1.4.1 Using the OneGeology Portal
1.4.1.1 Viewing existing (portal) map data
The OneGeology portal is found at: http://portal.onegeology.org/ and is accessible as either an English (the default) or French language service.
You will need to use Internet Explorer 6 and above, Firefox 2 and above or recent versions of Safari, Opera, and Chrome. You will need to enable JavaScript and allow pop-ups.
When you open the portal you get a map of the world, the Blue Marble: Next Generation+Topo+Bathy (Terra/MODIS) (http://visibleearth.nasa.gov/view_detail.php?id=7105), but no geology. To view any existing geology maps you need to click on the View Layers option [1], to open the OneGeology catalogue listing.
[2] Click on the + buttons to expand the levels. Select a map by clicking on the box to the left of the map you wish to view. A tick will appear.
[3] Select all the map layers you wish to view before closing the catalogue listing. The selected maps should then be visible.
You may navigate around the map using the GIS tools found in the top left hand side of the menu bar. The functions of these tools is as follows:
[4] Zoom in — click on this image and then click on the world background map to zoom in centred on the clicked location. Click and drag a rectangle to zoom to a specific area.
[5] Zoom out — click on this image and then click on the world background map to zoom out centred on the clicked location. Click and drag a rectangle to zoom out from a specific area.
[6] View full global extent — click this image to start again with a view of the full world background map.
[7] Pan by clicking and dragging the map to move — click this image and then click and drag on the map to move to a different area (north, west, etc)
[8] Return back to previous map view
[9] If you have gone back to a previous view, you may use this tool to go forward.
[10] Refresh the map view
[11] Use this tool to get more information about the active map layers (this is termed a GetFeatureInfo request). Select the tool and click the map to open up a new window with detailed information about the geology at that point. The information returned and format of the information varies from map to map and layer to layer dependant upon how much information the provider organization wishes to display and the capabilities of the service.
To view metadata about the map layers and to change the way the layers are displayed you need to:
[12] Click on ‘ Active layers properties’ menu option. This will open a list of all the map layers that you have selected to be viewed in the portal.
[13] Within this dialogue menu you can manage the individual layers in the following ways:-
[14] Show or hide the map layer.
[15] Move the map layer up (so it lies above other layers and may obscure them).
[16] Move the map layer down (so it lies beneath other layers and may be obscured by them).
[17] Zoom to the extent of the map layer to make that particular map layer fill the centre of the map browser.
[18] Delete the map layer from the view (you can add it back again later).
[19] Change the opacity of the map layer (use the slider rule to change the % value to make underlying maps visible) so that it is possible to see through a layer to underlying layers where they overlap
[20] Click on this arrow to get more information about a layer, for example:-
- The data owner
- The layer title
- The legend of the map layer
- Information about the layer data and other digital data services of the data provider
- TC211/ISO 19115:2003 or FGDC metadata for the layer
- The service URL (you can use this URL to view the OneGeology WMS layer in any WMS client as described in later sections).
This (above) information is harvested automatically by the portal client software from the GetCapabilities response document of the WMS.
New functionality
Go To: Click on the 'Go To' link to open a dialog box that allows you to zoom to an area by place name or Longitude and Latitude coordinates
In the first example (below) we enter Dominica in the 'Localisation by Name' text box, then click the 'Go to' button to the right of it. This opens a second window that shows all the matches for Dominica in the OneGeology portal gazeteer. Select the place name you want by clicking on it and the portal will zoom to that location. Note the portal only zooms to the area, it doesn't open any available geology layers in that area.
In the second example (below) we use the 'Localisation by Coordinates' form and enter 172.85 in the 'Long:' text box and -43.73 in the 'Lat:' text box and then click the 'Go to' button to the right of them. The portal will then zoom to the area of interest. Note the portal only zooms to the area, it doesn't open any available geology layers in that area. In this example we already had the geology of New Zealand as an active layer.
Section last modified : 07 September 2010.
