Geoscience Reference
In-Depth Information
FIGURE 5.3
A geological scene under construction in the NAG IRIS Explorer SciViz system. Magnetic
anomaly data have been draped over the elevation model in the centre of the display and small point symbols
used to indicate geochemical samples. Around the edges are various interactive controls, including for light-
ing the scene (middle left) which induces shadows on the DEM, and a material properties editor (top right)
can change the reflectivity of the elevation surface to accentuate or dampen the effect of the lighting model.
mechanisms. Some of these systems and graphs can scale to massive datasets involving thousands
or even millions of records. Animation software offers perhaps the easiest means to explore data
that contain moving objects or in animating temporal sequences. These systems often do not
scale well to large volumes of data but may offer other advantages in terms of presentation and
dynamics.
5.2.4 g
eoViSualiSation
S
ySteMS
GeoViz became established as a field in its own right during the 1990s with the creation of spe-
cial interest groups and community-wide research agendas (e.g. MacEachren and Kraak, 1997).
Buttenfield and Mackaness (1991) described the early emergence of GeoViz in terms of several
needs including to search through huge volumes of data for relevant information and for explo-
ration; so from its beginnings, GeoViz has had a strong focus on discovery. A comprehensive,
long-term timeline of the history of cartographic and geovisual progress is provided by Friendly
(2009). A good cross section of relevant research themes is provided by Dykes et al. (2005). GeoViz
continues to refine its research agenda (e.g. Gahegan et al., 2001; MacEachren and Kraak, 2001;
Kraak and MacEachren, 2005; Andrienko et al., 2007), and a special GeoViz
commission has
been established under the auspices of the International Cartographic Association (ICA) (http://
geoanalytics.net/ica/).
Several geo-specific exploratory visualisation tools have been developed to date, including
GeoVISTA Studio
(Gahegan et al., 2002),
CommonGIS
(Andrienko et al., 2003),
STARS
(Rey and
