| Development of scientific analysis instruments and creasing research degree are creating vast data stores in geochemistry study that require new scientific methods to analyze and organize the data. Since these new instruments have extraordinary precision, the data quality is also rapidly improving. North China Craton as the nature laboratory of study magma activity, tectonic evolution and mineralization of East China, researchers has developed a great deal of geochemical study work and accumulated lots of high qualities geochemical data. How to effectively store, manage, share and reuse the existing geochemical data, especially in the North China Craton area? How to quickly and effectively analyze the existing geochemical data is an urgent problem in geology study of North China Craton, and it is also a common question for international geologists.The traditional methods of geochemical data management include: data file, electro-sheet, and database. It is only manage a small quantity of geochemical data that just using electro-sheet and data file methods, and it is difficult for data querying, share, and selecting. Mass of traditional database systems were build by scientific research institute on special subject that have many disadvantages: (1) lack intact geochemical data model and metadata information; (2) do not offer good visualization and just have few data analysis functions; (3) database operation is very complex. So traditional database systems have lagged in supporting scientific data management but they have a few things scientists desperately need for their data analysis.Scientific database is a method that applied the relational database, WebGIS and GIS technology to realize efficiently manage and share enormous data. Using scientific database, researchers can conveniently manage, query and analyze their science data. Scientific database offered a new method for geochemical data's scientific management, and using it to realize the geochemical data's sharing, getting and communication become a hot study in the international geochemical data management area. This thesis is about geochemical scientific data management of North China Craton with scientific database. The major objectives are: deeply study geochemical data's formation, composition and features; establish scientific, logical and integrated geochemical data model; applying the relational database, GIS and WebGIS, and Internet technology, establish the East China geochemical scientific database (NCGD). Using the NCGD database, researchers can query, analyze, output and implement spatial visualization to the geochemical data via a website; and study and establish new software for geochemical diagram plotting that solving the existing program's limits. So we will offer a new method for geochemical data management and efficient analysis, which is the urgent problem in geochemistry and relatively field.The research contents are: (1) Study of geochemical data's formation, composition and features. The integrated geochemical data not only include basic analysis data of rock samples, but also metadata, which is the descriptive information about data that explains the measured attributes, their names, units, precision, accuracy and ideally a great deal more. Most importantly, metadata includes the data lineage that describes how the data was measured, acquired or computed. Based on geochemical data's composition and features, and thinking about communicate with international research, we will select the necessary data sets and metadata for storing in geochemical data model.(2) Geochemical data model research. There are currently no standards for the submission of data and metadata, which substantially limits the utility of many data sets among different articles, reports and publications. No integrated and logical data model is a common question for existing geochemical database. In this thesis, base on the deeply study of geochemical data's composition and features, we will establish scientific, logical and integrated geochemical data model that use relational database theory and spatial database theory. All data that consist of analysis data, property information and metadata are stored in a series of relationship tables which have the unique name.(3) Establish the North China Craton scientific database. According to relational data model and geochemical data's contents, we will establish the North China Craton geochemical scientific database that apply the relational database, GIS and WebGIS , and Internet technology, which offered a new tool of geochemical data sharing and communication for geologists. In order to reduce the probability of data inputting failure, we will offer an Excel table model for users. The program automatic transfers the data into the database while users just need input the data into the Excel table model.(4) Geochemical data application research. Here major research the application of methods of exploring data analysis (EDA), exploring spatial data analysis (ESDA) and GCDPlot in geochemical data analysis. We will combine the EDA, ESDA techniques and GIS and data visualization techniques in North China Craton Scientific Database, and realize the functions of geochemical data spatial and specialty analysis. Then researchers can directly explore the relationship, pattern, and trend among different geochemical data and acquire the major characteristics of data, which is the basic information for deep research. The research content of geochemistry diagram plotting system is develop a new VBA program called "GCDPlot" for geochemical data plotting in Microsoft Excel that resolve the existing software's limits of difficulty operation, difficulty application and difficulty extension.Integrated detailed studies of the above contents lead to the following conclusions:(1) We have designed the integrated and effective geochemical relational data model and established geochemical relational database.Through analysis the geochemical data's contents and features, reference the existing data model of international and domestic geochemical database, and using relational theory and relational model, we have designed the scientific and logical geochemical data model that can directly used in database establishment. We have also established geochemical relational database based on the geochemical relational data model to store geochemical data.(2) Appling ArcIMS, relational database, server-based dynamic cache and Ajax technology, we have realized no-gap integration and amalgamation of geochemical scientific database and GIS technology, and resolved the question of geochemical data's online spatial query, spatial visualization and spatial analysis.First, using the method of integration ArcIMS into geochemical scientific database, the system realized no-gap amalgamation GIS functions that resolved the spatial questions of geochemical data's location, distributing and trending. Using the system, users can query the data based on sample's location; the search results can be labeled on digital map and can generate classification thematic maps. Second, the application of server-based dynamic cache and Ajax technology in development of ArcIMS effectively reduce the server loading, improve server efficiency and user experience.(3) We have introduced the EDA and ESDA techniques to geochemical data analysis research, studied useful methods of EDA and ESDA in geochemical data analysis. They are including: histogram, scatter plot, box-whisker plot, classification thematic maps, and the linkage between graphs and spatial characteristics. The combination of EDA, ESDA techniques and GIS, visualization, and spatial visualization realized the geochemical data's real time analysis. This is the first study that combines EDA, ESDA techniques and geochemical scientific database that offered a new data analysis method for researchers.(4) Based on the geochemical data model, we established the North China Craton geochemical science database (NCGD) that applied the relational database and WebGIS technology. NCGD is the first Web-based geochemical scientific database that integrated the functions of data retrieval, spatial visualization and online analysis, and it is provide a geochemical data sharing, access and exchange collaboration platform for researchers.Using the NCGD database, researchers can query, analyze, output and implement spatial visualization to the geochemical data via a website. Because integration of WebGIS technology, the query results can be mapped on digital map based on WebGIS and can generate classification thematic maps. Meanwhile, researchers can make online analysis for the query results that using offered geochemical diagrams.(5) We have developed a user-friendly, extensible program called "GCDPlot" for plotting geochemical discrimination diagrams. It was developed using the VBA language and runs under Microsoft Excel 2000 or later that resolved the existing software's limits of difficulty operation, difficulty application and difficulty extension.
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