Surface energy and strain effects on calcite dissolution

我们的目标是确定实验的表面反应性（在相对于解理面的表面的取向方面）以及应力（弹性应变和塑性变形）对方解石溶解的机制和速率的影响。使用的技术将是：原位流体池原子力显微镜（AFM）、垂直扫描干涉仪（VSI）和透射电子显微镜（TEM）。我们将研究方解石单晶表面的溶解和表面重组抛光与不同的错切角（例如，5°、10°、20°）。将确定流体的饱和状态的影响。弹性应变的作用将确定使用一种新开发的微弯曲方法应力方解石和石膏的单晶体的弹性极限，没有脆性破坏，在流体细胞的AFM。塑性变形对溶解机制的影响将作为流体饱和度的函数进行研究。TEM将用于表征样品的表面重构、位错结构以及由样品制备或施加应力引起的缺陷。

The objective is to determine experimentally the effect of surface reactivity (in terms of the orientation of the surface relative to a cleavage plane) as well as stress (elastic strain and plastic deformation) on the mechanisms and rates of calcite dissolution. The techniques used will be: in-situ fluid-cell Atomic Force Microscopy (AFM) .Vertical Scanning Interferometry (VSI) and Transmission Electron Microscopy (TEM). We will study the dissolution and surface reorganisation of calcite single-crystal surfaces polished with varying miscut angles (e.g., 5°, 10°, 20°) to the cleavage planes. The effect of the saturation state of the fluid will be determined. The role of elastic strain will be determined using a newly developed microbending method to stress single-crystals of calcite and gypsum up to the elastic limit, without brittle failure, within the fluid cell of an AFM. The effect of plastic deformation on the dissolution mechanism will be studied as a function of fluid saturation. TEM will be used to characterise surface reconstruction, dislocation structure of the samples, and defects caused by sample preparation or by the applied stress.