Application of Advanced Technologies in Excavation, Analysis, Consultation, and Reburial: The Alameda-Stone Cemetery in Tucson, Arizona

This post is part of Tech Week, which highlights a group of posts about specific applications of technology to archaeological investigations. This week, the focus is on Technology and Mortuary Archaeology. See the other posts in this series here.

In recent years, the technologies that have affected most how archaeologists do their work are digital and computing technologies. These technologies can greatly improve the accuracy, precision, and efficiency of archaeology as well as enhance our ability to analyze, share, and curate the data we generate. Of these tools, some of the most useful have been relational databases, geographic information systems, visualization tools, and digital mapping instruments, such as global positioning systems, total stations, and lidar.

A few years ago, I had the opportunity to participate in a large, highly complex, and community-sensitive excavation project in downtown Tucson, Arizona. The project was very important to Pima County—the project sponsor—the city of Tucson, and to multiple descendant communities. The project site was the location of the long-abandoned Alameda-Stone cemetery, a cemetery used by residents of the Village of Tucson beginning in the late 1850s or early 1860s. Divided into several sections, the civilian sections were closed to further burial in 1875, while the military section was closed in 1881. The 1,800 to 2,100 people buried in the cemetery were of diverse cultural and religious backgrounds, including individuals of Hispanic Catholic, Euroamerican Protestant, Jewish, Tohono O’odham, Yaqui, and Apache backgrounds, as well as military personnel.

After the cemetery was closed, a few hundred burials were moved to new cemeteries, but most were left in the ground. As Tucson urbanized and grew, buildings, streets, and utilities were built throughout the cemetery and all visible reminders of the cemetery were erased. Despite these disturbances, many of the burials remained intact when the cemetery was professionally excavated by Statistical Research, Inc. in 2006-2008.

To comply with legal requirements, including burial agreements for the cemetery excavation, all human remains and burial-associated objects within the 4.3 acre project area had to be recovered. The discovery of burials had to be reported daily and the location and status of all recovered items and materials had to be tracked throughout the duration of the project. Due to the large number of descendant groups who could claim remains from the cemetery, the cultural affinity of human remains and burial associated objects had to be established as firmly as possible using multiple lines of archival, contextual, and osteological evidence. Moreover, the project needed to be completed from beginning to end within a period of just four years. Most projects of this size are performed over a substantially longer time frame.

Figure 1. Use of a TEREX Powerscreen Mark II to recover artifacts and osteological materials from the project area overburden (image courtesy of SRI Press and Left Coast Press).

A variety of new technologies were used to accomplish these goals. Since all human remains had to be recovered, screening of the massive volume of cultural deposits, including overburden,  was necessary (Figure 1). Burial features were excavated by hand, but fragmentary remains were also present in secondary contexts in areas of the cemetery where burials had been disturbed. The recovery of these materials was accomplished using construction equipment and an automated screening machine. These tools required an operator to run and maintain, but their use greatly sped up the search effort and enabled all cultural deposits to be thoroughly screened.

To glean as much information as possible from exposed burials, burials were intensively documented in situ using photogrammetry and three-dimensional laser scanning, in addition to more traditional mapping techniques (Figure 2). Maps of burial features were then created in a geospatial laboratory using point-provenienced spatial data, orthorectified digital photos, 3-D scanning data, and analysis data. Recovered artifacts were stored and analyzed onsite and bagged using printed, bar-coded labels that allowed all recovered materials to be accurately provenienced and tracked throughout the project.

Figure 2. Illustration of the mapping process for Grave 13614, Burial 21829, an adult Euroamerican male (courtesy of SRI Press and Left Coast Press)

Excavation resulted in the intensive investigation of more than 1000 burial features and the recovery of the remains of more than 1300 individuals, making this one of the largest excavations of a historical-period cemetery conducted in the United States. Excavation also documented several prehistoric features predating the cemetery and more than 700 post-cemetery features, including building foundations, privy pits, utility trenches, and landscaping features. Use of the above technologies decreased field time considerably, making better use of field labor and allowing greater attention to be focused on analysis, reporting, and consultation efforts.

