Digital Terrain Modeling – Color Shaded Relief Models

A color shaded relief (CSR) model utilizes chromo stereoscopic techniques to help emphasize the depth of the Z dimension from traditional shaded relief models that already portray the presence of an elevation difference.

Digital Terrain Modeling

Digital Terrain Modeling is the process of simulating or representing the relief and patterns of a surface with numerical and digital methods. It has always been an integral component to geology related fields such as geomorphology, hydrology, tectonics and oceanography but over the past decade has also become a major component to non geophysical applications such as GIS modeling, surveying and land use planning.

Terrain Models are derived from data represented by digital elevation models (DEMs) and can include shaded relief models, slope and aspect models, perspective scene generation, and drainage basin analysis (and other models).

Canadian GIS and Geomatics Resources

Canadian GIS and Geomatics Resources is an extension of my web site that I started back in 2005 after I noticed that there was a real need to have one good place on the web to help find Canadian geospatial resources. The site helps provide others with …

UTM Zones in Google Earth

UTM zones in Google Earth

Here is a neat little Google Earth file that has often been helpful on many of my field trips when I needed to know what UTM zone I was working in. Just open the file in Google Earth, then point and click your location to get info on that time zone. Before I found this neat little resource I was using a large JPG image that showed the zones witch I have available here.

I originaly found this file on Google but have not been able to find the original download source (have found other versions) so you here you can download my working copy here .


Every now and then I come across some little utilities that help to make things easier while working in the field and these pages are mainly my way of sharing them with others while creating a go-to place where I can easily find them when I need them. If you know of any other mapping related utilities like this then let me know and I may include it here on my site with the others.

Geographic Information Systems (GIS)

Geographic information systems commonly known as GIS has become a rapidly growing technological field that allows Geomatics Specialists to solve and model real world situations by incorporating digital spatial and associated tabular data. It is often defined as a comprehensive computerized information system made up of hardware, specialized software, spatial data and people to help manipulate, analyze and present the information used for storing, manipulating and analyzing spatially indexed information.

Geographic Information SystemsGIS operates on many levels and over the past decade has become an essential tool for most urban and resource planning and management organizations. On the most basic level, GIS can be used for simple digital cartography, to create various types of maps.

However the real power of GIS is through its abilities to use both spatial and statistical methods to analyze attribute and geographic information together. The end result of such an analysis can be vast amounts of derivative information, interpolated information or prioritized information.
Geographic information systems commonly known as GIS has become a rapidly growing technological field that allows
Geomatics Specialists to solve and model real world situations by incorporating digital spatial and associated tabular data. It is often defined as a comprehensive computerized information system made up of hardware, specialized software, spatial data and people to help manipulate, analyze and present the information used for storing, manipulating and analyzing spatially indexed information.

GIS technology can be used for scientific investigations, resource and utilities management, modeling, assessments, development planning, cartography and route planning and many other applications.. Some of these and other aspects of the GIS field are currently covered on this web site including projects related to spatial database modeling, Geostatistical spatial modeling, mobile mapping, cartography, and interactive web mapping.

Below are some examples of GIS from a few of the many GIS based projects that I have been involved with over the past few years. The links are to PDF versions of papers, presentations and or manuals related to GIS, I have many more, if anybody is interested in a particular topic then feel free to let me know, as I may have a document available related to that topic.

Examples of GIS

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Digital Terrain Modeling – Aspect models

Real world example of slope and aspect

Aspect is measured in degrees (similar to a compass bearing) clockwise from magnetic north.In digital terrain modeling the Aspect of a surface refers to the direction (azimuth) to which a slope face is orientated. The aspect or orientation of a slope can produce very significant influences on it, so it is important to know the aspect of the plane as well as the slope. Together the slope combined with the aspect of the surface can virtually define the surface plane completely in digital terrain modeling.

Aspect is measured in degrees (similar to a compass bearing) clockwise from magnetic north. A surface with 0 degrees Aspect would represent a north direction, an east facing slope would be 90 degrees, a south facing slope would be 180 degrees and a west facing slope would be 270 degrees.

Aspect map derived from a digital elevation model of Lismore, Nova Scotia

The example shown to the left (for larger image click here) is a raster aspect model of Lismore, Nova Scotia was derived from a digital elevation model (DEM) calculated using PCI Geomatica remote sensing software. It is represented with a grey scale color ramp and helps to indicate what direction slope faces are orientated.

The image above is of an actual bedrock cliff with some technical information embedded onto the image to help better understand slope and aspect relationships. The black arrow represents the slope or the measured angle that the rock is dipping towards.

The aspect is the orientation that the arrow (slope) is pointing with respect to North, therefore the aspect for this slope would be in an easterly direction and often represented by 90 degrees. The blue arrows represent the X, Y and Z dimensions that the combination of both the slope and aspect would use to represent the terrain features.

Example of an Aspect Map

The image below is an Aspect Model that I derived from a digital elevation model (DEM) of Lismore, Nova Scotia. The aspect values of the slopes of the DEM are represented in the model by a 0-255 grey scale color ramp. Click here to learn a little more about Aspect Models and how the image below was created.

Aspect map derived from a digital elevation model of Lismore, Nova Scotia