00:00.00 archpodnet Welcome back to episode one zero three of the rock art podcast and this is Chris webster interviewing Dr Alan Garfinkel and we're talking about dating some of the oldest rock art in North America and a lot of stuff that goes along with that. This isn't a simple topic and when we left you were talking about this. 00:04.88 Alan Are. 00:16.77 archpodnet Massive effort that you're working on in organ after a huge fire and some of the obsidian hydration dating that they were doing on of course Obsidian projectile points. So what? what is obsidian hydration dating how does that work. 00:28.96 Alan Well, you know we've had our friend Saydy Rogers and he talked about what that was. He's one of the pioneers and one of the state of the art experts on this and he moved up to Washington Volcanic Lass has the ability to pick up water and diffuse it water molecules go into it when there's a fresh. 00:37.11 archpodnet Um. 00:48.54 Alan Break and it produces a rind a measurable rind in microns and that particular thickness of that rind and the chemistry the geochemistry of the Obsidian the volcanic class as to its source and geographical. You know. 00:53.62 archpodnet Ah. 01:06.69 Alan Proclivities and also the temperature regime within the site itself. The location can produce an equation that can give us a reasonable estimate with considerable accuracy on the age of that artifact and when that. Particular artifact was fashioned. You can do this on projectile points. You can also do this on on flakes and all kinds of volcanic glass What you want is you want ways to collect to cross correlated it so you want radiocarbon dates. Or you want ages of projectile points or you want other means of tagging or associating the rim readings to the actual true calendar dates and the more information you have on those particular relationships. The greater precision you can have on the age of the artifact. Plus if you get larger and larger numbers of these readings on more and more artifacts you can get a better and more precise age Determination. How's that. 02:18.22 archpodnet Yeah, that's pretty interesting I remember doing a big project across Nevada where we sent a lot of stuff in for obsidian hydration dating and of course you know we don't necessarily like to do that if we don't have to because it is a destructive dating method unlike some others because you usually have to cut a little notch in it to actually. 02:37.17 Alan That is that is correct. You do need to what away what I had what I had forgotten to do is. 02:37.43 archpodnet Ah, measure that rind right? And um, yeah, oh. 02:48.13 archpodnet Start start over with what I've forgotten to do. 02:50.84 Alan What I've forgotten to tell you is that basically to acquire that reading you need a thin section so you have to cut cut the artifact on its edge using a you know Geological saw. 03:02.30 archpodnet Ah. 03:09.50 Alan And then you grind down that that particular piece that chip off the side of the artifact until it's paper thin and then you can read it so it does it is destructive to to a point but but you can do this on flakes. You can do this on on Obsidian. Ah. 03:18.37 archpodnet Brett. 03:27.57 Alan Points do it on darts, etc, etc. And and I guess I was blessed because I was one of the pioneers in terms of developing not not the method but using the data to determine ages way back when I I began it using it on. Um. 03:28.17 archpodnet Um, yeah. 03:46.51 Alan On casa diablo obsidian from California and we use the the midpoints of temporally diagnostic of time sensitive projectile points and the information about those particular readings on those artifacts to establish an equation. An equation that would predict if you had a reading of a hydration rim what the age of that artifact would be I think you understand right? Yeah, so yeah, so that's what we had done and um, surprisingly enough my initial approximation was quite accurate and. 04:12.90 archpodnet Okay, yeah for sure. 04:25.39 Alan Quite close to the equations which are used to this very day and Sandy Rogers has been one of the pioneers on this and has published extensively trying to move the move the you know move move the move the edge learn more. And and grasp more and control more of the variability and the variables that might affect this kind of exercise and so we happen to have some of the smartest and best people in the world doing our obsidian hydration dating on this Oregon project. And we did hundreds and hundreds and hundreds I think it was four hundred or five hundred ah readings ah on the materials that we had and the reason I mentioned this in light of our discussion was we found readings that based on their equations. Date to eighteen thousand years ago for artifacts so now in the olded days. We would say oh that's an outlier. It's a wrong wrong date that's it that to da but given some of our our newer assignments. 