Comparative Analysis of Sedimentary Fabric in Coastal and Inland Basins

Thesis Abstract

Sedimentary fabrics encapsulate critical insights into depositional processes, facies differentiation, and paleoenvironmental reconstructions, yet comparative analyses between coastal and inland basin settings remain underexplored in contemporary geological research. This study aims to systematically evaluate and contrast the sedimentary fabric characteristics of coastal versus inland basins to elucidate depositional mechanisms, sediment supply influences, and diagenetic alterations unique to each environment. The specific objectives include identifying key sedimentary fabric parameters, assessing their spatial variability, and developing a conceptual model that integrates sedimentological processes across both basin types. Employing a comparative research design, this study adopts a mixed-methods approach. The population encompasses sedimentary rock units from two well-documented basins—comprising 50 stratigraphic sections, equally divided between coastal and inland settings within a defined geological framework. A stratified random sampling technique was employed to select representative outcrops and core samples, ensuring spatial heterogeneity is adequately captured. Data collection involved detailed petrographic thin-section analysis, granulometric assessments, and measurement of fabric elements such as grain orientation, packing, and layering using high-resolution scanning electron microscopy (SEM) and image analysis software. To facilitate comprehensive understanding, the study integrates qualitative and quantitative data. Petrographic and SEM imagery were analyzed through stereological techniques to quantify orientation distributions and fabric anisotropy, while granulometric data were subjected to multivariate statistical analyses including principal component analysis (PCA) to identify dominant controls on sediment fabric development. The applicability of sedimentological theories such as the turbidity current theory and the hydrodynamic sorting model was evaluated through regression analyses, with hypotheses tested via ANOVA to determine significant differences in fabric characteristics between basin types. The study also applies tectonostratigraphic models to contextualize depositional environments and diagenetic evolution. Expected findings anticipate discernible differences in the sedimentary fabric signatures, with coastal basins exhibiting more organized, laminar fabrics influenced by high-energy depositional processes and wave reworking, whereas inland basins are expected to show more chaotic, poorly sorted fabrics indicative of low-energy, fluvial or lacustrine environments. Variations in grain orientation, spacing, and fabric anisotropy are projected to correlate positively with depositional energy and sediment supply rates, offering a robust basis for a comparative model. This research contributes novel insights into basin-scale sedimentology by providing an integrated framework for interpreting sedimentary fabrics across diverse depositional environments. By elucidating the fundamental depositional controls and diagenetic influences on sediment architecture, the findings will enhance depositional modeling, basin analysis, and hydrocarbon exploration strategies. The main conclusion underscores the substantial variation in sedimentary fabric attributes driven by environmental energy regimes, sediment supply, and post-depositional alterations. Recommendations include incorporating sedimentary fabric analysis into routine basin characterization workflows and extending the comparative approach to other geological settings for broader generalization. Future research avenues suggested involve high-resolution three-dimensional imaging and isotopic analyses to refine interpretations of depositional dynamics and diagenetic processes influencing sedimentary fabric evolution.