AUTHORS: Kesler, S. E., Wilkinson, B. H.
ABSTRACT: We have shown that deposits that form deep in the crust have distinctly different age-frequency distributions from those that form at shallow depths and that this difference reflects the depths at which the deposits are formed. Confirmation that these age-frequency distributions are controlled by exhumation is seen in the fact that they can be used to calculate exhumation (erosion) rates that are identical to those estimated by other methods. A computational model constrained by the age-frequency distributions can be used to generate a deposit endowment for a steady-state Earth. Results of this model calculation provide information on the number and distribution of ore deposits throughout the crust thereby yielding the first quantitative estimate of the ore deposit endowment of Earth’s entire crust. Comparison of steady-state model results to those of the real Earth provide a quantitative method for identification of metallogenic provinces and epochs. Example model calculations show that currently known deposits make up less than 2% of Earth’s total copper endowment and confirm that Precambrian orogenic gold deposits constitute a highly anomalous metallogenic event.
KEYWORDS: metallogenic province, metallogenic epoch, age- requency distribution, ore deposit
SGA Members (50%) and Student Members (75%) benefits discount prices on all products. Log on the SGA website before adding items to your shopping cart.