August 2005

The September issue of Geology has an interesting article on dating the Lovejoy Basalt deposits of Northern California, which form a patchwork of basaltic outcrops that are Tertiary aged. Paleomagnetic evidence and geochemical analysis suggest that these flows are part of the Yellowstone flood basalts that erupted around 17 - 14 million years ago. The paleomagnetic evidence also demonstrates that the uppermost flow traveled a minimum of 75 km and that some others could have traveled 200 km or more. It appears likely that the Lovejoy basalt was part of the same 17-14 million year old outpouring of lava flows attributed to the Yellowstone hotspot, which comprise the voluminous Columbia River flood basalt and high plateau lavas of Washington, Oregon, and western Idaho, greatly expanding the extent of Yellowstone hotspot volcanism to the southwest. The article itself isn’t available, but you can read the abstract here.

Paleontologists from 21 countries gathered in Beijing recently to discuss decreasing bio-diversity on Earth and how humans may be responsible for the sixth mass extinction event in Earth’s history. The article is available here, but unfortunately it’s fairly ambiguous and slim on details of the meeting or the overall conclusions of all scientists involved. About 15,000 species are disappearing, more rapidly than any time in history, according to the 2004 global species survey issued by the World Conservation Union (ICUN). Figures published in nature, a leading scientific journal, indicated that about one million land organisms would disappear in half a century.

A conference on global warming being held in Greenland recently came to an end. Representatives from 22 countries attended. “There was a great desire to push ahead, to do something,” said French Environment Minister Nelly Olin, noting that “everyone was aware of the urgent problems to be resolved and the need to act.” Also in Greenland, the Ilulissat glacier has receded by nearly 10 kilometers in only a few years. Meanwhile, on the other side of the planet, the presense of sea ice in the Antarctic is on the rise. A new super computer in Europe will make it possible to model and analyze climate change and scientists in the United States have begun field testing to try and unite climate and weather models.

In 1996, a rockfall in Yosemite National Park killed a 21 year old rock climber. Based on a study by Skip Watts, a geology professor from Radford University, the climber’s parents have filed a $10 million dollar wrongful death lawsuit against the National Park Service. The lawsuit has the potential to permanetly ban climbing in Yosemite. Preparing to rappel off the cliff face, Watts was surprised by the smell of sewage wafting from leaking pipes at the old bathrooms atop Glacier Point. He theorized that the errant effluent helped trigger the 1996 rock fall. His curiosity grew as rock falls occurred in November 1998 and May 1999. Then on June 13, 1999, the slide that killed Terbush let loose in the same area. Studying a photograph, Watts traced the fractures on Glacier Point’s rock face. Arching upward, the cracks continued to the bluff top, where Watts discovered what he considers the culprit: Water overflowing from a 300,000-gallon storage tank.

Here is some more information on a previously covered topic. Drilling is set to begin in September, on a crater located in the Chesapeake Bay. They are planning to drill over 7,000 feet into the Earth’s crust! I had no idea they were planning to take cores from that far down. “We’ll be crossing bridges that nobody’s crossed,” said USGS scientist David Powars, one of the first to suspect an impact crater lay under the Chesapeake Bay. Powars and other scientists, trying to figure out why some aquifers were salty and why older fossils could be found l ying on top of younger ones, announced the existence of the crater in 1994. For decades prior, such strange evidence had been considered the results of poor sampling and poorer science, rather than the ground truth of a cosmic collision. Here is the USGS web page on the project and more information as well.