Is It Hiking, or Is It Geology?

Spring. The time of year when a young man’s fancy turns to thoughts of—rocks, if he’s a geologist.

Actually, that isn’t quite true. Geologists think about rocks all year around. The difference is that spring is the time they can start to go out into the field again to examine the rocks that have been covered with snow all winter.

Living with a geologist, one would think, means lots of opportunities to go hiking. It does. That’s the good news. Those opportunities involve geologic hiking rather than ordinary hiking. That (to a non-geologist) is the bad news.

Because, you see, when geologists are out in the field they aren’t just walking around looking at rocks. They’re stopping to examine rocks. They’re pondering. Some of the time, they’re doing geologic mapping. This is to regular hiking what geologic time is to regular time. The pace might be described as glacially slow.

Here is what geologic mapping looks like to a liberal-arts-person observer who has come along on a student field expedition in the naïve belief that exercise will be involved:

You walk a little ways, and you stop and break rocks open with your rock hammer to look at them, and sometimes you check them with your magnet or your hand lens. You discuss them with your working partner (in the case of the students) or with a group of students (in the case of the instructors) or even sometimes (in case no one else is available) with your liberal-arts-person assistant who can’t tell the difference between marble and granite anyway but is too polite to say so. From time to time you take a GPS reading so you know your exact coordinates. You stop frequently to make notes in your field book or to mark things on your map with your colored pencils. Sometimes you sit down to do this—on a rock, naturally.

The map is taped onto a piece of cardboard so the wind won’t blow it away, and quite often the liberal-arts-person assistant gets to carry it.  Sometimes she even gets to carry the rock hammer—though she has an unfortunate tendency to hit herself in the knee with it if she isn’t careful. She has been told that a geology student isn’t allowed to graduate until he (or she, though this practice seems to be more prevalent among male students) has mastered the art of throwing his rock hammer into the air so it spins, then catching it by the handle as it comes down. She admires this skill. She isn’t ever going to try it.

After tagging along on enough expeditions such as these, I’ve learned the difference between geologists and the rest of us. Most of us tend to think of the earth as static. There’s a hill, here’s a stream, there’s a canyon, here’s a piece of prairie; and that’s just the way things are. Geologists, on the other hand, understand that the earth is constantly changing. They know that this high meadow once was the bed of an ancient stream, or those hills once were deep beneath the earth, or that this prairie was once the bottom of an ocean. They understand that the planet is still being shaped and reshaped, so gradually that most of us can't comprehend it. They have the ability to think in terms of millions and even billions of years.

That, to me, is even more impressive than the ability to catch a spinning rock hammer.