Friday, July 26, 2013

PENT Env Geol


What Portage/Winnipeg looked like before the Ice Age (probably)

UN : in 10 years (1994-2003)                                     

 500,000 have died  (before the 2004 tsunami)      

&   2.5 billion affected worldwide

Mostly from floods & earthquakes


“State of the planet”

By National Geographic, 2002
Not good, yet most findings are like secrets

 SIGNS OF  
    PROGRESS    SETBACKS   WORRISOME PROBLEMS 
                                                            
  green thinking 
                                 warming       Effect of petroleum on brain
  hybrid cars                            
                                  emissions         Climate change
  recycling        
                                  wetlands
Compost toilets            dams
     Acid rain                Coral reefs
     reduction  
                                    Farmed fish 
                                    Nuclear wastes

World’s oceans in shocking decline

Worse state than previously suspected
Ocean life in at high risk of extinction due to
    Over-fishing, pollution & climate change
Recommendation to be released at the UN
Includes bring CO2 emissions down to ZERO

One award, one praise given recently

Not Oscars or Emmys or Globes, etc
Just to preserve the planet! Zero publicity
The Peruvian natives got $ 200,000 for painting their mountain white!           
Would a film star have the brain to understand that? Doubt it!
Senegal President was praised for initiating the “Great Green Wall” 

 EARTHQUAKES & TSUNAMIS

1 million killed in last 200 years

Some famous Earthquakes:
Mexico City (resonance)
Chile 1960
Sumatra 2004
Cascadia 1700  
   
Richter scale 
Proposed for California originally
Not precise in measuring large quakes
      
Juan de Fuca
Strait between Vancouver Island & Washington state
Name proposed by the Russian Academy
He started at Acapulco and surveyed west coast northwards
Was hit by pirates twice 
   
San Andreas Fault: named after the patron Saint of Constantinople 
1,280 km long
Movement along it
30 – 50 mm / year (northern part)
25 mm / year (southern part)

Canada
1,000 recorded every year, most are small

“no house ever collapsed during a quake”

Strange effects
“Earthquake weather”: torrential rain, not predicted, from extra dust
“Earthquake Hairs”: crystals of gases?
“Earthquake Lights”: like fireworks, lightning from ionized 
gases or dust

Resonance effects: Mexico City, only tall buildings failed
Small buildings shake with high frequency like hard rock
Tall buildings shake with low frequency like soil with clay
Therefore, clay soil magnifies shaking under tall buildings

Mexico City, 1985
8.1 & aftersock of 7.6 :  10,000 + died
People felt dizzy & sea-sick (vibrations)
Worst damage: buildings with 5 – 15 floors
Los topos (moles), esp. La Pulca (the flea) who saved 27 people
   19 “los milagros” (miracle babies) rescued up to 9 days after quake
   scandal-torn Government collapsed
Ancient Mexicans built chinampas (floating   gardens) from lake mud
Later, people drained the lake (wetlands) & built on it. 
Worst possible soil for building. Seismic waves amplified even
 from 300 km away
No actual earthquakes near Mexico City!
Subduction fault at Acapulco

Earthquake storms
Alexandria 365 AD, The “Universal Event” with 11 major quakes
 in 12 years in Eastern Mediterranean, like a “seismic crisis”
Each event triggered another in the same general area

In North America
An earthquake along the Cascadia Fault can trigger one 
along the San Andreas Fault
and vice versa
Both faults along the same line

     More recently, Parkfield, San Andreas Fault:  was
 “the E. capital of America” = a quake every 22 years. 
But in 1988 nothing happened, next event was in 1992 
in nearby Landers plus another at Big Bear. Each event 
shifts stresses to the surroundings where the next earthquake takes place  

ANATOLIAN FAULT : 1939, 1942, 1967. It was predicted 
that next would be around Izmit & it came in 1999 with 30,000 victims. 
Next maybe Istambul Fault was traced under Sea of Marmara 
where a valley was discovered    

CHILE  1960  1,000 km-long zone of rupture, 160 km offshore. 
Land thrust upwards, elsewhere downwards, entire villages 
disappeared, landslides, 6 volcanoes woke up plus 3 new ones,
 tsunami killed 56 in Hawaii, 32 in Philippines & 138 in Japan                                     
 People went crazy from the shaking, that resorted to murder & 
cannibalism, beating up a 6 year old boy to death and throwing 
his heart to the sea to calm it down        Altogether 5,700 died  

What happened in Chile can happen in Cascadia
Subduction zones: where the ocean plate goes under the continent
Most violent earthquakes
Because subduction takes place under the sea, tsunamis are generated too
    
Cascadia 1700 AD
Native legends on Vancouver Island
New evidence in 1990’s from sand layers in the soil & dead forest along coast
Carbon dated to 1700 AD
Detailed records in Japan point to a tsunami not locally generated

legend
See Pachena Bay Nation

Tsunamis hit the coast around mid-night, Jan. 27
Also hit Japan, 8,000 km away, 10 hours later
13 large earthquakes took place in the last 6,000 years along Cascadia
Years between quakes 300, 390, 500, 1,000, 600… average 400 years

