Sublithospheric diamond ages and the supercontinent cycle.

Subduction related to the ancient supercontinent cycle is poorly constrained by mantle samples. Sublithospheric diamond crystallization records the release of melts from subducting oceanic lithosphere at 300-700 km depths and is especially suited to tracking the timing and effects of deep mantle processes on supercontinents. Here we show that four isotope systems (Rb-Sr, Sm-Nd, U-Pb and Re-Os) applied to Fe-sulfide and CaSiO inclusions within 13 sublithospheric diamonds from Juína (Brazil) and Kankan (Guinea) give broadly overlapping crystallization ages from around 450 to 650 million years ago.

Comment on "Discovery of davemaoite, CaSiO-perovskite, as a mineral from the lower mantle".

Tschauner . (Reports, 11 November 2021, p. 891) present evidence that diamond GRR-1507 formed in the lower mantle.

COVID-19 Acute Respiratory Distress Syndrome and Pulmonary Embolism: A Case Report of Nebulized Nitroglycerin and Systemic Thrombolysis For Right Ventricular Failure.

Background: Acute respiratory compromise caused by complications of COVID-19, such as acute respiratory distress syndrome (ARDS) or thromboembolic disease, is a complex syndrome with unique challenges in treatment. Management often requires time and intensive care through a multiprofessional, multispecialty approach. Initial management is particularly challenging within the limited-resource environment of the emergency department (ED).

Heavy iron in large gem diamonds traces deep subduction of serpentinized ocean floor.

Subducting tectonic plates carry water and other surficial components into Earth's interior. Previous studies suggest that serpentinized peridotite is a key part of deep recycling, but this geochemical pathway has not been directly traced. Here, we report Fe-Ni-rich metallic inclusions in sublithospheric diamonds from a depth of 360 to 750 km with isotopically heavy iron (δFe = 0.

Diamondites: evidence for a distinct tectono-thermal diamond-forming event beneath the Kaapvaal craton.

The petrogenesis and relationship of diamondite to well-studied monocrystalline and fibrous diamonds are poorly understood yet would potentially reveal new aspects of how diamond-forming fluids are transported through the lithosphere and equilibrate with surrounding silicates. Of 22 silicate- and oxide-bearing diamondites investigated, most yielded garnet intergrowths ( = 15) with major element geochemistry (i.e.