As dates in geologic history go, the formation of the slender land bridge that joins South America and North America is a red-letter one. More than once over the past 100 million years, the two great landmasses have been separated by deep ocean waters. The narrow section of Central America that now unites them–at its narrowest along the isthmus of Panama–changed not just the world map, but the circulation of oceans, the course of biologic evolution, and probably global climate. The tortured product of diverse forces, today’s version of the isthmus was probably fashioned by volcanism and movements of tectonic plates somewhere between 15 million and 3 million years ago.
|Name||Title||Fields of interest|
|Mark H. Anders||Associate Professor||Continental deformation using structural geology, seismology, and and other disciplines.|
|Nicholas Christie-Blick||Professor||Sedimentary Geology and Tectonics|
|Peter B. Kelemen||Arthur D. Storke Memorial Professor|
|Paul E. Olsen||Arthur D. Storke Memorial Professor||paleontology, stratigraphy, Evolution of continental ecosystems (climate change, mass extinctions)|
March 31, 2014
July 09, 2013
A new study in the journal Nature provides fresh insight into deep-earth processes driving apart huge sections of the earth’s crust. The process, called rifting, mostly takes place on seabeds, but can be seen in a few places on land—nowhere more visibly than in the Afar region of northern Ethiopia. (See the slideshow below.) Here, earthquakes and volcanoes have rent the surface over some 30 million years, forming part of Africa’s Great Rift Valley. What causes this, and does it resemble the processes on the seafloor, as many geologists think?
January 23, 2012
In California’s Death Valley, death is looking just a bit closer. Geologists have determined that the half-mile-wide Ubehebe Crater, formed by a prehistoric volcanic explosion, was created far more recently than previously thought—and that conditions for a sequel may exist today.
August 31, 2011
A new study suggests that Homo erectus, a precursor to modern humans, was using advanced tool-making methods in East Africa 1.8 million years ago, at least 300,000 years earlier than previously thought. The study, published this week in Nature, raises new questions about where these tall and slender early humans originated and how they developed sophisticated tool-making technology.
November 05, 2008
Proposed Method Would Speed Natural Reactions a Million Times
Scientists say that a type of rock found at or near the surface in the Mideast nation of Oman and other areas around the world could be harnessed to soak up huge quantities of globe-warming carbon dioxide.
October 28, 2006
For several decades, geologists have thought the western North American tectonic plate was riddled with a type of fault that permitted the continent to expand over the past several million years. However, a new study published in the November issues of The Journal of Geology challenges that assumption and suggests that these faults are actually the remains of massive, gravity-driven rock slides and not tectonically active features of the Earth's crust.