IMPACTS Part4

SCIENCE 100Earthquakes, Tsunamis, and Volcanoes as Phenomenaof Tectonic Plate MotionRoy A. Watlington, UVI: 

SCIENCE 100 Earthquakes, Tsunamis, and Volcanoes as Phenomena of Tectonic Plate Motion Roy A. Watlington, UVI Bob Senior Photo,1997

Slide2: 

USGS

Slide3: 

crust Inner core Outer core mantle

Slide4: 

Illustration of “Continental drift ”

Slide6: 

Globally, locations of most frequent, most intense earthquakes coincide with plate boundaries.

Slide7: 

The Caribbean Plate Moves East  Relative to the North & South American Plates

Slide8: 

The Caribbean Plate and Its Structures

Slide9: 

Caribbean plate motion is a source of Caribbean E A R T H Q A K E S !!

Slide10: 

Question: Can you sketch the approximate shape and boundaries of the Caribbean Tectonic Plate?

Slide11: 

As one plate subducts another, the rubbing of the plates generate earthquakes. Seismogenic zone

Slide12: 

In the United States, the most infamous fault is the San Andreas Fault.

Slide13: 

The 1867 Earth-quake in the Danish West Indies. Church steeple falls in Frederiksted.

Sources of Earthquakes in the Puerto Rico-Virgin islands Region: 

Sources of Earthquakes in the Puerto Rico-Virgin islands Region The Puerto Rico Trench - 8.0 on the Richter Scale The Muertos Trench - 7.5 on the Richter Scale Anegada Passage - 7.25-7.5 on the Richter Scale

Slide15: 

How the Earth’s Core affects the travel of seismic waves. (After C.F. Richter (1985) Elementary Seismology, W.H. Freeman) Mantle INNER CORE S-wave shadow zone P-wave shadow zone

Slide16: 

P-wave S-wave Compressions Dilations One wavelength P-waves compared to S-waves

Slide17: 

Zones of compression Bang on this end Zones of dilation (rarefaction) How a P-wave propagates

Slide18: 

Disturb this end UP and DOWN One wavelength Direction of Propagation How the S-wave propagates

Slide19: 

Honolulu Tokyo Manila Scale The Pacific Ocean Finding the Epicenters of Earthquakes

The Richter Scale forEarthquake Magnitude : 

The Richter Scale for Earthquake Magnitude On this scale the weakest earthquake has a rating of about 2. The strongest recorded earthquakes were about 8.9. The Antigua earthquake of 1974 was about 5.2. The 1867 Danish West Indies earthquake that caused the tsunami was (approx) 7.25-7.5

The Richter Scale (continued): 

The Richter Scale (continued) The Richter Scale is an expression of earthquake energy. A magnitude 3 earthquake has 30 times more energy than a magnitude 2 earthquake. QUESTION: If a magnitude 2 earthquake releases 5 units of energy, how many units of energy does a magnitude 7 earthquake release ?

The Richter Scale (Answer to the question): 

The Richter Scale (Answer to the question) 3 4 5 6 7 [ 30 x 30 x 30 x 30 x 30 ] x 5 units = 121,500,000 units (Multiply by 30 for each magnitude step)

The Modified Mercalli Index for Earthquake Intensity : 

The Modified Mercalli Index for Earthquake Intensity I - Not usually felt IV - Felt by many indoors, outdoors by few V - Felt by everyone, dishes broken, plaster cracked VII - Everyone runs outdoors; damage to buildings slight IX - Considerable damage; underground pipes severed XI - Few masonry structures survive, bridges destroyed, ground waves visible, broad fissures in the ground. XII - !!!!!!!

Slide24: 

T S U N A M I !

Slide25: 

The Royal Mail Packet, LaPlata, being taken by the tsunami wave, November 18, 1867

The Hawaiian Island of Hilo, 1946: 

The Hawaiian Island of Hilo, 1946

Slide27: 

Hilo again hit by tsunami - in 1960

Slide28: 

The Scotch Cap Lighthouse before 1946

Slide29: 

Tsunami vs Scotch Cap Lighthouse,1946

Slide30: 

The Scotch Cap Lighthouse 1946 (after)

Bam, Iran, December 2003: 

Bam, Iran, December 2003 ngdir_irSistan.jpg

Turkey, 1999: 

Turkey, 1999

Turkey, 1999: 

Turkey, 1999

Slide34: 

The Great Lisbon Quake (“terremoto”) of 1755!

Slide35: 

Model depiction of range and possible propagation of tsunami waves for a possible earthquake off the coast of Portugal. 7 hr

Slide36: 

Papua-New Guinea Earthquake, 1998

The thousand-year tsunami can occur at any time!: 

The thousand-year tsunami can occur at any time!

Slide38: 

Painting by Canute Caliste of Carriacou (1992) Kick`em-Jenny: Threat of tsunami?

Slide39: 

GRENADA ST.VINCENT Kick ‘em Jenny submarine volcano is located 9 kilometers North of Grenada

Slide40: 

316,800 FEET = 60 MILES !!

Slide41: 

10,000 FEET = 1.9 MILES

Slide42: 

The velocity of a tsunami v = velocity g = the Earth’s gravitational acceleration (approximately 9.8 m/s2 at sea level ) d= the depth of the ocean v = (g  d)

Slide43: 

Example: How fast should a tsunami move in 180 meters of water ? {Depth, H=180 m} v =  (g  H) = (9.8  180) v =  1764 v = 42 meters per second This is about 94 miles per hour !

