A Modelbuilder Workflow for Automating Contour Generation from High-Resolution Elevation Data in a Mosaic Dataset

Abstract

This project streamlines the topographic-contour generation process for the New Mexico Bureau of Geology and Mineral Resources (NMBGMR). Historically, the NMBGMR generated contours internally to leverage access to high-resolution elevation rasters and maintain control over the level of detail and smoothness. Creating contours from elevation data involves a multi-step workflow requiring manual input, mosaicking, reprojecting, clipping, appending data, field calculations, and generalization. This work develops an automated geoprocessing tool using ModelBuilder in ArcGIS Pro, replacing manual steps with a simplified, repeatable process. The model uses a mosaic dataset to efficiently manage the multiple raster tiles used to generate contours. Integrated into the tool is the optional capability of unit conversion, allowing for the creation of contours in either meters or feet, automated clipping to a designated map extent, contour creation at designated intervals, appending to an existing feature class, and attribute calculations. Testing on map areas with steep, mountainous terrain confirmed that the model accurately replicates the original workflow while reducing complexity. The outcome is a user-friendly tool that standardizes contour creation and improves the efficiency of GIS specialists/cartographers when building map kits used by field geologists. This advancement allows for consistent and rapid production of accurate, map-scale appropriate contours to provide topographic context for the overlying geologic data and supports the production of high-quality cartographic layouts.