Phanerozoic limestones are composed of low-Mg calcite microcrystals (i.e., micrite) that typically measure between 1 and 9 mu m in diameter. These microcrystals, which host most of the microporosity in subsurface reservoirs, are characterized by a variety of microtextures. Despite the overwhelming consensus that calcite microcrystals are diagenetic, the origin of the various textures is widely debated. The most commonly reported texture is characterized by polyhedral and rounded calcite microcrystals, which are interpreted to form via partial dissolution of rhombic microcrystals during burial diagenesis. A proposed implication of this model is that dissolution during burial is responsible for significant porosity generation. This claim has been previously criticized based on massbalance considerations and geochemical constrains. To explicitly test the dissolution model, a series of laboratory experiments were conducted whereby various types of calcites composed of rhombic and polyhedral microcrystals were partially dissolved under a constant degree of undersaturation, both near and far-from-equilibrium.
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机译：显生代石灰岩由低镁方解石微晶（即云母）组成，直径通常在 1 至 9 μ m 之间。这些微晶承载着地下储层中的大部分微孔隙，其特征在于各种微观纹理。尽管压倒性的共识是方解石微晶是成岩的，但各种纹理的起源仍存在广泛争议。最常报道的纹理特征是多面体和圆形方解石微晶，这些微晶被解释为在埋藏成岩作用过程中通过菱形微晶的部分溶解而形成。该模型的一个建议是，埋藏过程中的溶解是产生大量孔隙率的原因。基于质量平衡考虑和地球化学约束，这一说法以前曾受到批评。为了明确测试溶出模型，进行了一系列实验室实验，其中由菱形和多面体微晶组成的各种类型的方解石在恒定的不饱和度下部分溶解，包括接近平衡和远离平衡。
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