Slide44: 

Travel times for a hypothetical tsunami initiated by the submarine volcano, Kick ‘em-Jenny

VOLCANOES !: 

VOLCANOES !

Slide46: 

Examples of Origins of Volcanoes Divergent Plate Boundary HOT SPOT SUBDUCTING PLATE

Slide47: 

Volcanic eruption on the surface of Io, one of Jupiter’s satellites

Slide48: 

Volcanoes form at the ridge(s) and at the subduction zones

Slide49: 

The Pacific “Ring of Fire”

Origins of Volcanoes: 

Origins of Volcanoes Volcanoes originate in a few ways: As a result of subduction at a plate boundary. Example: The Caribbean volcanoes At a rift zone where spreading occurs. Examples: Iceland, Oldoinyo Over a “hot spot” Example: Hawaii

Slide51: 

St.Croix Guadeloupe Barbados Kick’em Jenny Antigua Dominica Martinique Anguilla Caribbean Island Arc (subduction zone) volcanoes Montserrat St. Lucia St. Vincent Saba

Slide52: 

Oldoinyo Volcano in the African Rift Valley

Slide53: 

“Hot spot” Volcanoes form as a plate moving over the hot spot is melted Ocean Plate

Slide54: 

Hot Spot Volcanoes formed the Hawaiian Islands

Slide55: 

USGS

Slide56: 

Kilauea -- A Hot Spot Volcano in Hawaii

Slide57: 

Pu’u O’o of Kilauea, Hawaii

Slide58: 

Viscous (basalt) lava flows through a forest.

Slide59: 

Slow moving lava at Wahaula

Slide60: 

Lava from Kilauea Volcano burns the Wahaula Visitors Center.

Slide61: 

An eruption of Mount Vesuvius (20th century)

Slide62: 

Pompeii was destroyed by Mount Vesuvius in 79 A.D.

Slide63: 

South East Asia Volcanoes The Krakatau Volcano exploded in 1883 obliterating the island and creating a tsunami that killed 36,000 people.

Slide64: 

Volcanoes forming at a subduction zone

Slide65: 

Mount Saint Helens ( a subduction zone volcano) before May 18, 1980

Slide66: 

Mount Saint Helens May 18, 1980

Slide67: 

A Pyroclastic flow from Mount Saint Helens, which continued to be active for months after its 1980 eruption.

Slide68: 

Lyn Topinka’s photo, May 19, 1982 Mount Saint Helen Volcano

Mount St. Helen’s Dome Growth: 

Mount St. Helen’s Dome Growth USGS Oct 14, 2004 USGS Oct 12, 2004

Recently active Caribbean Volcanoes (all at subduction zones): 

Recently active Caribbean Volcanoes (all at subduction zones) Areal and El Chichon of Mexico Pelée of Martinique Soufrière of St. Vincent Soufrière of Guadeloupe Dominica’s volcanoes Soufrière Hills of Montserrat Kick `em Jenny under water near Grenada

Slide71: 

Lesser Antilles Subduction Zone I M S M M

Slide72: 

The three arcs occur at the eastern leading edge of the Caribbean Plate.

Slide73: 

St.Croix Guadeloupe Barbados Kick’em Jenny Antigua Dominica Martinique Anguilla Three Arcs: Actively volcanic islands (inner) Limestone Caribees (middle) Accretionary Wedge (outer or eastern)

Slide74: 

Saba The Quill, ‘Statia Liamuiga Nevis Peak clouds The inner, volcanically active island arc in the Caribbean Sea starts at its northern end with seamounts east of the Virgin Islands and ends with Grenada.

Slide75: 

Susan Edgecombe photo, 2000 Montserrat’s Soufriere Hills Volcano

Slide76: 

Roseau 28,000 years ago, Dominica experienced the greatest volcanic eruptions of all the Caribbean Islands. Morne Trois Pitons Micotrin

Slide77: 

Boiling Lake, Dominica, really boils. It has done so for centuries. RAW

Slide78: 

An 1888 Lithograph of Dominica’s Boiling Lake

The Products of Volcanoes =========================================: 

The Products of Volcanoes ========================================= lava flows ash gaseous emissions pyroclastic flows and surges tephra mudflows (lahars)

Slide80: 

Soufrière Volcano on St. Vincent is a true stratovolcano It has erupted in 1718, 1812, 1902, 1971 and 1979.

Slide81: 

Kick `em Jenny Submarine Volcano North of Grenada

Broader Effects of Volcanoes ======================================: 

Broader Effects of Volcanoes ====================================== Formation of new lands Gases in the atmosphere Rocks and soil Geothermal energy Climate/weather change

Slide83: 

The Pitons of Saint Lucia are the remaining cores of earlier volcanoes RAW

Key words and terms=======================: 

Key words and terms ======================= epicenter to propagate liquefaction rarefaction utilities to inundate Seismology p-waves s-waves Modified Mercalli Index Richter Scale

Key words and terms =======================: 

Key words and terms ======================= ring-of-fire magma lava subduction intra-plate “hot spot” divergent boundaries

Earthquakes, Tsunamis, Volcanoesas Tectonic Plate MotionPhenomena: 

Earthquakes, Tsunamis, Volcanoes as Tectonic Plate Motion Phenomena The End