Abstract
Quantitative description and prediction of vein hosted deposits using fractal statistics have been tested using data collected from the Curraghinalt gold deposit, Sperrin Mountains, County Tyrone, N. Ireland. Goldbearing quartz veins are hosted by Neo-Proterozoic Dalradian (Southern Highland Group) age psammites, pelitic schists and graphitic schists. Veins trend E to ESE and cross-cut regional structures. Vein thickness (z) distributions closely approximate a power-law distribution of the form N(⩾ z) = cz -D,with an exponent (D) of 0.76 over three orders of magnitude. Vein spacing data approximate a log normal distribution with a mean of 2.92m. Numerical analysis indicates that the veins are more clustered than expected from a random distribution. Regions of high percentage extension and high vein density define vein clusters. The vein clustering relationship may be combined with the power-law thickness distribution and used in a predictive manner. The data may be used to constrain the probability of intersecting veins of potentially mineable dimension.
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Regrettably, Dave Johnston lost his life on 2nd October 1995 whilst carrying out fieldwork in western Ireland
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McCaffrey, K.J.W., Johnston, J.D. Fractal analysis of a mineralised vein deposit: Curraghinalt gold deposit, County Tyrone. Mineral. Deposita 31, 52–58 (1996). https://doi.org/10.1007/BF00225395
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DOI: https://doi.org/10.1007/BF00225395