teachable moments vs being polite

I've spent part of the past week in the field with my thesis student, backpacking into the fringe of a nearby wilderness area and then scrambling up avalanche chutes to look for cool metamorphic minerals in Precambrian metasediments. It's hard to explain what we're doing in a sentence or two - when we meet backpackers or fishermen, we usually just say we're geologists, and they ask if we've found gold, and when they say no, they assume we failed. (But we found sillimanite, and andalusite, and garnet, and some really funky reaction textures, so we're happy metamorphic petrologists. When I download my photos, maybe I'll post some.)

We've cut a couple miles off our backpack (and found a good river crossing) by making friends with the property owner on the wilderness boundary. When we go through the gate, we try to keep the donkey from escaping, and when we drive past the house, we stop and say hi, and usually hear some entertaining stories in return.

This time, we went through the usual questions. Did we find gold? No, sorry, but we'll keep looking. (It's not that big of a stretch; there are gold mines in the county, and there is apparently some mineralization associated with the pluton whose aureole we're studying.) But this time they asked some more questions, and my student did a nice job of trying to explain metamorphism in a few sentences.

And then the property owner decided to make this a teachable moment for her guests, and started talking about how all this had been under the ocean, and then the dinosaurs came, and then God made the mountains so the dinosaurs would have something big to walk around on.

My student and I just kind of stammered and said, yeah, this was all a long time ago, and headed out. (In our defense, it was late, and we hadn't eaten supper, and I have a four-year-old whom I wanted to see before bedtime.) But I wonder: should we have said more? We're working in Precambrian metasediments, probably about 1.7 billion years old, a kilometer-thick pile of metaconglomerate that grades upward into lovely cross-bedded quartzite and finally into a little bit of pelite. The underlying rocks tell the story of the building of North America by accretion of island arcs; the conglomerates could have been deposited in some kind of syn-tectonic basin or another, maybe during collision of an arc, maybe during some kind of post-collision rifting, maybe in some kind of small basin along a releasing bend on a strike-slip fault - we don't know how they formed, but they are thick and spatially restricted, and that says "yo! mountains nearby!" to me. And then they've been metamorphosed in the aureole of an anorogenic (?) granite. And then, after another 900 million years or so, they ended up under the Paleozoic passive margin sediments of North America, and then the dinosaurs showed up (after another 300+ million years or so), and then the dinosaurs went extinct and the mountains formed (probably in that order). And, you know, the story is really cool, and the mountains are beautiful, and I'm a big fan of knowing the country where one lives, whether one is a geologist or not.

But we were essentially guests, of someone who was interested in finding ways for us to make use of her property, and we wanted to maintain good relations. And, well, where do you start? (And she could have been pulling our legs, or exaggerating. And for the deeply religious, God pretty much does everything, and simply mentioning God doesn't necessarily mean she's a young-Earth creationist.)

So. Aside from inviting the property owners to my student's thesis presentation (which we will definitely do), and sending them a copy of my student's thesis (microprobe data and all, heh)... where on earth should we start? Or should we start? Would it be rude?