Grids And Coordinates

Latitude lines run east-west and are parallel to each other. If you go further north north, latitude values increase. Finally, latitude values (Y-values) range between -90 and +90 degrees

But longitude lines run north-south. They converge at the poles. And its X-coordinates are between -180 and +180 degrees.

Latitude and longitude coordinates make up our geographic coordinate system.

Map Coordinate Systems You can give anything on Earth latitude and longitude coordinates.

The field of study that measures the shape and size of the Earth is geodesy. Geodesists use coordinate reference systems such as WGS84, NAD27 and NAD83. In each coordinate system, geodists use mathematics to give each position on Earth a unique coordinate.

A geographic coordinate system defines two-dimensional coordinates based on the Earth’s surface. It has an angular unit of measure, prime meridian and datum (which contains the spheroid).

As shown in the image below, lines of longitude have X-coordinates between -180 and +180 degrees.

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Grid Services for E-Archaeology

Abstract

Archaeological data collection is based on the description of archaeological contexts. An archaeological excavation demolishes the original matrix within which the cultural material is found and special care is taken to record spatial context. Each artifact is described in terms of its physical and spatial properties as well as its relation to the matrix (for example soil composition). As several thousands of artifacts can be unearthed during a field season, there is a need to develop digital resources and collections that focus on the publication and preservation of data and the creation of tools for the analysis of these data. The first section of this paper presents preliminary results and the lessons learnt on the development of a prototype for an Australian archaeological digital collection based on data grid middleware and infrastructure. The second section introduces a versatile 3D reconstruction tool that visualizes the excavated archaeological artifacts with its associated stratigraphy. The data come from two major archaeological projects in Queensland, Australia: the Mill Point Archaeological...

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Interfaces: Mobile GIS in archaeological survey

You are surveying a broad, featureless plain and the planned coverage area is delimited in a Geographic Information System (GIS), but how do you rapidly locate your starting position and line up your survey crew with few landmarks? Your Global Positioning System (GPS) will get you to the survey area, but figuring out the coordinates is time consuming. Ideally, local maps and imagery, the survey coverage area, and yesterday’s coverage are available on a screen with your current GPS position indicated. You have discovered a site consisting of lithic concentrations of different material types, and each looks like a distinctive reduction event, but you only have 45 minutes to record and collect at the site. Using common GPS methods, you can map each concentration as a polygon feature, assign an ID number to it, document and collect it, and attribute it later. Alternately, you open the “lithic locus” geometry in a mobile GIS and map in each concentration. The GIS assigns a new ID number to the locus,..

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On-Site GIS Digital Archaeology

The 1990s witnessed the progressive ‘miniaturization’ of personal computers and other digital devices. This affected virtually every type of business, research program, as well as the daily lives of millions of people around the world with access to electricity. The development of portable high-speed personal computers and other data collecting devices was not lost on archaeologists who have always had a deep interest in utilizing technological and scientific methods to advance their recording and study of the past (Renfrew and Bahn 2004). In 1997, when the University of California, San Diego initiated the deep-time study of ancient metallurgy and social evolution in Jabal Hamrat Fidan (JHF) region of the Faynan district in southern Jordan, a fairly traditional style of ‘analogue’ or paper archaeological recording was carried out during the first season of excavation. With the exception of using a very expensive Sony video camera for taking digital still photographs of...

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