Eagle Cave-Where Context is Crucial

By Brooke Bonorden, Bryan Heisinger, and Charles Koenig

Eagle Cave has been the scene of previous archaeological investigation (e.g., E.B. Sayles and J. Charles Kelley as well as the Witte Museum in the 1930s followed by the work by the University of Texas in the 1960s).  Looking at the surface of the shelter today, one of the first things people notice are the numerous unnatural depressions and mounds—vestiges of the decades of shelter excavation.  In fact, upon our initial arrival at Eagle Cave this past winter one of the first things that caught my (Brooke’s) eye in regards to the shelter’s topography was a large sloping depression in essentially the center of the rockshelter, running from the back wall to the drip line. It is massive! If I stand at the lowest point I can’t see over the present ground surface!  Now, several months later, it has become evident the modified landscape left behind by previous expeditions to Eagle Cave have created a challenge for our ongoing excavations in Eagle Cave: searching for intact deposits in their original context.

Profile Section 2 (PS02) is located near the rear wall of Eagle Cave.  The intact stratigraphy is visible as white bands in  both photographs.  Where Brooke is sitting in the top photograph, and Jake in the bottom photograph, is the disturbed fill we had to remove before we exposed the intact stratigraphy.  This fill is full of goat and sheep poop that has mixed in with the sediment when previous excavation trenches collapsed and filled in.

Profile Section 2 (PS02) is located near the rear wall of Eagle Cave. The intact stratigraphy is visible as white bands in both photographs. Where Brooke is sitting in the top photograph, and Jake in the bottom photograph, is the disturbed fill we had to remove before we exposed the intact stratigraphy. This fill is full of goat and sheep poop that has mixed in with the sediment when previous excavation trenches collapsed and filled in.

Let’s take a pair of scissors for example. When found in association with crayons, glue, and paper, a pair of scissors could be described as used for crafts. However, when the same pair of scissors is found in association with a comb, shampoo, and blow dryer, the scissors could be described as used for cutting/styling hair. Depending upon what an object is found in association with can completely change its interpreted use. The age of an artifact can also be determined by the other objects it is found in association with. In essence, context is crucial to understanding an artifact’s function within an archaeological site.

Depending on where an artifact is recovered from can drastically change the archaeological interpretation of that artifact.  Images from Google.

Depending on where an artifact is recovered from can drastically change the archaeological interpretation of that artifact–much like in Hollywood. Images from Google.

As archaeological methodologies have improved, the ways in which sites are recorded/mapped has drastically changed since the initial investigations at Eagle Cave in the 1930s. After reading the accounts of our predecessors’ work at the site, we knew the approximate locations where previous work had occurred, but we were unsure as to which areas of the site were still intact.  We set out to do so by exposing the vertical profile of a small area near the back wall of the shelter. In doing so, we soon discovered much of what we were excavating had previously been exhumed, and was in fact mainly backfilled sediment. We were able to identify the sediment as backfill because several feet of soil were completely homogenous in color and loaded with sheep and goat pellets.  We proceeded to clean more of the profile through the disturbed deposits until we exposed what we believed to be intact/unexcavated strata, and we are now excavating and sampling these intact layers systematically and recording the context where all the samples and artifacts are collected.

This is a composite image of eastern profile of PS02 showing the intact stratigraphy.

This is a composite image of eastern profile of PS02 showing the intact stratigraphy.

While we were excavating the disturbed fill from the profile we recovered dozens of artifacts—projectile points, flakes, fragments of bone, fiber—but none of these artifacts are in their original context.  Although some useful data can be collected from the artifacts themselves (e.g., projectile point styles), we cannot learn as much from many objects without knowing their exact archaeological context. This begs the question of how might we utilize artifacts and ecofacts (e.g., plant remains) with no known provenience?

This is a sample of artifacts recovered from disturbed context (from left to right): pebbles with paint, projectile points, bone tool, quid (chewed lechuguilla or sotol leaf), and a fragment of cordage.

This is a sample of artifacts recovered from disturbed context (from left to right): pebbles with paint, projectile points, bone tool, quid (chewed lechuguilla or sotol leaf), and a fragment of cordage.

