GIS-based Mineral Resources Assessment System And The BP Model For Metallogenic Prognosis

With the great development and wide application of spatial informational technologies, mineral resources assessment and metallogenic prognosis, an important branch of geosciences, is striding forward in the informational direction. Supported by the GIS technology, the research field of the mineral resources assessment and metallogenic prognosis is tending to develop Expert Systems of mineral deposit model by dealing with the temporal and spatial distribution of mineral resources and building quantitative models of multiple metallogenic information. Aiming at the three pivotal problems in research on mineral resources assessment with GIS about designing data models of geology, GIS technologies for extracting and integrating mineralizing information, synthetic assessment models of mineral resources, and being guided by the object-oriented programming theory, the GIS-based Mineral Resources Assessment system was developed with a user-friendly interface, perfect functions and an independent platform. The ActiveX technology, the functional component of GIS named MapObjects and the artificial neural network technology were adopted in the developing environment of Visual C++ to fulfill the system whose core modules of gridding partition, intelligentized extraction of geologic variables, spatial database management and BP model for metallogenic prognosis were developed emphatically.The universal process which was expressed in a computer software project with the object-oriented programming technology and methods was analyzed and concluded systematically for mineral resources synthetic assessment and metallogenic prognosis. Furthermore, the GIS-based Mineral Resources Assessment System was divided in detail after demand analysis and structural design into six functional modules: the files input module, gridding partition module, spatial analysis module, intelligentized extracion of geologic variables module, orientation prediction module and attribution management module.The functional component of GIS named MapObjects published by America ESRI Corporation was applied unprecedentedly in the development of mineral resources assessment systems, which make the system independent of basic GIS platform and transplantable. The GIS-based Mineral Resources Assessment System deals with vector data structure mainly. And its spatial analytic functions such as overlay analysis and buffer analysis that can be used to extract multiple variables and information from geologic bodies organized in map layers in point, line or polygon shape are in favor of discovering ore-forming factors, summarizing regional metallogenic regularities and constructing geologic metallogenic models. Users can use the system to customize sizes of grid units and partition digital maps in grid. And users can also use the module of intelligentized extraction of geologic variables to extract and integrate metallogenic information included in various geologic attributions of variables in order to quantify vector graphic data in numerical value.The DAO database access system was adopted to access and manage attribution data effectively in the GIS-based Mineral Resources Assessment System Based on a list control, a view was created to show users attribution data. Users can create or select dynamically a DAO data source when the system is in a running process to define an attribution data object for the application program Moreover, the system provides users some functions to browse, edit, query and manage attribute data.It is feasible and advantaged to apply a BP model, one of artificial neural networks, to evaluate synthetically mineral resources and do metallogenic prognoses. And a BP model formetallogenic prognosis can be constructed as the general algorithm of BP network was programmed. Users can create, design and manage BP models for metallogenic prognoses by interacting with a computer through a user-friendly interface. When BP models are taken advantage of to do mineral resources assessment and metallogenic prognoses, metallogenic informati...