Geology

What is the impact of volcanic sulfate emissions on climate? Researchers have completed the most accurate and precise reconstruction to date of historic volcanic sulfate emissions in the Southern Hemisphere, derived from a large number of individual ice cores collected at various locations across Antarctica and is the first annually resolved record extending through the Common Era - the last 2,000 years of human history.

Reconstructions of the past are critical to creating accurate model simulations used to assess natural versus anthropogenic climate forcing. Such model simulations underpin environmental policy decisions including those aimed at regulating greenhouse gas and aerosol emissions to mitigate projected global warming. 


The earthquakes in central Oklahoma since 2009 are likely attributable to subsurface wastewater injection at a handful of disposal wells -
Oklahoma earthquakes constitute nearly half of all central and eastern U.S. seismicity from 2008 to 2013, many occurring in areas of high-rate water disposal.

These are legacy drilling operations, not modern natural gas fracking.


Tsunami earthquakes are rare but they happen at relatively shallow depths in the ocean. So while are small in terms of their magnitude, they create very large tsunamis, with some earthquakes that only measure 5.6 on the Richter scale generating waves that reach up to 30 feet high when they hit the shore. 

A global network of seismometers enables researchers to detect even the smallest earthquakes. However, the challenge has been to determine which small magnitude events are likely to cause large tsunamis.  New research has revealed the causes and warning signs of these rare tsunami earthquakes, which may lead to improved detection measures. 


Activists who are against natural gas in the United States have invented a variety of problems; flaming tap water, earthquakes, headaches, even that it will cause the earth to deflate.

Good thing they don't live in Norway, where energy extraction by the Nextdrill research project is going thousands of meters into the ground, in order to exploit another of nature's bounties:  tinkering with the Earth’s molten core and radioactive isotopes in the Earth’s crust. The project is drilling down to where temperatures are so high it can be used for district heating and electricity generation.

Two studies  presented today at the Goldschmidt 2014 geochemistry conference in Sacramento show that the movement rate of plates carrying the Earth's crust may not be constant over time. That could provide a new explanation for the patterns observed in the speed of evolution and has implications for the interpretation of climate models.  

The Earth's continental crust is an archive of Earth's history and it is the basis for studies on rock formation, the atmosphere and the fossil record - but it is not clear when and how regularly crust formed since the beginning of Earth history 4.5 billion years ago. 


There have been times in our geological history when CO2 levels were 10X what they are today, yet warming was only slightly higher.

Unlike what you often read in simplistic media accounts, there are a lot of variables in climate and weather and temperature. It takes a lot of things going wrong to turn Earth into Venus and we have never come close. 

At the Goldschmidt geochemistry conference in Sacramento, geochemists discussed one such period, but they say we just got lucky - a vast mountain range formed in the middle of the ancient supercontinent, Pangea. 


How were the earth and the moon formed? A giant impact between Earth's ancestor and a planet-sized body occurred

At the Goldschmidt Geochemistry Conference in Sacramento, researchers from the University of Lorraine say that occurred 40 million years after the start of solar system formation, which makes the earth around 60 million years older than previously thought. 


Since October 2013,  the rate of earthquakes in Oklahoma has been up by about 50 percent, which has geologists thinking about the chance for a damaging quake in central Oklahoma.

A joint statement by the U.S. Geological Survey and Oklahoma Geological Survey says that 183 earthquakes of magnitude 3.0 or greater occurred in Oklahoma from October 2013 through April 14, 2014. The long-term average from 1978 to 2008 showed only two magnitude 3.0 or larger earthquakes per year. The increased number of small and moderate shocks has led them to predict a higher likelihood of future, damaging earthquakes for central and north-central Oklahoma.

Can using a well move a mountain? It will if the well is big enough.

Winter rains and summer groundwater pumping in California's Central Valley make the Sierra Nevada and Coast Mountain Ranges sink and rise.

How much? A few millimeters each year. That doesn't sound like a lot but it creaes stress on the state's faults that could increase the risk of an earthquake.

Gradual depletion of the Central Valley aquifer due to groundwater pumping also raises these mountain ranges by a similar amount - about the thickness of a dime - each year, according to a new paper in Nature. That cumulative rise over the past 150 years could be up to 6 inches, according to calculations by the geophysicists. 


A new discovery in the study of how lava dome volcanoes erupt may help predict how a volcanic eruption will behave.

Volcanologists say a process called frictional melting plays a role in determining how a volcano will erupt, by dictating how fast magma can ascend to the surface, and how much resistance it faces en-route.

The process occurs in lava dome volcanoes when magma and rocks melt as they rub against each other due to intense heat. This creates a stop start movement in the magma as it makes its way towards the earth's surface. The magma sticks to the rock and stops moving until enough pressure builds up, prompting it to shift forward again, a process called stick-slip.