ASWT has teamed up once again with Shumla, and we are taking some of the material recovered from disturbed contexts and creating an educational collection students can use for hands on activities.  Eventually, we hope we can bring these samples to classrooms not only in the Comstock/Del Rio area, but also to San Marcos and beyond.  The first group of students to study samples of the materials from disturbed contexts are part of the Shumla Scholars program.  The Shumla Scholars is a semester-long program for high school students at Comstock ISD.  Students explore research design by examining previous and ongoing projects, and by planning and implementing a project of their own. The main objective for the current class is to map and record the Comstock Cemetery, but another part will be to develop hypotheses relating to the artifacts recovered from Eagle Cave.  The students will be given several different artifact “packets” collected from disturbed contexts and posed the general questions: what are these artifacts and ecofacts and what can they tell us about the native peoples who occupied Eagle Cave?  Hands-on experiential learning instead of looking at pictures and drawings.

 

Students from Comstock High School screening disturbed fill at Eagle Cave.  These students will be the first to use the artifacts from Eagle Cave in hands-on experiential learning with SHUMLA.

Students from Comstock High School screening disturbed fill at Eagle Cave under the supervision of Vicky Munoz and Jeremy Freeman. These students will be the first to use the artifacts from Eagle Cave in hands-on experiential learning with SHUMLA.

We look forward to the Comstock students writing a follow-up blog post about what they learned from the Eagle Cave artifacts!

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Shumla Partnership

By Jeremy B. Freeman (Shumla Archaeological Research & Education Center)

As you have learned from this blog, the 2014 Eagle Nest Canyon Expedition is a highly collaborative effort among many specialists and organizations, such as the Shumla Archaeological Research and Education Center (Shumla).  Shumla is a non-profit research organization, based in Comstock, Texas, that has carried out archaeological research and public outreach programs in the Lower Pecos Region since 1998.  Shumla’s archaeology staff has documented and helped preserve the fabulous rock art of the Lower Pecos using new, innovative, and creative methods that have set the international standard for rock art research.

Charles Koenig, Steve Black, and Jeremy Freeman ponder what to do next in Skiles Shelter.  We are looking into the main trench through the site.  The white-brown contrast in the background marks the high water of the July 2010 flood when Hurricane Alex stalled over the region and dumped 10-15” of rain in just a few days. The inundation of this site, the lowest of the canyon’s rockshelters, highlights the ongoing threat and explains why we are digging extensively here.

Charles Koenig, Steve Black, and Jeremy Freeman ponder what to do next in Skiles Shelter. We are looking into the main trench through the site. The white-brown contrast in the background marks the high water of the July 2010 flood when Hurricane Alex stalled over the region and dumped 10-15” of rain in just a few days. The inundation of this site, the lowest of the canyon’s rockshelters, highlights the ongoing threat and explains why we are digging extensively here.

 

The Eagle Nest Canyon project is based at the Shumla Campus, and Shumla has loaned some of its equipment to the project, but perhaps Shumla’s greatest contribution is its personnel.  Vicky Muñoz and I (Jeremy) are staff archaeologists at Shumla, and we have been helping out with the Eagle Nest Canyon project whenever we can.  I did my undergraduate work at Heidelberg College and graduate work at Ball State University.  I bring over 14 years of field experience to the project including:  CRM projects, public outreach, academic research projects, and collegiate level-teaching experience.  I have specialized in historical archaeology, and I bring that background to look into aspects of cognitive archaeology (as related to the rock art), the creation of a common identity, and understanding how people perceived the sacred landscape.  Vicky is a recent Texas State graduate who attended Steve’s 2011 field school and has been involved with a number of ASWT projects.  Vicky is very versatile, and is a pro with Shumla’s digital technology—from TDS to database programming.

Vicky and I got our first taste of the Eagle Nest Canyon archaeology this past summer when Shumla and Texas State held a joint archaeological field school in Eagle Nest Canyon where students were afforded a unique opportunity to learn methods in dirt archaeology and rock art research.  On the rock art side, field school students helped document the pictographs in Kelley Cave, Eagle Cave, Skiles Shelter, and Raymond’s Shelter by photographing, illustrating, and collecting attribute data on the figures, and analyzing the stratigraphic relationships of the pigments using a Dino-Lite digital microscope.

 

Jeremy excavating a new layer of unit A-B at Skiles Shelter. The dust mask offers protection from the swirling clouds of fine powder spawned by troweling, screening, and merely walking through the shelter.

Jeremy excavating a new layer of unit A-B at Skiles Shelter. The dust mask offers protection from the swirling clouds of fine powder spawned by troweling, screening, and merely walking through the shelter.

 

Since January we have been working “in the trenches” alongside Texas State staff and volunteers.  There are times when Vicky and I work directly with one of the Texas State staff members (e.g. taking notes, screening, excavating, etc.) and other times when we’re sequestered to work on a unit independently so the Texas State staff can focus on other work; Steve and Charles know well that they can count on us to excavate and document the units properly.  We’ve helped with everything from running the total station, to excavating burned rock middens on the canyon’s edge, to helping dig units into the shelter floors and talus slopes.  And, last but not least, we have been assisting in taking the hundreds of sets of SfM photos to create 3D models of excavation units as well as that of Eagle Cave.  We are pleased to be able to contribute our experience and expertise to the success of the project.

