Wednesday, November 25, 2020

Warford Ranch volcano (Arizona) sUAS mapping


We recently visited the Warford Ranch Volcano which is a low shield volcano that is part of the Sentinel-Arlington volcanic field of southwestern Arizona. It is about 3 million years old. It was a favorite field trip destination of Prof. Ronald Greeley. Shelby Cave worked on the Sentinel-Arlington field for her Ph.D. dissertation under the supervision of Prof. Greeley and after his passing she worked with Prof. Amanda Clarke.

Google maps location for Warford Ranch (NW of Gila Bend, AZ).

Professor Clarke is teaching the Advanced Field Geology course and she took the group to Warford Ranch volcano to examine its volcanology. I did some UAS-mapping to help with the documentation. This blog entry presents some of the products of the overflights with our Mavic Air and Phantom 4 Pro.

Oblique overviews

I flew the Mavic Air high to get some views over the volcano to assess its general form and the relation to adjacent landforms and geology.

View to the north. The cars are lower left are in our parking spot. LINK to jpg

View to the south-southwest. LINK to jpg

View to the south-southeast. LINK to jpg

Fissure zone on SW side of higher topography. People for scale. Not sure the purpose of the excavation. LINK to jpg

Masked and socially distanced field work. LINK to jpg

Video overflight.

sUAS mapping

Along with the free flying overviews, I flew in mapping mode (using the PX4D mapper app) over most of the volcano taking 1778 images in mapping mode. I processed those in Agisoft Metashape to produce a colored point cloud, digital elevation model, and orthophoto. The latter two can be the basis of more mapping in ArcMap.

Tour of the data and its processing in Agisoft Metashape and ArcMap.

Map downloads

Hillshade overview. 600 dpi pdf download: LINK.

Ortho image overview. 600 dpi pdf download: LINK.

Hillshade of peak area. 600 dpi pdf download: LINK.

Ortho image of peak area. 600 dpi pdf download: LINK.

Map data downloads

  • 0.1 m/pix DEM and hillshade downloads (tif): LINK
  • 0.1 m/pix orthoimage download (tif): LINK

Topographic profile

The video presented above discusses the topographic profile cut from the DEM in ArcMap towards the end. This would be the basis for the geologic cross section, preferably without vertical exaggeration.

Topographic profile location. Bent along the path of our Saturday November 22, 2020 tour. LINK to png.

Topographic data text file: LINK and MATLAB script to plot it: LINK

No vertical exaggeration. Link to png.

Vertical exaggeration. LINK to png

For the October 2021 field work, we are trying to use STRABOSPOT for the digital mapping. I prepared a few items to help:

  • Simple tutorial. The students need to do all but the very last step (uploading after the field) BEFORE we go to the field: PDF
  • Video tutorial. I recorded all of this on the browser and the tablet with narration.

Friday, November 6, 2020

Thank you to the American Geophysical Union and colleagues for the Paul G. Silver Award for Scientific Service

Thank you for this great honor of the Paul G. Silver Award for Outstanding Scientific Service. Recognition from AGU’s Geodesy, Seismology, and Tectonophysics Sections adds to its heft. I am happy that Paul’s family is represented. I know we have all benefited from Paul Silver’s leadership and legacy. I was fortunate to meet him on several occasions and appreciated his wit and the spark that drove major science activities on which I was later able to contribute. I am humbled to be in the same list as those who have been awarded before. Congratulations to Doug Toomey--the other recipient this year of the award.

This recognition reflects the efforts of many of my colleagues with whom I have shared numerous projects. I know that many of you are strongly dedicated to serving your families and the communities of your private and scientific lives. I hope that this honor can lift us all as we acknowledge efforts to coordinate activity for our broader good helping others.

It has been satisfying and stimulating to help with major earth science efforts and organizations including GeoPrisms, Southern California Earthquake Center, EarthScope, AGeS - Awards for Geochronology Student Research, and OpenTopography. I share this recognition with collaborators and friends in those organizations. Colleagues in the National Science Foundation and US Geological Survey have worked mightily to sustain support.

I was inspired to serve by the example of many, including mentors Dallas Rhodes, David Pollard, and Manfred Strecker. Arizona State University’s School of Earth and Space Exploration Prof. Jim Tyburczy showed me a firm and balanced approach to leadership. My service as associate and deputy to SESE Directors Hodges, Elkins-Tanton, and Wadhwa has given me an opportunity to learn about academic administration and help students, faculty, and staff.

I want to close with a thank you to family including my sister and her husband and their daughters. Our parents--a teacher and a mechanical designer--steadfastly supported me. In their retirement, they served as the Los Ranchos (New Mexico) farmer’s market managers. Their dedicated and steady service made the market an institution. Thank you to my wife Amanda for her love and clear thinking which keeps us going in the right direction.

Here is a video of this speech: LINK