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Aproximación sistémica al visionado de televisión de sistemas interaccionales familiares de bajo ingreso en Santiago de Chile

Universidad de Chile
  • AntropolóGia.


Gotland University Press 11 87 GIS Applications in Easter Island: Geodetic Adjustments and Survey Maps Accuracy Patricia Vargas, Claudio Cristino & Roberto Izaurieta University of Chile Abstract - This paper discusses the variables and methodology involved in the geodetic transformations required for the adjustment of the Easter Island Archaeological Survey's cartography — until recently supposed to be Datum Easter Island 1967 — into the current world geodetic system, WGS84, base of the NAVSTARGPS system, and explores the limitations for archaeological fieldwork of the absolute method used by the "satellite navigators" in relation with the cartographic scales considered. Recent research on Easter Island involving local surveys done with GPS technology, led some scholars to speculate that the maps of the island- wide archaeological surveys done in 1968 are inaccurate when data are compared with GPS-generated georeferenced locations of geographical features and archaeological features and sites. This paper discusses the true nature of the problem, warns about indiscriminate use and current limitations of GPS surveying on the island without the control and corrections we analyse and — by validating the accuracy of the published survey cartography — proposes the procedures required to make such adjustments to be able to use the archaeological survey's site locations maps. The cartographic base on which the Easter Island Archaeological Survey1 is sustained comes from an analogical aerophotogrammetric restitution executed at 1:10,000 scale, carried out by SAP2 in July 1965, based on aerial photographs taken in January 1964 at an average scale of 1:17,500 (effective at sea level). Its georeference corresponds to an astronomical datum, supposedly established over the "1924 International Ellipsoid". Such restitution, with a 5 m contour interval, constitutes a detailed registry of the morphological features and historic

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