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Categories: Anthropology: Cultures, Geoscience: Geology
Published New clues about the rise of Earth's continents
(via sciencedaily.com) Original source New research deepens the understanding of Earth's crust by testing and ultimately eliminating one popular hypothesis about why continental crust is lower in iron and more oxidized compared to oceanic crust. The iron-poor composition of continental crust is a major reason why vast portions of the Earth's surface stand above sea level as dry land, making terrestrial life possible today. The study uses laboratory experiments to show that the iron-depleted, oxidized chemistry typical of Earth's continental crust likely did not come from crystallization of the mineral garnet, as a popular explanation proposed in 2018.
Published Research reveals longstanding cultural continuity at oldest occupied site in West Africa
(via sciencedaily.com) Original source Stone tools recovered from near the Senegalese coast extend occupation of the region back to 150 thousand years ago and are comparable to those seen across Africa at this time, but uniquely persist in the region until 10 thousand years ago.
Published Scientists recover an ancient woman's DNA from a 20,000-year-old pendant
(via sciencedaily.com) Original source An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.
Published Searching for ancient bears in an Alaskan cave led to an important human discovery
(via sciencedaily.com) Original source Genetic analysis links 3,000-year-old bone found in cave to modern Alaska Natives.
Published Long distance voyaging among the Pacific Islands
(via sciencedaily.com) Original source An international team of researchers has used geochemical fingerprinting to reconstruct long-distance voyages between central and western Pacific Islands during the last millennium A.D.
Published Ridgecrest faults increasingly sensitive to solid Earth tides before earthquakes
(via sciencedaily.com) Original source Faults in the Ridgecrest, California area were very sensitive to solid earth tidal stresses in the year and a half before the July 2019 Ridgecrest earthquake sequence.
Published Turkey's next quake: Research shows where, how bad -- but not 'when'
(via sciencedaily.com) Original source Using remote sensing, geophysicists have documented the massive Feb. 6 quake that killed more than 50,000 people in Eastern Turkey and toppled more than 100,000 buildings. Alarmingly, researchers found that a section of the fault remains unbroken and locked -- a sign that the plates there may, when friction intensifies, generate another magnitude 6.8 earthquake when it finally gives way.
Published Plate tectonic processes in the Pacific and Atlantic during the Cretaceous period have shaped the Caribbean region to this day
(via sciencedaily.com) Original source Earthquakes and volcanism occur as a result of plate tectonics. The movement of tectonic plates themselves is largely driven by the process known as subduction. The question of how new active subduction zones come into being, however, is still under debate. An example of this is the volcanic Lesser Antilles arc in the Caribbean. A research team recently developed models that simulated the occurrences in the Caribbean region during the Cretaceous, when a subduction event in the Eastern Pacific led to the formation of a new subduction zone in the Atlantic. The computer simulations show how the collision of the old Caribbean plateau with the Greater Antilles arc contributed to the creation of this new Atlantic subduction zone. Some 86 million years ago, the triggered processes subsequently resulted in a major mantle flow and thus to the development of the Caribbean large igneous province.
Published How did the Andes Mountains get so huge? A new geological research method may hold the answer
(via sciencedaily.com) Original source How did the Andes -- the world's longest mountain range -- reach its enormous size? This is just one of the geological questions that a new method may be able to answer. With unprecedented precision, the method allows researchers to estimate how Earth's tectonic plates changed speed over the past millions of years.
Published How did Earth get its water?
(via sciencedaily.com) Original source Our planet's water could have originated from interactions between the hydrogen-rich atmospheres and magma oceans of the planetary embryos that comprised Earth's formative years.
Published Humans need Earth-like ecosystem for deep-space living
(via sciencedaily.com) Original source Can humans endure long-term living in deep space? The answer is a lukewarm maybe, according to a new theory describing the complexity of maintaining gravity and oxygen, obtaining water, developing agriculture and handling waste far from Earth.
Published Critical observations of sinking coasts
(via sciencedaily.com) Original source Using satellite-obtained data from 2007-21, researchers mapped the entire East Coast to demonstrate how the inclusion of land subsidence reveals many areas to be more vulnerable to floods and erosion than previously thought.
Published Study re-evaluates hazards and climate impacts of massive underwater volcanic eruptions
(via sciencedaily.com) Original source Material left on the seafloor by bronze-age underwater volcanic eruptions is helping researchers better understand the size, hazards and climate impact of their parent eruptions, according to new research.
Published Lightning strike creates phosphorus material
(via sciencedaily.com) Original source A lightning strike in New Port Richey, Florida, led to a chemical reaction creating a new material that is transitional between space minerals and minerals found on Earth. High-energy events, such as lightning, can cause unique chemical reactions. In this instance, the result is a new material -- one that is transitional between space minerals and minerals found on Earth.
Published Warm liquid spewing from Oregon seafloor comes from Cascadia fault, could offer clues to earthquake hazards
(via sciencedaily.com) Original source Oceanographers discovered warm, chemically distinct liquid shooting up from the seafloor about 50 miles off Newport. They named the unique underwater spring 'Pythia's Oasis.' Observations suggest the spring is sourced from water 2.5 miles beneath the seafloor at the plate boundary, regulating stress on the offshore subduction zone fault.
Published Was plate tectonics occurring when life first formed on Earth?
(via sciencedaily.com) Original source Researchers used small zircon crystals to unlock information about magmas and plate tectonic activity in early Earth. The research provides chemical evidence that plate tectonics was most likely occurring more than 4.2 billion years ago when life is thought to have first formed on our planet. This finding could prove beneficial in the search for life on other planets.
Published Researchers use 21st century methods to record 2,000 years of ancient graffiti in Egypt
(via sciencedaily.com) Researchers are learning more about ancient graffiti -- and their intriguing comparisons to modern graffiti -- as they produce a state-of-the-art 3D recording of the Temple of Isis in Philae, Egypt.
Published Ancient DNA reveals Asian ancestry introduced to East Africa in early modern times
(via sciencedaily.com) The largest-yet analysis of ancient DNA in Africa, which includes the first ancient DNA recovered from members of the medieval Swahili civilization, has now broken the stalemate about the extent to which people from outside Africa contributed to Swahili culture and ancestry.
Published Surprise effect: Methane cools even as it heats
(via sciencedaily.com) Most climate models do not yet account for a recent discovery: methane traps a great deal of heat in Earth's atmosphere, but also creates cooling clouds that offset 30% of the heat.
Published Giant volcanic 'chain' spills secrets on inner workings of volcanoes
(via sciencedaily.com) Volcanic relics scattered throughout the Australian landscape are a map of the northward movement of the continent over a 'hotspot' inside the Earth, during the last 35 million years.