Geophysical methods applied in Archaeology: first results from Capelinha fluvial sambaqui, Cajati-SP, Brazil.

The increasing application of geophysical methods in archaeological prospecting is due to the need of efficient and non-destructive investigations. This work shows how geophysical prospecting could aid archaeological investigations in the Capelinha site, located at Cajati (São Paulo, Brazil). This site is a fluvial sambaqui with a very discreet surface topography response. Magnetometry and georadar (GPR) were used to identify the main archaeological targets. An important result is the localization of a paleobonfire that, at the moment, is unique at the site, with arrow heads, bones, among other materials associated and an excavation-fill structure.A utilização de métodos geofísicos em prospecções arqueológicas é crescente e se deve à necessidade, cada vez maior, de uma investigação mais eficiente e não destrutiva. Este trabalho mostra como as prospecções geofísicas puderam auxiliar as investigações arqueológicas no Sítio Capelinha. A área prospectada é um sambaqui fluvial, muito discreto na topografia, situado em Cajati (São Paulo, Brasil). Os métodos de magnetometria e georadar (GPR) localizaram os alvos com maior potencial arqueológico, como, por exemplo, uma paleofogueira, que até o presente momento é única em todo o sítio, com pontas de flecha e restos ósseos associados e uma estrutura de escavação-preenchimento

3D model evolution of a leak based on GPR image interpretations

This paper presents some aspects of the time propagation of underground water leakage in controlled laboratory conditions using a drilled polyvinyl chloride (PVC) pipe and interpreting ground penetrating radar (GPR) images. GPR pre-processed images are interpreted for easy identification and extraction of surfaces and volumes of water leakage. Finally, the temporal evolution of a water leak is shown using 3D models based on interpretation of GPR images. Water volumes obtained using this approach can be easily observed by personnel who lack highly specialized training in the analysis of raw data. The results of this study are promising and can help develop techniques to validate non-destructive models for the identification, distribution, and prediction of water leaks in water supply systems using GPR.Part of this work has been developed under the support of an FPI (Formacion de Personal Investigador)-UPV (Universitat Politecnica de Valencia) scholarship granted to the second author by the Programa de Ayudas de Investigacion y Desarrollo (PAID) of the Universitat Politecnica de Valencia, and the support of Fundacion Carolina PhD, within its short stances scholarship program for the first author. The use of English in this paper has been revised by John Rawlins.Ocana-Levario, S.; Ayala Cabrera, D.; Izquierdo Sebastián, J.; Pérez García, R. (2015). 3D model evolution of a leak based on GPR image interpretations. Water Science and Technology: Water Supply. 15(6):1312-1319. doi:10.2166/ws.2015.093S1312131915

Methodology for geophysical surveying in archaeology: notes on fieldwork at Iesso, Can Tacó, Molins Nous and El Goleró

Las prospecciones geofísicas aplicadas a la arqueología tienen por objetivo ayudar a la investigación aportando datos y elementos que permiten una gestión más eficaz del patrimonio arqueológico. Pero, para que los resultados de estas prospecciones sean realmente útiles, se deben tomar ciertos cuidados en el procedimiento. El presente artículo trata de describir una metodología para llevar a cabo el trabajo de campo con éxito. Aquí trataremos algunos estudios de caso de las prospecciones geofísicas en los yacimientos arqueológicos de Iesso (Guissona – Lleida), Can Tacó (Montmeló – Barcelona), El Goleró (Alt Urgell – Lleida) y Molins Nous (Riudoms, Baix Camp – Tarragona) realizadas en 2006.Geophysical surveys in archaeology are intended to help researchers by supplying data and information that will allow the archaeological heritage to be managed more effectively. However, for the results to be really useful care needs to be taken during fieldwork. This paper describes a methodology for carrying out successful fieldwork. We look at some case studies of geophysical surveys at the archaeological sites of Iesso (Guissona – Lleida), Can Tacó (Montmeló – Barcelona), El Goleró (Alt Urgell – Lleida) and Molins Nous (Riudoms, Baix Camp – Tarragona)

Seismic velocity anomalies beneath SE Brazil from and wave travel time inversions

We present the result from teleseismic travel time inversions for P and S wave data mainly recorded at portable broadband stations in SE Brazil. The stations were deployed at 45 sites within an area 1000 × 1700 km during the years 1992–1999. More than 10,000 relative P and S wave arrival times, including core phases, were obtained from the waveforms using a new coherence functional. These P and S relative phase times are independently inverted for slowness perturbations, earthquake relocations, and station corrections. The final models represent the least amount of structure required to explain the residuals within a defined standard error. The robust and consistent features in the velocity anomaly models are interpreted and their resolution is tested with synthetic case inversions. We confirm the existence of a cylindrical low-velocity anomaly beneath the Paraná basin, which has been interpreted by VanDecar et al. [1995] as the fossil conduit through which the initial Tristan da Cunha plume head traveled to generate the Paraná–Etendeka flood basalts about 130 Ma. We now show that this low-velocity cylindrical structure seems to be confined to the upper mantle. Beneath the upper mantle, the velocity anomalies show a N-S oriented pattern, which we interpret as due to the Nazca plate subducted slab. At lithospheric depths, the Archean, southern part of the São Francisco craton, shows high velocities down to 200–300 km. All areas with Late Cretaceous postrift alkaline intrusions are characterized by low velocities at lithospheric depths.Peer reviewe

Mobile genes in the human microbiome are structured from global to individual scales

Recent work has underscored the importance of the microbiome in human health, and has largely attributed differences in phenotype to differences in the species present among individuals. However, mobile genes can confer profoundly different phenotypes on different strains of the same species. Little is known about the function and distribution of mobile genes in the human microbiome, and in particular whether the gene pool is globally homogenous or constrained by human population structure. Here, we investigate this question by comparing the mobile genes found in the microbiomes of 81 metropolitan North Americans with those of 172 agrarian Fiji islanders using a combination of single-cell genomics and metagenomics. We find large differences in mobile gene content between the Fijian and North American microbiomes, with functional variation that mirrors known dietary differences such as the excess of plant-based starch degradation genes found in Fijian individuals. Notably, we also observed differences between the mobile gene pools of neighbouring Fijian villages, even though microbiome composition across villages is similar. Finally, we observe high rates of recombination leading to individual-specific mobile elements, suggesting that the abundance of some genes may reflect environmental selection rather than dispersal limitation. Together, these data support the hypothesis that human activities and behaviours provide selective pressures that shape mobile gene pools, and that acquisition of mobile genes is important for colonizing specific human populations.National Human Genome Research Institute (U.S.) (Grant U54HG003067)Broad Institute of MIT and HarvardMassachusetts Institute of Technology. Center for Environmental Health SciencesMassachusetts Institute of Technology. Center for Microbiome Informatics and TherapeuticsFiji. Ministry of HealthColumbia Earth Institute (Institute Fellowship