Geology News - Earth Science Current Events

The Magnitude 7.3 earthquake that struck Haicheng, China on February 4th, 1975 was successfully predicted by Chinese scientists. This prediction was accurate enough that evacuation orders were issued just hours before the ground shaking. Even though this prediction saved the lives of thousands, the details of how the prediction was accomplished were kept secret.

A new article on the Geotimes website explains that this prediction was recently confirmed as "legitimate", based upon access to recently declassified documents and interviews with scientists involved with the prediction process.

You can read the full details of the prediction in this month's issue of the Bulletin of the Seismological Society of America or read a summary titled: "Confirming a Chinese earthquake prediction" at the Geotimes website.

Labels: Earthquakes

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Empedocles is an underwater volcano located about 25 miles (40 km) off the coast of Sicily. It rises approximately 1300 feet (400 m) above the adjacent ocean floor and its summit is currently about 7 meters (23 feet) below sea level. Empedocles is not newly discovered; instead it is newly understood.


Image copyright by Geology.com and Map Resources.

Historically Empedocles was thought to be a cluster of volcanoes; however, recent studies by Cesare Corselli of the National Interuniversity Consortium For Marine Sciences suggest that it is a single cone that erupts at a central vent or at smaller vents on its flanks. Until recently, Empedocles has fooled scientists.

Although Empedocles is currently dormant it has erupted in the recent geologic past. An eruption in the third century BC elevated the volcano to above sea level, forming a small island. An island was also formed during an eruption in 1831. This eruption caused quite a political and military incident when several countries attempted to claim it as their own. Their dispute lasted a few months until subsidence lowered the volcano below sea level. Eruptions at Empedocles are not anticipated in the near future.

Labels: Volcanoes

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A news post on the Nature.com website explains why some scientists believe that southern California may be due for a major earthquake. The idea is that strain has been building up within the San Andreas Fault system for over 200 years. During that time the strain has been accumulating instead of being released through earthquake activity, "creep" or transfer into other fault systems.

The San Andreas Fault is the boundary between the North American Plate and the Pacific Plate. These plates are moving past one another at a rate of about one inch per year. However, rocks in the fault zone are stuck due to friction. Energy accumulates within the rocks and is released when the rocks rupture and the plates suddenly slip past one another.

Yuri Fialko of Scripps Institution of Oceanography has lead this study, which used radar data from European Space Agency satellites and GPS ground measurements. He estimates that there is enough accumulated energy to produce a magnitude 8.0 earthquake if it is all released in a single event.


Image by USGSRead more about his Southern California Earthquake Study at Nature.com.

Labels: Earthquakes

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Schools across the Philippines practiced earthquake safety procedures on June 19. Over one million students and teachers from 40,000 public schools participated. The Philippines has many active faults and experiences recurrent earthquakes so education and practice is a very good idea. It is an especially good idea to target schools for this preparedness as children are very vulnerable to earthquake injury.

Small earthquakes can be very dangerous to untrained children. In October 1992, Egypt was struck by a moderate-size earthquake. Over 100 children were killed by this earthquake even though the schools in which they died were not seriously damaged. These children were killed by the feet of their classmates in panic-stricken stampedes. A small amount of training and proper supervision may have been able to save many of these lives.

Read more about the Philippine Earthquake Drill at inq7.net.

Labels: Earthquakes

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Lloyd's of London has a new publication in their 360 Risk Project Series. One of the goals of this series is to stimulate debate on the growing threat of climate change and the threat to the built environment. Rolf Tolle, a Lloyd's director, says: "Although it’s almost two decades since the UN recognized that climate change was a catastrophic threat to earth, it’s clear that the insurance industry has not taken catastrophe trends seriously enough. As an industry we must work together to understand and manage these new risks, and to change our behaviour."

The publication focuses on several topics which include: greenhouse gases, sea temperatures, sea levels, land and air temperatures, rain and snow and unstable climate.


Publication Cover - Lloyd's of LondonRead more at Lloyd's Climate Change page.

Labels: Global-Warming

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The Mars Global Surveyor has transmitted photos of sand dunes from the Martian North Polar Area which is currently approaching the spring season. These dunes appear white in the image because they are covered by a seasonal layer of carbon dioxide frost. As the northern hemisphere of Mars warms the frost sublimes away exposing the dark sand below.


