Using DTM-MERGE in Terramodel

Terramodel has a nice feature that can be used to update small survey into an existing dataset. For example, we have data of an area of 1000m by 1000m. Work was done to a portion of 100m by 50m in that area. A survey to update the data was then done in that small portion.

In Terramodel, we can take the original data and use the DTM-MERGE command to update the new data into the existing dataset.

1. Type "merge" at the command line. (The command can also be accessed via DTM pulldown menu)


2. An Input box as below will appear. If you already have your data in the proper layer, just select the appropriate layer. Note that the outside layer is the existing dataset. The new survey you want to update should be your inside layer. The merged layer will be your updated data.


3. That's it! The new data will overwrite the old data where the new data exist. The rest of the dataset remains. So you have an updated dataset.

There are several things to note in order to make sure this works. Firstly, make sure your link setting is set properly to represent the point intervals of the survey. Secondly, you need to do one survey area at a time. If you surveyed 3 areas, seperate them into 3 layers and update them one by one.

Good luck!