Introduction

This chapter considers numerical estimates of effects for five individual factors that include density, mechanical strength, permeability, solubility in water, and thermal conductivity. The lower differential density near the top of the salt implies that the neutral lies within the salt column. The strength of salt on a geological time-scale is virtually nonexistent so that salt flows as would a fluid under impressed forces. The permeability of salt is generally estimated to be sufficiently low that, relative to sediments, salt is effectively impermeable to fluids. The maximum solubility of salt in water is about 250-300 ppt, so that seawater is highly undersaturated in salt. The focusing of heat by salt masses as a consequence of the higher thermal conductivity is a well-recorded phenomenon. Sediments in the vicinity of the top of a salt diapir are warmer than regional sediments. The chapter also presents an overview of the key concepts discussed in this book.