Sensing the Past: Perspectives on Collaborative Archaeology and Ground Penetrating Radar Techniques from Coastal California

Round 1

Reviewer 1 Report

Sanchez and colleagues provide essential work within the context of Remote Sensing. They remind us any remote sensing effort is the most valuable when we integrate the human component. They further push the agenda and build a collaborative effort with indigenous peoples of California. I am hoping to see similar work in this journal which is mainly famous for “sterile” science and engineering studies.

By page number five, there are no line numbers so that I will copy and paste for guidance.

Inline comments:

50. Thanks to the multi-sensor technologies, we are now working on geophysical landscapes. So, the older site-specific paradigm is currently being replaced by very-large area coverage. I understand it is not the case in your region, but please mention these developments.

53. This is related to the comment above. Your narrative suggests that remote sensing in archaeology is a previous natural step to excavations. I would disagree. We are now collecting extensive data from landscapes and able to ask entirely different questions. For your paper, I understand your workflow, but it is not the only workflow. It would also be nice to mention differences for the broader audience.

128. It may be better also to report acres to hectares/square-meter conversion for a larger audience.

Page 6.

“To analyze surface material densities, we applied the kernel density tool from the spatial analyst toolbox and density toolset in ArcMap 10.7”

As a suggestion for the future work, maybe you can consider migrating to non-proprietary software (e.g. QGIS). Especially since you are working with underprivileged communities, their wider access to software is critical.

Page 7.

Figure 2: Legend fonts should be larger. I don’t think you need the labels for points anymore since the reader can match these points using Figure 1. Or at least, you can keep the labels for the points you will discuss later on. Also, you might want to tweak your kernel parameters. I don’t think this is the best way to interpolate your data.

Page 7.

“4.2. Ground-Penetrating Radar”

It is customary to report the processing parameters of the GPR. Please report them.

Page 7.

“which begin in the southwest corner (0N/0E); therefore, transects represent the Y-axis (Figure 3).”

Why don’t you georeference your GPR data (Figure 4) over the map (Figure 3)?

Figure 4.

Please increase the font size. It is hard to read.

Page 9.

Please fully define bd (below datum) for the non-archaeologists

Page 10.

"5. Discussion"

Your work is critical. I firmly believe you should make better use of your case. I want to suggest:

1. a) adding a paragraph for the community (not crowdsourcing) approaches to remote sensing. Brief literature might inform the readers.
2. b) “Archaeological geophysics is now a central approach of the Amah Mutsun when conducting archaeology in their traditional territories.” Could you please inform the reader about the specifics? Did they buy their equipment? Are they collaborating with regional archaeologists? Are they running their education programme to train future archaeologists?

Page 11.

One would also like to see more conclusive discussion on community contribution in your project. Did the community members collect data? Did the community members assist you in making interpretations? Did you run a hands-on training workshop? Without this information, it will be hard to assess the impact of your excellent work on/with the community. After reading your submission, I could not get a full sense of the level of “collaboration”. Offering a complete picture will be extremely beneficial to the readers of Remote Sensing.

Author Response

Comments and Suggestions for Authors

Sanchez and colleagues provide essential work within the context of Remote Sensing. They remind us any remote sensing effort is the most valuable when we integrate the human component. They further push the agenda and build a collaborative effort with indigenous peoples of California. I am hoping to see similar work in this journal which is mainly famous for “sterile” science and engineering studies.

By page number five, there are no line numbers so that I will copy and paste for guidance.

Inline comments:

50. Thanks to the multi-sensor technologies, we are now working on geophysical landscapes. So, the older site-specific paradigm is currently being replaced by very-large area coverage. I understand it is not the case in your region, but please mention these developments.

Authors Response: We have added discussion of landscape level and wide-coverage remote sensing to the discussion (see below). We recognize that the application of remote sensing techniques in California and as advocated for by Lightfoot and as applied in the case-study remains small-scale.

