Friday, December 2, 2016

Fall 2016 Semester Party

In keeping with my tradition of having a semester party for every class I teach, GEOS 4533 Petroleum Geophysics students gathered at Bear's Place in south Fayetteville for some refreshment and camaraderie.

Students, my wife Dolores (far right) and the professor.

The Bear himself telling a story in the kitchen. Great time thanks!


Friday, November 11, 2016

Cushing OK Earthquake

On 7 Nov 2016 there was a magnitude 5.0 earthquake (EQ) at 5 km depth about 2 km W of Cushing, Oklahoma. The earthquake was felt by many in my town of Fayetteville, Arkansas. Although I did not feel the EQ myself, I was interviewed by three local television stations to provide some insight. The interviews went well and appeared on Nov 8.

This got me thinking about simulating the EQ. A few months ago I set out to learn a bit about the python computer language. In the process I found some remarkable open source codes. The one on point here is fatiando a terra written in 2012 by (then) PhD student Leonardo Uieda. Leo is a research department all on his own.

Anyway, one thing fatiando does is elastic seismic modeling and there is a demo script (seismic_wavefd_elastic_psv.py) in the cookbook. This generates a neat simulation of elastic waves in a crust/moho model and the (x,z) seismic reading from one seismometer. It is a movie, but here is the last frame.

Fig 1. Default simulation result from fatiando script seismic_wavefd_elastic_psv.py 

You can see all the elements are here to simulate the Cushing EQ, we just need to change a few things. Specifically:
     (1) Crust (granite) properties can be localized using a deep well in Osage County, OK that drilled almost 2 km of granite. The params are vp = 5970 m/s, vs = 3500 m/s and density 2650 kg/m^3.
     (2)  Crust thickness in N Oklahoma and Arkansas is about 45 km thick (reference, figure 7).
     (3) The seismometer should at Fayetteville, 240 km from the EQ.
     (4) Since all the action in Fayetteville is over by 85 seconds, limit the simulation to 100 sec.

With these edits and running the python script now gives the Cushing EQ as felt in Fayetteville AR case. Very cool. Thank you Leo.

Fig 2. Simulation result for 7 Nov 2016 Cushing EQ as felt at Fayetteville AR. 


Saturday, October 22, 2016

SEG Dallas 2016 and Beyond

It was my intention to live blog from the SEG annual convention in Dallas, but it turns out the current version of iPhone iOS crashes the Blogger App (hello? Google are you listening?). So it had to wait till my return to Fayetteville.  Here goes.

For the last couple of years there has been little new on this blog except periodic updates on the the great oil crash of 2015-?. This is largely due to my violation of the Voltaire maxim: "Keeping busy is a poor substitute for accomplishment." My way of keeping busy was serving as President Elect, President and Past President of SEG from 2014-2016. This came to an end on Thursday Oct 20 when I passed off the SEG Board of Directors to become merely a former SEG President. It is a subtle distinction, but Past President is an SEG Board position, while former President is a condition.

I have been thinking about my SEG volunteer career, which we can list here in stratigraphic order (youngest first)

     • Past President (2015-16)
     • President (2014-15)
     • President Elect (2013-14)
          • Chair SEG Executive Director Search Committee
     • Distinguished Instructor Short course (2012)
          • Writing DISC book (2011)
     • The Leading Edge Editorial Board
     • First Chair of SEG Online Committee
     • Editor of Geophysics (1999-2001)
     • Assistant Editor of Geophysics (1995-98)

So there we have it, basically 20 years of service to the SEG. An odyssey that ended last Thursday in Dallas. Of course it is not really over, I am now Chairman of the SEG Advisory Committee and member of Nominations Committee as well as the Honors and Awards Committee. So beings a 5 year wind-down. Yikes.

Beyond the SEG Board, my full attention is dedicated to a new role as Chairman of the Department of Geosciences at the University of Arkansas. I have been at UA since 2012, but only stepped into the new role on July 1, 2016. When asked "what is the job like?", I usually reply it is like pouring syrup on a table; there are not natural boundaries and if you get it under control in one place it oozes out somewhere else. But I like a challenge and have lots of time on my hands.

The Dallas meeting was also the launch of the 3rd edition of my book Elements of 3D Seismology, now an SEG publication. 

My lovely wife Dolores Proubasta could not join me at the Dallas meeting due to pet obligations. This one arrived a few days before I headed out for Dallas. A rescue, he is about 10 years old and blind. Keeping with the Odyssey theme, we have named him Argos.

My last SEG Board meeting as Past President of the SEG.

A night out with my good Argentinian friend and fellow Board Member Gustavo Karstens. 

I have always been a note-taker. As my presidential year approached I began keeping a dedicated meeting journal. This is the first entry. 

With my dear old friend John Stockwell. We meet in 1986 when I came to Colorado School of Mines to work on a PhD with the Center for Wave Phenomena research group headed up by Norm Bleistein and Jack Cohen (great guys).

Another great friend, Brian Wallick, this time from my time at Saudi Aramco. 

Prof. Hua-Wei Zhou, Chairman of the Department of Earth & Atmospheric Sciences at the University of Houston. We had a long conversation comparing notes as department chairmen.

Group photo from the SEG Former Presidents Luncheon.