Misplaced Pages

#817182

96-659: Polish archaeologists have worked at the site since 1998. Banganarti was included in the field prospection carried out as part of the Southern Dongola Reach Survey, directed by Bogdan Żurawski, after which started the excavations (in 2001). Earlier, from 1984, the site was studied by an expedition from the Royal Ontario Museum . The Polish expedition is organized by the Polish Centre of Mediterranean Archaeology University of Warsaw ,

192-504: A ground sample distance of 1 inch (2.54 cm) in only 12 minutes. The majority of digital data currently comes from photo interpretation of aerial photographs. Soft-copy workstations are used to digitize features directly from stereo pairs of digital photographs. These systems allow data to be captured in two and three dimensions, with elevations measured directly from a stereo pair using principles of photogrammetry . Analog aerial photos must be scanned before being entered into

288-409: A spatial database ; however, this is not essential to meet the definition of a GIS. In a broader sense, one may consider such a system also to include human users and support staff, procedures and workflows, the body of knowledge of relevant concepts and methods, and institutional organizations. The uncounted plural, geographic information systems , also abbreviated GIS, is the most common term for

384-409: A "real" physical location or extent. This key characteristic of GIS has begun to open new avenues of scientific inquiry and studies. While digital GIS dates to the mid-1960s, when Roger Tomlinson first coined the phrase "geographic information system", many of the geographic concepts and methods that GIS automates date back decades earlier. One of the first known instances in which spatial analysis

480-596: A GIS database, which can be grouped into three categories: primary data capture , the direct measurement phenomena in the field (e.g., remote sensing , the global positioning system ); secondary data capture , the extraction of information from existing sources that are not in a GIS form, such as paper maps, through digitization ; and data transfer , the copying of existing GIS data from external sources such as government agencies and private companies. All of these methods can consume significant time, finances, and other resources. Survey data can be directly entered into

576-567: A GIS for both kinds of abstractions mapping references: raster images and vector . Points, lines, and polygons represent vector data of mapped location attribute references. A new hybrid method of storing data is that of identifying point clouds, which combine three-dimensional points with RGB information at each point, returning a 3D color image . GIS thematic maps then are becoming more and more realistically visually descriptive of what they set out to show or determine. GIS data acquisition includes several methods for gathering spatial data into

672-551: A GIS from digital data collection systems on survey instruments using a technique called coordinate geometry (COGO). Positions from a global navigation satellite system ( GNSS ) like the Global Positioning System can also be collected and then imported into a GIS. A current trend in data collection gives users the ability to utilize field computers with the ability to edit live data using wireless connections or disconnected editing sessions. The current trend

768-500: A Nubian king protected by an Archangel surrounded by the Apostles are typical. Biblical scenes and depictions of secular figures (rulers and high dignitaries) are also common. Medieval fortifications built of mudbrick, showing evidence of two fires in the walls’ layers, as well as the remains of a settlement surrounding the sacral buildings, were also studied. Survey (archaeology) In archaeology , survey or field survey

864-478: A full suite of capabilities for entering, managing, analyzing, and visualizing geographic data, and are designed to be used on their own. Starting in the late 1990s with the emergence of the Internet , as computer network technology progressed, GIS infrastructure and data began to move to servers , providing another mechanism for providing GIS capabilities. This was facilitated by standalone software installed on

960-507: A geographic methodology in pinpointing the source of an outbreak in epidemiology. While the basic elements of topography and theme existed previously in cartography , Snow's map was unique due to his use of cartographic methods, not only to depict, but also to analyze clusters of geographically dependent phenomena. The early 20th century saw the development of photozincography , which allowed maps to be split into layers, for example one layer for vegetation and another for water. This

1056-449: A map made against a local datum may not be the same as one obtained from a GPS receiver . Converting coordinates from one datum to another requires a datum transformation such as a Helmert transformation , although in certain situations a simple translation may be sufficient. In popular GIS software, data projected in latitude/longitude is often represented as a Geographic coordinate system . For example, data in latitude/longitude if

SECTION 10

#1732771914818

1152-910: A mobile GIS for referencing, for sampling purposes, and for groundtruth updating directly in the field, resulting a more informed archaeological survey process. Fieldwalking involves picking up scattered artifacts in ploughed fields. In heavily wooded areas such as Scandinavia or the North American Northeast, or deeply alluviated areas as in the Netherlands, fieldwalking is not always a practical method. Humus and fallen leaves in forested areas, silt on alluvial fans, or turf in built-up neighbourhoods may render near-surface artifacts and sites invisible even at short distances. In such instances, archaeological surveyors may concentrate on above-ground structures such as burial cairns, collapsed field walls and rock art panels, look for unnatural changes in

