Spatial Analysis and Remote Sensing

Images and Geospatial Analysis in Colonial Huarochirí

Using a parrot sequoia camera we mapped abandoned agricultural fields in Tupicocha, Huarochirí. Band combination from the ortho mosaic.

My research combines large-scale multispectral remote sensing (RS) techniques using high-resolution satellite imagery, archaeological survey, and archival research, to investigate the colonial landscape of the central highlands of Peru, and how indigenous communities negotiated the creation of new post-Toledan settlements. The methodological novelty of this project centers Land-Use and Land-Cover (LULC) analysis of large-scale multispectral satellite imagery to detect and characterize anthropogenic anomalies such as abandoned and unabandoned agricultural infrastructure using semi-automated RS classification. To tie these large-scale characterizations back to ground truth, I will conduct targeted archaeological survey along with UAV-based survey (using UAVs from the Spatial Analysis Research Laboratory [SARL] of Vanderbilt University) to acquire close-range, high-resolution remote sensing imagery. In this way, I envision an integrated multi-scalar “stack” for characterizing colonial era LULC.

Land-Use and Land-Cover (LULC) analysis of large-scale multispectral satellite imagery

Overview: I will use LULC RS analysis to detect and map agricultural terraces, irrigation systems and settlements in area 500 km2 area in the upper Lurín Valley. I have already identified the appropriate specific satellite World View 2 images for this area. I will use and refine my established workflow for supervised classification and feature detection. First, I will perform an initial satellite image analysis of 100 sq. km. between the towns of Tupicocha and San Damian. Then I will ground-truth my findings with a full-coverage archaeological survey of the same area. The results will provide data to improving the LULC algorithm, which I will then apply to the rest of the area of interest (the remaining 400 km2).

Analysis of multispectral imagery: I have already successfully developed an anomaly detection LULC workflow using this class of imagery within an initial pilot project area (Oré and Chase 2017). I use a sequence of Independent Component Analysis (ICA) and Anomaly Detection (AD). The results from results from the ICA generates buffered polygons which then acts as a mask for the AD classification. This workflow permits identification of anthropogenic features in the landscape. This workflow enables the identification and differentiation of abandoned and unabandoned terrace and canal systems. Abandoned vs unabandoned terraces are distinguishable in the LULC output by the signature of their overlying vegetation. Subsequent modeling using the results from the LULC/AD analysis will enable construction of a site suitability model on a regional scale.

My RS analysis is a three-stage process. During the first stage, I will refine the workflow to analyze images from a section of my research area, 100 sq. km. between Tupicocha and San Damian. I will use the pedestrian survey data and the close-range UAV data to establish ground truth and to refine my LULC/AD scheme. The second stage, I will apply the LULC/AD analysis to the satellite and UAV data. And in the third stage I will build a suitability model to characterize what the post-Toledan villages have in common in terms of location attributes throughout the upper Lurín. I have already tested this methodology, gaining understanding of the adjustments needed (Oré 2016; Oré and Chase 2017).

Buffered anomalies masked. Analysis over world view 2 image.

Unsupervised classification. Classes are indicating walls from terraces (blue) and walls from archaeological sites and structures (red)

Presentations related to Remote Sensing

Presentations related to Spatial Analysis

Obscure connections: Movements dynamics based on circuit Analisis in the Chillón, Rímac, Lurín and Mala valleys during the Inka Period. Paper presented at the One Empire, multiple spaces: perspectives on Inka archaeology spatial analyses. Ministry of Culture, Lima, Peru.

El uso del Qhapac Ñan como eje de articulación intrarregional deja poco espacio para considerar otras dinámicas de movimiento dentro de una misma región. Si a esto sumamos el desmesurado uso de análisis espacial basado en Least Cost Path (ruta óptima o ruta de coste mínimo - LCP) la manera en la que entendemos el espacio queda restringida a una vista unidireccional. En este sentido voy a usar un tipo de análisis espacial basado en teoría de circuitos. El análisis de circuitos usa como premisa la resistividad y conectividad del terreno desde un punto hacia el resto del espacio circundante. Este análisis permite establecer áreas más conectadas versus áreas menos conectadas. Voy a aplicar análisis de circuitos y contrastarlo con LCP y las rutas del Qhapac Ñan para establecer otras áreas de interacción que han pasado desatendidas en la larga historia de la arqueología inca. Centraré mi análisis alrededor de los valles de Chillón, Rímac, Lurín y Mala. Estos valles presentan, especialmente en la parte alta, una intensa dinámica de movimiento inter-valle. La exploración de rutas alternativas entre sitios inca de estos valles dará una perspectiva diferente de lo que hasta ahora hemos tomado como verdad inamovible.

Circuit analysis between equivalent points in the central valleys in Peru.

Least Coast Path between the same points

Obscure conections: Movements dynamics based on circuit Analisis in the Chillón, Rímac, Lurín and Mala valleys during the Inka Period.

You can watch the talk "Conexiones obscuras: dinámicas de movimiento basadas en análisis de circuitos en los valles de Chillón, Rímac, Lurín y Mala durante el periodo Inka" following the link to the Facebook page: SIMPOSIO: “Un imperio, múltiples espacios; análisis espaciales en arqueología inca” (