Geosoft - Exploring With Data

New Data: Magnetic anomaly grids of Western Australia

We have just added statewide geophysical compilations of magnetic anomaly grids of Western Australia including Magnetic anomaly grids (80 m, 40 m, 20 m) of Western Australia.

The largest of these grids has a cell size of ~ 20 metres (0.00020823 degrees). The grid file is approximately 30 GB! Save time by using Seeker to download just the area you need in the coordinate system that you are already using, or browse the imagery on the Geoscience Data Service.

Learn more about these datasets at the Government of Western Australia website: Magnetic anomaly grids (80 m, 40 m, 20 m) of Western Australia

 

New Data: Crust 1.0 global crustal model

We have just added gridded CRUST1.0 to the Geosoft Geoscience Data Service (Powered by DAP).  

Fig. 1 - Sediment Thickness

CRUST 1.0 is A New Global Crustal Model at 1x1 Degrees. "Seismic tomography has been extensively used in various forms to determine the three-dimensional velocity structure of the Earth's mantle. The data used in these studies are surface wave (waveforms and dispersion measurements) and free oscillation (frequency shift) data as well as body wave travel times (arrival times from catalogues such as the ISC catalog and specially hand-picked long-period arrivals). For the majority of these studies, the crust has a significant impact on the observed seismic data but, at the same time, is too thin to be resolved by them. Most authors handle this by applying an assumed "crustal correction" to the data before an inversion for mantle structure. Since the inversion techniques can erroneously map crustal structure down to great depth (at least 250km), accurate crustal corrections to the data sets are extremely important." Visit https://igppweb.ucsd.edu/~gabi/crust1.html to learn more about these data.

Ref:  Laske, G., Masters., G., Ma, Z. and Pasyanos, M., Update on CRUST1.0 - A 1-degree Global Model of Earth's Crust, Geophys. Res. Abstracts, 15, Abstract EGU2013-2658, 2013.  (http://igppweb.ucsd.edu/~gabi/rem.html)

(If you like the viridis colour table used for this project, check out the Geonet Forum post and get the colour table.)

New Data: LCS-1 Lithospheric Magnetic Field Model

We have recently added a high-resolution global model of the lithospheric magnetic field derived from CHAMP and Swarm satellite observations to the Geosoft Geoscience Data Service (Powered by DAP).

LCS-1 is a global grid of the scalar magnetic field anomaly at Earth's surface (WGS84 ellipsod) on regular 0.25° x 0.25° grid in (geodetic) latitude and longitude, for spherical harmonic degrees n=14-185.  This data can be useful when studying super-regional trends, and as a backdrop on which to level and combine smaller-footprint terrestrial surveys. The LCS-1 data show features similar to those exhibited by the WDMAM2 and EMM2015 lithospheric field models truncated at degree 185 in regions where they include near-surface data, and provides unprecedented detail where they do not.

Publication: http://www.spacecenter.dk/files/magnetic-models/LCS-1/

Reference: Olsen, N., D. Ravat, C. C. Finlay, and L. K. Kother, LCS-1: A high-resolution global model of the lithospheric magnetic field derived from CHAMP and Swarm satellite observations, Geophys. J. Int., 211, 1461–1477, doi:10.1093/gji/ggx381, 2017   

Learn more about the Geoscience Data Service web interface for Geosoft's Public DAP Server and search for global geoscience datasets by keyword or location.

New SRTM gridded topography data

Shuttle Radar Topography Mission (SRTM) 1 Arc-Second Global gridded topography data is now available on the Geosoft Public DAP Server.

The 1 Arc-Second data provides a nominal 30m ground coverage, which is a significant improvement in resolution from the 90m global coverage.  The 1 arc-second data has gaps (holes) in some areas of steep gradient or poor reflectance.  We have left the holes as they are so that users know where the data has gaps.  If you need to fill the gaps, you can download the 90m SRTM data and use GRIDBOOL to replace the gaps with the 90m data which will automatically be resampled to 30m.

You can access this data using Seeker in your Geosoft applications including Oasis montaj, Target, and Target for ArcGIS. Learn more about DAP and how to access the SRTM data at www.geosoft.com/dap. Learn more about the data at http://topex.ucsd.edu.

Botswana Geoscience Portal

Geosoft is pleased to announce the launch of the Botswana Geoscience Portal, a partnership initiative with the Botswana Geoscience Institute and industry sponsors.

Developed and hosted by Geosoft, the portal provides free access to multi-disciplinary datasets from Ngamiland, a district in the country's northwest.

It is available online at: http://geoscienceportal.geosoft.com/Botswana/search.