1248-410: A new dimension to business intelligence termed " spatial intelligence " which, when openly delivered via intranet, democratizes access to geographic and social network data. Geospatial intelligence , based on GIS spatial analysis, has also become a key element for security. GIS as a whole can be described as conversion to a vectorial representation or to any other digitisation process. Geoprocessing

1344-422: A particular locale. It is usually a simple matter to gain permission to perform a cultural field survey, especially a non-intrusive one. If the area is privately owned, the local laws may or may not require the landowners' co-operation. Permission for an intrusive form of survey may be more difficult to acquire, due to the fear of destroying evidence or property values and the threat of lawsuit for said damages from

1440-400: A particular site or a particular kind of archaeological material. For example, they might be searching for a particular shipwreck or an historic fort whose exact location is no longer certain. However, they may also be searching for archaeological materials in particular locations to test hypotheses about past use of those spaces. Sampling surveys , on the other hand, have the goal of obtaining

1536-492: A range of techniques is selected to be applied within an appropriate overarching method. An area may be considered worthy of surveying based on the following: Map regression, comparing maps from different periods of the same area, can reveal past structures that were recorded but are no longer visible as surface features. Using modern maps to transcribe or re-project earlier maps can help to locate these features with contemporary survey controls and techniques. Aerial photography

1632-998: A relational database containing text or numbers can relate many different tables using common key index variables, GIS can relate otherwise unrelated information by using location as the key index variable. The key is the location and/or extent in space-time. Any variable that can be located spatially, and increasingly also temporally, can be referenced using a GIS. Locations or extents in Earth space–time may be recorded as dates/times of occurrence, and x, y, and z coordinates representing, longitude , latitude , and elevation , respectively. These GIS coordinates may represent other quantified systems of temporo-spatial reference (for example, film frame number, stream gage station, highway mile-marker, surveyor benchmark, building address, street intersection, entrance gate, water depth sounding, POS or CAD drawing origin/units). Units applied to recorded temporal-spatial data can vary widely (even when using exactly

1728-443: A representative sample of some population of sites or artifacts in order to make generalizations about that population. This involves some probability sampling of spatial units, such as random or stratified random sampling of geometrical (often square) or irregular spatial units. Conventionally, fieldwalking in grids or along lines called transects has formed the backbone of archaeological survey fieldwork, at least where visibility

1824-502: A result of this, Tomlinson has become known as the "father of GIS", particularly for his use of overlays in promoting the spatial analysis of convergent geographic data. CGIS lasted into the 1990s and built a large digital land resource database in Canada. It was developed as a mainframe -based system in support of federal and provincial resource planning and management. Its strength was continent-wide analysis of complex datasets . The CGIS

1920-479: A road network, lines must connect with nodes at an intersection. Errors such as undershoots and overshoots must also be removed. For scanned maps, blemishes on the source map may need to be removed from the resulting raster . For example, a fleck of dirt might connect two lines that should not be connected. The earth can be represented by various models, each of which may provide a different set of coordinates (e.g., latitude, longitude, elevation) for any given point on

2016-449: A scale of 1:50,000. A rating classification factor was also added to permit analysis. CGIS was an improvement over "computer mapping" applications as it provided capabilities for data storage, overlay, measurement, and digitizing /scanning. It supported a national coordinate system that spanned the continent, coded lines as arcs having a true embedded topology and it stored the attribute and locational information in separate files. As

SECTION 20

#1732771914818

2112-492: A server, similar to other server software such as HTTP servers and relational database management systems , enabling clients to have access to GIS data and processing tools without having to install specialized desktop software. These networks are known as distributed GIS . This strategy has been extended through the Internet and development of cloud-based GIS platforms such as ArcGIS Online and GIS-specialized software as

2208-498: A service (SAAS), and mobile computing . The distinction must be made between a singular geographic information system , which is a single installation of software and data for a particular use, along with associated hardware, staff, and institutions (e.g., the GIS for a particular city government); and GIS software , a general-purpose application program that is intended to be used in many individual geographic information systems in

2304-508: A service (SAAS). The use of the Internet to facilitate distributed GIS is known as Internet GIS . An alternative approach is the integration of some or all of these capabilities into other software or information technology architectures. One example is a spatial extension to Object-relational database software, which defines a geometry datatype so that spatial data can be stored in relational tables, and extensions to SQL for spatial analysis operations such as overlay . Another example

