X-ray diffraction data, crystallographic information file, infrared spectra, and LA-ICP-MS depthprofiles of davemaoite

Calcium silicate perovskite, CaSiO3, 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 CaSiO3-perovskite as an approved
mineral (IMA2020-12a) 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.

钙钛矿型硅酸钙（Calcium silicate perovskite），化学式为CaSiO3，通常被认为是下地幔中地球化学意义最为关键的矿物相，因其能够富集在上地幔中的不相容元素，包括半衰期长于地球地质演化史的生热元素钍（thorium）与铀（uranium）。本研究报道的CaSiO3钙钛矿已被国际矿物学协会（IMA）批准为正式矿物，编号为IMA2020-12a，矿物名称为戴莫伟石（davemaoite）。该矿物的天然标本证实了下地幔内部存在成分不均一性。观测结果显示，戴莫伟石的晶体结构中除了容纳铀和钍之外，还可赋存钾元素。因此，戴莫伟石的区域与全球丰度会影响该矿物呈热力学稳定状态的深地幔的热收支平衡。