Breccia From Heaven

Brecciated NWA complete slice

This amazing NWA-something-or-other is a Ringwoodite-rich brecciated L6 chondrite from the hot desert. More than a few pieces similar to this were recovered a decade or more ago, but very few contain an oriented brecciation like this one.

 

Brecciated NWA

The curvature of the fragmentation is unusual given the extreme violence applied to this slice’s parent body in order to produce such breakage.

 

Brecciated NWA

Black shock veins and nickel-iron nodules surround many of the fragments. As I’ve noted before with breccias, this a geologic photograph of a impact forever preserving the record of its rough childhood.

 

Brecciated NWA

It’s interesting that the rectangular fragments have a similar form in many ways. I fancy it a small Stonehenge from space with blocks on blocks in ordered arcs.

 

Brecciated NWA

Like streets through a city, the shock veins mark the traffic lanes around the building and open space. Once flowing like rivers, the filler between fragments cemented position for billions of years until exposed to light only recently.

 

Until next time….

About the Author

Martin Horejsi
Dr. Martin Horejsi is a Professor of Instructional Technology and Science Education at The University of Montana. A long-time meteorite collector and writer, before publishing his column The Accretion Desk in The Meteorite Times, he contributed often and wrote the column From The Strewnfields in Meteorite Magazine. Horejsi is currently a monthly columnist in The Science Teacher, a journal by the National Science Teachers Association. Horejsi specializes in the collection and study of historic witnessed fall meteorites with the older, smaller, and rarer the better. Although his meteorite collection once numbered over a thousand pieces with near that many different locations, several large trades and sales have streamlined the collection to about 250 locations with all but 10 being important witnessed falls. Many of the significant specimens in Horejsi's collection are historic witnessed falls that once occupied prominence in the meteorite collections of Robert A. Haag, James Schwade, and Michael Farmer. Other important specimens were acquired through institutional trades including those from The Smithsonian Institution, Arizona State University, and other universities.
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