 

Read more about this project: Botswana Geoscience Portal goes live 

QDEX Data: Access to spatial geoscience data from Queensland Government

The Queensland Government QDEX Data lets you search for and download large geoscience spatial datasets.

Learn more about QDEX Data, or connect and browse the available data.  

QDEX Data includes access to:

• seismic survey processed data and field data packaged by survey
• wireline log data packaged by well
• 3D geological and geophysical models
• airborne geophysical survey data including state, federal, open-range and open file company exploration surveys packaged by Aerial Geophysical Survey System (AGSS) number
• ground geophysical data, including gravity data
• geochemistry including drill hole locations, down-hole assays and geology, and assays of rock chips, stream sediment, soils and whole rock samples packed by broad region.

QDEX is powered by Geosoft DAP Server technology.

 

Statoil: Revolutionizing Gravity and Magnetic Data Management

Statoil has implemented an organized system for gravity and magnetic data which both specialists and generalists can use. Statoil geophysicist Christian Gram explains how it works and how it has made it easier for team members in Statoil's exploration operations to search for and find exploration data.

Watch the video  

Useful Metadata

What are all these XML files that get created with my datasets?  

Those contain auto-generated geospatial metadata. Metadata is "data about data".  

When an XML file is automatically created along with a database, grid, voxel or map, you can be sure that it contains some useful information, with ISO 19115 standard tags, that can tell you who, where, and how the data was created.

• The Project Name field is automatically populated with the path and name of the Geosoft Project File (*.GPF) where the dataset was created.  Since the folders in the path often are related the to the data, this can be useful information for when the dataset is moved around to other file systems and servers.  
• The name of the data creator and the date are also recorded.   
• Coordinate System information is available and is always synchronized with the Coordinate System of the dataset.
• "How" the dataset was created is often captured in the Lineage section. This can be used to easily identify a subset database or the type of gridding or filter that was used on a grid or voxel. 

No harm will come from deleting these small text files, but if you keep them they may become a valuable reference to you when you need them. 

Adding Bing Maps imagery to Geosoft maps

Bing Maps published its largest satellite release to date this past month, and with Geosoft’s latest software release, Oasis montaj and Target 7.5, Bing Maps imagery can be added as a map group.

Bing Maps is a web mapping service provided as a part of Microsoft's Bing suite of search engines and powered by the Bing Maps for Enterprise framework. Bing’s satellite release adds 165 terabytes of new data which cover 38 million square kilometres. Imagery from North America, South America, Africa, Australia, Europe and Asia are included.

To access the Bing Maps service within Geosoft, go to Seek Data > Add Bing Maps Imagery. You can add Aerial, Road or a Hybrid image as a map group. Note that you will need to be connected to the Internet and logged in with your Geosoft ID. Use of the service is subject to Microsoft's data license requirements. Learn more in this How-To article. 

When you are offline, a grey disconnected image will appear in place of the Bing Maps layer until you connect again. As the Bing Maps map group is powered by an online service, your map will display the latest data every time you use it.

Free Sources of Geoscience Data

Occasionally I am asked about my favourite (and most useful) sources of publicly available online data. Here are some of the ones I’ve used and can recommend:

• If you are working in Canada, the Geological Survey of Canada’s Geoscience Data Repository is a great source for regional and survey scale datasets.  It includes extensive Aeromagnetic and Electromagnetic data with simple instructions for viewing and downloading the data using a mapping application that is based on Geosoft DAP technology.


• Many global scientific and government organization host data online, or you can order it (sometimes for a small processing fee). A few that I have used include: Geoscience Australia - this site has many geophysical and geological datasets; USGS EROS Center - links to several data discovery tools; NOAA National Geophysical Data Center - Data by Discipline links to some great resources; and USGS LP DAAC - links to resources for ASTER data.


• Provincial and state geoscience surveys are also a great source of geoscientific data.  I recently attained a copy of New South Wales’ Explorers Directory 2012 with GIS data in Esri and MapInfo formats and a great selection of imagery.  For cultural and geographic data, the datasets provided with Esri and MapInfo applications are a good start. In the US, data.gov has a growing collection of spatial data in many formats.


• Compilations are often sponsored by a group of government and educational groups to make data publicly available and easily accessible, including numerous programs like Geomagnetism, a NOAA/CIRES project;  OneGeology, an international effort to collect geological data at 1:1 million scale; and ASTER GDEM, a joint NASA JPL program to collect high resolution ASTER data for the world.

I’ve posted on the Geosoft DAP Server before.  The SRTM data on the Geosoft DAP Server is very handy, and there are some other large, low-res datasets available here as well. Datasets can be windowed and reprojected and reformatted as needed with very little effort. 

I hope you find this list helpful. I’d be interested in hearing about some of your favourites!