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					ISNS 4359 EARTHQUAKES AND VOLCANOES (E&V)                                                                     Spring 2005
Steve Bergman, Instructor
Lecture 3. History of Volcanology & Seismology: Myths, Legends, Science
Curious humans have long marveled at natural processes such as E & V, and speculated about their causes. The inaccessible
nature of the Earth's interior has led to wild speculation about its origins. Renaissance writers compared the Earth to a human
body with a circulatory system in which blood represented underground rivers. When bodily processes became unsettled,
sickness ensued, so when interior rivers and caverns were disturbed, E & V followed. Gas expansion has figured prominently in
the explanation of volcanoes because of its association with natural eruptions. Our knowledge of human evolution is intimately
linked with volcanic eruptions, as the oldest known fossils occur in volcanic deposits in Africa and Indonesia, eg., the 3.7 million
year old (Ma) Australopithecus hominid footprints in volcanic ash at Laetoli, & 1.7 Ma Homo habilis fossils at Olduvi Gorge,
both E. Africa. Volcanoes also provided the raw materials for 2.5 Ma stone tools and weapons used by early humans, and 7 th
century BC pozzolana cement using Greek and Italian ash. Volcanic eruptions may have played a role in the controlled use of
fire by 1.5 Ma Homo erectus (burnt clay Chesowanja, Kenya). Volcanic eruptions have inspired worship, myths, & legends.
Many primitive people believed volcanoes were inhabited by temperamental demons that could be appeased with human
sacrifice (eg., Mayans, Aztecs, Incas, Nicaraguans, Javanese, East Africans).
Science -System of Knowledge (patterns of Facts); figuring out how the universe works; search for explanations of natural
phenomena based on physical and logical principles; began ~600BC with the Greek Ionian School of Philosophy. Science
evolves and advances as new analytical methods are developed and new data are acquired. Scientific theories can never be
proved, only falsified. Science is testable and verifiable. Science is distinct from religion, which is based on faith and belief.
Scientific Method - Critical process of asking questions about the observable world, devising explanations, and tests of
alternatives to eliminate some. Myth -A belief or theory not based on fact or reality, often involving supernatural beings.

A Timeline of Relevant Ideas & Developments
Scientist                 Year       Hypothesis, Discovery, or Development
Thales of Milatus         ~580 BC    Water caused earthquakes (EQ) (Earth like a ship floating on the sea)
Anaximenes                ~550 BC    Falling rocks in Earth's interior caused EQ
Pythagoras of Samos       ~520 BC    Suggested Earth was a sphere (not flat) with a central fire
Anaxagoras                ~450 BC    Eruptions & EQ caused by great winds of ether inside the Earth
Empedocles                ~440 BC    Greek Corporeal Elements: Air, Fire, Water, Earth; Earth has a molten center
Plato                     ~380 BC    Subterranean river of fire, Pyriphlegathon, was the source of lava flows
Aristotle                 ~330 BC    EQ & volcanoes were related and caused by internal fire & wind
Eratosthenes              ~240 BC    Calculated 25,000 mi Earth circumference using noon shadows in Syene & Alexandria
Seneca                      62 AD    Combustion of coal, bitumen, Sulfur inside the Earth was a source of eruptions
Pliny the Younger           79 AD    First detailed recorded observations of Vesuvius eruption (from afar)
Chang Heng                 132 AD    Built Chinese Earthquake watercock, primitive seismometer
Avicenna (ibn Sina)      ~1000 AD    EQ caused mountain upheavals
Snorri Godi               1000 AD    Basaltic rocks in Iceland resulted from a lava flow
Albertus Magnus           ~1250      Mountain uplifts caused by EQ and released vapors from interior
Agricola (G. Bauer)       ~1550      EQ caused by reaction of central fire and water vapors
Konrad Gesner             ~1560      Columanar basalts precipitated from seawater (Neptunist)
Cardan                    ~1570      Fiery vapors charged with sulfur, nitre, & bitumen caused EQ
James Ussher              1650       Calculated earth formation on 23 Oct 4004 BC
Isaac Newton              1692       Speculated Earth interior heated by mineral fermentation
G.W. von Leibniz          1749       Proposed the earth’s interior was molten, the crust having formed by cooling
John Mitchell             1755       Observed Lisbon EQ, first to measure seismic velocity
Nicholas Desmarest        1763       Columnar basalts from Clermont, Auvergne were lavas (Plutonist/Vulcanist)
Abraham Werner            1790       Neptunist Leader; Ocean source of all rocks-Great Deluge Legend
