some of the clearest physical evidence of just how active and dynamic our home planet is.
Volcanoes are like a double-edged sword: they are capable of producing conditions conducive to life, such as creating new land and enriching the soil, but at the same time they can cause widespread death and destruction due to lava and pyroclastic flows, ash fall, and lahars (mudflows).

Diagram courtesy U.S. Geological Survey.
The Philippines, where we were raised and educated, is a perfect natural geological laboratory for studying volcanoes. The country, which sits along the so-called “Pacific Ring of Fire” where volcanoes — and earthquakes — are most prevalent, has more than 20 active volcanoes, many of them considered deadly. The list includes Pinatubo in Zambales, Taal in Batangas, Mayon in Albay, Bulusan in Sorsogon, Hibok-Hibok in Camiguin, Kanlaon in Negros Oriental, and Ragang in Cotabato.
The following are some of our experiences exploring these interesting geologic landforms.
1991: A Trek to Ground Zero

Mount Pinatubo's first major eruption, on June 12,
1991, as viewed from Clark Air Base, Pampanga.
Photo courtesy U.S. Geological Survey.
On our way back to the Philippines after successfully observing the July 1991 total solar eclipse in Baja California, Mexico, we hooked up with then-Sky & Telescope associate editor Stephen James O’Meara at the Los Angeles International Airport. A well-known volcano enthusiast and a dear family friend, Steve wanted to cover the aftermath of Pinatubo’s cataclysmic eruption for an article he was writing for Science Probe! magazine.
Steve and his wife, Donna, have been traveling all over the world chasing volcanic eruptions — to Kilauea and Mauna Loa in Hawaii; Mount St. Helens in Washington; Etna, Stromboli, Vulcano, and Vesuvius in Italy; Arenal in Costa Rica; and Pacaya in Guatemala, to name a few. In 1987, Steve visited the Philippines to see Taal and Mayon volcanoes.
Since we share a common passion for volcanoes, and the fact that we missed witnessing the actual eruption of Pinatubo in June 1991 because we were in the U.S. at the time, we agreed to accompany Steve to the site.
Riding in a government van from Manila, we headed northwest to the province of Pampanga. We saw firsthand the widespread devastation brought about by Pinatubo’s wrath — entire towns buried in thick layers of gray, concrete-like volcanic ash; fertile farmlands turned into barren wastelands, and long lines of evacuees fleeing with whatever meager belongings they had left. It was such a heartbreaking sight!
We proceeded to Clark Air Base and met with volcanologists from the Philippine Institute of Volcanology and Seismology (PHIVOLCS) at the base’s command center. We then drove slowly around the now-deserted U.S. military base. We saw roofs and trees that collapsed under the weight of rain-saturated ash, brand-new cars in a dealership that were abandoned in the lot, and, in the officers’ housing complex, there were washing machines and dryers left behind in the driveway by fleeing homeowners. It was an eerie scene — much like in the aftermath of a nuclear holocaust where everyone simply vanished without a trace.



Imelda and Edwin took these photos inside Clark Air Base in Pampanga
about a month after Pinatubo's eruption. They show trees and hangars
that collapsed under the weight of volcanic ash, as well as abandoned
residences in the officers' housing complex.
Our group then proceeded to the Sacobia River, which ran adjacent to the base’s northern perimeter. It was an incredible sight: the riverbanks were filled with several-stories-high pyroclastic materials that had flowed down the slopes of Pinatubo into the major rivers that drain the watershed, including the Sacobia. The U.S. Geological Survey estimated that Pinatubo deposited as much as 5 to 7 cubic kilometers of pyroclastic debris onto the volcano’s slopes and surrounding towns and agricultural lands.



Imelda and Edwin photographed these pyroclastic deposits along the
Sacobia River, which runs adjacent to Clark Air Base. Note the thickness
of the pyroclastic layers compared to the size of the people in our group.
Nearly a month had passed since the eruption, but the pyroclastic layers along the Sacobia were still white-hot. We watched in astonishment as huge chunks of it would fall in mini avalanches into the river, and as soon as they touched the water, they produced immense, hissing plumes of white, sulfur-smelling clouds of steam. The river itself had become a channel for lahar, the thick, dense brown mudflow that dragged anything and everything along its path — boulders, trees, houses, roads, bridges, cars, farm animals, and people.


Steam clouds produced by hot pyroclastic materials coming in contact
with water, as photographed by Edwin and Imelda.
The following day, back in Manila, Steve chartered a four-seater plane for an aerial survey of Pinatubo. Flying over Pampanga at more than 5,000 feet, we looked out the window and saw the full extent of the devastation — the lahar had altered the course of rivers, washed away many of the towns' infrastructure, and flooded huge swaths of fields that used to grow rice, watermelons and cantaloupes. The cost of the destruction was staggering.

Aerial view of the devastation caused by the lahar
(mudflow) from Pinatubo. Photo courtesy Stephen
James O'Meara.
As we got closer to Pinatubo, nestled high in Zambales’s Cordillera range, we saw trees lining the slopes that were felled in a radial pattern by the force of the volcano’s blast. (The scene reminded us of photos from the Tunguska explosion in Siberia in 1908 and the eruption of Mount St. Helens in Washington in 1980.) Unfortunately, the summit of Pinatubo was shrouded in thick cumulus clouds at the time, and our pilot decided it was too risky to try to get any closer. So we just circled the base of the volcano, taking photos and video before heading back to Manila.
Pinatubo’s eruption was truly an awesome display of Nature’s power and fury, but we hope we don’t get to see one happening near highly populated areas ever again.


Aerial views of Pinatubo's summit crater. The top picture, taken on
August 1, 1991, shows a small eruption in progress. In the bottom
photo, shot on September 10 that year, a lake could be seen starting
to form in the volcano's caldera. Note the fumaroles (steam vents) in
the background. Photos courtesy U.S. Geological Survey.
Taal Volcano Photos

Imelda poses next to a fumarole (steam vent) along the
trail leading up to the Main Crater. This was her third climb
of Taal Volcano.

Imelda standing on the crater's rim, enjoying the spectacular view of
Taal's Crater Lake.

This photo shows the steep walls of the Main Crater.

A close-up view of the lake's boiling-hot, blue-green waters.

With members of the Astronomical League of the Philippines at the
summit of Taal's Main Crater. Photo courtesy Dr. Jett Aguilar.

Hiking across the jagged lava field created by the 1965 eruption of
Mount Tabaro.

A close-up view of Mount Tabaro.

Crossing Taal Lake.

Back safely at the PHIVOLCS station after a full-day hike of Taal Volcano.
Photo courtesy Dr. Jett Aguilar.
Mayon Volcano Photos

Mayon Volcano's perfect cone. Photo courtesy Stephen James O'Meara.

Steve O'Meara and Imelda near the foothills of Mayon Volcano. Photo
courtesy Stephen James O'Meara.