The interaction of trace elements, fluids and crystal defects plays a vital role in a crystalline material’s response to an applied stress. Fluid inclusions are typically known to facilitate crystal-plastic deformation in minerals. Herein we discuss a model of fluid hardening, whereby dislocations are pinned at fluid inclusions during crystal-plastic deformation, initiating pipe diffusion of trace elements from the fluid inclusions into crystal defects that leads to their stabilization and local hardening. We derive this hypothesis from atom probe tomography data of naturally deformed pyrite, combined with electron backscatter diffraction mapping, electron channelling contrast imaging and scanning transmission electron microscopy. The 2D and 3D micro- to nanoscale structural and chemical data reveal nanoscale fluid inclusions enriched in As, O, Na and K that are linked by As-enriched dislocations. Our efforts advance the understanding of the interplay between nanostructures and impurities during relatively low temperature deformation, which yields insight into the larger scale mass transfer processes on Earth.

微量元素，流体和晶体缺陷的相互作用在晶体材料对施加应力的响应中起着至关重要的作用。通常已知流体包裹体有助于矿物中的晶体塑性变形。在本文中，我们讨论了一种流体硬化模型，其中在晶塑性变形过程中将位错固定在流体夹杂物上，从而引发微量元素从流体包裹体到晶体缺陷的管道扩散，从而导致其稳定和局部硬化。我们从自然变形黄铁矿的原子探针层析成像数据，结合电子反向散射衍射图谱，电子通道对比成像和扫描透射电子显微镜得出这一假设。2D和3D微米级到纳米级的结构和化学数据揭示了富含As，O，Na和K通过富As位错链接。我们的努力增进了对相对低温变形期间纳米结构与杂质之间相互作用的理解，从而深入了解了地球上更大规模的传质过程。