Video: Shock Wave  : Cascadia earthquakes
Port Alberni tsunami of 1964: people didn’t know what it was
Laser survey on top of mountains: movement takes place
Movement to the E, after 14 months slips westwards
Ghost forest along the shore /sand layers
Underwater slides along continental shelf
Evidence of 39 subduction earthquakes
Cascadia Fault association with San Andreas Fault
Steps to be taken:
   1. science of earthquake prediction
   2. earthquake-safe construction
   3. be prepared, education of the public
How a tsunami will hit depends on the depth of water & shape of land
Computer models of coastal towns to see possible effects
Need to keep warnings as part of culture
It is only a disaster if we don’t prepare
Crescent City, Calif.: tsunami hot spot

TSUNAMIS  20th Century : 141 damaging with 70,000 deaths
 + 900 small with no damage              
--Newfoundland 1929 : 28 died       
--Largest on record : Kamchatka 1737 : 70 m high                       
Other causes : landslides, meteor falls, underwater slides 
(Papua New Guinea 1998: 15 m high, killed 2,500 – a big surprise) 

Tsunamis in History
Santorini (Atlantis?) volcanic eruption
~ 1,650 B.C.
Tsunamis hit Crete and destroyed the Minoan civilization,
 the oldest in Europe
They had pipes to bring fresh water to houses and another 
system of pipes to take waste water away
Pottery, elaborate paintings on walls, gold
World mariners, must have explored all the oceans
Minoans left with unknown destination
Since most lived in Crete, they were also known as Crees
First settlers in the Gulf of Mexico came from somewhere around 1,200 BC
Maybe those were the Cretans or Crees
The Egyptians called them “Sea Peoples”. They were importing 
/ exporting for them

Alexandria 365 AD (where Cleopatra ruled)
Major earthquake with tsunami
50,000 died
Tsunami littered the city with boats
The classic warning sign was observed : the sea moved out
 before the tsunamis hit
Detailed description exists

Pacific Tsunami Warning Centre
Established in Hawaii in 1947, after the devastating tsunami
 of 1946 (157 died)
Only serves Pacific Ocean countries
Proposal to start an Indian Ocean Tsunami Warning system r
ebuffed by India: “there is no need for that”
More damage to Hilo in 1960 from Chile’s 9.5 earthquake

1960 - 2004
No major tsunamis for 44 years
People don’t know what a tsunami is
Some still call it a tidal wave, so, it can’t be lethal
Big surprise comes to all in 2004 and this time it is not 
in the Pacific ocean

Scientists worry
Fake posters made to warn people, especially in California
Also, fake tsunamis in movies were made
Not very effective method
Still the general public is unaware

Dec.26, 2004 : Sumatra
9.0 /9.3 on the Richter scale
2 earthquakes + 6 tsunamis
                                   1st: 1 m
                                   2nd : 10 m
                                   3rd: 10 m
                                4 – 6 : small

~ 300,000 killed and thousands injured
Everyone caught by surprise
Locals and thousands of tourists from Europe and N. America
Only 2 kids knew about tsunamis in that area - both tourists
Many short videos exist from the tourists who happened to 
be filming at the time

A 9-year old convinced her hotel people to move to the top 
floors after she convinced her parents
A 10-year boy from the UK screamed “a tsunami” as his dad 
happened to be videotaping the sea at the time – unaware that 
the tsunamis were approaching
Even when the tsunamis were hitting, people were still unaware 
what those waves were

The Americans blamed terrorists who created waves!
Some of the old folks knew vaguely
The “primitive” tribes were completely aware of them & moved to high ground
The animals (elephants) broke chains to move to high ground
It is only the “moderns” who were not educated

Some of the scuba divers noticed strong currents in the sea
No fish were to be found, so the fish knew all about it and fled
to escape the currents

Japan: March 11, 2011
Fukushima nuclear plant damage
Dramatic tsunami videos
Up to 14,000 died
Many youtube videos this time. Even the Japanese,
the most prepared in the world for quakes / tsunamis,
they got caught

SUMATRA 2004  Dec.26  9.0 to 9.3 second strongest
in recorded history   displacement of 10 m seen by camera = 100 years
of accumulated stress released
Quake affected earth’s shape = more round, decreased length of day
 by 2.68 micro-seconds & waves reached everywhere  on the planet
 (Nova Scotia a day later) satellite saw them. Survivors found after 3
weeks drifting on rafts & logs eating coconuts

1 picture of a tsunami in Hilo, Hawaii : 1946 (10 m ), 1960 (10.5 m )
Nothing since Okushiri, 1993 : 15 m high, then a mystery second
arrived from the opposite side (wrap-around wave)  200 died  
Lab tests : force of 4 tons / m2

Sumatra, 2004 1,200 km of fault ruptured   Banda Ache 30 m high
  Thailand got the –ve part (sea retreats) & Sri Lanka got the +ve part
(big flood)   Then a 3rd mystery wave reflected off the Maldives & hit Thailand

Lituya Bay, Alaska, 1958 : People witnessed a monstrous wave.
Took 42 years to solve mystery.    
Culprit was a landslide with an air pocket shooting the water way up
 --Hawaii, west slope of big island: unstable slope amenable to a huge
landslide that can devastate Honolulu 30 min away



Investigations for pre-historic tsunamis
Many major ones have been found
Meteor hit South Pacific ~ 1,500 AD. The Maoris in New Zealand 
moved uphill
Norway, 8,000 years ago: largest known submarine slide
Canary Islands landslide formed a tsunami that hit east coast of the 
USA (another is imminent)