 

Vicky Muñoz recording field notes on the north/south trench in Skiles Shelter.  Notes are both hand-written and digitized.  Vicky is almost directly under the shelter’s dripline.  As you can see, the talus slope forms a “vertical” burned rock midden.   Over several thousand years, hundreds of earth ovens were built near the front of the shelter and the spent rocks were tossed down slope.  And only a few meters away (behind Vicky),are vivid polychrome Pecos River style pictographs.

Vicky Muñoz recording field notes on the north/south trench in Skiles Shelter. Notes are both hand-written and digitized. Vicky is almost directly under the shelter’s dripline. As you can see, the talus slope forms a “vertical” burned rock midden. Over several thousand years, hundreds of earth ovens were built near the front of the shelter and the spent rocks were tossed down slope. And only a few meters away (behind Vicky),are vivid polychrome Pecos River style pictographs.

 

Excavating in the shelters of Eagle Nest Canyon has given me an opportunity to dust off my excavation tools and put them back in service.  In fact, this is really my first time to work on burned rock middens!  I had heard of them while working in the Midwest and Southeast, but had never had an opportunity to excavate one.  It just goes to show that even after 14 years there’s always more to learn.  The deposits in these shelters aren’t always clear cut, and subtle changes in the soil consistency may or may not indicate a significant layer.  And, the rocks can make it very challenging to keep the walls straight, requiring painstaking trowel work to even the walls around the rocks.  Digging through the dense deposits of burned rock often requires tools not typically in the archaeologist’s repertoire, such as garden claws and picks.  These are faster than trowels and work better than shovels, which tend to get hung up on the rocks.

Recently I spent a week excavating the tale end of Unit A-B at Skiles Shelter, which was opened as two side-by-side 1 x 1m units during the 2013 Field School.  At the end of the season the units were terminated at a deep, thick layer some 1.5m below the surface that had a dense concentration of small roof spalls and very little cultural material.  I’ve been using a pick and trowel to slowly work my way through the spall layer, which we hope may cover deeply buried intact cultural deposits, perhaps even Pleistocene-age deposits contemporaneous with Bonfire Shelter.  Thus far, deposits dating before 9,000 years have been elusive in the other shelters in the canyon.  Sadly, it looks as if the spall zone in the bottom of Skiles Shelter appears to be culturally sterile, although we haven’t quite reached solid bedrock yet.  The roof spall layer likely formed gradually over an extended period of time on the original floor of the shelter before humans began visiting this locale.

Brooke Bonorden using Shumla's TDS (Total Data Station) at Skiles Shelter, which means that the Texas State TDS could to be simultaneously at Eagle Cave, several hundred meters up the canyon.

Brooke Bonorden using Shumla’s TDS (Total Data Station) at Skiles Shelter, which means that the Texas State TDS could to be simultaneously at Eagle Cave, several hundred meters up the canyon.

 

Back to Shumla.  Shumla’s collaboration with Texas State’s ASWT team offers a unique opportunity to integrate data from subsurface deposits (i.e. “dirt archaeology”) with rock art research.  Traditionally there has been relatively little collaboration between dirt and rock art archaeological researchers, each using their own seemingly different methodologies to study “exclusive” aspects of the archaeological record. Only rarely have the data from each been combined for a more holistic interpretation.

By studying both the “dirt” and “rock art” archaeology of Eagle Nest Canyon, we are taking a holistic approach to studying the archaeology of the Lower Pecos.  This is made possible by the multi-disciplinary collaboration of different fields of study, including rock art research, archaeobotany, geomorphology, palynology, zooarchaeology, archaeoentomology, and dirt archaeology.  Shumla shares in the belief that by taking a broad approach to studying the archaeology, we can learn more about the prehistoric people of the Lower Pecos through integrating diverse intellectual perspectives, methodologies, and complimentary lines of evidence to help us to better understand how people utilized the landscape throughout the region.

Vicky and I are grateful for the opportunity to help with the ASWT project and are happy to offer our experience.  We hope that our collaboration with Texas State will help both organizations meet our objectives and collectively bring greater insight into the prehistoric lifeways and landscape use of the region.

 

Shumla returns to Eagle Nest Canyon amid the pale green colors of new spring growth.

Shumla returns to Eagle Nest Canyon amid the pale green colors of new spring growth.