HR: 11:10h
AN: U52A-05    [Abstracts]
TI: Spatial Variability of Multifractality of Exploratory Geochemical Maps
AU: * Cheng, Q
EM: qiuming@yorku.ca
AF: China University of Geosciences, 388 Lumu Road, Wuhan, HB 430074,
AU: * Cheng, Q
EM: qiuming@yorku.ca
AF: York University, 4700 Keele Street, Toronot, ON M3J1P3,
AU: Xie, S
AF: China University of Geosciences, 388 Lumu Road, Wuhan, HB 430074,
AU: Chen, Z
AF: China University of Geosciences, 388 Lumu Road, Wuhan, HB 430074,
AU: Xu, D
AF: China University of Geosciences, 388 Lumu Road, Wuhan, HB 430074,
AU: Xu, D
AF: York University, 4700 Keele Street, Toronot, ON M3J1P3,
AB: Exploratory geochemical maps created from concentration values of trace elements in the earth surface media (rocks, tills, soils, stream sediments and water) for mineral exploration and environment impact studies often show singularities that can be mathematically described by means of fractal and multifractal models. Implementation of multifractal modeling in various scales (entire map, sub-areas of maps and pixels) can characterize localized multifractality of geochemical maps which have been proved useful for description of underlying geo-processes responsible to the spatial variance of geochemical fields. This paper introduces several indexes of local singularity and multifractality that have been proposed for mapping spatial variability of geochemical fields and for delineating anomalous areas for prediction of undiscovered mineral deposits. Average singularity and variability of singularity over entire map, sub-area and pixels are calculated from exploratory data and compared for several mineral deposits types in various mineral districts. The results show that the estimated values of local singularity and its variability within a small area can be used to characterize geochemical fields related to mineralization. As a case study, maps at 2km spatial resolution created from concentration values of twelve trace elements Au, As, Sb, Sn, Zn, Pb, Cd, and Ag etc. in more than 25,000 stream sediment from Yuannan Province, China were used in this research. It shows that hydrothermal mineralization processes corresponding to gold, lead/zinc, copper, tin and nickel etc. in the Yunnan Province generally correspond to local singularity in geochemical data in stream sediments. Identification of mineralization caused local singularity using multifractal models can assist in mapping anomalies for prediction of mineral deposits.
DE: 4440 Fractals and multifractals
DE: 4450 Nonlinear maps
SC: Union [U]
MN: 2007 Fall Meeting