MAN-MADE EARTHQUAKES 
--deep injection wells   --reservoir lakes for dams   --mine cave-ins

QUARKS : fundamental particles from collapsed stars that
 travel at supersonic speeds                                                          
Size of a human cell but weigh a ton !   
 cause quakes with “unassociated events” ie. Without a known fault                                  
Go in straight line across earth, but 40 X faster & release power 
of atom bomb going through (this is the quake)                                                           
Two such events, Oct. 1993 & Nov. 1993 in Australia / Antarctica. 
Have to be recorded by a min. of 7 stations to be legitimate 
         
 VOLCANIC HAZARD
80,000 died in 20th Century
   
Active recently
       Chile : ash problems in Argentina, Australia: plane cancellations
       Iceland: 2 eruptions, airplane cancellations all over Europe
       No deaths (volcanoes in remote locations)
Some bad cases                            
 --Toba, Indonesia, 75,000 y. ago crater 100 km by 35 km reduced
                human population to 10,000 from famine                                          
--Tambora, Indonesia, 1815 (1816= Year without summer) 
                 Famine in Canada & Switzerland                  
 --Krakatau, Indonesia, 1883 deafening noise
-- Laki, Iceland, 1783 10,000 died also famine in Egypt & India 
             (I million died)                                     
-- Vesuvius, Italy, 79 AD buried Pompei with 2,000 gypsum 
                casts of victims found                                  
 -- Stromboli, Italy : erupting for 2,400 years
        “Lighthouse of the Mediterranean”                              
  -- Kilauea, Hawaii, erupting continuously since 1983

Cascadia Volcanic Belt

 -- Mt. St. Helen’s (Fire Mt) Big surprise in May18, 1980 

          Erupted sideways                                        
 -- Mt. Rainier (Takoma)  “Disaster waiting to happen” next?

Living in the shadow of volcanoes :  Vancouver, B.C. 

-- Mt. Baker (Sleeping Giant) last eruption 7,000 y. ago 

                       mudflows, lavas                                               
 --Mt. Garibaldi last eruption 13,000 y. ago, last activity 1856                  
 -- Mt. Meager last eruption 2,400 y. ago pumice

How to monitor a volcano 
( Treat it like a patient)
After the failures of Mt. St. Helen’s  a Volcano Assistance Program only 25 %

  of active volcanoes monitored   
                       
 --Take its pulse : set up seismometers to record movements                                        
 -- Take its temperature -types of gases emitted
     (The more sulfur gases are emitted, the closer the magma is to the surface)                            
 -- Check its bowel movement – what came out before prob. similar
      will come out in the future              
 --Reconstruct its history

MT. ST HELEN’S: May 18,1980
 The largest landslide in recorded history. Last eruption in 1857          

 First activity March 20                      Bulge grew on northern side          
A 5.1 earthquake before eruption sideways, later upwards too. 
Eruption for 9 hours.              
Intense lightning & strong wind to feed the updraft                          
 57 died  700 X atom bomb

VOLCANOES & MASS EXTINCTIONS 
large volcanic eruptions linked to crop failures, starvation & famine

 Prob. responsible  for at least 2 mass extinctions :                                                     

  –65 m.y. ago extinction of dinosaurs (just the meteorite impact could
         not have produced enough dust) &                               
-- 93 m.y. ago when undersea volcanism caused extinction of 
         foraminifera (they form deposits of oil & gas)

A super-volcano: Yellowstone

caldera 75 km X 45 km                    highly active since 1970,
surface rising & falling                                   

A Hot Spot: the only one under land Its path traced for 700 km in last 17 m.y.
     with 100 major eruptions  3,000 earthquakes / year
This volcano will challenge civilization: warning


Rocks hot & plastic: impossible to have big quake                             
Last 3 eruptions: 2.1 m.y., 1.3 m.y., 640,000 y.
(“volcanic winter” lasted 10 years)                            
 Underneath: banana-shaped magma chamber several km deep,
  then a 600 km pipe to NW link to mantle

Volume of ejected material

St. Helen’s, 1980: 2 km3
       Pinatubo, 1991: 10 km 3
       Tambora, 1815: 160 km 3
       Toba, 75,000 years ago: 2,800 km 3
        3 Yellowstone eruptions : 6,000 km 3

MUD VOLCANO: INDONESIA  
drilling for oil/gas started May 2006 Used no metal casing (required)
 Abandoned when Mud started flowing out. Up to 100,000 m3/day 
Stinks & is hot.  13 died & 50,000 displaced 
People complained when mud up to chest high. Covered 20 km 2
Experts: result of drilling 


New volcanic island

       Born in 2009
       Explosion created a new island
       There are 36 undersea volcanoes in the area
       Was captured on pictures / video
       Kingdom of Tonga -only kingdom in Pacific

Plane ride with a mystery – 1982

       Plane from Jakarta, Indonesia to Perth, Australia
1982 flight : Jakarta to Perth      St. Elmo’s fire around plane   
 Stinky smoke in cabin           Engines shut off  Re-started just before crash                             
Fine glass causes abrasion Jet’s combustion at 2,000’C  

Ash melts at 1,200’C & clogs up engine 
Engine cools down & molten ash breaks off     
Ash invisible to radar


