![Page 1: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/1.jpg)
Using ArcGIS to Assist in
Geomorphic Surface Mapping
Michael Bigsby
Tetra Tech, Inc.
June 30, 2016
![Page 2: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/2.jpg)
Background
• ArcGIS was used to perform desktop mapping of
geomorphic surfaces of a stream valley
• Mapped surface data layers were edited on an iterative
basis to incorporate each dataset into the surface mapping
process
• Each line of evidence was evaluated independently using
serval tools and features of ArcGIS in order to distinguish
individual surfaces
![Page 3: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/3.jpg)
Objective
• Demonstrate how GIS is used to develop a geomorphic
interpretation of stream valley
- Features of ArcMap used in mapping process
- Spatial Analyst
- 3D Analyst
- Analysis Tools
- Conversion Tools
![Page 4: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/4.jpg)
The Approach
• Fluvial geomorphology:
The study of the origin
and evolution of stream-
related landforms
• A geomorphic surface is
an area formed by
similar physical factors
related to morphology
and time
• Fluvial systems are
complex and dynamic
![Page 5: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/5.jpg)
The Approach
Layering of multiple datasets
![Page 6: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/6.jpg)
Methods
• Multiple lines of evidence:
- Aerial photos (recent and historic)
- Contour lines
- Stream channel gradient
- Slope steepness
- Geomorphic setting
- Channel width
- Water depth
- Water velocity
- Land use
- Anthropogenic impacts (e.g. dams, bridges, channel straightening)
![Page 7: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/7.jpg)
Methods
Use aerial photography to digitize stream channel
![Page 8: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/8.jpg)
Methods
DEMs are processed using several Spatial
Analyst tools…
![Page 9: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/9.jpg)
Methods
![Page 10: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/10.jpg)
Methods
![Page 11: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/11.jpg)
Methods
DEM + Contour lines + Hillshade
![Page 12: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/12.jpg)
Methods
3D Analyst is used to create lateral cross-sections and
longitudinal profiles
![Page 13: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/13.jpg)
Methods
3D Analyst
![Page 14: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/14.jpg)
Methods
![Page 15: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/15.jpg)
Methods
Reach 1
Reach 5
![Page 16: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/16.jpg)
Methods
![Page 17: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/17.jpg)
Methods
![Page 18: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/18.jpg)
Methods
![Page 19: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/19.jpg)
Results
![Page 20: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/20.jpg)
Methods
Field confirmation of
desktop mapping
• GPS data can be
used to spot-check
the DEM
• “See” if mapped
surfaces match the real world
![Page 21: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/21.jpg)
Conclusions
• Some limitations exist
- Quality of GIS data
- Typically requires many iterations to reach a level of
confidence in geomorphically complex areas
- Difficult to characterize small-scale variations
![Page 22: Using ArcGIS to Assist in Geomorphic Surface Mapping · •Fluvial geomorphology: The study of the origin and evolution of stream-related landforms •A geomorphic surface is an area](https://reader030.vdocument.in/reader030/viewer/2022041105/5f064aaf7e708231d417423d/html5/thumbnails/22.jpg)
Conclusions
• Many benefits
- Allows detailed visualization of complex fluvial patterns
- Synthesis of multiple lines of evidence
- Key to developing a sampling plan
- Results can be refined with new data
- Refined with field-collected data
- As new data is incorporated, Spatial Analyst can be used to
perform time-series analysis
- Datasets can be used a inputs into hydrodynamic models with
the outputs of the models being displayed in ArcGIS