     At this time, the field methodologies advocated by Lightfoot [1] and its application in California have remained site-specific and conducted at a small-scale rather than at the landscape level [2-4,9,11,21]. However, we recognize that landscape-level and wide-coverage remote sensing, integrating various remote sensing techniques that include targeted ground-truthing and excavation of identified features, offer numerous advantages [44-46]. We hope the methods and techniques advocated for in this study and broader landscape-level remote sensing approaches are adopted by researchers in California, tribal organizations, and beyond.

53. This is related to the comment above. Your narrative suggests that remote sensing in archaeology is a previous natural step to excavations. I would disagree. We are now collecting extensive data from landscapes and able to ask entirely different questions. For your paper, I understand your workflow, but it is not the only workflow. It would also be nice to mention differences for the broader audience.

Authors Response: We believe the addition of the section mentioned above addresses this concern. However, it is important to note that the narrative we present, remote sensing is a first step prior to excavation, is accurate in this context, as we are discussing the application of a field methodology advocated for by Lightfoot and applied in California. It may not be widely applied in other regions, but the practice is common in our area.

128. It may be better also to report acres to hectares/square-meter conversion for a larger audience.

Authors Response: We have added the necessary conversions as 80.9 hectares or 809371 m².

Page 6.

“To analyze surface material densities, we applied the kernel density tool from the spatial analyst toolbox and density toolset in ArcMap 10.7”

As a suggestion for the future work, maybe you can consider migrating to non-proprietary software (e.g. QGIS). Especially since you are working with underprivileged communities, their wider access to software is critical.

Authors Response: We thanks the reviewer for this suggestion. Our community partners do have access to ArcGIS but we will explore the use of non-propriety software for future research.

Page 7.

Figure 2: Legend fonts should be larger. I don’t think you need the labels for points anymore since the reader can match these points using Figure 1. Or at least, you can keep the labels for the points you will discuss later on. Also, you might want to tweak your kernel parameters. I don’t think this is the best way to interpolate your data.

Authors Response: Figure 2 has been revised. Fonts were made larger and are at 18 pt. We have left the labels for the surface survey units to be consistent in our reporting and to assist the reader. The kernel parameters were modified to better represent the data as well.

Page 7.

“4.2. Ground-Penetrating Radar”

It is customary to report the processing parameters of the GPR. Please report them.

Authors Response: We have added information regarding the filters used in processing.

Page 7.

“which begin in the southwest corner (0N/0E); therefore, transects represent the Y-axis (Figure 3).”

Why don’t you georeference your GPR data (Figure 4) over the map (Figure 3)?

Authors Response: Given the use of slice maps the georeferencing individual slices is not possible given the number of figures that would be needed to georeference each slice over the grids. 

Figure 4.

Please increase the font size. It is hard to read.

Authors response: We have revised the figures accordingly.

Page 9.

Please fully define bd (below datum) for the non-archaeologists

Authors response: Below datum was defined with the first use of bd in text.

Page 10.

"5. Discussion"

Your work is critical. I firmly believe you should make better use of your case. I want to suggest:

1. a) adding a paragraph for the community (not crowdsourcing) approaches to remote sensing. Brief literature might inform the readers.
2. b) “Archaeological geophysics is now a central approach of the Amah Mutsun when conducting archaeology in their traditional territories.” Could you please inform the reader about the specifics? Did they buy their equipment? Are they collaborating with regional archaeologists? Are they running their education programme to train future archaeologists?

Authors Response: Based on the initial geophysical studies conducted in collaboration with the Amah Mutsun by Cuthrell [1], archaeological geophysics is now a central approach of the Amah Mutsun when conducting archaeology in their traditional territories. Therefore, geophysical techniques are a prerequisite to archaeological field research on ancestral sites and landscapes, and can help other contemporary tribes who remain skeptical of archaeologists reach an ethical approach to conduct an excavation. While the Amah Mutsun do not currently own geophysical survey equipment, they can gather the data needed to make informed decisions regarding subsurface excavations before they occur through their collaboration with academic researchers at various institutions. The collaborative experiences outlined in this paper have demonstrated to the Amah Mutsun the unique advantage that ground penetrating radar studies provide and is thought of as a “non-negotiable” method to be integrated with any invasive form of archaeological research of ancestral sites. However, the development of an Amah Mutsun Land Trust Cultural Resource Management Program is underway, where qualified tribal members lead and carry out archaeological studies in their traditional territories.

