The Earth Story

Latourell Falls

The Columbia River Gorge has an incredible geologic history. The rocks that make up its walls are the result of a huge outpouring of lava in the Miocene, about 15-20 million years ago. The Columbia River Flood Basalts covered large portions of Washington and the Northern Oregon, possibly due to a plume of hot mantle material hitting the bottom of the continent.

The Gorge was then carved by the Columbia River over a period of a few million years. The river cut downwards, removing the igneous rocks with the aid of a few catastrophic events. A huge lake called Glacial Lake Missoula formed during the last glacial period; edges of the ice cap trapped a huge lake of melt-water behind them. When the water overtopped the ice, it melted the dam and produced an instant, catastrophic flood that eventually reached the Columbia River. That flood repeated at least several dozen, if not more than 100 times, carving the gorge even deeper.

The vertical shaft of water that is Latourell Falls is the closest waterfall to the city of Portland along the river gorge. Here it is capture almost perfectly, appearing as a vertical shaft of light. The igneous rocks that surround it show spectacular columnar jointing; a fracture pattern produced as lavas cool and shrink due to thermal contraction.

-JBB

Image credit: Kirk & Barb Nelson https://flic.kr/p/oB15DR

Read more: http://www.portlandhikersfieldguide.org/wiki/Latourell_Falls_Hike http://www.columbiariverhighway.com/columbia_river_geologic_history.htm

Original caption:

Sunset at the Portland Bill Lighthouse, Southeast UK Coast

Do have to admit I like the effect of these infrared camera nature videos. Something the eyes really aren’t used to seeing, yet familiar. Here’s Oregon. Original caption: 

Portland Stone

Portland Stone is a world famous building stone, quarried from the Isle of Portland of the Dorset coast. The sediments making up the stone were laid down during the Tithonian (150.8- 145.5 Ma) of the Jurassic. The quarries exporting the rock consist of beds of a white-grey limestone, separated by layers of chert. Portland stone formed in a subtropical marine environment in close proximity to a body of land (this is evidenced by fossilised drift wood). The stone itself is oolitic limestone. Oolites are formed from the accumulation of calcite in concentric layers around a nucleus, which can be a shell fragment, a grain of sand or any other organic fragment. Over a period of time the Oolites are "lithified"- they become stuck together by more calcite, and on the Isle of Portland this has resulted in Portland Stone. Here the limestone is sufficiently lithified to resist weathering, but is not so lithified that it can't be worked. This is what makes Portland Stone such a great building stone.

Like all good building stones, Portland Stone was known to the Romans with many Roman stone sarcophagi being carved from a single block of Portland Stone, and it was worked on and off throughout the middle ages. In the 14th Century stone was sent to Exeter to be used in the construction of the Cathedral and to London to be used in the construction of Westminster Palace. By the 17th Centuary, technology had advanced enough that it was easier to cut to the stone, and exporting Portland Stone became economical on a grand scale.

After the Great Fire of London in 1666 Portland Stone was used extensively in the rebuild. St Paul's Cathedral in London uses Portland Stone, and for a short while, by the Kings command the quarries were worked to exclusively provide stone for the building of the Cathedral. Other famous buildings in the UK to use Portland stone include the British museum and County Hall. Examples of buildings using Portland Stone across the world include the UN building in New York and the Casino Kursaal in Belgium.

As well as being a world famous building stone, the rocks quarried on Portland are also famous for their diversity of fossil finds. Finds have included extensive patch reefs made of oysters, ammonites, and even large vertebrates- Dinosaurs.

For more information head to the links below.

-LL

Links; http://www.southampton.ac.uk/~imw/Portland-Quarries.htm

http://www.southampton.ac.uk/~imw/Portland-Isle-Geological-Introduction.htm

http://www.stratigraphy.org/bak/geowhen/stages/Tithonian.html

Image; Ian West- Shows a cut section of fossiliferous Portland Stone.

Pony Tail Falls, Columbia River Gorge, Oregon. Note the broken columnar basalt chunks. 

The future of the Cascadia Fault

Portland Oregon and Sunset

Calm video trip through the Columbia River Gorge

Golden Sunrise through the door

The arch in the foreground of this spectacular sunrise shot is known as Durdle Door. It’s an arch of Jurassic-aged Portland Formation limestone on the southern coast of England. The site is visited by several hundred thousand tourists per year, making it one of the most visited sites on this coastline. Despite that, this photographer managed to capture an amazing, tranquil view of this exploding, orange sunrise.

