Hydrogeology 101: Introduction to Porosity of Aquifers

This video introduces the concept of porosity in aquifers, and how it is affected by the compaction and sorting of sediments. It explains why a sandy gravel has a much lower porosity than a gravel or a sand, and also how cementation of the matrix reduces porosity. The techniques of porosity estimation are applied to estimate groundwater resources and groundwater recharge in a cemented gravel aquifer. 00:00 Introduction 00:25 Primary porosity 00:36 Secondary porosity 00:49 Porosity calculations 01:44 Range of porosity values 02:13 Alluvial gravels 02:52 Effect of packing 03:15 Effect of grain size 05:29 Porosity of a sandy gravel 06:49 Real world example 08:31 Effect of cementation 09:08 Groundwater recharge & MAR in a cemented gravel #porosity #aquifer #hydrogeology