KRAKATAU, 1883:  The day the Earth exploded, 
The loudest bang in history

People got deaf, too much gas too fast – seawater “superheated”: 
means heated extremely fast
       People take a boat trip to Krakatau
       Pumice floated from volcano
       The animals are uneasy, hens don’t lay eggs. Eruptions become regular
       continuous tremors, then a monster noise, ear-piercing explosion, 
       every sec 1 million tons of ash down in avalanches,
        water goes out , then tsunami
       Aug. 27: ash 30 miles up, magma chamber bigger than the volcano
       Eruption filled up the air with electricity, St. Elmo’s fire, lightning
       Explosions continued all night, another big blast 
– deafening- in the morning
       At 10.02 am 13,000 atom bombs – heard in Africa 
      & Alice Springs, center of Australia
       Boat hits tsunami head on & survived,
       final blow: a nuee ardente (pyroclastic flow) over the channel onto land
       165 villages destroyed
       bodies washed over in Africa a year later
       today, population in the area is 10 X bigger
       and the volcano has grown up again…

Santorini eruption

End of Minoan civilization
Evidence of tsunami hitting Crete
Supported by evidence from bogs in Ireland and ice in Greenland


Toba eruption, 75,000 years ago

The MEGAVOLCANO
Evidence from ice in Greenland
Rocks around Lake Toba, Indonesia
Ash from the bottom of the Indian ocean

RIVERS & FLOODING

Worst flood in history

Sept., Oct. 1887, China: on Yellow river
 900,000 – 6 million died
 300 villages destroyed

The Big Flood? In legends

In China, ~ 2,000 BC
In Greece, ~ 1,500 BC & two earlier ones
Mesopotamia: ~ 2,000 BC
India: 6th cent. BC
West & Central Asia: abnormally heavy rain fell ~ 5,000 BC
Floods also when Lake Agassiz (Manitoba, ~ 6,000 BC) emptied into the sea

Annually

Summer floods in China are always deadly
Average 100 killed in the USA, esp. in the Midwest (Mississippi)
In Canada, mostly the Red River & Saint John river get flooded frequently 
– no victims

The Floodplain

Natural part of a river with deposits of alluvium (nutrient-rich)
Annual spring floods of the Nile was a blessing, it enriched the soil
By definition, it can be flooded – deadly in Rapid City, S. Dakota, 1975 
when more than 250 people died. No houses or businesses allowed there
 (can’t say the same for Brandon)

The Red River

About 900 km long, flows from Minnesota
Stretches north – south : problem, because it
    flows across different climate zones
Most frequently flooded river in Canada

worst flood (amount of water) in 1826  
  -1950 Flood: worst flooding disaster in Canadian History
 (100,000 evacuated) Floodway construction started soon afterwards
1997 Flood (Flood of the Century): if Floodway wasn’t there, 
80% of Winnipeg would be underwater
2009 / 2011 Floods : pictures
River is flooding every year to a certain extent

The Winnipeg Floodway or the Red River floodway

47 km long canal dug in gumbo (liquid mud as sticky as glue- used
 to be at bottom of Lake Agassiz)
Takes the water around Winnipeg rather than through the city
Involved more digging than both the Suez Canal & Panama Canal

One of 13 engineering marvels in the world today (equivalent to
 the 7 Wonders of the Ancient World)

How does it operate?

    The two control gates of the floodway are underneath a bridge 
where the river and floodway meet. They can be raised to elevate 
water enough to push it into the Floodway
The reason the water level has to be raised is because there is a large
 underwater mound at the opening of the canal to stop ice from going
 into the floodway. 
Only a normal amount of water continues to flow through the city

The Floodway includes the Portage Diversion
It is a 29 km long canal that “steals” the water from an over-flowing 
Assiniboine to this canal
Diverts water from the Assiniboine river to Lake Manitoba  preventing 
flooding in Winnipeg
Lake Manitoba water flows down to Lake St. Martin and through 
the Dauphin river into Lake Winnipeg (new canal opened Nov. 1st, 2011 
to take water from Lake St. Martin to Lake Winnipeg directly, rather than
 through the Dauphin river)

Other fortifications

Include dikes
The Brunkild dike is 24 km long

Rural houses south of Winnipeg

Flooded many times
New house were built on top of elevated land, they look like castles 
built on hills. Some have ditches around the hill
All we are missing are the knights riding on horses!

Assiniboine river

1,070 km long
2 tributaries: Qu’ Appelle (340 km ) from artificial Lake Diefenbaker, 
controlled by dams
   & Souris (780 km) from Moose mountain
Total length ~ 2,200 km (1/3 of Nile river)
    Therefore, this is a very long river system
The Brandon 2011 Flood was a record high flood estimated to be a 
1 in 300-year flood

Brandon, 2011

But, “1 in 300 year flood”! Is basically a joke

This is the “Recurrence Interval”, only good for insurance & security purposes
No one is studying the capacity of the watershed or “drainage basin”, 
total area of area drained by river plus little streams that flow into it, 
to see how much rainwater it can hold 
Those numbers would mean something

Saguenay Floods of 1996

Saturated ground plus 4 days of continuous rain
Water bypassed dam. River Ha! Ha! widened extensively and water 
went through town destroying many houses into Lake Ha!Ha!
Then waters hit La Baie at the end of the lake with the force of a bomb!
total death toll was up to 9

Function of Soils

Soils produce plants to feed humans and animals and are critical for our 
hydrologic cycles and water quality. Soils hold rainwater, decrease
 flooding and store water for use by plants. Sunlight is converted to 
heat at the soil surface, so soil serves as the earth’s filters and remove
 many of pollutants.
Soils are productive due to the organic matter they contain. It was created
 and stored for several millennia by the tall grass prairies

Why so much flooding?

