Application Of Fractal Models To Research Mineral Particles Surface Morphology

As a branch of nonlinear science,fractal theory has been widely applied to various fields of geosciences and made some significant achievements.Fractal model has also been demonstrated to be an effective and rapid tool to research the surface morphological characteristics of mineral particles.Therefore,this dissertation mainly uses Perimeter-Area model,box-counting fractal model and Number-Area model to study the surface morphology of magnetite particles.In this dissertation,the magnetite in Luoyang iron deposit of Fujian Province is taken as the research object,and systematic sampling is carried out at different distances from the rock mass.After the analysis of sampling position and petrography under the microscope,there are three different ore-forming stages divided from the samples.And according to the different observation scales,the samples are divided into two scales: BSE image and polished section image.Then using image processing method of ArcGIS to extract magnetite particles from different images,and to carry out research work based on the above fractal models.The P-A fractal model is used to quantify the irregularities of minerals,the box-counting fractal model reflects the growth and distribution of minerals in the spatial plane,and the N-A model is used to characterize the relationship between the number of mineral particles and their area,it is generally used to compare the area between different types of minerals.Based on above fractal models,the fractal characteristics of magnetite particle surface morphology and the temporal and spatial variation characteristics of fractal dimension are obtained,which shows that Luoyang iron deposit of Fujian Province was formed by multi-stage magmatichydrothermal fluids,it provides a strong explanation and evidence for the formation of skarn type Fe-rich deposits.In addition,the box-counting dimension of magnetite particles reflects that the main type of ore-forming fluid in Luoyang iron deposit is magma,and the fluid flows linearly from rock mass to surrounding rock and metasomatism surrounding rock.This dissertation discusses the evolution of ore-forming fluid in Luoyang iron deposit by studying the surface morphological characteristics of magnetite particles,and the relevant conclusions are consistent with geological observation and geochemical research.It provides a new direction for the study of ore deposits,which is mainly based on the geochemistry of ore deposits,and expands the research field of ore deposits.