Howdy Cacher - welcome to the Grayburg. Walk up to the hilltop, have a seat on the bench, and let's talk some geology. So we, the Grayburg - if you look down at this rectangle of rocks surrounding you - well, that's us - sandstone! We're the Grayburg sandstone. The next interesting tidbit is that we're really old. How old you say? Oh, about 267 million years - called the Permian. Your fellow humans put us here a tiny, itsy bity period of time ago, 1930s, as part of a 9-hole golf course for the doctors and workers at the Fort Stanton Tubercular Sanatorium. Ah, that's where you walked over here from - old Fort Stanton. It's made out of us too. Pretty cool, huh? In fact, this whole hill is us and that really cool trail and steps up here to the top in both directions, that's us too. Further - more cool stuff - if you look over your left shoulder, that whole ridge is us. And that long ridge to the north, across the Bonito Valley, it's Buena Vista Ridge on the 1908 map but now BLM calls it West Mesa (it's us too). Everything you see west and north is us, except that really pointy peak way west, which we'll get to shortly.
So check this out - if you turn around and look at that long ridge way over there to the south, that's not us - we know you've already been there - all kinds of P&Gs over there - easy pickins. So you may have noticed how it's all a light to medium grey color over there, and not brown and orange like us - it's limestone - our brother, the San Andres! Same age as us - and we're in contact all along that ridge and miles in either direction. A contact zone, as it were.
500 feet down over in that far ridge is the Snowy River Passage of Fort Stanton Cave, which is only a mere 10 million years old, although there's a cave mineralogist, who's dating the formations in there (no, not dating the formations, but, you know dating the formations - finding their age). And maybe that place is older than we thought. But not too much older - not like us and our brother, although the passage is inside our brother - we're not sure he likes that, especially when your fellow humans are climbing around in there - he says it tickles like crazy.
Anyhow, there's some other rocks up here that we ought to tell you about. They're mostly not related to us. So the steps you walked up to here on the north side of this hill, you'll notice big round cobbles lining the trail on either side of we larger, squared Grayburg steps. Well, if you look way off to the west - there's that sharply-pointed peak. That's Nogal Peak. So in the late Cretaceous Period, only a mere 65-million years ago, it was part of a volcano that blew up, we mean - Mount Saint Helens was nothing compared to when this one went up. And then over the millennia all these cobbles and little boulders got washed down, filling the valleys and valley slopes, so they get called valley fill. Not too glorious a name - but they don't mind it. And they're good pals - they're always hanging out with us (guess what kind of music we like? - it's literal with us. Well, we guess you too), and they-re also over around and on brother Andres. Kinda heavy though - not too easy for the humans to shape them like they did us
Speaking of which, that's where we came from. Well, actually, we came from that ridge over our left shoulder, but your ancestral pals did this thing called quarrying and moved us all from the ridge to the Fort, and then we got shaped and made into these things called barracks, with humans tickling our insides too. That was 1855. And then just a drop in the bucket short time later, 1930s, these people called the Civilian Conservation Corps, tore two of the barracks down to make way for the Nurses' Quarters. And then they re-purposed us to line the streets, shape up and stabilize the tubercular cottage terraces, create the Catholic chapel, and then bring a bunch of us out here to make up the tee boxes and the steps up to here. Nice view, huh? You would not believe how this view has changed since we started out. But that's another Earth Cache for later.
So, let's see what you've learned. You know the deal - don't post your answers here. You gotta email your answers to the brilliant, handsome, exceptionally outstanding, caver-type cache owner who put this Earth Cache together. Try for two answers but if you get them all, that's cool:
1. How old, geologically, is Fort Stanton?
2. How old is our brother, the saint?
3. Using your geosense, which direction from here is Fort Stanton Cave? (C'mon - you've been over there - you know, Lincoln County Challenge - the easy peasy stuff)
4. What geologic period did our valley fill buddies get blown sky high?
This Earthcache was established with permission from Tim Roberts, Manager, Fort Stanton and Lincoln Historic sites, Historic Sites Division, Department of Cultural Affairs, State of New Mexico. Phone: (575) 653-4025 or (575) 653-4372.