Field blog: Welcome to a field season at Ledi-Geraru, Afar, Ethiopia! by Erin DiMaggio

Erin DiMaggio was invited to write a field blog for the GeoPrisms Spring 2013 newsletter. She presents a nice set of highlights from our recent field season at Ledi-Geraru, Afar, Ethiopia. The link is here: http://www.geoprisms.org/newsletters/50-newsletter-articles/rie/ears/399-field-blog-afar-spring2013.html.

LaDiCaOZ and Lateback: reconstructing horizontal offsets in topography websites for tools

Dr. Olaf Zielke developed some very useful tools for interacting with high resolution topography for horizontal back slip of offsets due to earthquakes. These were the tools for the science results presented in:

• Zielke, O., Arrowsmith, J R., Grant Ludwig, L., Akciz, S. O., High resolution topography-derived offsets along the 1857 Fort Tejon earthquake rupture trace, San Andreas Fault, Bulletin of the Seismological Society of America, doi: 10.17850120110230, vol. 102 no. 3 1135-1154, 2012.
• Zielke, O., Arrowsmith, J R., Grant Ludwig, L., Akciz, S. O., Slip in the 1857 and earlier large earthquakes along the Carrizo Plain, San Andreas Fault, Science, DOI: 10.1126/science.1182781, p. 1119–1122, 2010.

He also documented the approach and the software in this paper:
Zielke, O., and J R. Arrowsmith, LaDiCaoz and LiDARimager -MATLAB GUIs for LiDAR data handling and lateral displacement measurement, GeoSphere Special issue on high resolution topography, v. 8, no. 1, p. 206221, doi:10.1130GES00686.1, 2012.

Olaf is now at KAUST. His email address is: Olaf.Zielke@kaust.edu.sa.

He has made the supplemental on line material from the Geosphere paper available here.
And, the LaDiCaoz_LiDARimager tools and information is available on this dropbox link

This research was supported by the US National Science Foundation, the US Geological Survey, and the Southern California Earthquake Center.

announcing a summer school: Understanding Earth-Surface Processes in the Alpine Environment from High Resolution Topography

I am happy to be working with a great team on the

Understanding Earth-Surface Processes in the Alpine Environment from High Resolution Topography: European Geosciences Union Summer School 2013

Paolo Tarolli is our leader. It should be a fun school and quite interesting to catch up on the latest science and technology.

Collecting some links on the North Korean nuclear test

Valuable information about North Korea's nuclear test comes from seismological recordings of the shock waves produced in the event.

One of the interesting things is that because the North Korean nuclear tests are basically done in the same place, seismograms of the events at long distances have quite similar characteristics. Their amplitudes, however, do vary with the increasing yield of the events.

Here are a few links I have come across:

• Physics Today commentary
• IRIS Special event page on the event
• IRIS Recent Earthquake Teachable Moments on the event
• US Geological Survey report on the event
• NORSAR records of the last three DPRK nuclear tests (2006, 2009, and 2013)
• Comparison for the nearest real-time broadband seismometer (in China) for 2009 and 2013 nuclear tests (by Andy Frassetto, IRIS)

How do we know it was an explosion and not an earthquake? First of all, that part of North Korea is not known for historic earthquakes. Secondly and more to the point, with seismometers arrayed around the source area regionally and globally, the explosion will cause all of the first motions to be AWAY from the source. If it is an earthquake, two quadrants will be pulled IN towards the source and two quadrants will be pulled out ("double couple").

--disclaimer: this is not my area of expertise, but I do find it fascinating. To some degree, monitoring of nuclear tests using seismology has driven the development of seismology and seismic networks and that lets us learn a lot more about earthquakes globally.

Paleoanthropology research in the Afar, Ethiopia

I just got back from some fun field work in the Afar, Ethiopia. Here are some pictures. Our project there is called the Ledi-Geraru Research project. The research is done in collaboration with Kaye Reed and Chris Campisano from the Institute of Human Origins / School of Human Evolution and Social Change as well as with Ph.D. students Erin DiMaggio and Dominique Garello. Erin is just finishing up a substantial Ph.D. effort on the geology, stratigraphy, and tephrachronology of rare Pliocene units (about 2.9-2.7 Ma) that critically span a time gap otherwise mostly missing in the region. Dominique will be working with Chris Campisano and I on the geology of the Ledi-Geraru, as well as this drilling project.

Here are a few other posts on this topic:
We started this project with Charlie Lockwood and miss the chance to share its successes with him.
Here is an old page with maps
Here are many pictures from over the years:
Ethiopia and Afar region (2002)
Ethiopia and Afar region (2004)
Ethiopia and Afar region (2005)
Ethiopia and Afar region (2006)
Ethiopia and Afar region (May 2008)
Web-sized images for Ethiopia and Afar region (November 2008); Ethiopia and Afar region (November 2008) full size images
Web-sized images for Hadar Field School (2009); Hadar Field School full size images
Afar region 2012
Afar region 2013

OpenTopography update at AGU 2012

At the fall 2012 American Geophysical Union meeting, I represented OpenTopography at the New lidar technologies and vision for the future town hall along with our colleagues from the National Center for Airborne Laser Mapping as well as Chris Crosby and the TLS program at UNAVCO.

Thanks to all who attended. It was a nice forum to talk about LiDAR as supported by the EAR program at the National Science Foundation (Thanks especially to Russ Kelz).

Here is my presentation which provides a very short update on OpenTopography and our renewal: pptx pdf. Here is an MP4 of my practice from the night before (not the greatest clarity but gets the point across: 13 Mb MP4)

Tours in Google Earth around Arizona highlight aspects of its geology

As a part of my final set of lectures for the 2012 Structural Geology class, I used my Camtasia to record some fly overs of Arizona from inside Google Earth.

In the first video (29 Mb MP4 format video file or on youtube), I tour from inside the Grand Canyon to around Flagstaff, Prescott and Jerome and finish over south Phoenix.

In the second video (29 Mb MP4 format video file or on youtube), I tour from the White Mountains of eastern Arizona over to Phoenix and on down to finish above Tucson.

These videos are not narrated, but they are then embedded in the narrated lecture on the Cordilleran geologic history (post Eocene) that I developed for the class (look around 20 minutes):
Tectonic history of the western North American Cordillera (from Eocene) ppt
video narration--big file (100MB)--may need to right click and save to local disk. Lecture narrated video on Youtube

videos

I hope these might be useful for others.