Calcium silicate perovskite, CaSiO, is arguably the most geochemically important phase in the lower mantle, because it concentrates elements that are incompatible in the upper mantle, including the heat-generating elements thorium and uranium, which have half-lives longer than the geologic history of Earth. We report CaSiO-perovskite as an approved mineral (IMA2020-012a) with the name davemaoite. The natural specimen of davemaoite proves the existence of compositional heterogeneity within the lower mantle. Our observations indicate that davemaoite also hosts potassium in addition to uranium and thorium in its structure. Hence, the regional and global abundances of davemaoite influence the heat budget of the deep mantle, where the mineral is thermodynamically stable.

Download full-text PDF

Source
http://dx.doi.org/10.1126/science.abl8568DOI Listing

Publication Analysis

Top Keywords

lower mantle
12
mantle
5
discovery davemaoite
4
davemaoite casio-perovskite
4
casio-perovskite mineral
4
mineral lower
4
mantle calcium
4
calcium silicate
4
silicate perovskite
4
perovskite casio
4

Similar Publications

Seismic tomographic models based only on wave velocities have limited ability to distinguish between a thermal or compositional origin for Earth's 3D structure. Complementing wave velocities with attenuation observations can make that distinction, which is fundamental for understanding mantle convection evolution. However, global 3D attenuation models are only available for the upper mantle at present.

View Article and Find Full Text PDF

Residual heavy metals and antibiotic pollution in abandoned breeding areas along the northeast coast of Hainan Island, China.

Mar Pollut Bull

January 2025

Anhui Province Key Laboratory of Polar Environment and Global Change, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China; CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China. Electronic address:

To assess the environmental status of an abandoned aquaculture and breeding area in the northeast coast of the Hainan Island, surface and well water, sediment and surface soils were sampled and analyzed for conventional physicochemical properties, heavy metals and antibiotics. Metagenome tests were also conducted to determine the composition and diversity of the microbial community in typical habitats. Affected by the discharge of wastewater from higher-place pond aquaculture, coastal freshwater rivers have undergone significant salinization, Cl and Na were as high as 4.

View Article and Find Full Text PDF

The return of stagnant slab recorded by intraplate volcanism.

Proc Natl Acad Sci U S A

January 2025

State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China.

Subducted plates often stagnate in the mantle transition zone (MTZ), and the fate of the stagnant slabs is still debatable. They may sink into the lower mantle, or remain partially trapped in the MTZ, but it is uncertain whether they can return to the upper mantle. We report geochemical evidence of late-Miocene (~6 Ma) basalts from, and upper mantle seismic evidence beneath Shuangyashan, an area above the slab tear of the stagnant Pacific plate in eastern Asia, to show how the slab returns to the upper mantle from the MTZ.

View Article and Find Full Text PDF

In the eastern segment of the Central Asian Orogenic Belt (CAOB), there is widespread volcanic magma activity. However, there is still considerable controversy over the formation mechanisms and material sources of these volcanoes. The mantle transition zone (MTZ), as a necessary channel for the upward and downward movement of mantle material and energy exchange may provide crucial constraints on the dynamic mechanisms of volcanic activity.

View Article and Find Full Text PDF

Infected Primary Bone Mantle Cell Lymphoma with Multiple Vertebral Involvement.

Int J Hematol Oncol Stem Cell Res

October 2024

Department of Endocrinology and Internal Medicine, Tahar Sfar University Hospital, Mahdia, Tunisia.

Primary vertebral lymphoma is an exceedingly rare entity. We hereby report a case of a 67-year-old male who presented to our department with fever, weight loss, and progressively worsening lower back pain radiating to the right hip. Physical examination showed pain on percussion of the dorsal and lumbar spine and tenderness on palpation of the right upper thigh area.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!