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DJ Define at club Parlament, Gdansk, Poland
Strobist info: blue jeled strobe on his left, green jeled strobe on his right, aditional club lighting
Lahar in the Tertiary of Colorado, USA.
"Lahars" are simplistically defined as volcanic mudflows - volcanic ash mixed with water (derived from melted snow or rain). In reality, lahars are not restricted to fine-grained sediments suspended in water. Lahars are flood events that can include relatively little gravel or an abundance of gravel - sometimes very coarse-grained.
A lahar can be a debris flow, with about two-thirds sediments and one-third water. Debris flows are so sediment-concentrated that boulders are suspended and stay at the top when the flow stops - debris flows have large rocks at the surface. This type of lahar is like wet concrete in consistency - it has a high viscosity. Once moving, such flows become sheared and end up moving quickly, more quickly than water.
A lahar can be more dilute than debris flows. Hyperconcentrated flows have abundant fine-grained sediments held in suspension by turbulence. The sediment volume of hyperconcentrated flows varies - they can be clay-rich or sand-rich, with 10% solids and 90% water to a 50-50 mix. Such flows can also have large clasts, but when actively flowing, any large rocks will appear occasionally at the surface, then disappear below. Traditionally, a flow with less than 50% gravel is called a "mudflow".
The Tertiary-aged lahar seen here is south of Florissant National Monument in Colorado, a famous locality for well-preserved fossils in an ancient lake deposit ("Lake Florissant").
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Info. from the National Park Service's Florissant Fossil Beds National Monument website:
At the roadcut you can see the lahar that originated from the Guffey volcanic center to the west. This lahar impounded the river and created Lake Florissant. The lake was about a mile wide and extended 12 miles northwards. The debris carried by the flow contained rock fragments of different size, shape, and composition. The dark fragments are pieces of Thirtynine Mile andesite (a dark, fine-grained volcanic rock that originated from the Thirtynine Mile Volcanic Complex), while the lighter, pinkish fragments are pieces of 1.4 billion year old Cripple Creek Granite that was exposed to the surface during the Laramide Orogeny. Rounded fragments may have been picked up from the paleovalley through which the lahar flowed.
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Stratigraphy: lower member, Thirtynine Mile Volcanics (Thirtynine Mile Andesite), Upper Eocene, 34-36 Ma
Locality: Route 1 roadcut ~0.2 kilometers south of Evergreen Station, northwest of the town of Cripple Creek, central Colorado, USA (38° 49' 07.34" North latitude, 105° 15' 33.85" West longitude)
Neocon 2009 Modular Introduction
Color: Legion Green, Warrior White
Installation Method: Monolithic w/Inset
Survival of the Fittest
ISA Spain: Business and Culture, Sevilla Spring 3 Spring 2012
During a bullfight, the bull fights back and captures the matador near the end of its life. The matador is caught underneath the bull.
Proverbs 31:30
Charm is deceptive, and beauty is fleeting;
but a woman who fears the LORD is to be praised.
Camera: Canon EOS Kiss Digital X
Exposure: 0.04 sec (1/25)
Aperture: f/1.8
Focal Length: 50 mm
Lens: CANON EF 50mm f/1.8 II
just bought new mag!
A Long Way
Arts and Architecture in Central Europe Summer 2012
This was taken from the end of the train tracks in Auschwitz-Birkenau. Through the trip, we learned about the Jewish history of Central Europe. To think of how many people had passed this place to go to their death is unimaginable.