Can someone define stratified sampling for me?
“Stratified” usually means “layered”, so in the context of earth sciences & geology this would usually imply sampling of layered sediments or sedimentary rocks. As a geologist, you might, for example, sample the rock samples, rock types or fossils working up a geological sucesion, for example, a cliff face, as opposed to walking along the section in which case you would usually observe an entirely different variation. You might wish to examine soft sediments by taking shallow boreholes or auger (core) samples and focussing on the different layers (strata) as you work downwards into deeper and older sediment. Other things than rocks and sediments can be stratified; for example, water bodies (lakes, seas), which can be layered according to temperature, acidity, oxygen content, suspended sediment content and microfloral content. Other than that, this is difficult to answer because the question is pretty vague…
