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ISNS 4359
EARTHQUAKES AND VOLCANOES
Spring 2005
Steve Bergman, Instructor
Lecture 24. Beneficial Aspects of Volcanoes & Magmatic Systems
Inspire Awe & Fascination; Immense Value to Economy & Culture; Provide soothing springs and fantastic views
Historic Preservatives Ash falls from large eruptions are the only natural catastrophe capable of simultaneously burying
and preserving intact a snapshot of past lives. Ethiopian Rift deposits preserve and provide chronology of early hominids
3.4-4.4 million years ago. Pompeii documents 79 AD Roman culture and society. Akrotiri, Thera preserves 1628 BC
Bronze-age Greek agricultural practices & diet.
Geothermal Resources (Relatively Clean & Nearly Renewable) Direct heat & Electric energy production
Modern usage started at Larderello Italy 1904, electrical power generated by natural steam discharge.
Clear Lake, CA (Geysers) is the world’s largest productive geothermal system (~1 GW, enough to power a city of 1 million
people) ~6% of CA electricity is geothermal, 10% of N NV. Currently ~8 GW electrical power (combined with direct heating
by geothermal water of ~12 GW; total 90,000 GWh Annual use) produced worldwide, mainly in USA, Iceland, Japan, New
Zealand, & Philippines/each with >5,000 GWh/yr). Snow Monkeys use hot springs to keep warm in Japan.
Four requirements for large-scale operation: Magmatic heat source (active volcano); hot water or steam (above heat
source); highly permeable rocks (to allow water flow); nearly impermeable cap rock (to maintain pressure). Hot, dry steam is
best; wet acidic steam corrodes pipes and makes development difficult; environmental impact & pollution problems.
Volcanic Ore Deposits-worth hundreds of billions of dollars, volcanoes and their bowels have yielded metals and gems
for industry and adornment. Ore deposits are unusually high concentrations of minerals or elements that can be
economically exploited. Primary deposits form directly from magmatic processes (diamonds from kimberlites and
lamproite volcanic vents, Pt, Ni, Cr in layered basaltic intrusions, rare metals and gems in pegmatite veins and dikes).
Secondary deposits are mainly hydrothermal, resulting from circulating water in the crust, such as Porphyry Copper &
Molybdenum, Epithermal (hot spring) Gold & Silver, Massive Sulfide (black smokers) Cu, Pb, Zn, Ag.
Commercial "Ore" contains as little as ~2 parts per million Au, ~7 parts per billion diamond.
Volcanic ash soils are the most nutrient-rich on earth- Agriculture, Coffee, Wine
Volcanic soils cover 1.5 million km2 (1% of world's land surface, supporting 10% of the world’s population),
but not everywhere-only where climate is suitable to break down the ash, making nutrients available (warm and moist).
They nourished early civilizations in the E African Rift, Italy, Greece, Turkey, and the Mayan and Inca civilizations in the
Andes. Weathering products of volcanic rocks create porous medium that retains moisture, and yield natural nutrients:
Phosphorus, Potassium, and many others.
Volcanic Industrial Materials –unique sets of physical properties (appearance, density, strength)
Volcanic building materials have shaped the course of western civilization. Romans (150 BC) discovered volcanic ash mixed
with lime formed superior cement (weather and water resistant and stronger-pozzuolana) compared with the gypsumbased cement used by the Egyptians to construct the Giza Pyramids. Pozzuolana was used for monumental buildings,
baths, aqueducts, roads, many of which still stand after 2 millennia.
Slightly welded tuffs (cave dwellings in N & S America, Turkey, Italy, Greece)
Welded Tuffs and Ignimbrites (building blocks, lightweight, easily cut, good insulator)
Basaltic Scoria (road metal, cinder blocks, barbecue cinder radiants)
Lava/trap rock (decorative, building material)
Rhyolite Ash & Pumice (abrasive, absorbent, toothpaste, household scrubbing compound)
Bentonite (altered ash) (pond sealant, drilling mud, kitty litter, facial crème, cheap ice-milk products)
Native Sulfur (Rubber manufacture)
Perlite (absorbent, gardening, lightweight concrete)
Obsidian (Prehistoric knives, spear tips, axes, arrow heads)
Volcanoes and Culture New Zealand Maori use steaming pools to cook food and launder clothes.
Source of religions & myths (Japan, Indonesia, Hawaii, Mt. Shasta).
Literature: Charlotte Albert (1795) Montalbert, George Bulwer-Lytton (1834) The Last Days of Pompeii, James
Fenimore Cooper (1847) The Crater, or Vulcan’s Peak, Jules Verne (1864) Journey to the Center of the Earth, Edison
Marshal (1925) The Sleeper of the Moonlit Ranges, Bernice I. Goodspeed (1945) Paricutin, Malcolm Lowry (1947)
Under the Volcano, Patrick Leigh Femor (1953) The Violins of Saint-Jacques, Shusaku Endo (1959) Volcano, Philip
Freund (1959) The Volcano God, Lin Carter (1976) The Volcano Ogre, Edwin Corley (1980) Genesis Rock, A.N. Wilson
(1985) Gentlemen in England, Patrick Chamoiseau (1992) Texaco, Susan Sontag (1992) The Volcano Lover, Bob
Shacochis (1993) Swimming in the Volcano.
Mary Shelly’s Frankenstein was motivated by the effects of the 1815 Tambora eruption; written while on holiday at Lake
Geneva during miserable, dreary weather resulting from global climate effects of the ash.
Art: (mainly Etna, Vesuvius, Fuji) Andy Warhol’s Vesuvius 1985, Roger Brown The First Continental Eruption 1980.
Literary “Art” Film: The Last Days of Pompeii (1897), Stromboli (1950), Volcano (1953), Crack in the World (1965),
Krakatoa East of Java (1969), When Time Ran Out (1980), Joe Versus the Volcano (1990), Dreams (Mount Fuji in Red &
Demons-1990), Dante’s Peak (1997), Volcano (1997), and hundreds of documentary-type science films.
Volcano Tourism- fascination of being close to nature’s immense power; great views, soothing waters.
USA & Canadian Parks and volcano observatories attract millions of visitors each year:
(HI: Kilauea, Haleakala; WA: Mt. Baker, Mt. Rainier, Mt. St. Helens; OR: Mt. Hood, Three Sisters, Newberry, Craters
of the Moon; CA: Mt. Shasta, Medicine Lake, Lassen Peak, Long Valley; WY: Yellowstone, NM: Bandelier; AK:
Wrangell, Katmai; BC: Garibaldi). Mediterranean (Vesuvius, Etna, Santorini, Stromboli, Vulcano, Lipari), Caribbean
(St. Vincent, St Lucia, Guadeloupe, Martinique), New Zealand (White Island, Rotorua, Taopo, Wairakei, Tongariro),
Japan (Bandai, Fuji, Hakone, Izu-Oshima, Sakurajima), Costa Rica (Poas, Arenal, Irazu), Indonesia (Krakatau,
Galunggung, Kelud, Merapi, Agung, Batur, Rinjani), Philippines (Taal, Pinatubo), Mexico (Paricutin, Popo), Guatemala
(Pacaya, Fuego), Galapagos, Canary Islands, Azores, E Africa, S America, France, Germany.
Offer Waterfalls, Hot Springs, Geysers, Spas, Climbing, Spelunking, Skiing, Black & Green Sand Beaches.
Some useful books for further reading: Volcanoes: Crucibles of Change (1997), by R.V. Fisher & G. Heiken,
Encyclopedia of Volcanoes (2000) edited by H. Sigurdsson; Volcanoes of Europe (2001) by A. Scarth & C. Tanguy