Everyone likes to classify things: by shape, by color, by cost, by size. You name something to sort by, and someone is busy classifying with it. So, it should be no surprise that geologists get classified. And perhaps the first way they get labeled is as either a soft rock geologist or a hard rock geologist. No, it has nothing to do with the character of their head (although some might disagree) and it has nothing to do with their taste in music. Rather it relates to the type of rocks they study.
Soft rock geologists study sedimentary rocks. Some aren’t particularly soft when they have been cemented and lithified (anyone trying to collect fluorite in the dolostones at Walworth knows this), but they were all pretty much deposited first as a soft sediment. Geologists who study the deposition and/or erosion of lake (lacustrine) or stream (fluvial) deposits, and those studying coral reefs, are soft rock geologists. They might focus on aspects of hydrology (most underground aquifers are hosted by sedimentary rocks). Paleontologists who study fossils and prehistoric life are soft rock geologists. So are those exploring for hydrocarbons.
On the other hand, another set of geologists spend their waking hours studying the so called “hard rocks”. These are rocks born of fire (igneous) or those generated from other rocks when deeply buried in the earth’s crust (metamorphic rocks). These folks are more likely to study plate tectonics or volcanology, or be involved for the search for natural resources resulting from magmatic activity or the hydrothermal processes associated with just about all subsurface processes.
In the beginning (i.e. college) I was a hard rock geologist. The copper deposits I studied in Arizona were generated around a granitic intrusive. I spent time looking for gold (notice the verb is not finding) in the volcanic terrain of Nevada. But sanity set in (i.e. the desire for a stable paycheck) and I flipped to the soft rock side and career in the oil industry. I will take credit for finding some of that! Anyway, oil and gas are born in sedimentary basins from decaying organic material almost all of which resides in the pore spaces of sedimentary rocks. Geologists in that industry are generally of the soft rock variety.
It seems the same dichotomy exists in the rock hound world. There are fossil collectors and there are mineral collectors and then there are some of us who enjoy both. Perhaps the dual nature of my career is why I now find hunting for fossils in the Devonian shales of western New York just as entertaining and satisfying as digging terminated minerals out of a pegmatite. You could say that this makes me bi-stonal (that’s a made up word, say it out loud). Or perhaps the best way to express it is that I am HR-SR (hard rock-soft rock), equally excited, motivated, and otherwise energized by geologic activity in either domain. The resultant corollary would be that I am not very selective about what I pile into my car and accumulate in the basement and backyard. In that regard, I know I am not alone.
So where do you fit in the rock hound classification scheme? Are you a soft rock, fossil collecting maniac? Or are you a hard rock, crystal seeking lunatic? There is no correct answer and you can be both.