A Volcano Within a Volcano: Portrait of the Taal Volcano
The News Story
After remaining relatively quiet for several decades, Mt. Taal in the Phililppines has come back to life (January 2020), causing massive evacuations and huge travel delays because of airborne ash. Beginning in January, huge ash clouds began pouring out of the mountain top with some of the ash even causing major problems at the Manila airport.
Along with the ash clouds, there has been magma shooting out of the cone, numerous earthquakes and abundant lightning above the volcano summit. All of this has created major concern that another major eruption is likely to occur in the near future.
The exact location of the Taal Volcano might need a bit of clarification. First of all, it is situated on Luzon, the northernmost island of the Philippines. Luzon is about 420 miles long and 140 miles wide. Lake Taal, which covers 90 square miles, can be found about 30 miles south of Manila on the Batanga Peninsula. Lake Taal is an ancient caldera, created by a supervolcano, a long time ago.
In the center of Lake Taal is Volcano Island. It is a small island (9 sq. mi.) that contains a very active volcano called Taal. Although small in size, Taal (or sometimes Mt. Taal) is one of the most geologically active places on the planet.
P.S. In the Tagalog language, the word, Taal, means native, natural or original.
Contrary to popular belief, supervolcano is an actual scientific term, referring to the largest sized volcanoes on our planet. Over the years, geologists have developed a straightforward method for calibrating volcanic eruptions, both past and present. To do this they simply calculate the volume of erupted material that has been ejected from the mouth of the volcano. The measurement is done in cubic kilometers or km3.
Next, the data is quantified into a scale ranging from 1 to 8. This scale is called the VEI or Volcano Explosivity Index. Volcanoes, which emit at least 1,000 km3 of volcanic material (called tephra by scientists) are classified as supervolcanoes. The first eruption at Taal occurred some 500,000 years ago. Today, this event is categorized as a supervolcano.
Aerial View of Lake Taal in the Philippines
After a volcano completes its eruption cycle, it often leaves a giant crater at the top of the mountain. Over time, the floor of the giant valley may collapse, creating an even larger bowl shaped depression. The scientific word for this geologic landform is caldera. Throughout the world, most calderas remain dry, but there are a few, like the one at Taal that will fill up with water to form a large lake. Other famous volcanic lakes, created in this manner, would include Lake Taupo in New Zealand, Lake Tobo in Indonesia and Crater Lake in the United States. Among all these volcanic lakes, Taal is the most active, today.
Taal Volcano Before 1911
History of the Taal Volcano
The Taal volcano sits on the island of Luzon, just a mere 31 miles from the the Philippine capital of Manila. The volcano is part of the infamous Ring of Fire that rims the Pacific Ocean. In the case of Mt. Taal, its volcanic activity is created by the subduction of the Eurasian Plate underneath the Philippine Mobile Belt. This process dates back at least 500,000 years.
Today the small volcanic island, called Volcano Island that sits in the middle of Lake Taal is one of the most geologically active places on the planet. In the last five hundred years, the volcano has erupted 33 times. Several of these eruptions have been fatal with the death toll often exceeding 1,000. The last major eruption occurred in 1977, though the volcano has been in a continual state of unrest since 1991.
Peaceful Wizard Island
At first glance, Crater Lake in Oregon (USA) shares many similarities with the Taal volcano in the Philippines. For starters it has a small, volcanic island in a large lake, which was created by a large volcanic eruption, a long time ago. The major difference is that the island has not seen any volcanic activity in about five thousand years. Despite this long period of inactivity, Crater Lake is still considered an active volcano.The reason being is that in geological time, five thousand years is next to nothing. As a result, the place will retain its classification for thousands of years to come, even though future geological activity is doubtful.
© 2020 Harry Nielsen