Archive for January 2, 2009

USGS Has Another Nice Publication

The title is Preliminary Assessment of Volcanic and Hydrothermal Hazards in Yellowstone National Park and Vicinity.

I would strongly recommend reading it whether you are in the park or the vicinity.

“Vicinity” could well mean “within the continental United States”.

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6 Squadrons of P-8A Poseidon Aircraft to Be Stationed at NAS

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Governor Crist Appoints Jorge Labarga to Florida’s Supreme Court

Well, let’s hope that Florida will no longer have the distinction of having one of the nation’s worst courts, but I don’t have any evidence to tether that hope to.

After reading the story, sounds like just another liberal.

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Jacksonville’s Murder Count for 2008

2008 homicide count was 143, with the 2007 count 152 and 2006 count 137.

So, do you feel safer now?

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Yellowstone Lake

Abstract

The heat flow map of Yellowstone Lake shows a complex thermal regime with variations of more than two orders of magnitude. The major geothermal systems mapped are within the caldera boundary, in the northern part of the lake and in West Thumb.

In the northern part of the lake two areas of extremely high heat flow are identified: an area east of Stevenson Island (heat flow more than 10000 mW/m2), not previously known to have high heat flow and Mary Bay-Sedge Bay geothermal system (up to 40000 mW/m2). These are separated by an area with background heat flow of 1500 to 2000 mW/m2 which correlates with large sediment thickness. Therefore the whole area from east of Stevenson Island to the Mary Bay is interpreted as a single geothermal system variably attenuated by the conductive effects of the sediments.

Seismic data show that the western boundary of this high heat area is the complex graben which extends from the Lake Hotel in an approximately north-south direction east of Stevenson Island. We present evidence (heat flow, seismic and geologic features observed from underwater video) that the Hotel Fault, one of the graben faults, extends on the east side of the Stevenson’s Island, not on the west.

West of the graben the heat flow could be as low as 150 mW/m2. Although several topographic notches similar to the hydrothermal vents east of Stevenson Island were identified west of the graben structure, the nearby heat flow values are low, suggesting the presence of cold, not hot springs. The decrease of the gradients to the south is more gradual and is not associated with major faulting or with the caldera boundary. The other important geothermal system is West Thumb, but no extremely high heat flow values were found.

The areas east of Stevenson Island and Mary Bay – Sedge Bay are identified as potential geothermal hazards. However, in Mary Bay, at the hottest point located in the lake, the boiling point temperatures are reached at more than 5 m below the bottom of the lake, in a water depth of 40 m. If a geothermal explosion were to occur it would require a sudden drop of water level with at least 6 m.

By connecting several discontinuous features it has been argued that the maximum possible length of the Hotel Fault, the largest fault in the lake, is 25 km. However, the fault was mapped only north of Stevenson Island (for about 3 km). In the south it could be masked by deformed area in the east of Stevenson Island (up to 8 km). No link to the Eagle Bay fault to the south was observed in sparker records and thus the maximum fault length is only 12 km.

We argue that a fault 12 km long could not offset the bottom of the lake by 6 m. The overall low stress condition in the caldera (weak crust) support the presence of a high number of small events rather than large single fault events.

Mary Lake Seismic Traces 01/02

Mary Lake Seismic Traces from 12/25

The park and roads appear to be open. If I were a tourist, I’d be worried about that lake and possible calamitous flooding from a geothermal event under that lake.

That is, if I were aware of it.

I understand that it has been quite windy in Yellowstone, and I suppose the wind could be producing the noise on the tracings.

Yellowstone Lake Seismic Traces.

Yellowstone Lake Seismic Traces from 12/26.

Capital Commerce is also following this story.

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