Merapi is a classically
conical, young composite volcano, looming almost 3 km high behind the important
city of Yogyakarta, in central Java. This is one of the most sacred
volcanoes of Indonesia, and is respected as a home of Gods and Goddesses.
Those gods have been generous, creating some ofJava’s most fertile land around the flanks of the volcano, but have also
been wrathful, killing several thousand people on these flanks over the past
century.
The major Merapi eruption of October -
November, 2010 has now quieted down, but new hazards have developed, and
the volcanic risks to people living on this majestic volcano's flanks
have diminished, and changed, but remain deadly.
Over 350 people were killed by pyroclastic flows during this eruption, and several hundred thousand people have been evacuated - most of these people have lost their homes and livelihoods because of the eruption. Volcanic ash has blanketed several hundred square km of land on and around the volcano. Where thin, this new ash will bring new fertility to rice paddies - but where thick on Merapi's flanks new hazards from volcanic mudflows have been created - and it is feared that heavy rains over the next months will bring more death and destruction - downstream from the areas impacted by pyroclastic flows over the past month....
TUNGURAHUA VOLCANO
Tungurahua is a beautiful composite volcano in the central Andes 140 km south of Quito, Ecuador. The volcano has been episodically erupting since 1999, with activity especially vigorous this year, and is currently in eruption, with strombolian blasts beginning a week ago, and ash clouds rising about 3 km above its 5,000 m-high, snow-covered summit. The small tourist destination city of Baños lies about 10 km from the summit in a drainage subject to floods and lahars, but has not required evacuations yet this year.
Volcano Thought of the Month
It is becoming
increasingly clear that the magma reservoirs underlying the world’s active
volcanoes are, for the most part, in a delicate state of gravitational equilibrium
with enclosing rocks, and that many factors can contribute to their destabilization
and to subsequent eruptive activity.Eruption
“triggers” are mostly related to processes that increase the buoyancy and
mobility of magma bodies underlying volcanoes, and in many cases where long
inactive volcanoes erupt, the renewed activity has been shown to be related to
the ascent of new basaltic magma from below (as at Mt. Pinatubo in 1991).
VOLCANOES - Global Perspectives
About the book: Volcanoes are essential elements in the delicate global balance of elemental forces that govern both the dynamic evolution of the Earth and the nature of Life itself. Without volcanic activity, life as we know it would not exist on our planet. Although beautiful to behold, volcanoes are also potentially destructive, and understanding their nature is critical to prevent major loss of life in the future. VOLCANOES is available in both hard- and softbound editions.