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Geological processes alter pore spaces over time, and their analysis can shed light on the dynamic fractal structure and fluid flow of rocks over time. This study presents experimental evidence to illustrate that the pore fractal structure evolves with sedimentation, carbonate cementation, clay growth, and dissolution. It examines, describes and characterizes a suite of core samples from the Gaotaizi oil layer of the second and third members of the Qingshankou Formation, Songliao Basin, China. The effects of mechanical compaction and other diagenesis effects on fractal pore structure on sedimentary rocks are discussed. A schematic diagram is proposed that describes the impacts of these diagenetic processes on fractal pore structure at the microscopic scale in sedimentary rocks. This work links the state of diagenetic alteration and fractal pore structure, which can guide practical applications such as predicting the permeability of sedimentary rocks. Key Points Evolution of fractal dimension with diagenesis was revealed Effects of diagenesis on fractal upper and lower limits were discussed Effect mechanism of fractal pore structure was revealed in sedimentary rocks Plain Language Summary Mechanical compaction or chemical alteration process will change the pore space of the rock, including pore size and grain-pore interface properties. We present the evidence that geological processes alter the “roughness” amplitude of grain-pore interface (fractal pore structure) in sedimentary rock, and discuss the evolutionary mechanism of the “roughness” amplitude of grain-pore interface. This work links the state of diagenetic alteration and fractal properties of rocks, which can guide practical applications such as predicting permeability of sedimentary rocks for any historical period.

The orebodies are hosted by the NW-SE trending, steeply NE-dipping and 1 000 m wide Ma'erkakuli ductile shear zone and associated secondary structures, which transect Middle and Lower Devonian metamorphic rocks of lower greenschist facies. Tectonic evolution of the ductile shear zone has involved five main deformation stages. At least eight multifacies quartz veins, each with its own characteristic geometry and mineral paragenesis, were formed in the evolution of the shear zone. Au mineralisation is divided into four stages, and two main ore-forming events are recognised, brittle-ductile deformation-related pyrite-quartz veins and the transition of strike-slip deformation to extension domain- related polymetallic quartz veins. Early mineralisation was related to large-scale sinistral strike-slip and late mineralisation resulted from post-collisional structural transition., The orebodies are hosted by the NW-SE trending, steeply NE-dipping and 1 000 m wide Ma'erkakuli ductile shear zone and associated secondary structures, which transect Middle and Lower Devonian metamorphic rocks of lower greenschist facies. Tectonic evolution of the ductile shear zone has involved five main deformation stages. At least eight multifacies quartz veins, each with its own characteristic geometry and mineral paragenesis, were formed in the evolution of the shear zone. Au mineralisation is divided into four stages, and two main ore-forming events are recognised, brittle-ductile deformation-related pyrite-quartz veins and the transition of strike-slip deformation to extension domain- related polymetallic quartz veins. Early mineralisation was related to large-scale sinistral strike-slip and late mineralisation resulted from post-collisional structural transition.