Presentation on theme: "This is Part 2 of 2 parts to the PowerPoint presentation covering soils and severe weather."— Presentation transcript:
This is Part 2 of 2 parts to the PowerPoint presentation covering soils and severe weather
Soil Taxonomy Allred’s summary Young often volcanic or post-quake or riverine Mature stable, aged, well-developed horizons Old oxidized, leached, too much heat & water
Page 249 Entisols, Inceptisols, Andisols – weak horizons, new minerals Vertisols – includes swelling clays Aridosols – dry country, under-developed Mollisols & Alfisols – strong horizons or profiles, world’s best farm soil Spodosols – acid, wet, sandy Ultisols, Oxisols – too hot/wet Histosols – too cold/wet
Key for general education What does all this mean? 1. What soils are best for agriculture? (humans eat grains and/or animals that eat grains, so we want grasslands) Goldilocks porridge – not too hot, not too wet, not too cold, not too hot 2. What soils are best for buildings?
Soils for buildings page 249-250 Particle size The largest are boulders or even bedrock The smallest are clays that shrink or swell with water availability
Subsidence – vertical deformation by pressure on clay or wet soils by gaps caused by removal mining, pumping or dissolving
Freeze-thaw, shrink-swell and Karst Karst – limestone that is dissolved by entry of slightly acid, carbonic water (H 2 0 + CO 2 ) Page 251 references Coke or Pepsi – bedrock may be dissolving at a rate of about 0.4 inches per year (page 250)
Sinkholes Can be caused by Karst action, removal of water, or underground erosion – water flowing underground
Thermokarst Frost heaving lifts soils, leaving voids Some buildings in Alaska are being kept ‘refrigerated’ so the soil never thaws and collapsed. The building rests on hard ice mixed with soil – permafrost Can also be called ‘gelisol’. Why?
“Ratchet” effect at ski resorts In cold season, water expands as it freezes into ice, then collapses, lifting rocks and then letting them fall when ice is gone during summer.
Scott Lake – Florida page 254 Weight of water caused ‘plug’ to break, allowing the lake to drain out. As lake debris flowed into an underground ‘river’, a new plug was created, allowing the lake to re-fill. The key is understanding the underground channels by which water moves. Channels may expand by erosion and chemical dissolution (such as Karst limestone)
Source: Diane Lacey, “The Ledger”.com, July 15, 2006 What if people had chosen to build houses in the lake area during a dry-weather period, or when the sinkholes were fully open and draining well?
Page 256 – Collapsible Soils Windblown dust, loess, loosely bound with clay. Can be stable, even in steep slopes.... Unless water and shaking persist.
Coastal uplift in some places, coastal subsidence in others (New Orleans, Venice, Italy) Vertical deformation at about 0.3 inches per year (page 265-266)
Organic Soils Prone to bio-degradation, water absorption --- collapse
Magmatic and Tectonic Uplift Lateral or vertical pressure page 257
Expansive Soils Shrink and/or swell due to water entry and/or exit
Hydraulic power of.... Water In freezing, water expands by 9% in converting from liquid to ice, exerting enough force to fracture hard metal and concrete. In absorbing water, swelling soils can exert a force of 10,000 pounds per square foot, enough to lift an office building. Page 260
Why is Taylorsville cobbles and clay? Regolith exposed near the surface – big blocks of fractured bedrock. Stream bed cobbles from eroded, broken regolith
The stream bed became ‘armor-plated’ - pavement Over time, the hillsides eroded away, leaving the ‘armored’ stream bed as the new top of the hill. The stream bed outlasted the hills. The new stream beds filled with even smaller material: sand, silt, clay.
Coal seam fires – page 269 Some in Utah, thousands in China Started by lightning or mining activity or wildfires Pennsylvania communities abandoned as earth turned hot and gooey, and gases choked the air
Billions of tons of good Utah coal may never be brought to market, because it either has a little too much sulfur (acid rain) or is under/overlain with other coal seams that have been mined out. So, either the floor or the ceiling is vulnerable to collapse.
