Jeofizikkulubu | Geophysics

Jeofizikkulubu | Geophysics

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Neutral Buckminsterfullerene in the Diffuse Interstellar Medium
Emission of fullerenes in their infrared vibrational bands has been detected in space near hot stars....
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Protect funding for US earthquake early-warning system
Donald Trump’s proposed cuts to ShakeAlert puts the west coast at risk.
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A Warm or a Cold Early Earth? New Insights From a 3-D Climate-carbon Model
Oxygen isotopes in marine cherts have been used to infer hot oceans during the Archean with temperatures between 60 deg C (333 K) and 80...
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Radio Emission from the Exoplanetary System ε Eridani
As part of a wider search for radio emission from nearby systems known or suspected to contain extrasolar planets ϵ Eridani was observed by the...
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Neutral Buckminsterfullerene in the Diffuse Interstellar Medium
Emission of fullerenes in their infrared vibrational bands has been detected in space near hot stars....
Read More
Protect funding for US earthquake early-warning system
Donald Trump’s proposed cuts to ShakeAlert puts the west coast at risk.
Read More
A Warm or a Cold Early Earth? New Insights From a 3-D Climate-carbon Model
Oxygen isotopes in marine cherts have been used to infer hot oceans during the Archean with temperatures between 60 deg C (333 K) and 80...
Read More
Radio Emission from the Exoplanetary System ε Eridani
As part of a wider search for radio emission from nearby systems known or suspected to contain extrasolar planets ϵ Eridani was observed by the...
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Extraordinary storms caused massive Antarctic sea ice loss in 2016
Antarctic sea ice – frozen ocean water that rings the southernmost continent – has grown over the past few decades but declined sharply in late...
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Timing of formation of the Keketale Pb–Zn deposit, Xinjiang, Northwest China, Central Asian Orogenic Belt: Implications for the metallogeny of the South Altay Orogenic Belt
The Keketale is the largest Pb–Zn deposit in the volcano‐sedimentary Maizi Basin of the South Altay Orogenic Belt (AOB), Northwest China. The stratabound orebodies are...
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Discovery of Mesoproterozoic kimberlite from Dörbed Banner, Inner Mongolia and its tectonic significance
Porphyritic olivine kimberlitic breccia, discovered in the Dörbed Banner of Inner Mongolia, Western China, is referred to as Longtou Shan Kimberlite in our study. This...
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Petrogenesis and tectonic setting of the Shiduolong skarn Pb–Zn deposit in the East Kunlun Orogenic Belt: Constraints from whole‐rock geochemical, zircon U–Pb and Hf isotope analyses
The Shiduolong Pb–Zn deposit, located in the East Kunlun Orogenic Belt, is a medium‐scale skarn deposit (0.4 Mt metal reserves with a grade of 1.46% Pb...
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A volcanic trigger for the Late Ordovician mass extinction? Mercury data from south China and Laurentia

The Late Ordovician mass extinction (LOME), one of the five largest Phanerozoic biodiversity depletions, occurred in two pulses associated with the expansion and contraction of ice sheets on Gondwana during the Hirnantian Age. It is widely recognized that environmental disruptions associated with changing glacial conditions contributed to the extinctions, but neither the kill mechanisms nor the causes of glacial expansion are well understood. Here we report anomalously high Hg concentrations in marine strata from south China and Laurentia deposited immediately before, during, and after the Hirnantian glacial maximum that we interpret to reflect the emplacement of a large igneous province (LIP). An initial Hg enrichment occurs in the late Katian Age, while a second enrichment occurs immediately below the Katian-Hirnantian boundary, which marks the first pulse of extinction. Further Hg enrichment occurs in strata deposited during glacioeustatic sea-level fall and the glacial maximum. We propose that these Hg enrichments are products of multiple phases of LIP volcanism. While elevated Hg concentrations have been linked to LIP emplacement coincident with other Phanerozoic mass extinctions, the climate response during the LOME may have been unique owing to different climatic boundary conditions, including preexisting ice sheets. Our observations support a volcanic trigger for the LOME and further point to LIP volcanism as a primary driver of environmental changes that caused mass extinctions.