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The majestic Andes of South America did not rise smoothly and gradually, a team of geologists reported in Science.1  Instead, long periods of stasis for tens of millions of years were punctuated by rapid periods of uplift.  It sounds as if punctuated equilibria theory has been stolen from evolutionary biology and applied to geology.  They […]

Amphitheater-shaped canyons are common throughout the West – and even on Mars.  Geologists had them pretty well figured out.  Water seeps out the bottom of a wall, weakening the face of a cliff.  Gradually, material collapses and leaves a large alcove that continues to recede headward.  That idea is now questioned by a new theory […]

Just when the park rangers were getting familiar telling the public the Grand Canyon was carved about 5 million years ago, some geologists announced the shocking news that it might be less than a million (05/31/2002, 07/22/2002).  The age was plummeting as recently as November (11/30/2007).  But then last month, another revision came: it’s 17 […]

One would think that the Grand Canyon, one of earth’s most prominent geological features, studied by geologists for 140 years, would be well understood.  Wrong.  “The Colorado River’s integration off the Colorado Plateau remains a classic mystery in geology, despite its pivotal role in the cutting of Grand Canyon and the region’s landscape evolution.”  That’s […]

Remember the “Lost City” deep sea vents that were discovered by surprise in 2000 (12/13/2000)?  It appears that they are producing large quantities of hydrocarbons (methane, alkanes, ethene, acetylene, propene, propyne) without the help of living organisms (cf. 08/13/2002).  A team of scientists deduced that abiogenic reactions like the Fischer-Tropsch process and others may be […]

The rate of calcium carbonate precipitation can double if microbes are present, says an article in PhysOrg.  Scientists studying hot spring deposits in Yellowstone made this “surprising discovery about the geological record of life and the environment.”  The article adds, “Their discovery could affect how certain sequences of sedimentary rock are dated, and how scientists […]