Geology News - Earth Science Current Events

Photograph by Detective R. Gelber, Freehold Township Police Department, used with permission.

Documented cases of meteorites striking people, homes, cars or other human property are very rare. However, on Friday one of these events happened in Freehold Township, New Jersey. A meteorite crashed through the roof of a family home, bounced off a tile bathroom floor and embedded in a wall. The meteorite was about the size of a golf ball and weighed a little less than one pound. Fortunately there were no injuries.

Who owns this meteorite? Is the ownership of a meteorite determined by the concept of "finders keepers", by the laws of "land ownership", or does the government own all objects that fall from space? The answer depends upon the country in which the meteorite has fallen.

In the United States, ownership of a meteorite goes to the landowner. A person who owns land is entitled to all natural deposits which occur there - including a meteorite. If the meteorite falls on government property then it belongs to the government. So, this Freehold Meteorite belongs to the property owner (the name of the property owner has not yet been released.)

In Australia, most states have legislation that makes meteorites the property of the state museum and anyone who finds a meteorite in Australia should deliver it to the state museum who will reimburse the finder for his/her expenses.

In Canada, meteorites are property of the landowner. However, a permit must be obtained to export the meteorite and at that time a Canadian institution can have an opportunity to purchase it.

In Japan the principle of "finders keepers" applies to meteorites.

In Switzerland and Denmark all meteorite finds are state property but the finder will be paid for surrendering them.

These different laws can lead to different behaviors by the finders of meteorites. Where the state confiscates ownership, there can be a temptation to misrepresent the location of the find or sell the meteorite illegally. Where land ownership laws apply, meteorites enter the free market and can be legally traded and held by private collectors.

More details on meteorite ownership can be read in a document titled Law of Ownership and Control of Meteorites by D.G. Schmitt, McEwen, Schmitt & Co. Barristers and Solicitors.

Related items on Geology.com: Interactive Meteor Impact Map What is a Meteor?

Labels: Meteor-Meteorite

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Screenshot of chevron structures located at the southern tip of Madagascar from Google Maps. Click the image for detail.

Members of the Holocene Impact Working Group have identified numerous shoreline structures that they believe are evidence of recent marine impact events. These structures that they refer to as "chevrons" are believed to be piles of sediment that have been swept into chevron-shaped ridges by the tsunami-size waves produced from these impacts. The chevrons contain sediments, deep ocean microfossils and bits of what appear to be impact debris that are combined without regard to the normal superposition sequence.

The working group has identified numerous chevron locations - so many that it causes them to question just how often the Earth is subject to massive impact events. In addition, the size of some chevrons are enormous. Some are hundreds of feet in height and covering hundreds of acres each - large enough that they would require a tsunami over 100 feet high to construct them. These chevron structures are reported at numerous locations in Australia, New Zealand, Vietnam, India, Southern Africa, Madagascar, Hawaii, Portugal, Algeria, United Kingdom, Denmark, Brazil, Mexico, California, Washington, Oregon and other locations.


Landsat image of the Fenambosy Chevrons in Madagascar by USGS. The open side of these chevrons point directly
at a crater at the bottom of the Indian Ocean. They suggest a gigantic meteor impact occurred about 4800 years ago.
Higher resolution image.
You can read more about these chevron structures and see a world map with their locations in an article on the International Herald Tribune website. You can also visit a chevron location by clicking the google map image at the top of this article.

Related content on Geology.com: Zoom in on fifty of Earth's most obvious meteor impact structures with our Google Map of Meteor Impact Structures.

Labels: Meteor-Meteorite, Oceanography, Satellite-Images

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Chicxulub Crater Satellite Image by NASA

Here's how the story has been told for decades...

About 65 million years ago a large asteroid or comet impacted the northwest coastline of the Yucatan Peninsula, Mexico. This impact left a crater about 112 miles wide and ejecta from the impact was carried high into the atmosphere and spread around the Earth. This temporarily reduced the amount of incoming solar radiation received by Earth. The interruption in solar radiation was long enough for the food chain to collapse and accounted for one of the greatest extinctions in Earth's history. Many scientists believe that over 70 percent of Earth's species were pushed into extinction - including the dinosaurs.

Now, Princeton University paleontologist Gerta Keller, Thierry Adatte from the University of Neuchatel, Switzerland, along with Zsolt Berner and Doris Stueben from Karlsruhe University in Germany say that the Chicxulub impact event was just one of a series of events that stressed Earth's systems and led to one of the greatest mass extinctions in the history of our planet. These researchers believe that Chicxulub predates the extinction and that a much larger, and still unidentified, impact dealt the most important blow. Here's how they think this happened....

