Generalized Geology of Southeast Asia (geo3bl)

Resource lineage description

source

source description  Source Contribution: outlines and attributes of geologic age and typeSource Type paper

representative resolution scale:

Scale denominator: 5000000

source citation

Title Geology of East and South Asia, sheets 3 and 4

publication  Date   1990-00-00

Edition Third

presentationForm  mapDigital

cited responsible party - publisher

organisation Name  UNESCO

Contact information

Address

, Paris, France

cited responsible party - originator

organisation Name  United Nations Educational, Scientific and Cultural Organization (UNESCO)/ Committee for Geologic Map of the World (CMGW)(ed.)

source

source description  Source Contribution: outlines and attributes of geologic age and typeSource Type paper

representative resolution scale:

Scale denominator: 5000000

source citation

Title Geological Map of the World: Australia and Oceania

publication  Date   1965-00-00

cited responsible party - publisher

organisation Name  Bureau of Mineral Resources, Geology and Geophysics, Australia Department of National Development (now Australian Geological Survey Organisation)

Contact information

Address

, Canberra, Australia

cited responsible party - originator

organisation Name  Bureau of Mineral Resources, Geology and Geophysics, Australia Department of National Development (now Australian Geological Survey Organisation)

source

source description  Source Contribution: Used as a guide to match coastlines and inland water bodies, and to verify island locationsSource Type CD-ROM

representative resolution scale:

Scale denominator: 3000000

source citation

Title Arcworld cntry_92

publication  Date   1992-00-00

cited responsible party - publisher

organisation Name  Environmental Systems Research Institute, Inc. (ESRI)

Contact information

Address

, Redlands, CA, U.S.A.

cited responsible party - originator

organisation Name  Environmental Systems Research Institute, Inc. (ESRI)(comp.)

cited responsible party - originator

organisation Name  Environmental Systems Research Institute, Inc. (ESRI)(comp.)

AbsoluteExternalPositionalAccuracy

name Of Measure Horizontal Positional Accuracy Report

evaluation Method Description  There are difficulties registering the scanned gray-scale images of the original UNESCO source maps. The latitude and longitude graticules do not match the stated map projection at the corners of the maps beyond the area mapped geologically. In particular, the upper left corner of map sheet 1, the extreme Northwest portion, and the upper right corner of map sheet 2, the extreme Northeast portion, have latitude and longitude graticules that deviate from a calculated graticule using the Arc/Info generate and project commands. Coastlines and inland water bodies abstracted from ESRI Arcworld 1:3m countries and rivers are used to rectify the images. Because international boundaries were not depicted on the UNESCO source maps, it is not possible to use borders to rectify the images. Although a relatively low RMS error is achieved in registering the images, there is little control in the Northwest portion of the coverage. The registration is inconsistent across the four map sheets used to compile this coverage. When the coverage is digitized, there remain discrepencies with the ESRI sourced coverage. (ESRI Arcworld is chosen as a standard because it is widely accepted and available.) These discrepencies are in part the result of the registration problem, and in part caused by compilation differences between UNESCO and ESRI. Using a roving window, piecewise rubbersheeting is performed with the Arc/Info adjust command, polygon option. Identifiable features of inland water bodies and shorelines common to both sources are used as targets to create the "to - from" links for adjusting the coverage. The portions of this coverage depicting New Guinea and the Solomon Islands, and parts of Australia are compiled from the AGSO source map and do not experience the same degree of registration problems. The latitude and longitude graticule agree closely with the calculated graticule. No rubbersheetingis perfomed on these portions. Overlaying plots of this coverage, corresponding to the source maps in scale, projection and map extent, on a light table shows a variable offset ranging from 0 to 5 mm (25 km). The following describe the tolerances of the section compiled from the UNESCO maps: 1. Original geologic maps are presumed to be of 500 meter maximum accuracy (0.1mm at 5,000,000 scale) 2. Scanned gray-scale images are of 200 dot/inch resolution (0.13 mm on paper map) 3. Scanned images are registered and rectified with an average RMS error of 641 meters. (0.1 mm on paper map) 4. Fuzzy tolerance is set at 500 meters (0.71 pixel) and weed tolerance is set at 250 meters (0.31 pixel) 5. 100 points are sampled on the master coverage for fit with ESRI Arcworld country boundaries and an RMS error is calculated of 780 meters, the maximum error was 11,400 meters. The following describe the tolerances of the section compiled from the AGSO map: 1. Original geologic maps are of 500 meter maximum accuracy (0.1mm at 5,000,000 scale) 2. Scanned gray-scale images are of 200 dot/inch resolution (0.13 mm on paper map) 3. Scanned images are registered and rectified with an average RMS error of 270 meters. (0.05 mm on paper map) 4. Fuzzy tolerance is set at 500 meters (0.71 pixel) and weed tolerance is set at 250 meters (0.31 pixel)

Completeness Commission

evaluation Method Description  An informal threshold of 1500 meters of width or length is used in digitizing features from the source maps. This threshold is not uniformly applied. Geologic ages indicated on the source maps as uncertain or questionable are attributed without comment. Ages that are divided on the original maps are attributed as undivided. For example: two adjacent polygons of Lower and Middle Cretaceous age are digitized and attributed as one polygon of Cretaceous age. Some unusual age classifications are attributed in a more generalized or standard manner. For instance: Upper Permian through Tertiary is attributed as Cenozoic/Mesozoic, Carboniferous through Triassic is attributed as Mesozoic/Paleozoic, and Upper Triassic through Lower Cretaceous as Mesozoic. Acid, Intermediate and Basic igneous rocks are not differentiated and are attributed as either intrusive or extrusive igneous rocks. Areas indicated on the map as either Ultrabasic or Ophiolitic are classed together as Ultrabasic or Ophiolite.

Completeness Omission

evaluation Method Description  An informal threshold of 1500 meters of width or length is used in digitizing features from the source maps. This threshold is not uniformly applied. Geologic ages indicated on the source maps as uncertain or questionable are attributed without comment. Ages that are divided on the original maps are attributed as undivided. For example: two adjacent polygons of Lower and Middle Cretaceous age are digitized and attributed as one polygon of Cretaceous age. Some unusual age classifications are attributed in a more generalized or standard manner. For instance: Upper Permian through Tertiary is attributed as Cenozoic/Mesozoic, Carboniferous through Triassic is attributed as Mesozoic/Paleozoic, and Upper Triassic through Lower Cretaceous as Mesozoic. Acid, Intermediate and Basic igneous rocks are not differentiated and are attributed as either intrusive or extrusive igneous rocks. Areas indicated on the map as either Ultrabasic or Ophiolitic are classed together as Ultrabasic or Ophiolite.

ConceptualConsistency

measure Description  Polygon topology. Each polygon has one unique label point with unique id, there are no dangles. Polygons are bounded at perimeter of extent, including areas attributed as water and where geologic age is not shown. The coverage has been topologically cleaned and built in Arc/Info 7.1.2.