All the resulting data collected in the field and laboratory were stored in a sophisticated relational database system. The system allowed analysts to query and manipulate massive volumes of data in a flexible and consistent manner in support of diverse analyses and to differentiate remains according to cultural affinity, as required by the project burial agreement. In addition, the system provided a platform for tracking all the project materials from the moment they were discovered in the field until they were reburied or repatriated. As the project came to a close, the remains of more than 1300 individuals were repatriated or reburied. Advanced technologies continued to play a role in facilitating this stage of the project by ensuring that remains were repatriated and reburied correctly according to the wishes of descendant groups.

Of course, use of advanced technologies is not an alternative to solid, traditional research or careful project management. Much consideration and effort is needed to ensure that technologies are used appropriately and effectively. Many of the technologies implemented during the project require monetary investment to purchase or lease and, to implement them successfully, training or hiring of staff with specialized skills. Substantial computing resources are needed—including servers, networks, and software—and these have to be built, operated, and managed by skilled professionals. Archaeologists and other staff working on the project had to learn collectively how to make these technologies work together to answer research questions and fulfill project requirements. The project database and geographic information system had to be coordinated and continuously tested to make sure these systems were operating properly and analysts were working with the correct and most up-to-date data.

It was also important to ensure that the use of a technology did not take on a life of its own. Technologies are only useful insofar as they fulfill a need. Project leaders had to continually question how and whether a technology was successful in meeting a need of the project and to consider what could be done to improve performance. For a project of this size, which had as many as 70 people in the field at any one time and employed upwards of 150 people of diverse backgrounds and positions, project leaders had to manage positions as much as they managed people. People came and went over the course of the project, but the position they occupied always needed to be filled. Similarly, many computers, servers, and instruments were used over the course of the project. Some components failed or needed periodic maintenance, but the technology always had to be managed, monitored, and properly maintained.

Finally, many of the technologies used in archaeology today were not designed specifically to address archaeological problems. Substantial effort and planning can be needed to adapt technologies to archaeological needs and to develop systems and protocols for their use in an archaeological context. The unique requirements of the excavation project provided the rationale and funding for a large investment in advanced technologies, particularly those involved in mapping and database systems. Other projects could likely benefit from similar technologies but may not have the staffing or funding to invest in or manage them. What can the discipline do to foster the wider application of technology to archaeological problems and to promote broader access? Further, what are the most effective ways for archaeologists to share information on where technologies succeed, where they fail, and how they can be improved?

Read the final Tech Week piece “Mortuary Analytics on US Army Garrison, Fort Drum, NY” by Michael Sprowles

Further Reading:

Heilen, Michael P. (editor)
2012 Uncovering Identity in Mortuary Analysis: Community-Sensitive Methods for Identifying Group Affiliation in Historical-Period Cemeteries. SRI Press, Tucson, Arizona and Left Coast Press, Walnut Creek, California.

Mortuary Analytics on US Army Garrison, Fort Drum, NY

This post is part of Tech Week, which highlights a group of posts about specific applications of technology to archaeological investigations. This week, the focus is on Technology and Mortuary Archaeology. See the other posts in this series here.

Hundreds, if not thousands, of cemeteries can be found on numerous military bases across the county. Many date back to early towns and villages and hold the graves of early settlers and later, military personnel. The 13 historic cemeteries (2,100 markers) of US Army Garrison Fort Drum, New York are no different. (Fort Drum is located just east of Lake Ontario, and is the 107,000+ acre home of the US Army’s most deployed Division, the 10th Mountain Light Infantry.) Through the Directorate of Public Works (DPW), the Army works to maintain these cemeteries and to minimize military impact to these sites. Although on Fort Drum these responsibilities are carried out by the Cultural Resources Program (CRP) of DPW – Environmental Division, the process of stewardship can and does differ widely from one post to another.

Figure 1: Sheepfold cemetery, looking southwest.

Most recently, Fort Drum has acquired an intern (the author), through Oak Ridge Institute for Science and Education (ORISE), to inventory and “digitize” these historic cemeteries, while applying non-invasive geophysical investigative techniques. The premise for project was conceived by E.W. Duane Quates PhD, as a means for identifying sets of attributes associated with known African-American burials, which could also be applied to suspected unmarked burials, as a means of identification.