2400-548: A soft-copy system, for high-quality digital cameras this step is skipped. Satellite remote sensing provides another important source of spatial data. Here satellites use different sensor packages to passively measure the reflectance from parts of the electromagnetic spectrum or radio waves that were sent out from an active sensor such as radar. Remote sensing collects raster data that can be further processed using different bands to identify objects and classes of interest, such as land cover. The most common method of data creation

2496-415: A specific aspect of the surface. Some of the most common include: Most of these are generated using algorithms that are discrete simplifications of vector calculus . Slope, aspect, and surface curvature in terrain analysis are all derived from neighborhood operations using elevation values of a cell's adjacent neighbours. Each of these is strongly affected by the level of detail in the terrain data, such as

2592-417: A successful mission completion. The most important parts of the survey are analysis and evaluation. The types of questions that archaeologist often ask of survey data include: what is the evidence for first occupation of an area; when was this area occupied; how are sites distributed; where are sites located; what evidence is there for a settlement hierarchy; what sites are contemporary with each other; how has

2688-459: A variety of application domains. Starting in the late 1970s, many software packages have been created specifically for GIS applications. Esri's ArcGIS , which includes ArcGIS Pro and the legacy software ArcMap , currently dominates the GIS market. Other examples of GIS include Autodesk and MapInfo Professional and open-source programs such as QGIS , GRASS GIS , MapGuide , and Hadoop-GIS . These and other desktop GIS applications include

2784-406: A variety of forms, such as a collection of separate data files or a single spatially-enabled relational database . Collecting and managing these data usually constitutes the bulk of the time and financial resources of a project, far more than other aspects such as analysis and mapping. GIS uses spatio-temporal ( space-time ) location as the key index variable for all other information. Just as

2880-420: A variety of tools when carrying out surveys, including GIS , GPS , remote sensing , geophysical survey and aerial photography . Survey work is conducted for a variety of reasons, some of which are motivated by threats to the preservation of archaeological material. These threats may include proposed land development or risks associated with processes such as decay or erosion. Surveys can also be conducted in

2976-415: A wide range of conditions. While common metal detectors are geophysical sensors, they are not capable of generating high-resolution imagery. Other established and emerging technologies are also finding use in archaeological applications. Although geophysical surveying has been used in the past with intermittent success, good results are very likely when it is applied appropriately. It is most useful when it

Banganarti - Misplaced Pages Continue

3072-438: Is digitization , where a hard copy map or survey plan is transferred into a digital medium through the use of a CAD program, and geo-referencing capabilities. With the wide availability of ortho-rectified imagery (from satellites, aircraft, Helikites and UAVs), heads-up digitizing is becoming the main avenue through which geographic data is extracted. Heads-up digitizing involves the tracing of geographic data directly on top of

3168-511: Is a GIS operation used to manipulate spatial data. A typical geoprocessing operation takes an input dataset , performs an operation on that dataset, and returns the result of the operation as an output dataset. Common geoprocessing operations include geographic feature overlay, feature selection and analysis, topology processing, raster processing, and data conversion. Geoprocessing allows for definition, management, and analysis of information used to form decisions. Many geographic tasks involve

3264-410: Is a building underneath a field. In such a case, the only way to decide if an excavation is worth the cost is to carefully analyze the evidence to determine which part to trust. On the one hand, the geophysics might just show an old and forgotten water-pipe, but it might also show the wall of just the building the archaeologists were looking for. The analysis therefore includes careful examination of all

3360-405: Is a good tool for planning a survey. Remains of older buildings often show in fields as cropmarks; just below the topsoil, the remains may affect the growth of crops or grass. There should preferably be photographs of the same area at different times of the year, allowing the analyst to find the best time to see cropmarks. If the indicator that started the process was not a record of previous work,

3456-653: Is a rapidly changing field, and GIS packages are increasingly including analytical tools as standard built-in facilities, as optional toolsets, as add-ins or 'analysts'. In many instances these are provided by the original software suppliers (commercial vendors or collaborative non commercial development teams), while in other cases facilities have been developed and are provided by third parties. Furthermore, many products offer software development kits (SDKs), programming languages and language support, scripting facilities and/or special interfaces for developing one's own analytical tools or variants. The increased availability has created

