Laser DEM Grids consists of 27 digital elevation model grids. The Arcview grid files were constructed from the Airborne Laser Scanning shapefiles. The Laser DEM grid tiles cover the eastern portion of the Christmas Island. Each grid contains the height in metres of the ground surface with a value every one metre on the ground.

Product no longer exists, please refer to GeoCat #30413 for the data

Product no longer exists, please refer to GeoCat #30413 for the data

A useful spin off of the soft photogrammetry is the opportunity to get one metre contours over the disturbed areas of the Island. For the north-east area of the Island 2km X 2km DEM contour tiles have been trialed in the CIGIS. Most are at a contour interval of 5 metres but tiles 2269 and 2469 have been done at a one metre contour interval. The DEM contours are surface contours. They pick up the reflective surface beneath the aircraft. The reflective surface may be the ground or it may be a dense vegetation canopy or rooftops etc. Further one metre contour coverage can be prepared on a cost recovered basis.

Lord Howe Island is a small, mid-ocean volcanic and carbonate island in the southwestern Pacific Ocean. Skeletal carbonate eolianite and beach calcarenite on the island are divisible into two formations based on lithostratigraphy. The Searles Point Formation comprises eolianite units bounded by clay-rich paleosols. Pore-filling sparite and microsparite are the dominant cements in these eolianite units, and recrystallised grains are common. Outcrops exhibit karst features such as dolines, caves and subaerially exposed relict speleothems. The Neds Beach Formation overlies the Searles Point Formation and consists of dune and beach units bounded by weakly developed fossil soil horizons. These younger deposits are characterised by grain-contact and meniscus cements, with patchy pore-filling micrite and mirosparite. The calcarenite comprises several disparate successions that contain a record of up to 7 discrete phases of deposition. A chronology is constructed based on U/Th ages of speleothems and corals, TL ages of dune and paleosols, AMS 14C and amino acid racemization (AAR) dating of land snails and AAR whole-rock dating of eolianite. These data indicate dune units and paleosols of the Searles Point Formation were emplaced during oxygen isotope stage (OIS) 7 and earlier in the Middle Pleistocene. Beach units of the Neds Beach Formation were deposited during OIS 5e while dune units were deposited during two major phases, the first coeval with or shortly after the beach units, the second later during OIS 5 (e.g. OIS 5a) when the older dune and beach units were buried. Large-scale exposures and morphostratigraphical features indicate much of the carbonate was emplaced as transverse and climbing dunes, with the sediment source located seaward of and several metres below the present shoreline. The lateral extent and thickness of the eolianite deposits contrast markedly with the relatively small modern dunes.

This document describes a format of the AVNIR-2 (Advanced Bisible Near-Infrared Radiometer) products generaged by the ALOS Data Processing Subsystem.

This dataset maps the geomorphic habitat environments (facies) for 36 South Australian coastal waterways. The classification system contains 12 easily identifiable and representative environments: Barrier/back-barrier, Bedrock, Central Basin, Channel, Coral, Flood- and Ebb-tide Delta, Fluvial (bay-head) Delta, Intertidal Flats, Mangrove, Rocky Reef, Saltmarsh/Saltflat, Tidal Sand Banks (and Unassigned). These types represent habitats found across all coastal systems in Australia. Most of the 36 coastal waterways have a "Modified" environmental condition (as opposed to "Near Pristine"), according to the National Land and Water Resources Audit definition.

Exploration fundamentals related to predicted world economic growth and higher oil prices suggest a resurgence in exploration for oil and gas liquids in the Timor Sea in the next two years, despite a slow down in exploration drilling in the last 12 months.

The Valley Networks dataset covers the whole of Christmas Island. It contains low elevation lines that were constructed from the 25K Digital elevation map. The lines were obtained by running a series of ArcView grid commands using the Hydrologic Modeling v1.1 extention. The valley_net.shp contains the following fields: Field Type Precision Decimal---------------------------------------------------Shape FIELD_SHAPELINE 0 9Id FIELD_DECIMAL 0 11Gridcode FIELD_DECIMAL 0 10Length FIELD_DECIMAL 3 16

This dataset has been digitised from the 1:25000 vegetation map of Christmas Island (accompanying Mitchells 1985 report). The vector version was completed on behalf of Parks Australia Christmas Island. Geoscience Australia used ArcInfo to heads-up digitise a scanned version of the map. Once digitised the arcs were built into polygons and the map was attributed based on the Geoscience Australia data dictionary guidelines. All information relating to vegetation boundaries was extracted from the map and incorporated in the table. The fields that were used follow: Alias Type Width Decimal -----------------------------------------------Shape FIELD_SHAPEPOLY 80Ufi FIELD_DECIMAL 6 0 - unique numberArea FIELD_DECIMAL 18 5Perimeter FIELD_DECIMAL 18 5Code FIELD_CHAR 80 0 - Vegetation unit (map symbol)Descript FIELD_CHAR 64 0 - Description of unitCategories FIELD_CHAR 50 0 - vegetation categoriesFeature FIELD_CHAR 12 0 - (GA field)Plotrank FIELD_DECIMAL 1 0 - (GA field)