Land has been re-engineered by humans
It is highly profitable, but vulnerable to flooding

Changes brought by humans

Fields are drained by underground pipes to lower the water table
Streams and creeks are straightened
Most of the Wetlands are gone (they purify the water, they act like 
a sponge to rainwater by absorbing it)
Floodplains are filled and developed
The water-absorbing properties of the ground are gone

Therefore, floods

Are not acts of God
They are acts of City Council & Governments
The extra water becomes a runoff and creates floods
Problem gets worse if amounts of rainfall increase
In Southern Manitoba there have been increases of between 100 
and 300 % in the amount of rainfall in 2011 leading to 20% of land
 not seeded- farmers get insurance, but no crop!

In the USA

The Great Floods of the Midwest of 1993
Were repeated in 2008, when 24 died

In Manitoba

Rivers are controlled
Water is needed to create electricity, therefore, control structures 
and reservoir lakes delay spilling the water down the river
At the moment (2012) lake Manitoba has very high level. However, 
water cannot be disposed of down the river fast enough to relieve the 
people that are flooded (due to those control structures)

Many other reasons for flooding

Flash floods (from heavy rain)
Downstream floods (Red River)
Ice jam
Snowmelt runoff
Rain on snow
Landslide dams (in the mountains)

FOREST  FIRES

in 2011 / 2012

Biggest ever wildfires in Arizona
Also, big ones in neighboring Nevada, New Mexico, California, Colorado
The Nevada Nuclear Test Lab was closed and surrounded by flames
There are ~ 30,000 drums of nuclear waste  containing plutonium sitting
 on the surface (they were thought to be underground at Yucca!)
If vaporized, they would contaminate the air

Fire triangle

3 necessary conditions in order to have a fire:
Oxygen
Heat
Fuel : forest litter ( needles, dead branches:
                                  do not decompose easy)
    

    Lightning with dry heat can trigger the fire
   Heated air rises creating a vacuum. Therefore, air rushes in to replace it, 
fueling strong winds

Forest

Who protects it?
Usually, governments protect the interests of oil/gas/hydro
Protected only if a National Reserve or Park
Infra-red scanners detect fires
High altitude spotter airplane guides the fire fighting
Fires :usually 50% attributed to human activities &  50 % to lightning

Effects of fire

Burning forest litter releases nutrients for seeds to germinate
Greek Fires 2009: new generation of olive trees, after the fire, 
had 2 or 3 times the previous yield, prob. because the fires regenerated the soils
2003 Kelowna Forest Fires: the disaster triggered a new policy: Start 
“prescribed fires” to get rid of extra fuel in the forest

Fires in Greece, 2009

Manitoba 1989 Fires (video)

24,000 evacuated from 32 communities
Nobody died
Needed almost one volunteer for every evacuee
Started in May, continued in July, ended in August
This experience has created a new preparedness effort by many communities

St. Elmo’s fire

Electro-luminescent discharge caused by ionization of the air
Bright bluish-white glow, like fire, coming out of tall, sharply pointed structures, 
such as masts, spires & chimneys
Can also appear between tips of cattle horns during a thunderstorm
Named after Erasmus, the patron saint of sailors

Retarding chemicals

Borate
Bentonite clay
Ammonium compounds

Forest

A Carbon Sink ( collection of carbon)
If it burns, it releases emissions of CO2

LANDSLIDES

Hurricanes/heavy rain cause many landslides

Since the 1990’s they are very common

These events carry too much water – like the ocean gets dumped onto the land!

Hurricane

It means “strong wind”
Now, it seems the extra water makes more damage than the wind
Other names for hurricane are “typhoon” (the monster in Greek mythology) 
& “cyclone” (which means spiral)

Hurricane Arlene: 1st of 2011

Was just bare minimum speed for a hurricane
It killed 19 people in Mexico, some were buried by mudslides, not found
 despite digging for them
Damaged 40,000 homes, 300,000 homeless
The reason for the disaster: it had too much rain – the sea was very warm & 
evaporated readily

Hurricane Sandy, 2012

Had lowest air speed for a hurricane
However, it got huge (~1,000 km across) just before it hit land (that means it
 had too much water)
Nobody could predict the damages inflicted
Catastrophic damage from storm surge (~ 4 m high) & flooding. About 60 died
Repairs would take years to fix
It was a warning to USA drivers to slow down their driving habits

Slopes

Material on slopes is unstable by definition
Need to have trees whose deep roots keep soil in place
Cutting trees for building, road making, etc makes the soil vulnerable to slides 
Rainfall increases the risk
Loggers cut trees high up on slopes (so that travelers won’t see the scars). 
This is where landslides start

World

Worst disaster: China, 1920, 180,000 died
Next worst: Switzerland in 1618 killed 1,500
Switzerland, 1806: 4 villages wiped out with 500 dead

Canada

600 deaths in last 150 years

Worst disaster: Frank, Alberta 1903, 77 died, has museum on top of debris today
Rumbling Mountain (Turtle Mt.) collapsed probably due to coal mining activities
 under the mountain

Quebec

Approx. ½ of deaths from landslides take place in southern Quebec
Areas where the “quick clays” are found in the soil (also called Leda clays)
Soils used to have salt in them, but it was subsequently dissolved away
Any vibration can turn the soil into a flowing liquid mud, like quicksand, 
esp. if this soil is exposed to the surface by erosion, deforestation, building, 
development, etc


Landslides move faster than you think..