3552-433: Is a type of field research by which archaeologists (often landscape archaeologists ) search for archaeological sites and collect information about the location, distribution and organization of past human cultures across a large area (e.g. typically in excess of one hectare , and often in excess of many km ). Archaeologists conduct surveys to search for particular archaeological sites or kinds of sites, to detect patterns in

3648-508: Is becoming an increasingly useful and cost-effective tool in archaeology. Geophysical instruments can detect buried archaeological features when their electrical or magnetic properties contrast measurably with their surroundings. In some cases, individual artifacts, especially metal, may be detected as well. Readings taken in a systematic pattern become a dataset that can be rendered as image maps for interpretation. Survey results can be used to guide excavation and to give archaeologists insight into

3744-548: Is bore holes. Small holes are drilled into the ground, most often with hand-powered bores. The contents are examined to determine the depths at which one might find cultural layers, and where one might expect to strike virgin soil. This can be valuable in determining the cost of an excavation - if there is a build-up of several meters of soil above the layers the archaeologist is interested in, the price will obviously be much higher than if artifacts are found only centimeters below ground. One way to classify archaeological field surveys

3840-461: Is captured, the user should consider if the data should be captured with either a relative accuracy or absolute accuracy, since this could not only influence how information will be interpreted but also the cost of data capture. After entering data into a GIS, the data usually requires editing, to remove errors, or further processing. For vector data it must be made "topologically correct" before it can be used for some advanced analysis. For example, in

3936-464: Is collected and stored in various ways, the two data sources may not be entirely compatible. So a GIS must be able to convert geographic data from one structure to another. In so doing, the implicit assumptions behind different ontologies and classifications require analysis. Object ontologies have gained increasing prominence as a consequence of object-oriented programming and sustained work by Barry Smith and co-workers. Spatial ETL tools provide

Banganarti - Misplaced Pages Continue

4032-521: Is fairly good. A single researcher or team will walk slowly through the target area looking for artifacts or other archaeological indicators on the surface, often recording aspects of the environment at the time. The method works best on either ploughed ground or surfaces with little vegetation. On ploughed surfaces, as the soil is turned regularly artifacts will move to the top. Erosion and soil loss on uncultivated and lightly vegetated soil (e.g., in semi-arid environments) may cause artifacts to also 'rise' to

4128-437: Is far more precise than the machines of conventional map analysis. All geographical data are inherently inaccurate, and these inaccuracies will propagate through GIS operations in ways that are difficult to predict. Data restructuring can be performed by a GIS to convert data into different formats. For example, a GIS may be used to convert a satellite image map to a vector structure by generating lines around all cells with

4224-420: Is more commonly used, heads-down digitizing is still useful for digitizing maps of poor quality. Existing data printed on paper or PET film maps can be digitized or scanned to produce digital data. A digitizer produces vector data as an operator traces points, lines, and polygon boundaries from a map. Scanning a map results in raster data that could be further processed to produce vector data. When data

4320-445: Is no single standard for data quality, because the necessary degree of quality depends on the scale and purpose of the tasks for which it is to be used. Several elements of data quality are important to GIS data: The quality of a dataset is very dependent upon its sources, and the methods used to create it. Land surveyors have been able to provide a high level of positional accuracy utilizing high-end GPS equipment, but GPS locations on

4416-449: Is prohibitively high. The various Scandinavian sites and monuments registers mainly list above-ground monuments, not ploughed-out sites with scattered pottery. Because of the high costs involved in some kinds of surveys, it is often helpful to use " predictive modelling " to narrow down the search for archaeological materials. This is particularly important for purposive surveys, but can also be used to guide sampling surveys by eliminating

4512-521: Is the proliferation of geospatial libraries and application programming interfaces (e.g., GDAL , Leaflet , D3.js ) that extend programming languages to enable the incorporation of GIS data and processing into custom software, including web mapping sites and location-based services in smartphones . The core of any GIS is a database that contains representations of geographic phenomena, modeling their geometry (location and shape) and their properties or attributes . A GIS database may be stored in

4608-498: Is the theoretical width of a transect in which the number of artifacts detected outside the sweep is identical to the number missed within the sweep. The poorer the visibility, the poorer the contrast between the artifact "targets" and their surroundings, or the poorer the surveyor's skill or attention, the narrower the sweep width will be. Modern technology such as GPS has made survey recording much easier, as positions of artifacts or artifact clusters ("sites") can be taken well within

