By Steve Black
The 2014 Eagle Nest Canyon Expedition concluded at the end of June. We returned to canyon for several short sessions in July and August to finish taking geoarch samples, document flood damage, backfill several units, and haul out some of the equipment stranded by the June 20 flood. Now that we are back from the field, our research continues apace. This post highlights the ongoing efforts of the ASWT project and its many collaborators, most of whom have been featured in (or contributed ) earlier blog posts.
Charles Koenig and I are back at Texas State in San Marcos where I am concentrating on teaching, writing, and riding herd on graduate students, while he continues to work fulltime on the project. Charles has spent weeks pulling our field data together—six months of fieldwork resulted in tens of thousands of digital files (mainly images), hundreds of field forms (mostly digital), handwritten field notes, sketch maps and hundreds of bagged samples—matrix, micromorph, artifacts, faunal and floral remains, and other samples. This data must be carefully accounted for, backed up, cleaned up, organized, and stored temporarily, essential steps in the research process.
Earlier blog posts have explained how SfM (Structure from Motion) photogrammetry is a crucial part of our field documentation. [For background see The Structure from Motion Revolution.] But while we had “stitched together” most of the SfM sets and “built” many of the 3D digital models in the evenings while we were in the field, much is left to do. Charles continues to finish up and improve SfM models we didn’t complete in the field and generate new models, integrating these in GIS (with remote help from former ASWT intern Bryan Heisinger). Charles is also summarizing critical data sets in spreadsheets and in graphical form so we can “see” what we have to work with, plot the analyses, and parcel out samples to our many collaborators. The accompanying 2D illustrations of the SfM long profile in Skiles Cave give you an inkling of how many matrix samples of different sorts we collected.
These orthophotos of Profile Section 3 show the TDS-plotted locations of some of the many samples collected at Skiles Shelter.
We knew from the get-go that we would be collecting many samples of artifacts, ecofacts, and matrix and assessing both their short- and long-term research potential. Analyses of high priority samples are already underway and we will soon be parceling out more samples to the specialists on our collaborative team. But first we have to go back to our research plan, as modified by field reality, and, in concert with the below-mentioned specialists, work out strategies and priorities for diverse, complementary analyses. The studies presently underway are quite diverse.
Drs. Leslie Bush and Kevin Hanselka are getting started on identifying plant remains from a few of the many samples we collected. First, they are concentrating on high-priority macrobotanical samples that TxState graduate student Dan Rodriguez collected in Kelley Cave and Skiles Shelter in 2013. Soon Charles and I will be going over our 2014 samples with the full macrobot team – Dr. Phil Dering, Leslie and Kevin – and work out our strategy. [For background see The Archaebotanical Team Forms.] The macrobotanical analysis will take years, if not decades, to fully complete. This fact highlights the nature of the excellent preservation conditions and the intensity of our sampling approach.
Bristlegrass seeds that Leslie Bush recently found in one of the Kelley Cave samples. Are these the result of human processing or by brought in by rodents?
Dr. Chris Jurgens is doing parallel analysis of the bones Dan collected from Kelley and Skiles. [For background see "Come Visit."] Chris and Dan have been working together several days a week for the last month or more. They first clean the bones, most of which are fragmentary, and then Chris examines these under a binocular microscope and calls out categorizations and identifications to Dan, who enters these data in a database. Dan also assigns specimen numbers to informative bones and repackages these. This week they finally finished all of Dan’s samples. Dan is working hard on his thesis, which he should complete this winter.
Another of my TxState graduate students, Matt Basham, is trying to finish his thesis on the cooking features he documented and sampled along the canyon edge overlooking ENC in 2013. Matt is seeing some interesting patterns consistent with (I think) the hypothesis that most of these burned rock features are the heating elements for earth ovens. These features are on or near the surface and buried very shallowly, hence organic preservation is limited to mainly charred plant remains, which Phil has now identified.
In August we sent a final batch of identified plant remains from Matt’s features and from Dan’s excavations to Dr. Raymond Mauldin at the Center for Archaeological Research at UTSA. Raymond is processing the charred bits to prepare the target samples used in radiocarbon dating, which he will send to an AMS lab he works with. Our fingers are crossed in hopes that this batch of dates will come back in time for Dan and Matt to add this to their existing 14C dates.
TxState graduate student Amanda Castaneda continues to make progress on her thesis research on the bedrock features of the Lower Pecos. Her work and that of Drs. Tammy Buonasera and Dani Nadel (and others) will be featured in a future blog post.
Blog followers know that geoarchaeological investigation under the leadership of Dr. Charles Frederick is a big component of our ENC research program. [For background see Geoarchs in Action.] Charles and his geoarchaeological colleague Ken Lawrence have come to the canyon numerous times to study the stratigraphy and take samples. And this fall they continue to mentor our former ASWT intern Jake Sullivan and TxState graduate student, Tina Nielsen.