Lord Cavendish            1798       Calculated Earth mass 6.6e21 tons & bulk density 5.5 gm/cc using Newton's Laws
John Playfair             1802       First to propose rocks melted at higher temperatures with increasing pressure
Charles Lyell             1830       EQ & volcanoes caused by heat escaping from the core
Robert Mallet             1851       EQ caused by sudden rupturing of the crust, releasing massive forces;
                                     used dynamite to measure elastic waves in surface rocks
George B. Airy            1855       Used isostasy to explain thick light crust floating on dense mantle
G.-A. Daubre              1866       Suggested Fe-Ni meteorites were similar to Earth's core
John Milne                1880       Installed first seismometer in Yokohama, Japan & elsewhere
Osmond Fisher             1881       Proposed convection currents within the Earth
Bunjiro Kuto          1891         First to propose movement along a fault as the cause, not the effect, of EQ
Lord Kelvin           1897         Proposed <100 Ma age of Earth based on heat flow
Andrija Mohorovicic   1909         Used seismic waves to recognize discontinuity at base of crust
Alfred Wegener        1912         Proposed continental drift theory and Pangea supercontinent
Joseph Barrell        1914         Defined Earth lithosphere (strong), asthenosphere (weak) and centrosphere
Arthur Holmes         1928         Decompression melting of peridotite caused by mantle convection
K. Wadati             1935         Defined dipping subduction zones based on EQ distribution
Inge Lehmn            1936         Produced evidence of the existence and nature of the core
Warren Carey          1950s        Presented Expanding Earth Alternative Hypothesis (rejected)
M. Ewing & B. Hazen 1953           Discovered Mid Atlantic Ridge-Great Global Rift
Harry Hess, F. Vine, 1960s         Proposed modern plate tectonic theory (verified)
D. Matthews, T. Wilson, et al.

Summary of “scientific” (natural philosophy) ideas
600 BC-500 AD: Ionian School & Classical Antiquity (Thales, Aristotle, Pythagorus, Plato, Aristotle)
EQ caused by subsurface water, air, falling rocks
Spherical Earth with molten interior
Volcanoes caused by interior fires, combustible coal, bitumen, and sulfur
Greek 4 Elements: Air, Fire, Water, Earth
Vesuvius 79 AD Pliny
Chinese attributed EQ to blocking of the subtle essence (qi)
500-1400 AD: Middle Ages (Magnus, Aristotle, Avicenna/ibn Sina)
EQ caused by dry vapors from the sun through earth’s intestines, some vapors are poisonous, causing the
plague and disease
Mountains caused by EQ and inflated by interior winds
EQ caused by large sea beast
Iceland basalts were once lavas
1400-1800: Early Modern Times (DaVinci, Agricola, Descartes, Steno, Hooke, Darwin, Humboldt, Hutton)
Incandescent Earth core as the cause of volcanic heat
Solid Earth Model
Neptunist (Werner) - basalts and granites precipitated from seawater (later disproved)
Plutonist (Mitchell) - igneous rocks crystallized from magma
1800-1900: Crust ‘floats’ on solid mantle; EQ & volcanoes caused by interior heat; rock descriptions.
1900-1950: Radioactive Heat; Moho; Continental Drift; Geosynclines, Lithosphere/Asthenosphere.
1950-present: Mid-Atlantic Ridge; Magnetic Stripes; Plate Tectonics; Hot spots/Mantle Plumes
Most organized religions-Natural disasters result from divine wrath.
Some Selected Myths & Legends
Native people in Kamchatka, Russia believed earthquakes occurred when a giant dog, Kozei, shook freshly fallen
snow from his coat. Early Chinese envisioned the Earth riding on the back of a giant ox, and Mongolians a giant
frog. Whenever the animal moved, the Earth shook and trembled.
Klamath Indian myths Llao, Chief of the Below World, located on Mt. Mazama (Crater Lake, OR) was locked in a
mighty battle with Skell, Chief of the Above World, located at Mt. Shasta (CA). Their battle waged for many years
while they threw gigantic stones and fire at each other and darkened the sky with ash, and finally ended when Llao
fell back into his underground world, leaving a huge collapsed crater which filled with water to form the deepest lake
in N America. This caldera is now known to have formed 6,900 years ago and was presumably observed by many
Native Americans.
                 th
Was Plato's (4 Century BC) Lost Continent of Atlantis in the Aegean? Yes The Bronze Age (1628 BC) eruption
of Thera, Greece (Santorini, largest in the Mediterranean in the last 10,000 years), (70 km N of Crete) produced a 6
km diameter caldera, destroying the island, and many tsunamis and floods. This eruption probably led to the decline
of the Minoan civilization, burying Akrotiri and other cities, and possibly was the origin of the lost continent of Atlantis,
and the seeds of many subsequent Hellenic gods and myths.