Page 11.

One would also like to see more conclusive discussion on community contribution in your project. Did the community members collect data? Did the community members assist you in making interpretations? Did you run a hands-on training workshop? Without this information, it will be hard to assess the impact of your excellent work on/with the community. After reading your submission, I could not get a full sense of the level of “collaboration”. Offering a complete picture will be extremely beneficial to the readers of Remote Sensing.

Authors Response: In the current case study, all fieldwork was conducted by researchers at UC-Berkeley and Michigan State University at the request of the Amah Mutsun Tribal Band. However, research findings from every phase of research (background research, the establishment of survey grid, results of surface survey units, placement and results of ground-penetrating radar, and placement and findings from excavations) were shared with tribal chairman Valentin Lopez and other community members, who were conducting cultural programming and research in the immediate area. We are currently finding ways to integrate tribal members in the Amah Mutsun Land Trust Cultural Resource Management Program in more advanced stages of GPR surveying and data processing. However, it is important to note that Amah Mutsun tribal members have participated in all phases of archaeological research including multiple UC-Berkeley led field schools to assist in community capacity building by having tribal members conduct pedestrian survey, establish survey grids, running geophysical equipment, conducting excavations, processing soil samples via water flotation, and laboratory research since the initiation of the collaborative and community-based research project in 2007 [11]. Nonetheless during the fieldwork reported in this case study, scheduling conflicts made it difficult for tribal stewards to participate due to other projects that were occurring in the study area that included the stewards.

Submission Date

10 November 2020

Date of this review

18 Nov 2020 10:44:35

Reviewer 2 Report

The aim of this study is to summarize over a decade of collaborative eco-archaeological research along the central coast of California involving researchers from different groups and to show the work carried out and preliminary progress.

The subject is of interest, because remote sensing appoarch rarely applied to archaeological prospections for creating bridges through equitable and inclusive research practices between archaeologists and the local community.

I read the submission three times over the past three weeks, in order to be absolutely sure about my recommendation. The manuscript presents an interesting study of employing GNSS and GIS method to document and assess cultural resources threatened by coastal erosion and GPR to identify archaeological deposits, minimize impacts on sensitive cultural resources, and provide tribal and state collaborators with a suite of data to consider before proceeding with any form of invasive archaeological excavation. However, there are several major problems with this manuscript, mainly innovative problems with methods and results from an archaeological perspective.

The paper type should not be article, but perspective or letter. The title of the paper is too broad to focus. GPR can not represent remote sensing, or GPR is only a kind of remote sensing technology.

In general, the contribution of remote sensing in archaeological paper can be either in: (1) new or modified method that is better than previously published; or (2) scientific and archaeological issues uncovered using remote sensing techniques (Optical, SAR, LiDAR, GPR, etc), as is e.g. significant archaeological discovery of the coastal culture/civilization that is missed in the previously published. This paper is not strong enough to demonstrate either of these two possible contributions.

There is not enough methodologically innovative about what they're doing from the perspective of both remote sensing and archaeological sciences. That is not to say that their work is not important-there is a dearth of technical innovation in remote sensing and refreshing opinions in archaeology.

In its present form, I wonder if the subject of this paper is really adapted to RS, a top peer-reviewed journal in remote sensing.

Author Response

Comments and Suggestions for Authors

The aim of this study is to summarize over a decade of collaborative eco-archaeological research along the central coast of California involving researchers from different groups and to show the work carried out and preliminary progress.

The subject is of interest, because remote sensing approach rarely applied to archaeological prospections for creating bridges through equitable and inclusive research practices between archaeologists and the local community.