Tina is developing a “microstratigraphic” approach to understanding how Eagle Cave deposits formed for her thesis and geoarchaeological analysis will be an important part of her research. So, she and sometimes Jake have been making weekend pilgrimages to Frederick’s lab near Dublin, Texas. Charles shows them how to use his specialized equipment and lets them loose on analytical tasks like preparing micromorphology samples for thin sectioning , determining sediment size distributions, and measuring magnetic susceptibility. [For background see "My Time in a Geoarch Lab."]
A pilot study of four matrix samples from Eagle Cave is taking place across the Atlantic at the University of Edinburgh in Scotland where paleoentomologist Dr. Eva Panagiotakopulu has been looking for insects. [For background see Archaeoentomology?] Several months ago Frederick, who talked his former colleague Eva in to taking part in the ENC research, sent her 3 liter matrix samples from several contrasting contexts in Eagle Cave. Recently Eva relayed the excellent news that she has hit “pay bug”, so to speak, and found extremely well preserved and abundant insect parts in several of the samples. This exciting news presents us with the new challenge of raising funds in support of Eva’s research – she will need to gain access to comparative collections from the region and start learning the identification and ecology of the beetles and other insects that are apparent in the pilot samples. This will be the first such study in the Lower Pecos.
Insect parts that Eva Panagiotakopulu has recently and tediously removed from an Eagle Cave matrix sample.
The massive flash flood in we experienced on June 20th is proving to be very instructive and more destructive than we had realized. [For background see The Canyon Runs Deep and The Canyon Transformed.] On the positive side, Mark Willis was able to fly along the canyon edge with his quadcopter drone nine days after the flood to document the transformation of the canyon. By comparing the SfM models created by earlier drone photography by Mark and Dr. Chet Walker with the after-the-flood model, we will be able to document and measure the havoc wrought by 11.6” of rain in eight hours.
Mark Willis operates a quadcopter drone along the canyon edge overlooking Eagle Nest Canyon a week and a half after the June 20th flood to document the changes to the canyon floor.
Mark’s quadcopter is equipped with a digital camera.
Belated news of the flood landed a new collaborator – Dr. George “Rudy” Herrmann, a retired hydrological engineer who grew up in Del Rio and went to school in Comstock. Rudy is now helping Charles F. put the 2014 Langtry flood in hydrological context. Preliminary water-shed and discharge analysis puts this flood at greater than a 1 in 500-year “return” interval. This means that, on average, floods like the one we witnessed last summer can be expected to reoccur over 500 years apart. Charles F. and Rudy are working now to relate the modern flood history with the ancient flood history documented in our excavations in Skiles Shelter.
Less happily, in late July we were finally able to make it up the canyon and revisit Bonfire Shelter, which we had thought was high and dry above the flood. Safely above the raging waters in the canyon below perhaps, but not dry. We saw clear evidence that run-off waters had poured into the main excavation block from all sides, causing considerable erosional damage to the exposed deposits. Charles K. and I began to document the damage with initial photographs and have put together a report that we are sending out to our archaeological colleagues who have a vested interest in the site. While the ASWT project has its plate more than full with our research elsewhere in the canyon, we could not ignore the Bonfire situation. In concert with the Skiles family we have called on our colleagues for help to conserve substantial portions of the site for future generations, while at the same time re-addressing decades-old research questions and perhaps tackling a few new ones as well.
When the run-off water reached the main trench in Bonfire, it began to erode the wall underneath the wood-plank path. Eventually this caused a substantial collapse (left), which also revealed several disintegrating bones. The fresh collapse exposed dozens of microstratific layers likely associated with Bone Bed 3 (right).
Finally, I am pleased to report that we will be presenting papers on our unfolding research at Eagle Nest Canyon at the Texas Archeological Society meeting on October 24th in San Marcos and at the Society for American Archaeology meeting in April, 2015 in San Francisco. Charles K. and I have organized a TAS symposium entitled simply “Eagle Nest Canyon. “ For SAA, I put together a symposium called “Low Impact, High Resolution: Ongoing Investigations in Eagle Nest Canyon.” All of the individuals named in this post are giving, co-authoring, or contributing data to papers at one or both symposia. I hope to see some of you there.
We may be back from the field for now, but our ENC research has just begun!
We also continue to analyze and report the results of the 2011-2012 ASWT research along Dead Man’s Creek (DMC), a tributary of the Devils River. TxState graduate student Ashleigh Knapp trying to wrap up her thesis study of the Little Sotol site, a plant baking facility (BRM). Josh Haefner, who holds his M.A. from TxState, has just volunteered to study the lithics from three BRMs we sampled in 2012. As the below photo shows, we recently returned some of the artifacts we documented at Little Sotol and from the DMC site survey reported in Koenig’s 2012 thesis.
Charles Koenig looks on as Rick and Mary Rylander take a first look at a display table with a small selection of the artifacts the ASWT project documented at the Ryes ‘N Sons Ranch along Dead Man’s Creek in 2011-2012. This handsome table was crafted by Dick Schlenk from standing deadwood cedars harvested on the ranch that are thought to date to the 1950s drought. Charles and Jack Johnson put together the display. Soon after this photo was taken we replaced the clear lexan table top that protects the artifacts.