4704-524: Is to divide them into two types: intensive and extensive . The former is characterised by the complete or near-complete coverage of the survey area at a high resolution, most often by having teams of survey archaeologists walk in a systematic way (e.g. in parallel transects ) over parcels of the landscape in question, documenting archaeological data such as lithics , ceramics and/or building remains. However, variations in artifact visibility related to topography, vegetation, and soil character, not to mention

4800-498: Is to utilize applications available on smartphones and PDAs in the form of mobile GIS. This has been enhanced by the availability of low-cost mapping-grade GPS units with decimeter accuracy in real time. This eliminates the need to post process, import, and update the data in the office after fieldwork has been collected. This includes the ability to incorporate positions collected using a laser rangefinder . New technologies also allow users to create maps as well as analysis directly in

4896-467: Is used in a well-integrated research design where interpretations can be tested and refined. Interpretation requires a knowledge both of the archaeological record , and of the way it is expressed geophysically. Appropriate instrumentation, field survey design, and data processing are essential for success, and must be adapted to the unique geology and archaeological record of each site. In the field, control of data quality and spatial accuracy are critical to

SECTION 50

#1732771914818

4992-640: The CAD  platform, Environmental Systems Research Institute ( ESRI ), CARIS  (Computer Aided Resource Information System), and ERDAS (Earth Resource Data Analysis System) emerged as commercial vendors of GIS software, successfully incorporating many of the CGIS ;features, combining the first-generation approach to separation of spatial and attribute information with a second-generation approach to organizing attribute data into database structures. In 1986, Mapping Display and Analysis System (MIDAS),

5088-426: The Internet , requiring data format and transfer standards. More recently, a growing number of free, open-source GIS packages run on a range of operating systems and can be customized to perform specific tasks. The major trend of the 21st Century has been the integration of GIS capabilities with other Information technology and Internet infrastructure, such as relational databases , cloud computing , software as

5184-400: The terrain , the shape of the surface of the earth, such as hydrology , earthworks , and biogeography . Thus, terrain data is often a core dataset in a GIS, usually in the form of a raster Digital elevation model (DEM) or a Triangulated irregular network (TIN). A variety of tools are available in most GIS software for analyzing terrain, often by creating derivative datasets that represent

5280-548: The Earth's surface. The simplest model is to assume the earth is a perfect sphere. As more measurements of the earth have accumulated, the models of the earth have become more sophisticated and more accurate. In fact, there are models called datums that apply to different areas of the earth to provide increased accuracy, like North American Datum of 1983 for U.S. measurements, and the World Geodetic System for worldwide measurements. The latitude and longitude on

5376-742: The Institute of Mediterranean and Oriental Cultures of the Polish Academy of Sciences , and (since 2016) the Institute of Archaeology, University of Rzeszów . It conducts archaeological excavations and conservation and reconstruction works in cooperation with the Sudanese National Corporation for Antiquities and Museums (NCAM).   In the first seasons, the work focused on the large church in Banganarti. It consists of two successive buildings, dating respectively to

5472-610: The Lower Church as well. The Upper Church functioned from the mid-eleventh to the mid-eighteenth century. It was a pilgrim center, as attested by almost 1,000 inscriptions left by visitors on the walls of the Raphaelion. They are written in Greek , Old Nubian , or a mixture of both. They mention a few Nubian kings and other prominent persons, such as a queen mother, which gives them historical importance. Wall paintings are among

5568-444: The absence of threat as part of a research program or conservation efforts. Prior to engaging in fieldwork, desk-based assessments will likely take place, during which, written, visual, and electronic information is gathered for the purpose of evaluating and developing a plan for future fieldwork. Consideration should be given to the nature of the landscape (vegetation coverage, existing settlement or industry, soil depth, climate) before

5664-517: The aerial imagery instead of by the traditional method of tracing the geographic form on a separate digitizing tablet (heads-down digitizing). Heads-down digitizing, or manual digitizing, uses a special magnetic pen, or stylus, that feeds information into a computer to create an identical, digital map. Some tablets use a mouse-like tool, called a puck, instead of a stylus. The puck has a small window with cross-hairs which allows for greater precision and pinpointing map features. Though heads-up digitizing

5760-410: The archaeologists will need to check if any work has been done prior to commencement of the pending project. As many older surveys and excavations were published in papers that are not widely available, this may be a difficult task. A common way to handle this is through a visit to the area, to check with local museums, historians and older people who might remember something about the former activities in

