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Call it extraterrestrial bling. Fossilised sea creatures have been found that coated themselves in tiny diamonds created in the asteroid impact that killed off the dinosaurs.
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The asteroid presumed to have wiped out the dinosaurs struck the Earth with such force that carbon deep in the Earth's crust liquefied, rocketed skyward, and formed tiny airborne beads that blanketed the planet, say scientists from the U.S., U.K., Italy, and New Zealand in this month's Geology.
The beads, known to geologists as carbon cenospheres, cannot be formed through the combustion of plant matter, contradicting a hypothesis that the cenospheres are the charred remains of an Earth on fire. If confirmed, the discovery suggests environmental circumstances accompanying the 65-million-year-old extinction event were slightly less dramatic than previously thought.

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Imagine the asteroid impact that killed off the dinosaurs and you may also picture a hellish aftermath of global forest fires. However, soot particles from across the globe now suggest that the smoke that shrouded the world after the collision came from immature oil in rocks at the crater site.
Over 20 years ago, researchers found large volumes of soot in the distinctive layer of iridium-rich sediment that marks the impact, 65 million years ago. Theory had it that the rock from the crater was vaporised, and that the soot came from extensive wildfires sparked by the smash. However, charcoal from burnt plant material is absent in some places, suggesting the fires were not global.

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The meteorite linked to the mass extinction of dinosaurs and other life forms 65 million years ago was four to six kilometres in diameter. Thats the conclusion of a team of Hawaii University researchers who have evolved a mechanism to measure the size of meteorites that have rammed into earth over millennia.
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Chicxulub
1996 (black) and 2005 (red) seismic surveys are shown over the Bouguer gravity anomaly map showing the buried Chicxulub impact crater. The black dots are cenotés, the black star is the crater centre and the white line is the coastline. The black dashed line shows the extent of the Cenozoic Chicxulub basin. Faults in the rings (white) can be traced to the near surface, whereas faults in the terrace zone (grey) are buried by breccia. Radial distances to distinct features, such as the start of the ring faults, vary by up to 20 km. .

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Title: Importance of pre-impact crustal structure for the asymmetry of the Chicxulub impact crater
Authors: Sean P. S. Gulick, Penny J. Barton, Gail L. Christeson, Joanna V. Morgan, Matthew McDonald, Keren Mendoza-Cervantes, Zulmacristina F. Pearson, Anusha Surendra, Jaime Urrutia-Fucugauchi, Peggy M. Vermeesch & Mike R. Warner

Impact craters are observed on the surfaces of all rocky planets and satellites in our Solar System; some impacts on Earth, such as the Cretaceous/Tertiary one that formed the Chicxulub impact crater, have been implicated in mass extinctions. The direction and angle of the impactor its trajectoryis an important determinant of the severity of the consequent environmental damage, both in the downrange direction (direction bolide travels) and in the amount of material that enters the plume of material vaporised on impact. The trajectory of the Chicxulub impact has previously been inferred largely from asymmetries in the gravity anomalies over the crater. Here, we use seismic data to image the Chicxulub crater in three dimensions and demonstrate that the strong asymmetry of its subsurface correlates with significant pre-existing undulations on the end-Cretaceous continental shelf that was the site of this impact. These results suggest that for rocky planets, geological and geomorphological heterogeneities at the target site may play an important role in determining impact crater structure, in addition to impact trajectories. In those cases where heterogeneous targets are inferred, deciphering impact trajectories from final crater geometries alone may be difficult and require further data such as the distribution of ejecta.

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The most detailed three-dimensional seismic images yet of the Chicxulub crater, a mostly submerged and buried impact crater on the Mexico coast, may modify a theory explaining the extinction of 70 percent of life on Earth 65 million years ago.
The Chicxulub crater was formed when an asteroid struck on the coast of the Yucatan Peninsula. Most scientists agree the impact played a major role in the "KT Extinction Event" that caused the extinction of most life on Earth, including the dinosaurs.
According to Sean Gulick, a research scientist at the Institute for Geophysics at The University of Texas at Austin's Jackson School of Geosciences and principal investigator for the project, the new images reveal the asteroid landed in deeper water than previously assumed and therefore released about 6.5 times more water vapour into the atmosphere.

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K-T boundary
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Splashing through a shallow creek in suburban New Jersey, the palaeontologists stepped back 65 million years to the time of the last mass extinction, the one notable for the demise of the dinosaurs.
The stream flows over sediment laid down toward the end of geologys Cretaceous period. The clay at water level holds meaningful traces of iridium, the element more common in asteroids and other extraterrestrial objects than in the earth. No one could resist sticking a finger to the clay, treating it as a touchstone of their time travel.
Scientists associate the iridium anomaly with the asteroid impact or impacts thought to have set off the extinctions. The thin layer, which has been detected worldwide, is also considered the marker for the end of the Cretaceous and beginning of the Tertiary period, known as the K-T boundary.

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