Landslides of all sorts:
Debris, rock, mud, snow, etc
They move under gravity (force G)
Also, there is an acceleration factor
The more they fall, they faster they go
Something people forget:
           The material pushes the air in front of it
This “air blast” can kill or destroy a house, even before the mud or debris touches it

Hope slide,1965: killed 4

Coast road to Whistler, BC

solution

Geotechnical study

Prior to construction, engineers study the ground by drilling holes and 
sampling the soil / rock
Perform stress tests on core samples to measure their strength
Necessary for new public buildings
50 % of landslides are caused by humans. In the rest, humans played 
some role, not obvious at first

Causes of landslides

Undercutting
Rainfall
Vibration
Loading
People modify landscape, unaware of exposure to risks – contractors are not engineers! 

Subsidence

Sinking of the ground
Common in limestone & gypsum areas, where caves form underground
 by water that dissolves the rock slowly
Common in the Interlake, Manitoba. Used by snakes to hibernate, socialize, etc
Interlake: most reptiles in the world!?

Florida sinkhole, 2013: I victim

Guatemala city

Under the ocean

Called cenotes in Yucatan

Sacred cenote, Chichen Itza

2011

Landslides in Brazil after heavy rains
   > 1,000 people died & houses destroyed 
   All houses built illegally in the forest
           ( we learned that afterwards)

AVALANCHES

“WHITE DEATH”

60,000 soldiers crushed by sliding snow
In one day –Dec.13,1916- 10,000 perished. That was the worst disaster
Huascara, Peru, Jan. 1962: 4,000 died within 7 minutes of an ice avalanche + debris
“Winter of Terror”: 1950-51, Switzerland. Too much snow came too fast,
“sugar snow”:

    280 died in 1,300 avalanches

Yearly, ~ 150 die worldwide

Unknown disaster (in N. America) until 1860, when Gold Rush in the 
Sierra Nevada
In the 10th Century, St. Bernard, a monk in a monastery 5 km up, helped
 travelers in distress. Today, sturdy rescue dogs, but they don’t go out by t
hemselves and don’t carry barrels of brandy!

Trapped in snow

on can’t move, can’t expand chest to breath,  or fine crystals of snow 
fill up the lungs & freezes to death
Can’t survive for more than 2 hours buried
Snow contains a surprising amount of air between its crystals
One can hear noise from above, but shouting from below cannot penetrate upwards

If buried 

Can die from asphyxiation : poisoned by CO2 gas
rather than by lack of oxygen : suffocation

In Canada

Worst snow disaster at Roger’s Pass in 1910
Along the rail line. Rescuers also became trapped
There is a video made about this story on Discovery Channel
62 died in the Selkirk Mountains

Accidents every year

90 % of avalanche disasters triggered by the victims (some of them
 are “experts”)
Rescue teams have also been hit
Ski trips in the “back country”, some organized by schools (!), is where 
most of the accidents happen
Now also skidoo-triggered avalanches by people trying to ride high up 
on a snowy mountain (!)

COASTAL HAZARDS

Concerns

Rise in sea level
Freak (rogue, killer) waves in the ocean
Sinking islands

Worlds oceans in shocking decline (pollution, acids from CO2 emissions,
 “mermaid’s tears”)

Rise in sea level

End of Ice Age : sea level rose ~ 125 m
No change until 1993
3 mm / year since 1993
Predictions vary widely
Coastal erosion accelerating
Australia gave warning to 100,000 households to move (or else, no insurance)
Rest of the world taking it a day at a time

Daniel’s Harbor, Newfoundland: 2010 - video

Freak waves

Rumored for a long time
Now spotted by satellite
Project MaxWave: in last 20 years, 200 cargo ships lost at sea. 
During a 3-week period, detected 10 giant waves, 25 m + high
3 cruise ships hit by waves in the Mediterranean that smashed most
 of the windows
Mechanism: Adjacent waves could combine their amplitudes to double up their heights

Sinking islands

Most coral atolls are barely above sea level
Strong storms push salty water onto their plantations and killing the plants
Sea walls cannot stop the big waves
A few islands already abandoned, in others people planning to move
Maldives government conducted a cabinet meeting underwater to get world’s attention 

Examples

Kiribati, Marshall Islands (includes Bikini island), Nauru
 (voted as world’s happiest country), Vanuatu, Tonga, Cook Islands, Fiji, etc

Oceans declining fast -UN

Pollution (especially plastics)
Acidification
extinction 
Toxic algal blooms
Dead zones (no oxygen)
Release of methane gas trapped on ocean floor

IMPACTS

of Meteors, Asteroids  (from the Asteroid Belt) or                              
Comets  (from the Kuiper Belt, Oort Cloud)

Meteors are rocks, also known as “Falling stars”

Comets are ice with dust

“Near Earth Asteroids”

Have an orbit that cuts across Earth’s orbit
They are of variable size, but we are only interested those that are more than say, 50 m wide
Gypsumville’s meteor was 4 km big & caused a disaster
The asteroid that killed the dinosaurs was 10 km big

“1998 QE2”

2.7 km large with its own moon
Nearest was 5.8 km away, or 15 times distance to the moon
200 times further than February’s “near-miss”, but 50,000 times bigger
Must be ~ 600 of them & can cause global environmental devastation
The near-miss is also an opportunity to study it

NEA’s

Renewed interest to explore & find these potential killers
Then, you have to devise method to stop them
There are ~ 9,000 + NEA’s so far. Add 800 new of them every year

Eros

Latest: Real danger

In 2182
Asteroid 1999 RQ36, 560 m wide
Has a 1 in 1000 chance of collision
A probe is planned, Osiris-Rex in the years 2016 -2023 to collect samples

Close calls in the future

2005 YU55 in Nov. 2028
Apophis in April 2029 & again in 2036, by-passed Earth on Dec. 1012

What % of sky surveyed?

