Volcanic fumaroles can offer scientists useful insights into events occurring within the Earth. These structures frequently occur in association with volcanic activity. Exploring the “anatomy” of a fumarole may present significant dangers, yet the process often provides a way to monitor important environmental changes.
What are volcanic fumaroles?
Volcanic vents develop when surface layers of the planet open to emit material from the interior. Several types of fractures occur—and fumaroles signify one very specific form. Fumaroles are spontaneous fissures in the crust which emit volcanic gasses and vapors.
They often occur near an active volcano, but may appear elsewhere, too. Sometimes fumaroles form along the surface of a lava flow, for instance. Geologists sometimes locate fumaroles forming chambers or pockets directly beneath the surface; these spots may weaken and break open on occasion, releasing toxic gasses.
Why volcanic fumaroles may be useful
The name “fumaroles” provides a descriptive memory device for the phenomenon of gasses and vapors escaping into the atmosphere during periods of volcanic activity. In Latin, the word “fumus” referred to smoke or fumes.
Volcanic fumaroles may cover only a short area—or they may extend across long fissures. Sometimes these vents close over relatively quickly after only a few weeks or months; on other occasions, a fumaroles may continue emitting gasses for a period of years, or even for centuries at a time. Temperatures can fluctuate within a fumarole as well.
Volcanologists, the geophysicists who specialize in the study of volcanic phenomena, may monitor a volcanic fumarole closely to check for changes in the local area. By determining the temperature, the depth and possible expansion or contraction in the dimensions of a fissure, for example, scientists may better appreciate ongoing processes occurring beneath the surface.
The types of gasses and vapors, and the estimated quantity of emissions, may also offer helpful data. In some locations, deposits of sulfur or other minerals develop around the edges of the fissure. Collecting and testing samples of this material (if possible) may offer useful details about ongoing geologic activity.
The importance of a fumerole
Since cracks deep within the earth sometimes release gasses through fumeroles, monitoring for structural changes can sometimes provide clues about shifting magma flows within a volcanic edifice. This process over the course of time may offer some information about whether or not geologic activity is “heating up” or quieting down. It can assist in the construction of computer models of a location.
For example, scientists studying volcanic activity off the coast of New Zealand observed that a particular vent called the Rudolf Vent grew from a fumarole during a series of ash eruptions which occurred in 1968. By the following year, the fissure had extended to reach 45 meters in diameter and an estimated depth of 120 meters. The activity around the fumaroles indicated that significant events might be occurring far beneath the surface.
Fumaroles may present as a potentially very dangerous environment. A vent may expand suddenly, causing a collapse on the surface, releasing highly toxic gasses into the vicinity. Additionally, high temperatures can pose a risk to people working nearby.
Studying the structural “anatomy” of a volcanic fumerole provides one more tool for scientists seeking to understand ongoing transformations within regions of volcanic activity. The phenomena has become a valuable source of information for volcanologists and other geophysicists.