5856-439: The average smartphone are much less accurate. Common datasets such as digital terrain and aerial imagery are available in a wide variety of levels of quality, especially spatial precision. Paper maps, which have been digitized for many years as a data source, can also be of widely varying quality. A quantitative analysis of maps brings accuracy issues into focus. The electronic and other equipment used to make measurements for GIS

SECTION 60

#1732771914818

5952-455: The data processing functionality of traditional extract, transform, load  (ETL) software, but with a primary focus on the ability to manage spatial data. They provide GIS users with the ability to translate data between different standards and proprietary formats, whilst geometrically transforming the data en route. These tools can come in the form of add-ins to existing wider-purpose software such as spreadsheets . GIS spatial analysis

6048-429: The datum is the ' North American Datum of 1983' is denoted by 'GCS North American 1983'. While no digital model can be a perfect representation of the real world, it is important that GIS data be of a high quality. In keeping with the principle of homomorphism , the data must be close enough to reality so that the results of GIS procedures correctly correspond to the results of real world processes. This means that there

6144-464: The distribution of material culture over regions, to make generalizations or test hypotheses about past cultures, and to assess the risks that development projects will have adverse impacts on archaeological heritage. Archaeological surveys may be: (a) intrusive or non-intrusive , depending on the needs of the survey team (and the risk of destroying archaeological evidence if intrusive methods are used) and; (b) extensive or intensive , depending on

6240-752: The early 1960s. In 1963, the world's first true operational GIS was developed in Ottawa, Ontario , Canada, by the federal Department of Forestry and Rural Development. Developed by Roger Tomlinson , it was called the Canada Geographic Information System (CGIS) and was used to store, analyze, and manipulate data collected for the Canada Land Inventory , an effort to determine the land capability for rural Canada by mapping information about soils , agriculture, recreation, wildlife, waterfowl , forestry and land use at

6336-489: The early days of GIS: Ian McHarg 's publication Design with Nature and its map overlay method and the introduction of a street network into the U.S. Census Bureau's DIME ( Dual Independent Map Encoding ) system. The first publication detailing the use of computers to facilitate cartography was written by Waldo Tobler in 1959. Further computer hardware development spurred by nuclear weapon research led to more widespread general-purpose computer "mapping" applications by

6432-652: The evidence collected. A method often used to determine its value is to compare it to sites of the same period. As the number of well-documented surveys grow, this becomes a slightly easier task, as it is sometimes easier to compare two survey results than to compare a survey result with an excavated site. However, it remains difficult to compare datasets produced by different research teams. Geographic information system A geographic information system ( GIS ) consists of integrated computer hardware and software that store, manage, analyze , edit, output, and visualize geographic data . Much of this often happens within

6528-527: The field, making projects more efficient and mapping more accurate. Remotely sensed data also plays an important role in data collection and consist of sensors attached to a platform. Sensors include cameras, digital scanners and lidar , while platforms usually consist of aircraft and satellites . In England in the mid-1990s, hybrid kite/balloons called helikites first pioneered the use of compact airborne digital cameras as airborne geo-information systems. Aircraft measurement software, accurate to 0.4 mm,

6624-597: The first desktop GIS product, was released for the DOS operating system. This was renamed in 1990 to MapInfo for Windows when it was ported to the Microsoft Windows platform. This began the process of moving GIS from the research department into the business environment. By the end of the 20th century, the rapid growth in various systems had been consolidated and standardized on relatively few platforms and users were beginning to explore viewing GIS data over

6720-408: The first examples of general-purpose GIS software that was not developed for a particular installation, and was very influential on future commercial software, such as Esri ARC/INFO , released in 1983. By the late 1970s two public domain GIS systems ( MOSS and GRASS GIS ) were in development, and by the early 1980s, M&S Computing (later Intergraph ) along with Bentley Systems Incorporated for

6816-587: The foundation of location-enabled services, which rely on geographic analysis and visualization. GIS provides the ability to relate previously unrelated information, through the use of location as the "key index variable". Locations and extents that are found in the Earth's spacetime are able to be recorded through the date and time of occurrence, along with x, y, and z coordinates ; representing, longitude ( x ), latitude ( y ), and elevation ( z ). All Earth-based, spatial–temporal, location and extent references should be relatable to one another, and ultimately, to

6912-661: The identification of archaeological sites across a large area, whereas intensive surveys are designed to provide a more comprehensive picture of the location of sites and the nature of off-site data (e.g. field systems , isolated finds, etc.). An intensive survey is the more costly, timely, and ultimately informative of the two approaches, although extensive surveys can provide important information about previously unknown areas. Archaeological field surveys can also be characterized as either purposive or sampling surveys. The former, sometimes also called " archaeological prospection ", involves cases where archaeologists are searching for

