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Martian meteorite Northwest Africa 7034, nicknamed Black Beauty, weighs approximately 11 ounces. Photo: NASA

A Martian meteor found in northwestern Africa that is more than 4 billion years ago came from Mars, and bears the traces of the tumultuous creation of the red planet.

The chemical dating and analysis was performed by scientists at Lawrence Livermore National Laboratory, and is published in the journal Science Advances.

The 13 fragments of the sample, known as NWA 7034, were tested by incremental heating experiments and measuring the isotope traces from within the rock. Those elements include argon, uranium, plutonium and xenon.

The estimated age, based on the chronometry work at the Livermore Nobel Gas Lab, placed the rock at more than 4.3 billion years ago. That time frame matches previous estimated based on other elemental analyses, including that involving lead.

The Martian breccia, meaning it contains different rocks from the crust of Mars, and then mixed by heating, provides a kind of microcosm of the planet’s surface. It is heterogeneous like the whole planet itself, in that the northern and southern hemispheres are vastly different. The northern is made up of lowlands, while the southern is made up rugged mountains and volcanoes.

Previous theories have suggested that Mars turned out with a diversity of landscapes through internal processes, a single impact or a series of impacts.

The detailed analysis of the rocks indicates it was planetary pressure from within that created the meteor. The terrain that it was created from was subject to prolonged volcanic pressures between 1.7 and 1.3 billion years ago. Then, the rock was fused into its current structure about 200 million years ago, or less.

“This study demonstrates that multiple radioisotopic dating systems that are reset by different metamorphic processes can be used to tease out the thermal history of a sample over billions of years,” Bill Cassata, a cosmochemist at Lawrence Livermore and the lead author, said.

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