Probably 30 %
Depends who you ask
NASA was commissioned to search, but its budget has been cut
However, asteroids remains a priority for many governments

World’s religions influenced by meteorites: Christianity & Islam

Constantine saw a cross in the sky the day before a crucial battle.
He won and became Roman Emperor
He attributed his success to the cross
Last year, it was determined that it was a fireball that fell in the area
 (central Italy)
Probably, the meteor split in two giving the impression of a cross

Constantine, became a saint

Years later, Constantine established a new capital (Constantinople)
and adopted Christianity as the official religion of the Empire
(his mother is St. Helen). That is why Christianity has survived
Empire lasted for 1,100 years
Empire eventually weakened by attacks from numerous groups,
mostly Turks, Arabs, Bulgarians and the Crusaders 

Fireball in the sky: painting

Sirente

Crater is the result of impact
Dated to the 4th century
Metal fragments found in the area
Probable location of battle of Constantine

His mother Helen

Became a volcano (!) in North America
Brought  by immigrants to North America from Constantinople after
 the Fall of the Empire in 1453 AD
They also named the “San Andreas Fault” after the patron saint of
 Constantinople and the Golden Gate Bridge (which is not golden at all)
after the “Golden Horn” the bay-port of Constantinople

Mohammed (Arab  word for Moses)

Apparently saw a meteor fall down and recognized this as a message from God
Around 620 AD
All Moslems have to gather in Mecca to kiss the stone (black rock)
hidden in a black tent
They are not allowed to reveal what is in the tent to non-Moslems

Moslems

They are trying to be very religious, so they dress exactly as the Greek
priests and nuns were wearing at the time, with long robes, either white or black
Black would make anyone intolerably hot in the summer, so they stick to white

Meteorites in History

Always considered message from God & venerated throughout the world
Made daggers & knives in Greenland, Australia, India, Tibet, Egypt
(king Tutankhamen)
Temple of Artemis at Ephesos related to a meteorite fall & was kept in the shrine
One of the 7 wonders of the ancient world
Meteorite in old burial mound, New Mexico

Asia Minor

Big event: meteorite was brought to Rome in a procession in 204 BC
and built a temple
Ensisheim Fall, Germany, 1492: witnessed by many, meteorite still in a museum

Buzzard- Coulee fireball, 2008

Fireball seen over all the Prairies
60 degrees angle of descent
Fireball recorded by security cameras
Many small meteorites picked up by search teams from U of Alberta
Name of meteor from the nearest community where it landed

Feb. 15, 2013: Urals fireball - videos

Impacts is a fundamental process

The bombardment of meteors onto the planetesimals formed the
planets in the early history of the solar system
The number of meteor collisions with planets has decreased immensely
since then
Even so, 1 ton of meteors hit our atmosphere every day. The vast majority
 burns as they go though our atmosphere

“Falling stars”

A small amount of meteors create a fireball as they burn up lower in the air,
fragment into pieces and some fall to the ground
Only ~ 75 are known to have fallen in Canada in historical times
Only  ~ 20 in Manitoba
Interestingly, Manitoba has the distinction of having one guy who has
found more than 1 meteorite - Magician?

Falls v. Finds

“Falls” have been seen to fall
“Finds” have just been identified on the ground, well after they have fallen
Some meteors form a crater when they fall  with high speed
180 meteorite craters have been identified around the world (Canada has 26)
Canada has the biggest (Sudbury) crater

Other notable craters

Manicouagan at 100 km across is one of the largest in the world
Is also known as “the eye of Quebec”, can be seen from space
Both the Manicouagan meteor and the Gypsumville meteor were parts
 of the same asteroid that broke up as it entered the Earth’s atmosphere 
(they have same age) : a unique phenomenon

Meteors

Minimum speed of 11 km / sec (escape velocity from Earth)
Max. speed is 70 km / sec

Some fall very slow like a feather, so we have big rocks that show no
 depression on the ground where they lie – puzzle!

Biggest meteorite fall in history

Sikhote Alin, Siberia in 1947
Hundreds of stones with many small craters
Area known for snakes, mosquitos, tigers and bears
No explosion
Broken fragments and shrapnel, some stuck on the trees

Painting of Sikhote Alin

Tunguska, Siberia

Biggest explosion ever- still a mystery
Violent blast that leveled 2,000 km2 of forest
Big noise like gunfire & huge flame (“cut the sky in two”)
Earthquake, magnetic disturbance & radiation effects (like a nuclear blast)
Bright nights for 10 days after, worldwide

It is the speed!

