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New Insights Into Gas Hydrate Deposits
Posted on Monday, October 31, 2005 @ 4:55 pm by Dave Schumaker
Frozen methane is thought to occur in great abundance on the floor of Earth’s oceans. A team of scientists working with the Integrated Ocean Drilling Program have been gathering samples of these gas hydrates for further analysis. Scientists are interested in deposits of gas hydrates because they are thought to have played a role in global climate change in the past.
“We’re interested in gas hydrate because we believe these deposits have played an important role in ancient global climate change,” explains Michael Riedel of Natural Resources Canada’s Geological Survey of Canada, IODP Expedition 311’s co-chief scientist. “This expedition is the first to explore a transect of deep drilling research sites across the Cascadia Continental Margin and will yield new data that will help us understand the deep origin of the methane that composes the gas hydrate, how the methane is transported into the sediments where gas hydrate exists, and how methane is eventually released into the ocean, and possibly, into the atmosphere where it could impact climate.”
“What we’ve found will fundamentally change how we investigate the impact of gas hydrate deposits,” confirms IODP co-chief scientist Timothy S. Collett of the U.S. Geological Survey, Denver, Colo. “Expedition 311 has shown that the occurrence of gas hydrate is much more complex than predicted. Instead of finding gas hydrate concentrated in one layer,” he explains, “near the base of the zone where it is stable, higher concentrations of gas hydrate were found within coarse-grained sand layers throughout core samples from most of the sites drilled.”
The USGS also has a fact sheet on methane gas hydrates. One other interesting note is that it has been hypothesized that gas hydrates may have played a part in the Permian-Triassic extinction 251 million years ago.
Islamabad sits on ‘Five Major Fault Lines’
Posted on Tuesday, October 25, 2005 @ 11:40 am by Dave Schumaker
The Daily Times of Pakistan is reporting that Islamabad, the capital city of Pakistan sits on 5 major fault lines running through the city, all of which are capable of producing large earthquakes.
The GSP officials said that when the government had planned to declare Islamabad the federal capital, its seismic zoning was conducted. Geologists had warned the then government that Islamabad was prone to high intensity earthquakes because it was situated in an active earthquake zone.
The officials said that it was not advisable to construct high-rise buildings in Islamabad. They said that no building structure higher than two stories should be allowed in the federal capital, as the earth’s crust in Islamabad could not sustain the weight of high-rise buildings.
Admitedly, this article is rather week on details. However, it’s interesting in light of the major earthquake that struck the region recently and the fairly low standards of contruction present in some areas as well. See also: Asia May Be Due For More Earthquakes as well as a Wikipedia article on the Kashmir earthquake.
Course Notes for Geology Classes
Posted on Thursday, October 20, 2005 @ 3:41 pm by Dave Schumaker
A friend of mine emailed a link that I thought has the potential to be very interesting. It’s for MIT’s OpenCourseWare web page, where they have course notes (and in some cases reading lists and examples) for nearly all of their classes posted online. Especially interesting for people who read this site is the section for their Earth Science program.
You can see course notes for classes such as Structural Geology, Sedimentary Geology and even graduate level classes such as Thermodynamics for Geoscientists.
This is definitely an invaluable resource. If anyone knows of similar sites like this at other schools, feel free to post them below!
Mystery of Santa Barbara Hot Spot Solved?
Posted on Thursday, October 20, 2005 @ 3:29 pm by Dave Schumaker
The mystery hot spot near Santa Barbara in the Dick Smith Wilderness has apparently been solved by researchers from the University of California at Santa Barbara and the USGS.
The thermal anomaly is centered in a three-acre, highly disrupted slide deposit in a recently active, seventeen-acre rotational/translational landslide. The landslide is within the Eocene shales and siltstones of the Juncal Formation, a distal submarine fan deposit that contains traces of iron sulfides, organic material, and carbonate (Dibblee, 1966; Onderdonk, 2003).
Interestingly enough, I found this article on About.com who listed this website on the front page of their geology section last week! Scroll down a few posts to find out. :)
La Conchita Landslides part of Larger Slide
Posted on Thursday, October 20, 2005 @ 3:15 pm by Dave Schumaker
The large landslide that happened last January in La Conchita, California (and also happened in the same area in 1995) is actually part of a much larger prehistoric slide, called the Rincon Mountain Slide, according to researches from the University of California at Santa Barbara.
Prehistoric slides present at Rincon Mountain cover an area of about 1,300 acres with a minimum volume of about 600 million cubic yards, said Edward A. Keller, professor of earth science at UC Santa Barbara. Keller analyzed the landslide complex with Gurrola and Tim Tierney, UCSB research scientist. Geological consultant Ted Powers also contributed. The La Conchita landslides that occurred in 1995 and 2005 form only a small percent of a much larger landslide complex, according to the geologists. These recent landslides spilled over U.S. Highway 101 in the Ventura County community that is located 25 miles south of Santa Barbara.
“The slope that failed in 1995 and 2005 is a holocene paleosea cliff and is near the seaward edge of an ancient landslide that has produced prehistoric and historic slides, slumps, debris and mud flows,” said Gurrola. “The question is not if but when the next landslide will impact the community of La Conchita. A combination of factors makes future landslides inevitable. These are: active faulting and folding; rapid tectonic uplift; very weak rocks; steep topography; and, the presence of springs.”
A USGS Professional Report on the La Conchita landslide of January of 2005 here.