"Chicxulub, though violent, actually conspired with the prolonged and gigantic volcanic eruptions of the Deccan Flood Basalts in India, as well as with climate change, to nudge species towards the brink. They were then pushed over with a second large meteor impact."

Their research was funded by the National Science Foundation and more details can be found at the NSF Website.

Related content on Geology.com - Impact Crater Map

Labels: Dinosaurs, Meteor-Meteorite

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Location: Impact Crater Field

This is not a "news" item as it was published in 2004. We post it here because it is very interesting and many Geology.com visitors find our site via the Impact Crater Map.

Philippe Paillou and others report the discovery of what might be Earth's largest impact crater field, located in the in the Gilf Kebir region of southwestern Egypt. There they found at least 50 circular features using space-borne radar imaging that are thought to be of impact origin. They conducted field work, studying 13 of the craters, and support the impact origin based upon impact-related features such as shatter cones and planar fracturing of quartz grains. The impact structures are scattered across a 4500 square kilometer area and are thought to have formed by the break-up of one or more meteorites that broke apart upon entry into Earth's atmosphere.

If one reads Paillou's article, the coordinates and characteristics of the thirteen studied structures are provided in a table. Many of these structures can be clearly seen on the satellite images of Google Maps. Here is a link to Impact Structure #13 on Google Maps.

A very nice review of other crater fields (some not conclusively demonstrated to be of meteor impact origin) is included in the article. These include:
* Kaali Crater Group - Island of Saaremaa, Estonia
* Rio Cuarto Field - Central Argentina
* Campo del Cielo Crater Field - Argentina
* Macha Impact Crater Field - Yakutia, Russia
* Morasko Crater Field - Poland
* Odessa Crater Field - Texas
* Wabar Crater Field - Rub'al Khali Desert, Saudi Arabia
* Sikhote-Alin Strewn Field - Siberia
* Sirente Field - Abruzzo Region, Central Italy

Note added 12/20/2006: The meteor impact origin of these features is reconsidered by the authors of the original article. It is now one of two alternative hypotheses, the second of which is a hydrothermal vent complex. Journal of African Earth Sciences 46 (2006) 281-299.

Labels: Meteor-Meteorite

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Scientists from Case Western Reserve University, who have a strong track record recovering meteorites in Antarctica, have discovered that one of their specimens found in 2005 is a piece of Earth's Moon. The specimen was found by members of the U.S. Antarctic Search for Meteorites program on an icefield in the Miller Range of the Transantarctic Mountains, roughly 750 km from the South Pole. The lunar meteorite weighs 142.2 grams and is slightly larger than a golf ball. The specimen was broken to allow a close study of its composition and texture. Pieces of the specimen will be shared with scientists at research centers around the world.


The meteorite is a coarse-grained gabbro that is similar in composition to lunar basalts that fill the lunar maria. However, the large crystal size suggests that this rock cooled within the Moon's interior. The cube in the image is one cubic centimeter in size. Image by NASA's Johnson Space Center.


Polarized light photomicrograph of part of the lunar meteorite. The bright, highly fractured material is pyroxene and the smoothly textured dark gray material is maskelynite, a mineral formed from the vitrification of plagioclase by shock melting. Image by NASA's Johnson Space Center.

Read more about the Lunar Meteorite at the Case Western Reserve Blog.

Labels: Arctic-Antarctic, Meteor-Meteorite

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Meteorites are popular items with collectors of earth science specimens and we recently ran across a website selling a very large Campo del Cielo Meteorite - which is reported here as a matter of curiosity. This Campo del Cielo meteorite is a nickel-iron octahedrite that is 32 inches high, 27 inches wide and weighs about 924 pounds (steel display stand with wheels included).


Photo used with permission from BigMeteorite.com
Read more about this large meteorite for sale at BigMeteorite.com or buy it for only $65,000.


Map copyright by Geology.com and Map Resources.
* Campo del Cielo is an area in northern Argentina where numerous small impact craters and many meteorites have been found. Native people knew of these objects and believed that they fell from the sky. The meteorites are nickel-iron octahedrites that are thought to have fallen between 4000 and 6000 years ago. Read more about them at Meteorite Market.

Labels: Meteor-Meteorite

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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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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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Apophis, a 1000 foot wide asteroid will cross Earth's orbit on Sunday, April 13, 2036. Scientists estimate that it has one chance in about 6,250 of hitting the earth. Such an impact would yield one of the greatest natural disasters in human history. The impact would create a blast that is thousands of times more powerful than the largest atomic weapon. This would kill millions of people if the impact occurred near a populated area or create an enormous tsunami if the impact happend in the ocean.