The primary goal of this endeavor was to create a geo-referenced database. Aside from a means of ethnic identification, this database would allow for more effective resource management, and grant the public ease of access to cemetery information. This information is currently available on The Fort Drum website as searchable SharePoint listings, and being developed into a fully interactive platform by Colorado State University’s Center for Environmental Management on Military Lands (CEMML).  A result of this dual-purposed database was also a large, easily manipulated, data pool which can be made available to outside researchers. The secondary goal of this endeavor was to use geophysics to investigate the possibility of unmarked burials inside of the cemeteries and outside of their boundaries. To illustrate the results of this project, results from Fort Drum’s Sheepfold Cemetery can be seen below.

Sheepfold cemetery (Figure 1) was part of the 200 acres owned by French aristocrat, James LeRay in the early 19th century. Originally this area is where he kept his sheep, his sheepfold. The cemetery contains 292 known burials (391 markers); the earliest known burial was in 1821, and the most recent burial was in 1996. As part of the (ORISE) project, the markers in Sheepfold cemetery were geo-referenced and recorded into a database. Ground penetrating radar (GPR) was also used to explore a large unmarked section of the cemetery which had been flanked by marked interments, including a known slave-turned-servant (Rachel) of the LeRay family. The results of this survey was compared against a control survey from a nearby area, which contained some of the oldest and most contemporary markers to those surrounding the open and unmarked survey area. As Figure 2 illustrates, the large, open, and unmarked area contains several anomalies which resemble the control of the smaller area in length, width, and depth, and are similarly oriented to the known interments of the cemetery (southwest to northeast).

Figure 2: Sheepfold Cemetery GPR survey results. Note: 6.56 feet below the surface, 3.28 feet thick slices.
(Image courtesy of the author)

The database offers tremendous opportunities for analysis, but required preparation. To maximize database versatility, many different attributes were selected, defined, and assigned their own field. Relying partially on the University of Pennsylvania’s Historic Cemetery Plot and Marker Survey Form, over 90 different, quantifiable attributes (such as: birth year, death month, gender, age, last name, associated individuals, orientation of individual, marker type, marker height, other associated markers, grade slope, marker exposure, marker material, evident repairs, biogrowth condition, staining, cracking, foundation exposure, erosion level) were selected, with some attributes (i.e., name, death date) employed into both tables.  Surveyors used multi-directional lighting and shading to decipher the wording carved on the older, and more difficult to read, markers. At least two high-resolution photos (with optimum lighting) were taken of each marker to exhibit as many design features as possible (figures 3 and 4). Each marker was also geo-referenced using high resolution aerial photography, and aided by ground measurements. The data from the field was then added to the database in two separate (but linked) tables, one for public outreach and one for resource management.

Figure 3: An example of the detail revealed by using optimum environmental lighting conditions to cast shadows into the previously invisible decorative motifs.

Figure 4: An example of difficult-to-decipher personal information revealed on a weathered marker, using optimum environmental lighting conditions.

Once populated, the database allows for each attribute to be referenced and cross-referenced in a nearly infinite number of ways. Figure 5 offers an example of cross-referencing individuals’ information to examine demographics. Here, average age of death is cross referenced with decade of death and with gender, displaying the average life span of each gender for each decade, as seen in Sheepfold cemetery.  The database can also be used to analyze the markers themselves, via the resource management table.  For instance, cross examining the different marker materials on the basis of their total condition to see which materials weather the best.  In Sheepfold cemetery, ordered from best preservation to worst preservation is:  zinc, granite, ferrous, marble, concrete, and limestone.