-JBB

Image credit: Lies through a lens https://flic.kr/p/xZvgmn

Read more: http://www.worldheritagecoast.net/place.aspx?place=25 http://jurassiccoast.org/rocks-and-fossils/the-science-of-a-beautiful-landscape/1010-durdle-door-the-rock-arch

So you’ve realized you live in earthquake country…

Or really, anywhere at all. Last weekend, the magazine “The New Yorker” ran a major article highlighting the major risk of an earthquake disaster in the U.S. Pacific Northwest. Oregon, Washington, and Northern California sit atop the Cascadia subduction zone, a fault capable of producing an earthquake and tsunami comparable to the 2011 Japanese Tohoku disaster. However, large quakes in those regions are rare, happening every few hundred years, so neither building codes nor residents are prepared for them.

Yesterday I highlighted one of the most important things for homeowners in those areas; a tiny bit of seismic retrofitting can be the difference between a home being a total loss requiring demolition and virtually no structural damage (http://on.fb.me/1fRfOlh). Today I want to highlight the number 1 thing that everyone in earthquake country, or anyone at risk from any disaster should do; know where your water is.

Lots of agencies give solid lists of disaster supplies; food, radios, flashlights with batteries, first aid kits, etc., and water is usually at the top, but water deserves to be on another level. It deserves this whole post to highlight it.

Water is heavy. It takes so much energy to move water around and humans need so much of it that water is probably the most important resource to find to allow long-term space travel. People need huge amounts of water just to survive.

If you’re reading this right now, ask yourself…what would you do if your water became undrinkable for a week? Now ask yourself…what if everyone in your neighborhood was also hunting for water? What about your whole city?

The average given for normal climates is that humans need at least 1 gallon (~4 liters) of water per person per day, but in hot climates or families with young children can need over twice that amount as a minimum. Now imagine half a million or a million people needing clean water…that’s the situation where things become a true disaster. If the current water infrastructure breaks down, what would a million people do for water? How do you bring in emergency water for a million people?

The lack of water after an earthquake is a potential problem for both the developed and the developing world; both areas can suffer the same issues. Earthquakes are specifically damaging to concrete infrastructure that is commonly used in water and sewage pipes. Even if water pipes are made of metal and survive a quake, the water sources can be contaminated by sewage and whatever supplies the pressure (electricity) can be lost as well.

When Los Angeles first ran through their “Shakeout” scenario, a simulation of how emergency resources would respond both during and after an earthquake, the companies and public sector institutions involved in distributing water realized that not only would their entire infrastructure be destroyed but it would take years to rebuild the system. When the San Andreas Fault ruptures in California, it will several years for running water to be restored throughout Los Angeles.

In the long term, those water needs will be met either by imported supplies or by people evacuating the area, but what about the short term? A city like Los Angeles has 10 million+ people in the area, all of who will need a gallon of water per day. If a city loses its water supply entirely, it will take time before emergency resources can make it into that area, and water is hard to transport. It’s heavy, it takes up a lot of space, you can’t just fly planes full of water into a city to supply 10 million people, and the roads that might be used to distribute emergency water will likely be damaged too.

I’m not going to recommend any brands, but a number of websites have 55 gallon or larger water storage barrels available for sale. If you have a family and you own a home, stick one or two of those in the corner of your property. Use a search engine. If you rent and you would worry about a water barrel bursting or falling through the floor, look for some closet space, clean out some bottles, and put some water in there (instructions at link at bottom).

After hurricane Katrina, clean water rapidly became one of the most pressing needs for the remaining people trapped in New Orleans. Water supplies were gone within days and it took time to figure out where people were and to get emergency supplies into the area. That was the case in a city that had evacuation warnings issued before the event, so the majority of the population was gone. An earthquake strikes suddenly; there’s no time to evacuate the city beforehand, so imagine that same scene of people desperately needing water except in a population 100x larger.

This reminder is most important for earthquake country, but really it’s important everywhere. Floods, severe weather events, fires, lots of things can make it useful to have stored water. If I lived in Earthquake country, I’d have 2 of those 55-gallon drums in my back yard and I’d circulate the water through them every 6 months to keep it fresh. Outside of earthquake country, I still make sure I know where my water supply will come from even if I haven’t yet invested in the drums.

-JBB

Image credit: http://www.navy.mil/viewGallery.asp?id=3&page=505&r=4

Read more: http://www.ready.gov/kit http://www.ready.gov/water

This photo by Ben Canales, entitled “Lights from the hidden City” shows light pollution being reflected in winter cloud cover. This is a mountain range in Oregon. The glow in the sky is the result of reflected light from Portland, 50 miles away. -Jean