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Phanerozoic limestones are composed of low-Mg calcite microcrystals (i.e., micrite) that typically measure between 1 and 9 μm 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 mass-balance 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. Our results indicate that calcite crystals dissolved under far-from-equilibrium conditions develop rounded edges and corners, inter-crystal gulfs (narrow grooves or channels between adjacent crystals), and a few etch pits on crystal faces—observations consistent with the burial-dissolution hypothesis. Crystals dissolved under near-equilibrium conditions, in contrast, retain sharp edges and corners and develop ledges and pits—suggesting that dissolution occurs more selectively at high-energy sites. These observations support the longstanding understanding that far-from-equilibrium dissolution is transport-controlled, and near-equilibrium dissolution is surface-controlled. Our results also show that while the rhombic calcite crystals may develop rounded edges and corners when dissolved under far-from-equilibrium conditions the crystals themselves do not become spherical. By contrast, polyhedral crystals not only develop rounded edges and corners when dissolved under far-from-equilibrium conditions but become nearly spherical with continued dissolution. Collectively, these observations suggest that rounded calcite microcrystals more likely form from a precursor exhibiting an equant polyhedral texture, rather than from a euhedral rhombic precursor as previously proposed. Lastly, the observation that calcite crystals developed rounded edges and corners and inter-crystal gulfs after only 5% dissolution indicates that the presence of such features in natural limestones need not imply that significant porosity generation has occurred.

Breast cancer is the biggest cause of mortality in women, outscoring all other malignancies. Diagnosing breast cancer is hard because the disease is complicated, treatment methods change, and there are many different kinds of patients. Information technology and artificial intelligence contribute to improve diagnostic procedures, which are critical for care and treatment as well as reducing and controlling cancer recurrence. The primary part of this research is to develop a new feature selection strategy based on a hybrid approach that combines two methods for selecting features: the filter and the wrapper. In two stages, this method reduces the number of features from 30 to 15 to increase and improve classification accuracy. The suggested method was tested using the Wisconsin Breast Cancer Dataset dataset (WDBC). To enhance the classification of breast cancer tumors, a soft voting classifier was used in this study. The proposed methodology outperforms previous research, achieving 1 for the F1 score, 1 for AUC, 1 for recall, 1 for precision, and 100% for accuracy. Furthermore, 10-fold cross-validation has a 98.2% accuracy rate.