Fractures, Fluid Flow and Mineralization

Abstract

How is it that normal loads cause fractures to be closed within a few hundred meters of the Earth's surface, yet delicately banded hydrothermal veins up to meters thick are relatively common in the shallow crust? Why is there a correlation of fracture density and interconnectivity and ore bodies in mineral deposits? We have learned the inextricable interdependence of heat transfer, chemical transfer, and deformation in fluid flow from the daunting task of securing nuclear waste materials for millennia and trying to develop alternative energy resources such as hot dry rock regimes. With fracture‐controlled flow dominating in magmatic and hydrothermal environments, permeability is a critical parameter. Understanding the causes of it and how it interplays with heat and chemical transfer is fundamental to understanding the behavior of all types of fluid flow in the crust.