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SHRIMP and LA–ICP–MS zircon U–Pb dating, Nd and Hf isotope analyses, 40Ar/39Ar geochronology, and whole‐rock geochemistry indicate three episodes of magmatism in the Dabaoshan ore district, South China: (1) Caledonian dacites (ca. 438 Ma); (2) Indosinian dolerites (ca. 210 Ma); and (3) Yanshanian granodiorites/porphyries (ca. 165 Ma) and basalts (ca. 147 Ma). Episode 1 dacites and episode 3 granodiorites/porphyries are enriched in Rb, Th, U, and LREEs and depleted in Nb, Ta, Sr, P, and Ti. The dacites may have been derived from partial melting of Mesoproterozoic–Paleoproterozoic crustal material, whereas the granodiorites/porphyries were derived mainly from partial melting of a late Mesoproterozoic crustal source with minor inputs of mantle material, according to whole‐rock εNd(t) and zircon εHf(t) values. The geochemical characteristics of episode 2 dolerites and episode 3 basalts, as well as their positive εNd(t) values (3.3–5.9 and 3.5–4.0, respectively), suggest a depleted mantle source. Taking into account the tectonic evolution of the South China Block, we suggest episode 1 dacites and episode 2 dolerites formed in an extensional setting that resulted from lithospheric delamination during the Caledonian intraplate orogeny and orogenic collapse during the Indosinian intraplate orogeny. Episode 3 granodiorites/porphyries and basalts formed in a back‐arc extensional setting in response to the westwards subduction of the Palaeo‐Pacific Plate beneath the South China Block. The timing of the three episodes of magmatism coincides roughly with the published ages of mineralization in the Dabaoshan ore district, suggesting a genetic relationship. [ABSTRACT FROM AUTHOR]

Urban land structure, layout, and land-use mode influence regional sustainable development greatly. However, planners usually cannot work perfectly because of insufficient environmental information for decision making. In recent years, with urban geographic information system (GIS) development many cities have already built up integrated urban information platform to support regional digitalization process. By using spatial data mining technology urban planning related knowledge can be discovered form GIS database to help planners and decision makers in their work. Through analyzing of Chinese cities’ construction mode and developing trend, this paper illustrates how to build up an urban planning spatial decision support system (UPSDSS) based on exploratory spatial data analysis technology support. By spatial data mining form GIS database, UPSDSS can provide related knowledge for urban planning decision making with inference engines (rule inference and case inference) support. As an important part of the research, UPSDSS had been used in urban planning management of Harbin city in China. With hidden information discovered by UPSDSS Harbin planners work easily and effectively. Three cases demonstrate how UPSDSS helped Harbin city in policy making in macroscopic urban expending planning, underground exploitation scheme making, and local land structure changing. [ABSTRACT FROM AUTHOR]