In other cases, Utah coal seams are too near lakes (Electric Lake), roadways, power lines, surface streams, major fault lines or buildings.
Page 273 Consider the importance of mapping hazards and cataloging “best practices” to allow best use of land. Even today, many buildings do not take into account ground/soil hazards.
Timber Lakes Estates – 1980 to present We did not look at all at underground geology, only at general ‘carrying capacity’ of the area. The developer argued successfully for higher-density development, more units per acre. Many dangerous landslides are occurring.
Sometimes testing is very expensive, sometimes as much as $50,000 per building site. Ground-penetrating radar is cool, but for gamblers it is more likely to disappoint than to please.
U.S. Strategic Petroleum Reserve Page 270) 700,000,000 barrels of crude oil stored in rinsed-out salt domes in the Texas, Louisiana region. Would not last the USA for more than about a month
Chapter 9 Atmosphere and Severe Weather Note: The remainder of Chapter 9 will be sent in a new PowerPoint.
Solar energy is the most important motive force for humans. Solar budget: for every 100 photons coming IN: 31 are reflected out 69 are absorbed, so 69 must radiate back out at night, during winter, etc.
Where would we be without the atmosphere? World average 5°F instead of 59°F and extreme variability: 500 degree change from shade to sun, inch to inch every minute
Which of the gases below is helping create border-line hazardous air quality in Salt Lake County this week? N 2 = 79% O 2 = 21% O 3 = ozone Ch 4 = methane CO = carbon monoxide CO 2 = carbon monoxide (rising from 280 pm to about 400 ppm PM = particulate matter (PM 2.5, PM 10 ) H 2 O = water vapor (1-4 percent by volume) Oxides of Nitrogen and Sulfur (and others) Permanent gases Variable gases Ch 4
Radiation IN (mostly short wave) Reflection Absorption Convection Conduction Radiation Re-radiation OUT (mostly longer wave)
The BIG Six: Which comes first? #3. Wind (heated air moves by having been pressurized) #2. Pressure (heated molecules vibrate more, expanding and pushing outward) #1. Temperature (solar energy converts to thermal energy we can feel) #5. Cloudiness (condensation) (when humid air cools, clouds form) #4. Humidity (heated, blowing air easily evaporates water) #6. Precipitation (if cloudy air cools further, rain and snow may fall)
Step-wise process of heating the atmosphere and water: Step 1 -- Solar energy reaches atmosphere Step 2 -- Reflection (31%) and absorption (69%) Step 3 – Absorbed energy converts to sensible heat (IR and other thermal states) Step 4 -- Transfer by Convection, Conduction and Re- radiation Step 5 -- Re-radiation to outer space – about 99.99%? -A little is stored as green plant growth (hydrocarbon) -Are we also storing a little bit more as “global warming”?
6. Change in temperature means change in pressure (higher temp, more vigorous molecule movement). 7. Change in pressure creates wind. 8. Heat and wind help evaporate water: - creating humidity as water vapor - condensing humidity back into liquid (cloud) water (precipitation) 9. Wind transfers: - heat and cold (energy transfer by moving the substances that are holding the energy - - mostly in water)
Strato-cumulus Layered cumulus clouds Consistent bottom, consistent top, but still driven by heat-releasing condensation
Cumulus cloud building as rising air speeds up by re-heating itself. Notice where things went front ordinary surface heating to genuinely unstable – Mikey likes it. So far, only a simple half-hour air-mass thunderstorm.
Massive amounts of hidden heat come back out as air rises quickly
Potentially deadly storm as vast heat comes out of ‘hiding’ – high wind as air rises very quickly. Tornadoes can result. Super cells and meso-cyclones Compare to simple Utah air mass thunderstorms
A hurricane, cyclone or typhoon could have hundreds of these.
Cloud Types – Which is the most prone to violence?
Putting “dirt” (silver iodide) into the air Why?
Virga – rainfall that never hits the ground. Why?