7008-454: The imperfect detection abilities of human observers, bring into question the very concept of complete coverage. An extensive survey , on the other hand, is characterised by a low-resolution approach over targets within a study area (sometimes including hundreds of km²). Sometimes this involves a random sampling or some other kind of probability sample to gain a representative sample of the study area. Extensive surveys may be designed to target

7104-747: The industry and profession concerned with these systems. It is roughly synonymous with geoinformatics . The academic discipline that studies these systems and their underlying geographic principles, may also be abbreviated as GIS, but the unambiguous GIScience is more common. GIScience is often considered a subdiscipline of geography within the branch of technical geography . Geographic information systems are utilized in multiple technologies, processes, techniques and methods. They are attached to various operations and numerous applications, that relate to: engineering, planning, management, transport/logistics, insurance, telecommunications, and business. For this reason, GIS and location intelligence applications are at

7200-484: The layers were finished, they were combined into one image using a large process camera. Once color printing came in, the layers idea was also used for creating separate printing plates for each color. While the use of layers much later became one of the typical features of a contemporary GIS, the photographic process just described is not considered a GIS in itself – as the maps were just images with no database to link them to. Two additional developments are notable in

7296-426: The limits of accuracy and precision necessary for survey work. Recording the position and attributes of archaeological features has been expedited by customizable portable computing interfaces or mobile Geographical Information Systems ( GIS ). Databases containing existing regional archaeological data as well as other landscape GIS layers such as soils, vegetation, modern features, and development plans can be loaded on

7392-448: The modern landscape interfered with the visibility of archaeological remains; what sorts of activities can be recognized (e.g., dwellings, tombs, field systems); how many people lived in this area at any given time or how did population density change over time; why did people choose to live where they did; how has the landscape changed over time; what changes in settlement patterns have there been? However, answering such questions depends on

7488-484: The most important discoveries made in Banganarti. Fifteen were uncovered on the walls of the Lower Church, but they were in much worse condition than the ones decorating the interior of Raphaelion II. The iconographical program of the Upper Church is undoubtedly rooted in political theology and royal propaganda. Of the 57 preserved wall paintings, 13 were hieratic depictions of a king. Large figurative scenes showing

7584-442: The need to survey areas where, for geological or other reasons, we can reasonably expect all ancient traces to be destroyed (e.g., by erosion) or far too deeply buried (e.g., by alluvium) to be detectable. Modern predictive models in archaeology employ Geographic Information Systems (GIS). A geophysical survey is used for subsurface mapping of archaeological sites. In recent years, there have been great advances in this field, and it

7680-653: The patterning of non-excavated parts of the site. Unlike other archaeological methods, geophysical survey is not invasive or destructive. For this reason, it is often used where preservation (rather than excavation) is the goal for project preservation and compliance with applicable laws. The geophysical methods most commonly applied to archaeology are magnetometers , electrical resistance meters, ground-penetrating radar (GPR) and electromagnetic (EM) conductivity. These methods provide excellent resolution of many types of archaeological features, and are capable of high sample density surveys of very large areas and of operating under

7776-507: The plateau and upper scarp or valley side soils will move down slope, forming a deep seal over low-lying archaeological deposits, rendering them inaccessible to surface survey. Even artifacts on the surface and with relatively high visibility (i.e., little obscuring vegetation), however, are not consistently detected by surveyors. Consequently, it is unrealistic to expect 100% recovery of artifacts or even sites. We can evaluate surveyors' effectiveness at detecting artifacts with "Sweep width," which

7872-443: The potential archaeological significance of places where development is proposed. This is usually connected to construction work and road building. The assessment determines whether the area of development impact is likely to contain significant archaeological resources and makes recommendations as to whether the archaeological remains can be avoided or an excavation is necessary before development work can commence. Archaeologists use

7968-449: The property owner. In a non-intrusive survey, nothing is touched, just recorded. An accurate survey of the earthworks and other features can enable them to be interpreted without the need for excavation . An intrusive survey can mean different things. In some cases, all artifacts of archaeological value are collected. This is often the case if it is a rescue survey, but less common in a regular survey. Another form of intrusive research

8064-402: The quality of the evidence, which is why it is important to evaluate the effectiveness and thoroughness of the survey or surveys that contribute that evidence. At times, one part of the survey may not have yielded the evidence one wanted to find. For instance, very little may have been found during a field walk, but there are strong indications from geophysical survey and local stories that there

