Christmas Island lies about 1600 km north-north west of Australia's Northwest Cape and approximately 350 km south of Java in the northern part of the Wharton basin (IndianOcean). Recently Australia declared a 200 mile Fisheries Zone around the island andAGSO was asked to assess seabed morphology, sediment thickness and offshore mineralresources in this area. In February 1992 RAT "Rig Seismic" carried out a detailed survey ofthe region, providing relevant data for the required assessment. Eight seismic profiles wereacquired on this cruise, totalling about 2000 km, and almost twice as much bathymetricdata was recorded. In conjunction with seismic and bathymetic data collected by otherinstitutions, our data provides a good coverage of the area, which enabled us to compile anew bathymetric map and to produce the first sediment thickness map. Among the published bathymetric maps only three cover the Christmas Island area: 1)published by Udintsev (Geophysical Atlas of the Indian Ocean, 1975; 1:5,000 000), 2) byMammerickx et al. (1976, 1:5,000 000) and 3) 1:10,000 000 General BathymetricCompilation (GEBCO) map, published by the International Oceanographic Service (1982).All published bathymetric maps were compiled in the end of the 1970s and the beginningof the 1980s, and all of them were based on processing analog records of water depths andwere drafted manually. Moreover, most of the data for map compilation were collectedusing a sextant, and only a very limited using satellite navigation. The amount and quality of data collected by the end of the 1970s allowed the production ofthe fairly accurate 1:5,000 000 and 1:10,000 000 maps of the Indian Ocean listed above,however a lot of smaller features, such as individual seamounts, are missing on those maps.Insufficient data coverage led to broad extrapolation of bathymetric trends, sometimesderived purely from magnetic lineation pattern (Fig.1). To the east of Christmas Island thelack of information is particularly evident: all the maps differ in their interpretation of this area. New high quality data collected by "Rig Seismic", and digital water depths obtained fromthe USA National Geophysical Data Bank (NGDC), were used for compilation of a newrevised version of the bathymetric map on the Christmas Island area in a 1:1,000 000 scale.The new map (to be published in AGSO's Offshore Resources Map Series) contains a lotmore detail on the complex bathymetry of the area, and gives a more realistic picture ofseamount distribution and the structure of the Java Trench and Java's outer-arc ridge. Theamount of added information can be clearly deduced from comparison of Fig.1 and Fig.2.The time scale used in this report is that of McDougall (1974) and Fanoon et al. (1993).

Laser DEM Shiny Colour Drape Images contains Digital Elevation Model (DEM) tiles covering the eastern half of Christmas Island as 8 bit TIFF, 24 bit TIFF, and ECW images. A LiDAR Digital Elevation Model (DEM) was constructed for the eastern half of Christmas Island from ground heights obtained from an airborne laser scanning survey flown September 2000 by AAM Surveys Pty Ltd. Shiny colour drape images of the ground surface were produced from this DEM in Geoscience Australia by processing the set of last returns (mostly ground heights), and the GPS location in MGA (GDA94) units of each height. Point shape files and Arc grids were also created from the raw data by GA. 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.

The Christmas Island Geographic Information System (CIGIS) is a collection of spatial data, viewing and analysis tools dealing with Christmas Island, Indian Ocean. The data include orthophotography, topographic, mining, cultural and environmental features of the island. This work is part of ongoing service to the Department of Transport and Regional Services.

A contoured (interval 10m) general reference map of the island showing settlement, mining areas, railways, roads and tracks of Christmas Island.

A 1:10,000 scale general reference and tourist map of the island showing settlement, mining areas, railways, roads and tracks, and the boundary of Christmas Island National Park

Printed Orthophoto map.

Printed Orthophoto map.

Christmas Island is located approximately 2,600 North West of Perth. It is the surface expression of an emergent seamount uplifted by tectonics. Bathymetry data are required in this area to help identify major seabed processes and habitats. The data are also required to enable modelling of tsunami as they interact with the shelf around the island and the coast. This report describes the methodology employed in creating detailed bathymetry data grids of the Christmas Island region. It covers data collection, quality control and gridding. Descriptions are provided of each dataset employed, the methods used to integrate the different datasets and the attributes of the new bathymetric models. Five new bathymetry grids are presented, including grids that integrate bathymetry with the island's topography.<p><p>This dataset is not to be used for navigational purposes.

This map shows the boundary of the security regulated port for the purpose of the Maritime Transport & Office Security Act 2003. 5 Sheets (Colour) May 2010 Not for sale or public distribution Contact Manager LOSAMBA project, PMD

Christmas Island is an Australian territory lying south of Java inthe Indian Ocean, at about 10°30'S and 105°40'E. It lies on oceanic crust of Late Cretaceous age, is moving north at 7cm/year, andis being raised as it climbs the bulge on the southern flank of the Java Trench. The island itself consists of Cainozoic volcanics and limestone, and has been extensively mined for Pliocene phosphate. It covers an area of 140 km2 , and rises 360 m above sea level. Australia has declared a 200 mile Fisheries Zone around the island, and the aim of this BMR investigation is to assess the seabed morphology, sediment thickness, and offshore mineral resources in a future Exclusive Economic Zone. This information will be of particular value to the Department of Foreign Affairs and Trade, when Australia negotiates a Christmas Island seabed boundary with Indonesia to the north. Present knowledge indicates that oceanic crust is generally at 5000-6000 m around Christmas Island, and that it is overlain by 100-300m of pelagic sediment which thickens northward toward the Java Trench. A number of volcanic ridges trend generally northeast or north-northeast, and are as shallow as 1200 m below sea level. Christmas Island itself sits on such a ridge. Shallow-water limestones and manganese oxide crusts have been dredged from the ridges. Deepseacoring programs show that pelagic foraminiferal ooze and marl give way to siliceous (diatom-radiolarian) ooze and red clay below 5000 in water depth. Volcanic ash from Indonesia is an additional component of the sediment. Reconnaissance sampling has shown that manganese nodules are quite common in the deep sea, and that they carry moderate grades of the valuable metals, copper (Cu), nickel (Ni) and cobalt (Co). In a fairly similar geological setting to the west, in the central Indian Ocean, India has pioneer investor status for a nodule mine site of 150,000 square kilometres. At this site the grade of Cu+Ni+Co is about 2.55%,and nodule abundance is 5-7.5% of wet nodules per square metre, figures which suggest that the site has long-term economic potential. The present project will commence with a 28-day geoscience cruise of R.V. "Rig Seismic" from 7 January to 4 February, 1992. The plan isto acquire about 2500 km of high-resolution reflection seismic and bathymetric data, to define seabed morphology and to allow regional mapping of sediment thickness and facies. The seismic data will beused as the basis of a sampling campaign to investigate sediment type, manganese nodule abundance and metal grade on the deepsea floor, and manganese crust thickness and metal grade on the volcanic ridges. The end result will be a comprehensive review of the geology and mineral resources of the Christmas Island offshore zone.