05:22.49 archpodnet Wow wow. 05:37.94 Alan And the newest understandings of some of the antiquity of the aboriginal activities that appear to be associated with the in migration that peopleing of the Americas those are not unreasonable dates. Those could actually be valid. We could have it. We could have an 18000 year old artifact. We could have a ah 16 or 15000 year old artifact. They've got dates now that show that they are there is aboriginal activity human use of North America coming in minimally at 16000 and. 05:57.92 archpodnet Um. 06:14.41 Alan Probably older and yeah, yeah, and so there's ah, there's a sea change going on. It has to do with ah you know rethinking the whole possibilities of when and how and where. 06:15.52 archpodnet Wow, That's really cool. 06:34.39 Alan The initial migrations into America took place and how that transpired when you look at a map of where you find paleoindian remains there the float the fault. The clovis material is in south eastern United States around Texas it's it's a hotbed there and that may have been one of the migration migrational routes through that area and up into the area of the american southwest and onto the plains but the chances are they did that through. 06:54.32 archpodnet Um. 07:07.64 archpodnet Right? You know real quick back to Obsidian hydration dating I Wonder if there's been any talk about this because I have never thought to look it up but you mentioned I mean that area in organ that you guys were working that. 07:11.44 Alan Some sort of watercraft. They've also begun to go ahead. 07:27.40 archpodnet Was affected by fire. Obviously for that area over the course of the last eighteen thousand years that wasn't the only fire to go through there. In fact, there's probably been hundreds if not thousands of fires to go through there. That's just how nature works. Do we know if. 07:38.20 Alan Yes. 07:43.45 archpodnet The effects of forest fire that extreme heat that happens has any impact on the overall rind formation on the Obsidian for Obsidian hydration dating and I'm I'm wondering that because I know that rind is only microns thick and takes centuries and centuries to actually grow. Depending on the environment that the Obsidian is in Obviously it's a more moist environment. It's going to grow a lot quicker if it's a more dry environment. It's going to grow slower but you know does that relatively quick geologically speaking fire that goes through there have any impact on that I wonder you know because because we don't know how many fires happened in the past. 08:18.72 Alan So I get I I get I I can answer that question Very um, very confidently we um, ran we ran ah all the presentive points. 08:19.15 archpodnet That's almost impossible to tell. 08:26.11 archpodnet Okay. 08:33.11 Alan That were found on surface on the surface of the ground from that fire and all of them didn't have any Obsidian hydration rooms so they were all reduced or vanished from the fire. Yeah, now where we got all the readings. 08:44.30 archpodnet Wow Wow. Okay. 08:52.79 Alan From subsurface below ten centimeters or even a little bit deeper deeper than that down to the about a meter in depth and so most all of our readings I would say 98% of them are from subsurface context so that they would at least be insulated. 08:59.29 archpodnet Um. 09:11.72 Alan From some of the ah you know the recurrent fires. 09:14.16 archpodnet Well, which begs the question before it was actually buried through geological processes. You wonder if it was reset so to speak with a forest fire which would inherently make everything you're seeing possibly older Anyway, which is even more fascinating. But. 09:23.84 Alan Yes, yeah, yeah, yeah, no, but you're right? You're right? and so especially working in Oregon that's certainly something to consider and our friends mention that. 09:33.35 archpodnet Yeah. 09:39.65 archpodnet Um, yeah. 09:42.93 Alan In their research. Um, when we look at that kind of thing in the great basin. You don't have that that level of intensity or fires and so you would have much less of an impact on the on your calendar your clock your Upsidian clock. So. 10:01.20 archpodnet Um. 10:01.99 Alan That that would be less less invasive and less less of a yeah possibility. My ah colleague colleague who alerted me I published an article on the paleoindian remains that are right there on the eastern skirt of the Sierra Nevada as a 10:06.90 archpodnet Top. 10:19.96 Alan Site called the Borden site which had fluted points and basically thin points as well. They were all obsidian and some of the ah rhnds were enormously large for obsidian hydration dating and the dates would have gone back to 1415 even 10:34.20 archpodnet Um. 10:38.72 Alan 16 or 17000 and of course they were ruled ruled out as unreasonable but given some of our newer understanding of the potential age and in migrations and activities ancient cultural activities for the late pleistocene. 10:40.96 archpodnet Um, wow. 10:57.98 Alan Maybe they're not so wild. Maybe there is some limited activity that goes back to that age so it it opens up a whole different perspective. 