8160-663: The real world, such as roads, land use, elevation, trees, waterways, and states. The most common types of phenomena that are represented in data can be divided into two conceptualizations: discrete objects (e.g., a house, a road) and continuous fields (e.g., rainfall amount or population density). Other types of geographic phenomena, such as events (e.g., location of World War II battles), processes (e.g., extent of suburbanization ), and masses (e.g., types of soil in an area) are represented less commonly or indirectly, or are modeled in analysis procedures rather than data. Traditionally, there are two broad methods used to store data in

8256-414: The same classification, while determining the cell spatial relationships, such as adjacency or inclusion. More advanced data processing can occur with image processing , a technique developed in the late 1960s by NASA and the private sector to provide contrast enhancement, false color rendering and a variety of other techniques including use of two dimensional Fourier transforms . Since digital data

8352-622: The same data, see map projections ), but all Earth-based spatial–temporal location and extent references should, ideally, be relatable to one another and ultimately to a "real" physical location or extent in space–time. Related by accurate spatial information, an incredible variety of real-world and projected past or future data can be analyzed, interpreted and represented. This key characteristic of GIS has begun to open new avenues of scientific inquiry into behaviors and patterns of real-world information that previously had not been systematically correlated . GIS data represents phenomena that exist in

8448-461: The seventh and the eleventh century. Several burials were discovered inside. Both buildings were decorated with high-quality wall paintings. One of the oldest images of the Virgin Mary has been found in the Lower Church. The younger building, the Upper Church, is called Raphaelion II after its patron, Archangel Raphael . The number ‘II’ was added because Raphael had probably been the patron of

8544-403: The surface. Even with optimal surface conditions the efficacy of fieldwalking varies according to long-term land use, topography, weather conditions, the skill and experience of the fieldwalkers, and other factors. Intensive arable agriculture on hilltops will first expose and then pulverize artifacts such as pottery and even chipped stone (typically flint, chert or obsidian) flakes. Conversely,

8640-401: The types of research questions being asked of the landscape in question. Surveys can be a practical way to decide whether or not to carry out an excavation (as a way of recording the basic details of a possible site), but may also be ends in themselves, as they produce important information about past human activities in a regional context. A common role of a field survey is in assessment of

8736-513: The vegetation and landscape to decide what may be hidden under the vegetation, or survey by subsurface testing (SST). SSTs can consist of a series of shovel-test pits that penetrate the humus layer or turf or, where substantial later sediments may cover archaeological materials, series of auger or core holes. SSTs are much more costly than fieldwalking, and surveys by SST usually have very low probability of intersecting and detecting archaeological remains unless intensity (density of SSTs), and thus cost,

8832-460: Was able to determine the source of a cholera outbreak in London through the use of spatial analysis. Snow achieved this through plotting the residence of each casualty on a map of the area, as well as the nearby water sources. Once these points were marked, he was able to identify the water source within the cluster that was responsible for the outbreak. This was one of the earliest successful uses of

8928-608: Was never available commercially. In 1964, Howard T. Fisher formed the Laboratory for Computer Graphics and Spatial Analysis at the Harvard Graduate School of Design (LCGSA 1965–1991), where a number of important theoretical concepts in spatial data handling were developed, and which by the 1970s had distributed seminal software code and systems, such as SYMAP, GRID, and ODYSSEY, to universities, research centers and corporations worldwide. These programs were

9024-411: Was particularly used for printing contours – drawing these was a labour-intensive task but having them on a separate layer meant they could be worked on without the other layers to confuse the draughtsman . This work was initially drawn on glass plates, but later plastic film was introduced, with the advantages of being lighter, using less storage space and being less brittle, among others. When all

9120-599: Was used came from the field of epidemiology in the Rapport sur la marche et les effets du choléra dans Paris et le département de la Seine (1832). French cartographer and geographer Charles Picquet created a map outlining the forty-eight districts in Paris , using halftone color gradients, to provide a visual representation for the number of reported deaths due to cholera per every 1,000 inhabitants. In 1854, John Snow , an epidemiologist and physician,

9216-460: Was used to link the photographs and measure the ground. Helikites are inexpensive and gather more accurate data than aircraft. Helikites can be used over roads, railways and towns where unmanned aerial vehicles (UAVs) are banned. Recently aerial data collection has become more accessible with miniature UAVs and drones. For example, the Aeryon Scout was used to map a 50-acre area with

#817182