Thursday, August 29, 2013

UArk Physics/Geology double major... Approved!

At spring 2013 commencement for the University of Arkansas Fulbright College of Arts and Sciences, I happened to sit next to a couple of physics professors.  Lucky me, because I had been thinking about cooking up a physics option for geology undergraduate students.  Dr. Gay Stewart was very encouraging.  We set up a coffee meeting, then had another, and another.  She quickly locked into the idea of double major, not just a minor.  After we had the rough outline, we brought in Dr. Matt Covington, a new Geosciences faculty member and a physicist by training (he did his PhD in Astrophysics).  By late summer it was ready to present to Geosciences department chairman Ralph Davis, who made some suggestions but also strongly supported the plan.  Last Monday the plan was emailed to the entire Geosciences faculty.  We got important feedback from Drs. Guccione and Boss, and these were quickly incorporated into the plan.

Wednesday of this week we had the first faculty meeting of the academic year and the Physics/Geology Double Major was top of the agenda. The University of Arkansas is never likely to have a geophysics undergraduate degree, but that is fine.  It can be persuasively argued that geophysics is best treated as a graduate degree, and that undergraduate years should be spent on more fundamental studies.  This is particularly the case with petroleum geophysics that is aimed at a terminal MS degree. I explained to the assembled faculty that the double degree would take the same time as a single degree (8 semesters), would have the same number of total hours as a single degree (120), all by judicious use of elective hours in both degree programs.  And it would be a solid degree on both sides, not something watered down.  Physics all the way through quantum mechanics and senior project; geology all the way through field camp.  The student who completed such a program would be attractive to the top geophysics or quantitative geology programs in the country.  And is can all be accomplished with existing faculty and resources.

The thought here to catch a few early physics majors who want to have a specialization that benefits from physics training.  It might be possible that a geology major could get into this double major, but it is unlikely since few geology students have quantitative skills necessary for advanced mathematics and physics required.

Anyway, the vote was taken: Unanimous yes in support of the new Physics/Geology double degree program.  Physics had already given approval thanks to the tireless efforts of Gay Stewart.  One degree, two majors.  Still much work to get it in the catalog and recruit a few good students.  So it begins.

27 Aug 2013 form of the Physics/Geology double degree.  Now we just need a few of strong students.

Monday, August 26, 2013

Geophysics @ UARK: It's alive!

Today began the first applied seismology class at the University of Arkansas in a very long time.  Perhaps since the 1980s.  Who knows? The name is simply Geophysics, but the scope is an ambitious overview of petroleum seismology concepts and methods, a lead-in to the 3D seismic interpretation course taught in spring.  Let the learning begin!

If you like, you can have a look at the syllabus.

Initial meeting of Geophysics class in a crowded mineralogy lab with 40 seats busting at the seams.  We have been moved to a 70-seat classroom, a welcome chance to spread out a bit.

Sunday, August 4, 2013

Old Main seismic

Thursday 1 August 2013

Caleb, Richard and Chris made the first fledgling seismic field efforts with new Geometrics Geode equipment.  It was just a test, but a symbolic one on the front lawn of Old Main, the University of Arkansas signature building completed in 1875.

Old Main shot record composed from 3 shots into a 24-phone spread.  Increasing offset direction is NE. Reference velocities are indicated by yellow line (335 m/s, air wave speed) and red line (1500 m/s, water wave speed). 

Old Main shot record scanned for dispersive surface wave phase velocities.  The characteristic curves can be used to analyze for subsurface layering.  

The test was laid out as a walk-away noise test with 24 single component geophones spaced 1 m apart, an off-end shot 1m from the last phone, then 2 further shots at 25 m and 40 m from the first shot location.  Shot walk-away direction is NE. As a source, we used a sledge hammer striking a 1" thick steel plate. One thing we determined for sure, the source plate needs a tough rubber coating to hold down air waves: It was very hard on the ears to be the source hammer man!

Google Earth view of seismic test location.  The Geoscience department is currently housed in Stone House South, but moving to renovated Ozark Hall in August 2013.

This was the first time for Caleb and Richard to lay out a seismic profile, plant geophones, wrestle the cable into place, and all the rest.  They will be the core of my seismic team and quickly be able to train others.  Here are a few photos of them in action.

All of the gear fits nicely in the back of my old 1989 Dodge Dakota. But we may need a modern geophysical truck for more remote locations.

Richard (L) with source hammer and Caleb wearing a steel plate neclace.

Caleb laying out receiver flags.

A rookie mistake unrolling the geophone cable.  It won't happen twice.
Packing up and Richard horse-collaring the cable, which Chris showed him how to do from experience in 1978 on a Western Geophysical crew.  Back then, horse-collaring was industrial practice.  With modern commercial systems having many thousands of channels, cables are too big to collar or the crew may be wireless and thus have no cables at all. But collaring is still a useful skill for near-surface seismic work.

Seismic Unix processing makefile

segyread tape=./49477.sgy \
| segyclean \
| suflip flip=2 \
| sushw key=gx a=1 c=1 j=1 \
| sushw key=offset a=1 c=1 j=1 \
surange <
segyread tape=./49479.sgy \
| segyclean \
| suflip flip=2 \
| sushw key=gx a=26 c=1 j=1 \
| sushw key=offset a=25 c=1 j=1 \
surange <
segyread tape=./49482b.sgy \
| segyclean \
| suflip flip=2 \
| sushw key=gx a=51 c=1 j=1 \
| sushw key=offset a=49 c=1 j=1 \
surange <
fcat >
surange <
sugain < tpow=1 epow=1 \
| suximage perc=99 \
 label1="Time (s)" label2="Offset (m)" \
 windowtitle="Shot oldmain1" &
sugain < pbal=1  epow=2 \
| supsimage perc=99 \
 label1="Time (s)" label2="Offset (m)" \
 title="Shot oldmain1" \
 d1s=.2 d2s=.2 \
 grid1=dot grid2=dot \
 d1num=.02 d2num=5 \
 curve=c1.txt,c2.txt npair=2,2 curvecolor=yellow,red \
 x1end=.3 \
> shot.eps
ps2pdf shot.eps 
sugain < pbal=1 \
| suphasevel fv=100 nv=200 dv=5 fmax=250 \
| suamp mode=real \
| supsimage style=normal \
 label1="Frequency (Hz)" label2="Phase Velocity (m/s)" \
 title="Shot oldmain1: Dispersion" \
 d1s=.2 d2s=.2 \
 grid1=dot grid2=dot \
 height=4 \
 d1num=20 d2num=100 \
> disper.eps
ps2pdf disper.eps