Ancient Cosmic Dust from Triassic Halite
نویسندگان
چکیده
Introduction: Until now micrometeorites have been extracted from limited periods of geological time (up to ~185-Myr-old) providing only a fragmented record of MM flux changes over geological time [1]. Because of preservation problems, we did not think MMs could be recovered from salt deposits (such as halite). Here we report that not only can MMs be found in, and successfully extracted from, halite; they can also provide an estimate of the terrestrial micrometeorite flux. We found that during the Anisian age of the Triassic (~236-239 Myr ago/Ma) the estimated flux of material in a limited size range was much lower than present day. Our results demonstrate that global salt deposits may provide reservoirs of abundant MMs, spanning a larger degree of geological time than we currently have flux data for. Therefore, the systematic extraction of MMs from salt deposits worldwide will provide the opportunity of tracing cosmic dust flux throughout geological time.
منابع مشابه
Cosmic Spherules from Triassic Deep-sea Sediments in Japan
Introduction: Cosmic spherules are subspherical to spherical particles of <1 mm diameter which are produced by melting of interplanetary dust and large objects during atmospheric entry. Although cosmic spherules are known principally from the ice sheets of polar regions and Cenozoic deep-sea sediments [1-3], a few spherules older than Mesozoic were recovered from the sedimentary rocks of pelagi...
متن کاملOrigin of deformed halite hopper crystals, pseudomorphic anhydrite cubes and polyhalite in Alpine evaporites (Austria, Germany).
The Alpine Haselgebirge Formation represents an Upper Permian to Lower Triassic evaporitic rift succession of the Northern Calcareous Alps (Eastern Alps). Although the rocksalt body deposits are highly tectonised, consisting mainly of protocataclasites and mylonites of halite and mudrock, the early diagenetic history can be established from non-tectonised mudrock bodies: Cm-sized euhedral halit...
متن کاملDraft Genome Sequence of Staphylococcus succinus Strain CSM-77, a Moderately Halophilic Bacterium Isolated from a Triassic Salt Mine
Here, we report the draft genome sequence of Staphylococcus succinus strain CSM-77. This moderately halophilic bacterium was isolated from the surface of a halite sample obtained from a Triassic salt mine.
متن کاملMicroscopic identification of prokaryotes in modern and ancient halite, Saline Valley and Death Valley, California.
Primary fluid inclusions in halite crystallized in Saline Valley, California, in 1980, 2004-2005, and 2007, contain rod- and coccoid-shaped microparticles the same size and morphology as archaea and bacteria living in modern brines. Primary fluid inclusions from a well-dated (0-100,000 years), 90 m long salt core from Badwater Basin, Death Valley, California, also contain microparticles, here i...
متن کاملAncient Microbes from Halite Fluid Inclusions: Optimized Surface Sterilization and DNA Extraction
Fluid inclusions in evaporite minerals (halite, gypsum, etc.) potentially preserve genetic records of microbial diversity and changing environmental conditions of Earth's hydrosphere for nearly one billion years. Here we describe a robust protocol for surface sterilization and retrieval of DNA from fluid inclusions in halite that, unlike previously published methods, guarantees removal of poten...
متن کامل