As far as the list of "questions most often asked of archaeologists” is concerned, the question of "How do you decide where to dig?” is right up there with "Have you ever dug up any dinosaur bones?” and "Have you ever found any gold?” Answers to the latter two are easy: No, and no. Dinosaurs, of course, were extinct many millions of years before anything recognizable as an ancestor to humans was around. And, only a very tiny minority (maybe 1000th of 1%) of all archaeologists have ever come even close to finding anything gold or related to the gold mining industry.
The first question, though, is a bit trickier to answer. And that’s because the answer depends on what it is you’re trying to learn from the hole you dig.
In an earlier journal posting, for instance, I explained in detail how we used the soil probe to look for evidence of prehistoric human activity. That is, we wanted to find anything that could be linked to people: charcoal, burned bone, stone tool fragments. In that case, we placed our "holes” (tiny though they might be) in or adjacent to landforms that on the surface resembled what we know in many cases to be house pits.
But what if we already know from previous survey work that people were living at a particular spot in the past, and our next goal is to obtain a representative sample of stuff that they left behind? We might be interested to know (and in fact we are interested in knowing) where the people living here obtained the raw materials to make their stone tools. We suspect that some of it was obtained locally from geological outcrops either on the island or from neighboring islands. But we also know that certain raw materials, like obsidian (volcanic glass, which can be used to make extremely sharp, but very brittle tools) were obtained (directly? through trade?) from Kamchatka, Russia and from Hokkaido, Japan.
So in order to figure out what patterns people were following in the past, we might want to place an excavation unit in an area that was likely to have been used as a disposal area for the debris from stone tool production.
As another example, my main interest (for lots of different reasons—see the "Makanrushi” journal entry for some details) lies in analyzing the faunal remains, or bone debris, left behind from the meals these people ate. As with the lithics, or stone tool analyses, we hope to find a representative sample.
For our team working this week on Rasshua Island, we are actually hoping to obtain a representative sample of both lithics and fauna. Fortunately for us, midden deposits typically have all sorts of stuff in them, including lithics, fauna, charcoal, broken stone tools, broken bone tools, pieces of broken pottery, and on and on and on. In modern times, most of us don’t have direct experience with what a midden might be. But one of my graduate advisors, Dr. Julie Stein, often describes middens like this: they are like that pile of stuff that many of us has in the corner of our garage: a mix of fully functioning tools, some stuff that is broken but could be fixed with a little bit of effort, and some stuff that should really just be thrown away.
Our archaeology survey team visited this site last year and already determined that there are several well-preserved house pits here. And we are hoping that this site will fill in some important gaps in our sampling of different time periods on different islands in the archipelago. So our first goal now that we’re here is to try to find a midden deposit that will yield (hopefully) all the things we want to sample.
Any guesses how we’ll go about doing that?
Yep, you got it: pull out the soil probes and start looking for patches of stinging nettles!
It’s pretty easy work, really. Today we did systematic transects across the site, with 4 people walking in a line, spaced about 5-8 m apart from each other. Every few meters or so, we’d each examine the vegetation, and then pull a sediment sample with the soil probe (see photo). In this particular case we skipped over any house pits, since we aren’t interested (and our permit won’t allow us) in excavating any of them.
Dr. Etnier examines the soil probe that has hit two layers of charcoal (identified by the black in the center and on the right-hand side of the sediment plug). This particular probe sample also has some small pieces of bone in it (the white spots).
We also had an extra person (me) trying to find any fox dens and rodent burrows that might have materials brought up from buried contexts.
So using this approach, we have located a spot 2 m X 4 m that we’re pretty sure is going to have a little bit of everything in it. We found some well-preserved bone, charcoal, lithics and pottery on the surface. And our soil probes found a layer of urchin shell below a nice, clear tephra layer. So we’ve got bone. We’ve got lithics. We’ve got pottery. And perhaps most important of all, we’ve got a tephra layer which we’ll be able to use as "time marker.” If we can be sure that the rodents and foxes have totally churned things up, anything stratigraphically above the tephra has to have been deposited after the tephra landed on the landscape, and anything stratigraphically below the tephra has to have been deposited before the tephra landed on the landscape.
So starting tomorrow, we’ll start working full-time on the excavation. Hopefully the rain we had off and on today (yes, we worked in the rain) will let up a bit. The good news about the rain is that it didn’t start until *after *we had gotten our camp fully set up, and after a beautiful sunset. We’ll see what tomorrow brings (we no longer have the benefit of nightly weather maps from the ship’s bridge).
I’ll keep you posted on how the excavation goes!
--Dr. E