Greek & Roman Mythology Volcanoes are associated with Pluto, Perephone, Vulcan (unruly child of Jupiter and
Juno, lived with his forge inside the volcano on the tiny Aeolian island, Volcano), Typhon (first-born to Gaia -Mother
Earth and Zeus, was the largest monster with fire flashing from eyes and flaming rocks hurled from his mouth). Virgil
described Mt. Etna eruptions as the burning breath of the Titan, Enceladus, as he struggled to free himself from his
underground prison. Earthquakes and Volcanic activity were caused by stirrings of the Titans (giants imprisoned
within the Earth) and battles with Olympian gods). Zeus eventually hurled Mt. Etna at Typhon and imprisoned him,
his stirring causing earthquakes and eruptions. Neptune (aka Poseidon) was the Earthshaker. Jason and the
Argonauts returned to Greece with the golden fleece and were assaulted by Talos, a bronze giant who threw stones
at them (at Rhodes and Karpathos and the eruption of Thera with its ejected pumice). Greek Hephaistos (son of
Hera & Zeus, spouse-Aphrodite) was the Vulcan father of the monster Cacus. Hades of the Greeks and Hell of the
Christians represented eruptions, the eternal fire and brimstone of the Earth's interior, as punishment for a sinful life;
Mt. Etna was thought to be a gateway to Hell, going there termed "sailing to Sicily."
The Scandinavian god Loki was tied to a rock in a cave as punishment for killing his brother. A serpent would drip
poison on him, which was collected in a bowl by his sister. When she emptied the bowl, Loki would twist and turn to
avoid the poison, causing the Earth to shake.
Ancient inhabitants of India believed the Earth was held up by one of seven serpents that caused trembling when
the Earth was switched. Others that Earth was held up by four elephants that stood on the back of a giant turtle, in
turn on the back of a cobra.
The Japanese believe nature centers around Mt. Fuji, with its majestic symmetry. Instead of viewing volcanoes as
demonic, they view Mt. Fuji and other volcanoes as collaborating friendly spirits with supernatural powers. The Oni
monster is a horned red giant that hurled rocks out of volcanoes. Ancient Japanese believed a giant catfish,
Namazu, which was controlled by a god. When the god turned away, Namazu would flop around and cause
earthquakes. A catfish was selected because they exhibit unusual behavior prior to earthquakes.
Hawaiians offer flowers, candy, fruit, cloth, and gin to Madame Pele, who carried a magic digging stick that opened
up craters wherever she dug. When she was angered, she stamps her foot, causing earthquakes and rivers of lavas
to destroy those who displeased her, and killing innocent victims. Princess Ruth Keelikoani was carried near the
edge of an advancing lava flow in August 1881 where she chanted incantations, scattered red silk scarves and
sprinkled brandy on the lavas. The lava stopped short of a nearby village the next day.
New Zealand Maori people believe Taranaki (Mt. Egmont) once stood 125 km east between Tongariro and Ruapehu
but stormed off, carving the Whanganui River valley in anger, after observing Tongariro seduce Ruapehu, stopping
as the sun set to look back at his wife Ruapehu, and continues to do so today. The Phantom canoe story of Lake
Rotorua, with its hot springs and steaming pools, dates to 1886, when 13 people paddling a large war canoe were
lost during the eruption of Tarawera.
Aztecs of Mexico named volcanoes after their gods, such as Popocateptl (Smoking Mountain) and Iztacchiuatl
(Sleeping Woman). When Popo was victoriously returning from a war battle, his enemies sent word ahead to Iztac
that he had been killed, and the princess died of grief. Popo then built two mountains, on one he placed Iztac, and on
the other he stands eternally holding her funeral torch.

Common Themes: Immense Power, linked with supernaturally large animals
Volcanoes, Earthquakes, Faults, and Tsunami are well documented in the Bible:
Exodus (13, 19, 20) & Deuteronomy (4:11), Description of volcanic eruption on Mt. Sinai (Precambrian granite),
although 2000 BC volcanism is known at Jebel Druse, Syria and elsewhere in N Israel.
Job (9:5,6), Amos (1:1), & Zechariah (14:5) Hazor in Galilee was partially destroyed by an EQ at 760BC.
Amos (9:6), (Joshua 3:14-17; 4:18)…"when the walls came tumbling down," was possibly associated with an
earthquake at 1500 BC. Jerico lies on the Dead Sea fault (1-2 cm/yr), which averages one M6.5-7 earthquake
every century over the last 3 millennia. Several later EQ (1267, 1906, & 1927) have caused landslides and the
River banks to cave in, which temporarily dammed the Jordan River, possibly permitting passage of the
Isrealites. Destruction of the cities of Sodom and Gomorrah (Genesis 19:17), two cities near the Dead Sea
coast, could have accompanied seismic and volcanic activity, which are known to have occurred at 1900-2400
BC in the region.

				
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