In the South Pacific, south of Late Island along the Tofua volcanic arc in Tonga, a new volcanic island Home Reef is being re-born. The island is thought to have emerged after a volcanic eruption in mid-August that has also spewed large amounts of floating pumice into Tongan waters and sweeping across to Fiji about 350 km to the west of where the new island has formed. In 2004, a similar eruption created an ephemeral island about 0.5 by 1.5 km in size; it was no longer visible in an ASTER image acquired in November 2005. The following simulated natural color image shows the vegetation-covered stratovolcanic island of Late in the upper right. Home Reef is found in the lower left. The two bluish plumes are hot seawater that is laden with volcanic ash and chemicals; the larger one can be traced for more than 14 km to the east. The image was acquired on October 10, 2006, and covers an area of 24.3 by 30.2 km.
http://photojournal.jpl.nasa.gov/jpeg/PIA01899.jpg
Archiv für Geologie
Pacific Ocean Gives Birth To New Volcanic Island
Whirlpool am Nordseeboden
Auch die Nordsee ist für spektakuläre Erlebnisse gut: Kieler Meeresforscher sind erstmals in einen Krater getaucht, der bei einem Gasausbruch am Meeresgrund entstanden war. Nach dem Abstieg durch einen Strudel von Methanblasen fanden sie einen dicht besiedelten Kraterboden vor.
Oldest Complex Organic Molecules Found in Ancient Fossils
Ohio State University geologists have isolated complex organic molecules from 350-million-year-old fossil sea creatures – the oldest such molecules yet found. The molecules may have functioned as pigments, but the study offers a much bigger finding: an entirely new way to track how species evolved.
http://researchnews.osu.edu/archive/foscolor.htm
Amazon River Once Flowed in Opposite Direction
The world’s largest river basin, the Amazon, once flowed from the Atlantic Ocean to the Pacific – opposite to its present direction – according to research by a geology graduate student and his advisor at the University of North Carolina at Chapel Hill. Graduate student Russell Mapes set out in 2004 to study the speed at which sediment in the Amazon travels from the Andes mountains, in the present headwaters of the river, to the Atlantic. While studying sedimentary rocks in the river basin he discovered something else – ancient mineral grains in the central part of South America that could only have originated in now-eroded mountains in the eastern part of the continent. If the Amazon had continuously flowed eastward, as it does now, Mapes would have found much younger mineral grains in the sediments from the Andes. Mapes explains that these sediments of eastern origin were washed down from a highland area that formed in the Cretaceous Period, between 65 million and 145 million years ago, when the South American and African tectonic plates separated and passed each other. That highland tilted the river’s flow westward, sending sediment as old as 2 billion years toward the center of the continent. A relatively low ridge, called the Purus Arch, which still exists, rose in the middle of the continent, running north and south, dividing the Amazon’s flow – eastward toward the Atlantic and westward toward the Andes. Toward the end of the Cretaceous, the Andes started growing, which sent the river back toward the Purus Arch. Eventually, sediment from the mountains, which contained mineral grains younger than 500 million years old, filled in the basin between the mountains and the arch, the river breeched it and started its current flow. Previous research has identified a reverse flow, but only in segments of the river. Mapes traversed about 80 percent of the Amazon basin.
Abstract: Evidence For A Continent Scale Drainage Inversion In The Amazon Basin Since The Late Cretaceous
San Jacinto Fault Is Younger Than Thought
A detailed study of sedimentary rocks exposed along a portion of southern California’s San Jacinto fault zone shows the fault to be no older than 1.1 million to 1.3 million years and that its long-term slip rate is probably faster than previously thought. Researchers at three universities conducted a study of the earthquake-active region, funded by the National Science Foundation, concluding that sedimentation related to slip in the San Jacinto fault zone began about 1 million years ago, significantly later than predicted by previous models.
Slip Rate Of Southern California Fault May Be Faster Than Previously Believed
Bering Strait appeared earlier than believed
A team of researchers from the Woods Hole Oceanographic Institution, the Scripps Institution of Oceanography, and the University of Massachusetts studied core samples from part of the continental shelf that was exposed during the last Ice Age. The scientists think that the land bridge between Alaska and Siberia was flooded 1.000 years earlier than previously thought.
http://scrippsnews.ucsd.edu/Releases/?releaseID=750