Some of the elements of model building and visualisation are illustrated here. A free software viewer available from Leapfrog™ HYDRO makes it possible to view the model in a variety of ways.

Figure: shows extent of model, and topography

The model area is highlighted and lies between Banks Peninsula in the foreground and the foothills in the background.

What is a 3D model?

In computers, the term three-dimensional (3D) describes an image that provides the perception of depth as well as length and height. A 3D model is a mathematical representation of a surface or object that can be made interactive. Models can be rotated, moved and dissected like real objects. They can be used for computer simulation of groundwater flow through an aquifer system e.g. the Canterbury plains.

The structure of the completed model above is based on the geological history of the Canterbury plains – periods of glaciation separated by warmer (interglacial) periods. The geological history is interpreted from bore logs that describe the materials (e.g. gravel, sand silt, peat) encountered when drilling for water. Sea levels during glacial periods were about 120m lower than the present day sea levels. During interglacial periods when sea levels were high marine fine sediments were deposited along the coast and are preserved between Lake Ellesmere and the Ashley River.

The vertical scale for this model and the models on the related pages is exaggerated by 30 times to 50 times to see the model structure more clearly.

Disclaimer

Information used for this geological interpretation comes from many sources of variable accuracy and is subject to modification as further information is collected and interpretative errors (coding) are discovered. Depth to the base/top of the geological formations and thickness of the formations may therefore be inexact. Accordingly, the models/sections presented on this website should be regarded as a regional guide and not a substitute for all detailed site-specific investigations.