Image by NASA-JPL-Malin Space Science Systems

Labels: Planets

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Researchers have discovered what appears to be the oldest fossil Ornithurae - a group that includes modern birds and their closest extinct relatives. Remains of about 40 of these ancient birds - named Gansus yumenensis have been found in Early Cretaceous lake beds of the Xiagou Formation near the town of Changma, Gansu Province, China.

These fossil birds are extremely well-preserved with clear evidence of feathers, skin and webbed feet - suggesting that the birds thrived in an aquatic environment. The fossils provide information on the ancestors of today's birds and information on the transition of carnivorous dinosaurs into the birds of today.

Read more about the Fossil Birds at the Carnegie Museum of Natural History Website.

Labels: Fossils

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In 1999, Asteroid 2003 YN107 began corkscrewing around Earth, orbiting our planet once a year and tracking Earth's orbit around the Sun. It has been almost unnoticed because it is only about 20 meters across - far too small to be seen with the unaided eye. These asteroids which track Earth's orbit are known as coorbital asteroids or simply "coorbitals". The image below illustrates a typical coorbital path.

Most near-Earth asteroids streak past the Earth, but occasionally one pauses to corkscrew around the Earth. On June 10th, 2006, the Asteroid 2003 YN107 dipped within 3.4 million kilometers of Earth then shot out into a broader orbit around the Sun. It is expected to return to an Earth orbit in about 60 years.

Three other asteroids are known to be coorbitals: 2002 AA29, 2004 GU9 and 2001 GO2. More may be identified now that scientists know about them and have the ability to track and identify small asteroids. 2004 GU9 measures about 200 meters across and has been looping around Earth for about 500 years in a very stable orbit.


The typical corkscrew path of an Earth Coorbital Asteroid. NASA Image

Learn more about Coorbital Asteroids at the NASA website.

Labels: Meteor-Meteorite

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The American Geological Institute (AGI) has announced the theme for Earth Science Week 2006, which is scheduled for October 8th through 14th, 2006. “Be a Citizen Scientist!” is the theme and the goal is to help students and the public to become actively involved in earth science programs and help to spread science literacy.

AGI invites earth science educators, professionals, and interested individuals to get involved now. As in prior years, AGI will be coordinating national essay, photography, and visual arts contests related to “Citizen Science.”
Starting in August, AGI will begin distributing Earth Science Week education kits to support individuals and groups interested in holding their own Earth Science Week activities and programs. Also, the Institute is supporting public events, awareness efforts, discussion forums, and much more.


Learn more at the Earth Science Week Website.

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Ohio State University scientists have discovered a possible meteor impact crater beneath the ice of East Antarctica in the Wilkes Land area. Gravity measurements suggest that the impact forming this crater occurred about 250 million years ago - about the same time as the Permian-Triassic Extinction - the most significant extinction in Earth's history that wiped out most plant and animal species.

This crater is approximately 300 miles wide (twice as wide as the Chicxulub Crater that is often credited as killing the dinosaurs about 65 million years ago) and is hidden beneath over one mile of ice. It is possible that the force of this impact triggered the break-up of the Gondwana Supercontinent.

The crater was identified using gravity and radar data. The first image below shows GRACE-measured gravity fluctuations beneath East Antarctica. Denser regions appear more red; the location of the Wilkes Land crater is circled. The bottom is an airborne radar image of land elevation in East Antarctica . Higher elevations appear red, purple, and white; the raised rim of the crater is circled. An inset of the Chicxulub crater is included for size comparison.


Image courtesy of Ohio State University.


Image courtesy of Ohio State University.

Read more about the Antarctic Meteor Crater at the Ohio State University website.

Labels: Arctic-Antarctic, Meteor-Meteorite

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Meteorologists at Colorado State University predict a "very active" hurricane season which begins on June 1, 2006 through November 30, 2006.

"Colorado State's forecast for the 2006 hurricane season anticipates 17 named storms forming in the Atlantic basin between June 1 and Nov. 30. Nine of the 17 storms are predicted to become hurricanes, and of those nine, five are expected to develop into intense or major hurricanes (Saffir/Simpson category 3-4-5) with sustained winds of 111 mph or greater. The hurricane forecast team predicts tropical cyclone activity in 2006 will be 195 percent of the average season. By comparison, 2005 witnessed tropical cyclone activity that was about 275 percent of the average season."

See the full forecast at the Colorado State Hurricane Forecast website.

Labels: Hurricanes

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