The speed of a falling object may be slowed down a bit by the friction
 of the air, but it is considerable
This is what makes it a HAZARD
Meteors excavate a crater in SECONDS & cause a colossal explosion, 
thousands and millions of atomic bombs in power!!
Crater-digging depends on the material of the meteor & speed of fall

Craters

Relationship between diameter and depth
Depth = diameter / 3 approximately
Usually, crater size is 10X size of meteor
Raised rims of a crater may look like mountains from the distance
Crater may have a peak in the center or one or more rings (normally 
seen in large craters)

Energies involved

Atom bomb releases ~ 15 kilotons of TNT
Biggest bomb (USA)  ~ 15 Megatons (Mt)
Soviets biggest bomb ~ 50 Mt – not blown
Tunguska : 10 – 15 Mt
Sumatra 2004: 10,000 Mt released
Medium meteorite crater: 10 million Mt
Supernova: 10 octillion Mt

Meteorites

3 basic types:
STONIES         IRONS        STONY-IRONS
Most common    4 %                    1 %
Contain iron       heavy          look beautiful

Most of the Stonies are Chondrites: made up of rounded grains- first
 material to form in the Solar System

Carbonaceous chondrites

Are the most important
They contain organic compounds & water
Actual amino acids, capable of creating life
Some have cavities (pumice-like) example Canada’s most interesting 
is the Tagish Lake bonanza: produced tremendous amount of useful data
 & has unique composition

Tagish lake, BC

Most primitive meteorite
Contained small diamonds: literally, dust of other (pre-existing) stars
Has unusual isotopic ratios

Some meteorites

Contain small diamonds
Popigai crater in Russia has thousands of them (sorry, need a permit to visit!)
The local rocks contain graphite which turned into diamond from the
 tremendous pressure of the impact

Meteorites

Now about 30,000, but most were found recently in Antarctica – 
walk on top of the ice and every rock you find is a meteorite!

Similarly in deserts: most rusty looking rocks are meteorites!

All meteorites 

Have the same age
The Age of the Solar System
They represent original material created during the formation of the Solar System
They can be analyzed and studied for a very long time

Other information

Isotopic ratios can provide information of the pre-existing stars that 
collapsed and their remains incorporated into our sun / planets / moons
Our Solar System is relatively young compared to the age of the galaxy
Elements manufactured by nuclear reactions that start with H - He-----------
    and end with Fe

Rest of elements by supernova explosions and Red Giants-not found in 
1st generation stars
Heaviest on Earth is Uranium ( # 92)
Up to element 112 synthesized 

Re-processed stars could be sought after by other beings. Big atoms in 
big demand?
The Mo / W industrial pile mystery in the Urals, an example of an alien factory ?

Meteorite craters

2 in Manitoba
Gypsumville (St. Martin) is one of the biggest, 40 km across & 215 m.y. old
Crater excavated was ~ 10 km deep, big explosion formed strange rocks 
that outcrop on the surface today, such as
   breccia & melt rocks

Evidence of the collision with the meteor are the shatter cones & the 
shattered quartz & feldspar crystals one can see in thin section under the microscope
Other evidence is the crater that has different rocks than in the surroundings
Deposits of gypsum formed when the depressions was filled with ocean water 
that dried up leaving only gypsum within the crater

West Hawk crater

Near Ontario border & TransCanada Hwy
Only 3 km wide
Very deep lake, 100 m water, with 100 m soft sediment & 330 m broken up
 rock below that
Very deep hole created by the fall of a fast moving meteor

A BUNTEP student has found a small crater in his trap line – prob. the 
smallest in the world, about 2 m across

New science: Meteorite craters

The science is new from mid-1960’s
Before, meteorite craters were thought to be old volcanoes
Pioneer work by Eugene Shoemaker. He studied in Nevada nuclear testing. 
Realized meteor collisions were also producing as much energy as nuclear 
blasts. Besides, both events produced similar physical results

Criteria of a meteorite crater

Has to have evidence of collision & explosion
Shatter cones is the best example, but not all of the craters have shatter cones preserved
PFs and PDFs are evidence of shock waves affecting mineral grains
Melt rocks and breccias with coesite (high pressure quartz)

PFs and PDFs

Evidence of shock waves:
   Planar Fractures (PFs) and 
   Planar Deformation Features (PDFs)
   in crystals of quartz & feldspar

Also, original rocks turn into glass (meltrock) and breccias (rock made up
 of broken up rocks from the explosion)

Shock wave

When an object moves faster that it can propagate in the medium 
(solid, liquid, gas), the medium cannot “get out of the way”. Then, 
the wave is forced to go faster than normal and temperature, pressure & 
density rise extremely high (basically, explode, if you like)

Shoemaker

With the help of his wife discovered the comet that crashed onto Jupiter in 1994
First human to witness an impact
That means Earth can be hit as well
The Near Earth Program started to identify meteors/asteroids whose 
orbits may coincide with the Earth’s
Currently, over 1100 potential NEAs to collide with the Earth, but only
 a fraction of the sky surveyed 

Numerous Asteroid missions

Mission to Eros completed in 2001
Rosetta mission, Deep Impact, Stardust are on-going
A comet was blasted to retrieve dust for analysis

Volunteers needed

To survey the sky
Only 2 retired people (one in N.Dakota, the other in Australia) 
working on it besides NASA
Backyard telescope will do & schools can take up the task
Survey near horizon, no one is looking there

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