I read the submission three times over the past three weeks, in order to be absolutely sure about my recommendation. The manuscript presents an interesting study of employing GNSS and GIS method to document and assess cultural resources threatened by coastal erosion and GPR to identify archaeological deposits, minimize impacts on sensitive cultural resources, and provide tribal and state collaborators with a suite of data to consider before proceeding with any form of invasive archaeological excavation. However, there are several major problems with this manuscript, mainly innovative problems with methods and results from an archaeological perspective.

The paper type should not be article, but perspective or letter. The title of the paper is too broad to focus. GPR can not represent remote sensing, or GPR is only a kind of remote sensing technology.

In general, the contribution of remote sensing in archaeological paper can be either in: (1) new or modified method that is better than previously published; or (2) scientific and archaeological issues uncovered using remote sensing techniques (Optical, SAR, LiDAR, GPR, etc), as is e.g. significant archaeological discovery of the coastal culture/civilization that is missed in the previously published. This paper is not strong enough to demonstrate either of these two possible contributions.

There is not enough methodologically innovative about what they're doing from the perspective of both remote sensing and archaeological sciences. That is not to say that their work is not important-there is a dearth of technical innovation in remote sensing and refreshing opinions in archaeology.

In its present form, I wonder if the subject of this paper is really adapted to RS, a top peer-reviewed journal in remote sensing.

Authors response: We much appreciate the reviewer's perspective and comments. While there were no specific points raised that could be used to strengthen the present submission—the reviewer is adamant that our study has no methodological innovation and is not worthy of publication in Remote Sensing. However, we would like to note that methods are only a component of scientific research. A significant consideration of contemporary archaeological practice is how and for whom are studies being conducted.

We believe we offer a perspective of how collaborative and community-engaged archaeology guided by remote sensing technologies—in this case, applying GPR methodologies, which is a remote sensing technique—can heal historical trauma caused by the field of archaeology, build trust between indigenous peoples and archaeologists, and identify common concerns, such as the persistence of indigenous anadromous salmonids, to conduct ethical archaeology of relevancy to a variety of stakeholders.

Reviewer 3 Report

In this work, the authors present the results of an interesting research carried out in the Quiroste Valley by applying GPR method.

Overall, it could be a good case study of integrated image detection. However, I think the paper would benefit from clarifications; there are several aspects of your research that need to be explained.

Please, consider the points hereinafter.

1.  I’d suggest to include in the background, section 2.1, the results provided by previous geophysical studies in this zone.

2.  Figure 1: I understand that it is important to protect the exact location, but please add the geographical coordinates to the California coast map and to the map of the project area.

3. Please explain in more detail why you chose this location for the GPR grids.

4. I think it is necessary additional information about GPR data processing. In particular, did you applied some filter?

5. Figure 4 and 5: Please, add numeric values to the scale bar. On the other hand, the figure 5 is too small.

6. Please, show some individual transect files.

7. Grid 1: what about the high amplitudes centered at x= 3-4 m, y = 1-2 m? They are present in slice 2, 3 and 4

8. Grid 2: How would you explain the high amplitudes present in slice 9?I’d suggest to explain in the text the comment that appears in the figure about shallow reflections. 

9. I think that the EU1 does not match the selected anomaly in slice 5.

10. The discussion must be improved with a deeper analyses of the results from GPR method. It would be interesting to compare with the results from previous geophysical studies in the region.

Author Response

"Please see the attachment."

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

1. Figure 1: Bottom: the geographical coordinates do not correspond to this zone. Please add the geographical coordinates only to the California coast map and to the map of the project area.

2. Figure 4 and 6: Please, add numeric values to the scale bar or indicate it in the figure caption.

Author Response

1. Figure 1: Bottom: the geographical coordinates do not correspond to this zone. Please add the geographical coordinates only to the California coast map and to the map of the project area.

Authors response: Geographical coordinate for the inset California map is now places on the left and top of the figure and project area coordinates were added to the right and bottom of insets. 

2. Figure 4 and 6: Please, add numeric values to the scale bar or indicate it in the figure caption.

Authors response:We added these data to the caption: "Scale represents the gains-adjusted amplitude time slice parameter for 32-bit data."