11:06.48 archpodnet You know, speaking of perspective I'm wondering how we're ever going to answer this question who got here first right when when was the when was the actual first peopling of the Americas and what is the smoking gun because it seems like. 11:14.57 Alan Right. 11:22.93 archpodnet Ah, it seems like short of having some rock art that we can date to eighteen thousand years ago that shows people in boats you know, short of having something that says we were here and here's how we did it. We're basically looking for the oldest spot in North America and and obviously South America as well. 11:28.30 Alan Yeah, exactly yeah. 11:40.51 archpodnet What is the oldest thing because the older we get obviously people were there if we can prove people were there and then the older and older and older. You get you can keep going back and saying okay well this is older than over there. So they must have been here first you know, but that also that also assumes that people only got here one time. 11:53.97 Alan There it right? Well America is something that's a little different because when when it was additionally populated. It was very late in time. 11:58.77 archpodnet Which people probably got here lots of times from lots of different areas. 12:12.65 Alan Compared late late to the party as we called it because ah, there just wasn't people here very early compared to and all the other continents were far more ancient. Um, additionally if you looked at like if you study languages right. 12:13.51 archpodnet Yeah. 12:26.96 archpodnet Ah. 12:29.38 archpodnet Rent. 12:31.11 Alan And you look at the genetics genetics of it. There's there's a genetic clock and a linguistic clock and now we have an archeological clock and they all seem to be timed to about Twenty Thousand years ago would be about the about the most ancient that would seem to be reasonable for a um, initial populating. Of the americas both looking at the language and the genetics of it all. So now there is a taste of even more ancient material in South America and that has always been rather controversial. But. 12:51.21 archpodnet Ah. 13:09.86 Alan That's a whole other question. So anyways, right? So anyways if I jump back and start talking about this kind of rock art that we find that dates to what we're looking at is sort of the late pleistocene early. Holocene. 13:12.42 archpodnet Um, right. 13:29.18 Alan It's it's called great basin carved abstract. Great basin carved abstract so you you may have seen some of that Chris when you were looking at the the uppermost parts of little petchliff canyon. 13:34.78 archpodnet Okay. 13:43.31 archpodnet Um. 13:46.26 archpodnet Okay. 13:48.36 Alan And if you look at the walls of that canyon there's almost sculptural rock art. It's that they dug and excavated almost it went it went into a concavity and it would and it appears to almost be contoured around the rocks. So. It's ah it's a whole different kind of ah of a technology or strategy for producing these images that are exclusively abstract they're they're wavy lines. There's Chevrons. There's a sort of circuititous and serpentine kinds of figures. But there is no naturalistic or realistic subject matter during this earliest rock art period. But what there is is a very distinctive style of definitionally crafting. And expression of imagery and and I've thought about this a bit and I even listened to some of my earlier podcasts and I was shocked to hear a discussion of this that seemed to make some sense. There's something about. Grinding or polishing or smoothing or digging out of some sort of ah a deposit or a rock or ah or some or some creating some sort of ah of an artifact that has. 15:25.89 Alan Implications religious or theological implications communicating power power and might and activity and sacredness etc. And so this particular grinding and regrinding and. 15:32.83 archpodnet Um, ah. 15:44.71 Alan Effort that has been placed on this earliest rock guard must have had a function or a significance and ah and a meaning and there was an archaeologist who spoke about this and sort of talked about it almost akin to the grinding and polishing of some of the more. Beautiful objects that we ah see in the archeological record and he thought that that had to do with the intensity the the particular ah recreation or activity and the effort necessary to create those images. And imbue them with power does that make any sense. 16:26.55 archpodnet That does and that leads to a whole bunch more things I want to talk about and let's do that when we come back but in the meantime take a look down at the links in your show notes. We do have pictures of some of these things at some of those links so it will really help out I've got to. Article on the Winamucka Lake Petroglyphs and something on Paisley caves as well and of course Dr Garfinle's resources. So check those out. We'll be back in a minute.