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Abstract: Growing macroscale fold structures are one of the most dynamic and complex systems in geology, where during fold growth pore fluid pressure, fluid temperature, and fluid composition (PTX) conditions do not remain static but instead vary continually at all points within the deforming fold such that no two points within the fold will have the same deformation or fluid history. These PTX conditions in turn directly affect fluid storage and mobility as well as rock strength, which has direct feedback on the mechanical development of the fold. In this review, we first outline the research methodologies that have yielded significant insights, and review four examples of well-constrained fold-related fluid systems. We then discuss the fluid-related, fold-related, and mesoscopic deformation processes that are relevant to fold-related fluid systems. Finally, we close by presenting several conceptual models for fold-related fluid system structure, and highlighting key areas for future work. [Copyright &y& Elsevier]

This review paper examines deformation adjacent to salt stocks and walls and beneath salt sheets, with a focus on passive salt rise or emplacement and structures ranging from large-scale folds and faults to small-scale folds, fractures, and shear zones. The analysis begins with a summary of the existing literature on physical and numerical modeling and empirical subsurface and outcrop data, which offer conflicting interpretations and models. The emphasis here, however, is on exposed diapirs and sheets in a variety of salt basins. These demonstrate that near-salt deformation during passive diapirism is less common and less pronounced than is typically thought. In most cases, diapir rise and sheet emplacement do not directly shear and fracture adjacent strata. Instead, salt movement leads to drape folding of a thin roof, which in turn may cause associated fracturing, just as with folding of any origin. There can be exceptions, with the most common being regional extensional, contractional, or strike-slip deformation that is coeval with or postdates diapirism. This is especially the case if the salt becomes welded and there is ongoing weld-parallel slip or if fault damage zones formed away from diapirs subsequently become juxtaposed against the salt by ongoing slip. • Outcrop data are critical for testing models of near-salt deformation. • Diapir growth and sheet emplacement do not cause shear/drag of adjacent rock. • Passive diapirism generates drape folding of roof strata and associated fracturing. • Excess deformation is caused by regional stresses or other anomalies. [ABSTRACT FROM AUTHOR]