The upper mantle is critical for our understanding of terrestrial magmatism, crust formation, and element cycling between Earth’s solid interior, hydrosphere, atmosphere, and biosphere. Mantle composition and evolution have been primarily inferred by surface sampling and indirect methods. We recovered a long (1268-meter) section of serpentinized abyssal mantle peridotite interleaved with thin gabbroic intrusions. We find depleted compositions with notable variations in mantle mineralogy controlled by melt flow. Dunite zones have predominantly intermediate dips, in contrast to the originally steep mantle fabrics, indicative of oblique melt transport. Extensive hydrothermal fluid-rock interaction is recorded across the full depth of the core and is overprinted by oxidation in the upper 200 meters. Alteration patterns are consistent with vent fluid composition in the nearby Lost City hydrothermal field.

中文翻译：

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长段蛇纹石化贫化地幔橄榄岩


上地幔对于我们理解陆地岩浆作用、地壳形成以及地球固体内部、水圈、大气和生物圈之间的元素循环至关重要。地幔组成和演化主要通过表面采样和间接方法推断。我们发现了一段长（1268 米）的蛇纹石化深海地幔橄榄岩，其中夹杂着薄薄的辉长岩侵入体。我们发现贫化成分在受熔体流动控制的地幔矿物学中具有显着变化。纯铜岩带主要具有中间倾角，与最初陡峭的地幔结构相反，表明倾斜熔体输送。整个岩心深度都记录了广泛的热液流体-岩石相互作用，并在上部 200 米处被氧化所覆盖。蚀变模式与附近失落之城热液田的喷口流体成分一致。