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SDAG Monthly Meeting
Wednesday, March 21, 2018

Location: Phil's Barbecue Event Center, Point Loma
3750 Sports Arena Boulevard
San Diego, 92110

Phil's Barbecue Event Center is located in the back of the shopping center - behind Phil's BBQ Restaurant.
happy hour
5:30pm -
Social hour  

Menu: Pulled Pork and Tri-tip Sandwiches. Cash bar.
6:30pm -

Cost: $40.00 for non-members, $35.00 for members, $20.00 for students. if pre-registered by the deadline, $5 extra if you did not make a reservation. Click the SDAG member checkbox on the reservation form if you are a member.

Reservations: Make your reservation online by clicking the button below no later than NOON, Monday, March 19. RESERVATIONS CANNOT BE ACCEPTED AFTER Monday at noon. Late reservations/cancellations are preferred over walk-ins or no-shows. Fees payable at the meeting or pre-pay with PayPal.
As a new payment option, there will be a phone credit card reader at the meeting.

If you are a current SDAG member and are not getting e-mail announcements,
make sure the SDAG secretary has your correct e-mail address.

7:30pm -

Speaker: Pat Abbott, Ph.D.

"Sturzstroms: Catastrophic, High-Velocity, Huge-Volume Debris Flows"

Abstract: Sturzstroms form as massive rock falls that convert into highly fluidized debris flows that travel far and kill in great numbers. Rock falls with volumes in excess of 1 million cubic meters may shatter and flow distances 25 times farther than their vertical fall. They have been observed moving 175 mph, even running up and over sizable hills and ridges lying in their paths as at Nevados Huascaran, Peru in 1970 where 18,000 people were killed. These long-runout flows imply that the kinetic energy of a fall is preserved via low coefficients of internal friction within the flowing mass. The best explanation of how they work is via acoustic fluidization.

This phenomenon was first described following an 11 September 1881 event in Switzerland where 10 million cubic meters of rock dropped 2,000 feet and then flowed 1.4 miles as a dry mass moving 110 mph, destroying 2/3 of the village of Elm and its inhabitants. The German geologist Albert Heim called the flow a sturzstrom (in German, sturz means "fall" and strom means "stream"). Heim described many counterintuitive features within the sturzstrom deposit. For example, the shattered rock although broken into innumerable pieces still preserved its bedrock geometry and stratigraphic order although broken into a jigsaw-puzzle fabric.

A classic example near San Diego is the Blackhawk "landslide" that flowed from the San Bernardino Mountains onto the Mojave Desert floor 17,000 years ago. Many of us had the good fortune to go on a Blackhawk field trip led by Martin Stout where we walked down the head scarp and along the flow path; this trip dispelled many interpretive myths that still appear in the geologic literature today.

In the latest Miocene and earliest Pliocene stratigraphic section in Split Mountain Gorge in Anza-Borrego Desert there are excellent exposures of two huge sturzstrom deposits, one flowed subaerially and the other subaqueously. Many diagnostic features of each will be shown in the talk.

Pat Abbott has a Ph.D. degree in geology from The University of Texas at Austin. He was a long-time Professor of Geology at SDSU. Currently he is an author for McGraw-Hill (Natural Disasters, 10 editions) and Sunbelt Publications (The Rise and Fall of San Diego) and he leads journeys to all continents and across all oceans for The Smithsonian. Dr. Abbott recently published his third book called "Geology of Mission Trails Park" and it is available at the Park's Visitor Center.

Upcoming SDAG meetings - 2018

April 18: Student Presentations

May 16: Monte Marshall

June 20: TBD

Meetings are usually scheduled for the 3rd Wednesday evening of the month. Meeting information on this website is normally updated the second week of the month.

If you have any information, announcements, ads or suggestions for an upcoming newsletter, please submit it to Adam Avakian, (2018 SDAG Secretary). Any news regarding upcoming events that may be of interest to the Association or news of your business can be submitted. The submittal deadline for the next SDAG newsletter is the last Friday of the month.
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