Terry S. Maley

Not quite sure where author Terry Maley thought he was going with Exploring Idaho Geology. I bought it sight unseen, hoping for a field guide; instead it starts out as a very basic geology text – explaining sedimentary versus igneous versus metamorphic rocks, the geological time scale, folding and faulting, etc.; then suddenly it shifts gear to discussion of decollement surfaces, strontium isotope rations, and accreted terrain. All of this is illustrated with examples from Idaho, but this is not a field guide or road log; just general comments such as “the Purcell Sills are intruded into the Belt Supergroup in Northern Idaho” without any instruction other than very general map as to where you can actually see the Belt Supergroup or the Purcell Sills intruded into it. There are frequent illustrations – and they’re pretty good – but they are all line drawings and now and then a photograph. I stress line drawings here – on a drafting table with a T-square, lettering set, and piston india ink pens – no CAD here (well, not surprising given the 1987 publishing date, I suppose). I suppose Exploring Idaho Geology might be good for background before heading out in the field with road logs and a stack of geological maps, and it’s a decent introduction to some geological concepts, but it is useful for armchair explorers only.… (mer)