Figure 5: Sheepfold Cemetery average age of death by decade and gender. Note: does not include infants (presumed, unnamed), does include vets, each entry is represented by roughly three individuals.
(Image courtesy of the author)

When tied to the geophysical information systems, each marker or individually-related attribute in the database can also be examined in terms of its spatial meaning.  For instance, each marker can now be viewed in terms of when it was placed (earliest death year), and how the individual choosing the plot viewed the other markers and the surrounding landscape. Figure 6 illustrates the result of such an analysis, in Sheepfold cemetery. The burials started in the eastern portion of the cemetery and spread out closer to the road.  It also appears that after the interment of Rachel, a slave-turned- servant of the French aristocratic LeRay family (the northeastern most burial), the interments started to move away from her location more intensively and towards the southwest (until roughly a generation later).

Figure 6: Sheepfold Cemetery Interment Year Distribution (Image courtesy of Mrs. Jaime Marhevsky, Fort Drum DPW-ENV)

In conclusion, Fort Drum has utilized a variety of tools to enhance the management of and public interaction with the 13 historic cemeteries within its borders. The GPR survey offered insights into a previously speculative area, displaying similar anomaly attributes to the known burials. By properly identifying and defining marker attributes, an incredibly powerful tool has been developed for public information, resource management, and subsequent outside research. By geo-referencing the entries, the versatility of this database increases exponentially, allowing for spatial attribute comparisons and easy element location. It is important to remember that these principles may also be applied to other resources, allowing for more efficient management, public information, and data dissemination. Fort Drum’s Cultural Resource Management Program has made huge strides in its cemetery relations and management, continuing to innovate and share this sort of information through its public outreach program, which includes Facebook and Twitter accounts.

What are some applications and benefits of creating geo-referenced databases for other types of sites? (any specific examples?) At what point in the process does the dissemination of information (to the general public and possible researchers) come into play when designing and performing cultural resource management archaeology? (and why so?) What are the benefits and drawbacks of digitizing cultural resources as a means of compliance with the various historic preservation laws?

Read the other contributions for Tech Week, starting with “Understanding Cemeteries through Technical Applications: An example from Fort Drum, NY” by Duane Quates

Tech Week: Underwater and Public Archaeology

Hello SHA blog readers and welcome to a third installment of Tech Week ! This week the SHA Technology Committee is thrilled to focus on underwater archaeology. But not just any underwater archaeology – this week’s bloggers are all concentrating on ways to engage the public through technology. Using technology to interact with the public is a particular concern for underwater archaeologists because the sites we study are generally inaccessible to all but the roughly 1% of Americans who SCUBA dive (the percentage is even lower in many other nations); however, we think this is a topic that should be of interest to all historical archaeologists. The public funds archaeology, the public loves archaeology, but the public does not always understand archaeology. New technologies are making it easier to better explain what we do and why it matters, and this week’s bloggers offer some excellent ideas on how to make the promise of technology a reality.

The week begins with a piece by T. Kurt Knoerl on using the internet to make connections to the ‘global shipwreck.’ As the founder and Chairman of the Museum of Underwater Archaeology, the premier online exhibit space for underwater archaeological projects, Kurt knows what he’s talking about. He argues that the internet should be used to actively engage the public and other archaeologists in collaborative projects.

The second post is by Kimberly Faulk (Geoscience Earth and Marine Services) and Daniel Warren (C & C Technologies), two leaders in the field of deep-water archaeology. Their blog discusses the recent Okeanos Explorer cruise in the Gulf of Mexico. While the technology involved in exploring shipwrecks thousands of feet below the ocean’s surface is amazing, their contribution focuses on something more important: making archaeology real to anyone with an internet connection. Their post not only discusses how technology can create a world of citizen scientists but also how technology can enrich the archaeologist.

Tech Week’s third blogger, Peter Fix, is an archaeological conservator with the Center for Maritime Archaeology and Conservation  and is heading-up the conservation of the 17th century ship La Belle. Peter’s contribution breaks from the internet driven approach of the first two pieces and discusses the technology behind conserving an entire shipwreck so that it can be viewed up-close and personal in a museum.

Finally, rounding out our week and continuing the theme of active public involvement through technology Annalies Corbin and Sheli O. Smith of the PAST Foundation echo the call for active public participation in archaeology. The PAST Foundation uses anthropology to teach science, technology, engineering, and math (STEM), putting Annalies and Sheli on the frontline of public engagement. Their contribution, which looks to the future, is a fitting way to end this Tech Week.