John Van Hoesen

CARACTERIZACIÓN QUÍMICA Y MINERALÓGICA DE LOS MATERIALES GRISES DE LOS CUERPOS CHINCHORRO MODELADOS

En este trabajo se investiga la composicion quimica y mineralogica de los materiales arcillosos grises utilizados por las poblaciones Chinchorro en la creacion de las llamadas Momias Negras (cuerpos modelados). En particular, se analiza y cuantifica si este tipo de material corresponde a arcilla, cual es su composicion mineralogica y cual es su calidad plastica. Para ello se seleccionaron micro-muestras de material gris de relleno de 13 Momias Negras de Arica (ca. 4.000-2.800 a.C.), las que se analizaron en el Laboratorio de Investigaciones Medioambientales de Zonas Aridas, LIMZA (CIHDE-UTA, Universidad de Tarapaca), utilizando Espectrometria de Fluorescencia de Rayos X de Energia Dispersiva (EDXRF) y en el Laboratorio de Ciencias Geologicas de la Universidad del Norte, Antofagasta, mediante Difraccion de Rayos X (DRX) y microscopia electronica de barrido. Ademas se realizaron pruebas de ceramologia experimental en el Laboratorio de Conservacion del Museo Arqueologico, Universidad de Tarapaca, Arica. Los resultados obtenidos por la tecnica EDXRF indican que el material gris esta compuesto principalmente por SiO2 (68%), Al2O3 (13%), Fe2O3 (7%) y, en menor proporcion, K2O (4%), CaO (3%), Cl (2%), SO3 (1%), y TiO2 (1%). Los analisis obtenidos por DRX demostraron que la composicion mineralogica estaba constituida por cuarzo (30%), albita (26%), sanidina (15%) y moscovita (12%), entre otros. Estos resultados, en conjunto con los analisis experimentales ceramologicos y microscopicos, permiten concluir que las poblaciones Chinchorro utilizaban sedimentos naturales que pueden ser considerados como arcillas de buena a mediana calidad plastica para preparar sus Momias Negras y que no le agregaban inclusiones como conchuela o fibras vegetales.

A Geographic Information Systems (GIS)-Based Approach to Derivative Map Production and Visualizing Bedrock Topography within the Town of Rutland, Vermont, USA

Many state and national geological surveys produce map products from surficial and bedrock geologic maps as a value-added deliverable for a variety of stakeholders. Improvements in powerful geostatistical exploratory tools and robust three-dimensional capabilities within geographic information systems (GIS) can facilitate the production of derivative products. In addition to providing access to geostatistical functions, many software packages are also capable of rendering three-dimensional visualizations using spatially distributed point data. A GIS-based approach using ESRI’s® Geostatistical Analyst® was used to create derivative maps depicting surficial overburden, bedrock topography, and potentiometric surface using well data and bedrock exposures. This methodology describes the importance and relevance of creating three-dimensional visualizations in tandem with traditional two-dimensional map products. These 3D products are especially useful for town managers and planners—often unfamiliar with interpreting two-dimensional geologic map products—so they can better visualize and understand the relationships between surficial overburden and potential groundwater resources.

Characterizing the Spatiotemporal Evolution of Building-Stock Age in Poultney, Vermont: A GIS-Based Approach to Improve Thermal Efficiency in Historical Buildings

Many industrialized countries are exploring ways to facilitate the prioritization of efforts targeting improved thermal efficiency in an aging building stock. Older buildings, typically, have inefficient building envelopes and higher energy-consumption patterns relative to new construction, which contributes to higher overall energy consumption at the local and regional scale. Reducing energy consumption by increasing the efficiency of older buildings will result in lower anthropogenic greenhouse gas emissions and help address the growing issues related to climate change. To address these concerns a GIS-based approach is developed to evaluate building-stock age in rural communities with limited access to historical parcel data. This approach involves georeferencing historical Sanborn insurance maps, digitizing building footprints for each year. This methodology is applied to a small town in rural Vermont and a map is produced depicting the spatiotemporal evolution of building construction over the years 1885–1940. 1091 structures built prior to 1941 are identified and it is argued that weatherization efforts should focus on the oldest buildings first and sequentially address younger structures, lowering both energy consumption and greenhouse gas emissions associated with the least-efficient building stock.

The Morphology and Spatial Distribution of Late Quaternary Periglacial Landforms, Snake Range, Nevada: A Gis-Based Approach to Prioritizing Field Sites

ABSTRACT We present new data describing relict periglacial landforms preserved in the interior Great Basin of the southwestern United States. This summary is significant because a thorough understanding of the occurrence and spatial distribution of these landforms is still lacking after 60 years of geomorphic studies in this region. This is largely because many landforms are often un-recognized and because many mountains in the Great Basin are remote and offer poor access. To help address this knowledge gap, we use a GIS with high-resolution imagery and field mapping to identify and describe features that indicate a locally extensive periglacial environment existed in the Snake Range of east-central Nevada during the Late Quaternary. We also compare the location of these landforms with solar radiation models produced using ESRIs Solar Analyst to evaluate the efficacy of using solar modeling as means to predict suitable field sites for periglacial landforms. This simple modeling technique accurately identifies the location of known periglacial landforms in the Snake Range and therefore we believe it could be used to prioritize sites of interest throughout the Great Basin.

Living in poisoning environments: Invisible risks and human adaptation

This article describes the hidden natural chemical contaminants present in a unique desert environment and their health consequences on ancient populations. Currently, millions of people are affected worldwide by toxic elements such as arsenic. Using data gathered from Atacama Desert mummies, we discuss long‐term exposure and biocultural adaptation to toxic elements. The rivers that bring life to the Atacama Desert are paradoxically laden with arsenic and other minerals that are invisible and tasteless. High intake of these toxic elements results in severe health and behavioral problems, and even death. We demonstrate that Inca colonies, from Camarones 9 site, were significantly affected by chemical contaminants in their food and water. It appears however, some modern‐day Andean populations resist the elevated levels of arsenic exposure as a result of positive selection mediated via the arsenic methyltransferase enzyme and display more tolerance to high chemical doses. This article further debate the effects of natural pollution and biocultural adaptation of past populations.

USING PHOTOGRAMMETRY TO ANALYZE STRUCTURES IN A TECTONIC SLIVER IN THE FOOT WALL OF THE CHAMPLAIN THRUST, SHELBURNE, VERMONT

S1 pressure-solution cleavage (green) in SP2 below Fault B. Note bedding(S0) (blue) in the microlithons that makes a pronounced intesection lineation (L1) on S1. S1 pressure-solution cleavage on the western side of SP5 that was deformed by open F2 folds. Note bedding(S0) in the microlithons. S1 pressure-solution cleavage on the eastern side of SP5 that was deformed by tight F2 folds. Note bedding(S0) in the S1 microlithons and the S2 fracture cleavage that is axial planar to the F2 folds and fortuitously parallel to S0. S1 pressure-solution cleavage on the central part of SP5 that was deformed by very tight F2 folds. Note that bedding(S0) in the S1 microlithons (parallel to pen) is now subvertical.