Read more about the Apophis Asteroid at Topix.net.

Labels: Meteor-Meteorite

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Researchers from Boston University have discovered the remnants of the largest crater of the Great Sahara of North Africa which may have been formed by a meteorite impact tens of millions of years ago. Dr. Farouk El-Baz discovered the 31 km diameter crater while studying satellite images of the Western Desert of Egypt with his colleague, Dr. Eman Ghoneim, at BU's Center for Remote Sensing. The crater was named Kebira, meaning "large" in Arabic.

Image Courtesy of Boston University Center for Remote Sensing
Read more about the discovery at the Boston University Website.

Explore the impact structure yourself using Google Maps.

View dozens of impact structures with Geology.com's interactive impact map.

Labels: Meteor-Meteorite

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The Cascadia Meteorite Laboratory at Portland State University has a webpage that provides guidance in identifying a suspected meteorite. In summary they explain that meteorites are: 1) heavy, 2) frequently magnetic, 3) irregular in shape, 4) covered by a fusion coating, 5) solid and compact, and 6) different from other rocks in the area.

Screenshot from CMLVisit the CML website to learn more about Meteorite Identification.

Labels: Meteor-Meteorite

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Here is an interesting website that describes how meteorites can be found in the Sahara Desert. Lots of good photos and interesting stories.

website screenshotRead more about Sahara Desert Meteorite Prospecting.

Labels: Meteor-Meteorite

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An interesting article in the Jackson Hole Star Tribune by Jack Cox explains why meteorites are so hard to find - even when their fall is witnessed by many people. Also provided are references to additional websites where meteorite information can be seen.

Image by NASA - fragment of the Murchison Meteorite which fell in Austrailia, 1969Read about How To Find Meteorites at jacksonholestartrib.com.

Labels: Meteor-Meteorite

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An interesting article at Kansas.com describes how Steve Arnold, the meteorite hunter who recently found a 1400 pound meteorite, prospects for them. Arnold pays farmers up front for the right to go meteorite hunting on their fields.
Read this article on Meteorite Hunting at Kansas.com.

Labels: Meteor-Meteorite

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Steve Arnold discovered a 1400 pound oriented pallasite meteorite in a Kansas field near the town of Haviland.
Read about the Kansas Meteorite at Kansas.com

Labels: Meteor-Meteorite

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There is a very interesting article about the Avak impact crater at www.sitenews.us. It explains how this subsurface crater (buried under surface deposits) was discovered and has information about its role in trapping natural gas.

You can read the Avak impact crater article at the website - or visit our google maps page if you would like to explore interactive satellite images of impact sites.

Labels: Meteor-Meteorite

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MSN has a brief tutorial on how to observe the Leonid meteor shower.

View the How to Observe a Meteor Shower tutorial at the MSN website. And be sure to check out our interactive satellite images of Earth Impact Structures.

Labels: Meteor-Meteorite

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Explore some of the most visible meteor impact sites through maps and satellite images. Our meteor impact page allows you to learn about and view several from across the earth using Google Maps.

Image by Geology.com and Google MapsView our interactive Meteor Impact Sites.

Labels: Meteor-Meteorite, Satellite-Images

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The Vredefort Dome is Earth's largest and oldest clearly visible meteorite structure. It is approximately 250 kilometers in diameter and is thought to be about 2 billion years old. This South Africa location is one of 50 sites that have been nominated for World Heritage Site Status. Selected sites will be announced at the UNESCO World Heritage Conference next month. See our article on the Vredefort Dome to learn more.

South Africa already has six World Heritage sites: Robben Island in the Western Cape (prison buildings here symbolize the triumph of the human spirit, of freedom, and of democracy over oppression), the Cradle of Humankind in Gauteng and North West (includes the fossil hominid sites of Sterkfontein, Swartkrans and Kromdraai), the Greater St Lucia Wetland Park in KwaZulu-Natal (fluvial, marine and aeolian processes here have produced a variety of landforms, including coral reefs, long sandy beaches, coastal dunes, lake systems, swamps, and extensive reed and papyrus wetlands), the uKhahlamba Drakensberg Park in KwaZulu-Natal (rock art paintings made by the San people over a period of 4000 years); the Mapungubwe Cultural Landscape in Limpopo (once the largest kingdom in the African Subcontinent before it was abandoned in the 14th century); and the Cape Floral Region of the Western Cape (an area of enormous species diversity - less than 0.5% of the area of Africa but supports nearly 20% of the continent’s floral species).


Image created using NASA Landsat Geocover Data

Labels: Meteor-Meteorite

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