Well I have become the lucky guy who gets to utilize this new rotational seismometer. Ultimately this new instrument is supposed to be better than the typical geophone. Normal geophones are only 3 component sensors and the rotational seismometer is a 6 component sensor. It takes the Linear X,Y,Z, and rotations about these axes. The goal is that this method has better shallow surface results than your typical survey. I will be analyzing Rayleigh waves as well as Love waves in this survey at the FACT site in Albuquerque, New Mexico. Hopefully this new method will yield significantly better results!
So Im back at it and time is winding down. So what do you do when time is ticking, well simply be clutch. Here we are less than two weeks left with no days off no time to waste. So I said we were heading in a different direction now and RoMi is a word to remember. It might sound wierd now just wait until about a year or two and it will be popular like MJ and everybody knows MJ wether is Michael Jackson or Michael Jordan. We not only found a better method than the present one, but there is still endless ways to improve this sensor. Sensor improvement leaves us wondering just how great RoMi can be in the future of Surface Wave Analyses. Just to inform you all RoMi is a modified method of ReMi. ReMi is Refraction Microtremor and RoMi is Rotational Microtremor. RoMi in a nutshell is, and no im not talking bout a nutshell like that thick Linux book, but it is simply ReMi processing using a rotational Seismometer. Now in all seriousness this week i have wrote my abstract and completed my poster thanks to the best mentors. Shoutout to Hunter Knox and Rob Abbott!!
Here goes a figure from the poster!!
July 15th-July26th: spent these weeks processing data from my survey conducted during previous weeks. I will say now i am pretty skilled in matlab and Computer Programs in Seismology(CPS). I Constructed several ReMi Plots and RoMi plots in matlab. After retrieving the plots, I constructed a script to determine the dispersion curves from the plots. Took me a while but now the process is flawless. I also had to work in Excel to transfer the info into the format needed for CPS. CPS is ran inside of the terminal and has various features for calculaing and plotting seismic related items. I used it to get a velocity models from the inversions of the dispersion curve. This week was critical for the results of my project. Pretty much the direction of my project was dependant on this processing, but oh I was not even worried. So friday came around...
Friday July 26th
We sat down Rob, Hunter, and I and discussed what we were seeing in these results. Turns out it was not what we were expecting. So back to the drawing board, atleast thats what you were thinking. Results turn the project into a new and better direction. Told you guys I aint got no worries. So we were able to interpret the pots in a new view, and we noticed something intriguing. Monday I was on a mission to do various test to decipher what we were observing, so stay tuned in for next blog!
Week 4 June 23-29th:
This week i spent quite some time trying to learn and figure out how to do dispersion curves in Computer Programs in Seismology (CPS). I also devised a plan for the field work i would be conducting in week 5 at the FACT site at Sandia National Labs. I planned out a three day survey using five meter spacing to test out the new ATA ARS-16 rotational seismometer. Since this was a brand new sensor that was originally made to be used with a reftek, we had some modifications to make. We wanted to use it with the geode system, so i had the task of making a cable that was compatable with the geode and the new ARS-16. At first I was like me make a cable,.. Yea right, but i did and it held up pretty well. We did a couple of test and made sure everything was ready for the next week and just hoped there were no set backs.
Week 5 June 30th - 4th of July:
Well its the big week atleast thats what we thought! Melody came up from socorro because she needed "help" . Hopefully yall get that if not oh well. Anyways melody came to assist with the fieldwork and we went through a number of different ideas for our survey to generate shear waves. First we tried a 6x6 wood block. That wouldve been great for a 5 shot survey, apparently wood and sledgehammers don't get along. Plan B lets try a railroad tie. It seemed to be a better option than the 6x6. Turns out its just a heavier object to tote around and it didn't even last longer than the 6x6. So after demolishing two of our sources we moved on to the vertical hits of our survey. Its a good things those cant go wrong or can they? Well that pretty much wrapped up day 1.
Well well well the day was saved, no more destroying blocks of wood. Honeywell showed up with there new prototype Shear-Wave Seismic Generator (SWSG) and the name was given by yours truly. This SWSG is a remote controlled, truck mounted source. It has capabilities to generate shear-waves with a left or right hammer motion. It was a very unique source that has some room for improvement before it makes a big splash in future surveys. If only we would have altered some variables on our side we might have recieved some unique data sets. It also turns out you can mess up vertical shots! we changed some variables and like magic we had some pretty darn good data.
What we planned on being our last day in the field, July 3rd, well lets just say tune in next blog! So today we were going out here to do some more hammer shots with different variable adjustment to the sensor and the computer system. We also were going to clean up our survey so that equipment wouldnt get damaged over the holiday weekend. Cleaning up is so fun in the desert!
Week 6 July 8th- 12th
Well back in the office proceesing data..... looks like we are back in the field, but hey when do things ever go perfectly. So we plan to go back out there for a day and a half. first day was a half day we analyzed and thought out what exactly we were going to and what we had tools for. So this new sensor didn't come with instructions as to how they designed it to be set out. We tried setting it on the ground, setting it on a metal plate, epoxying it to the plate, and finally we tried embedding it deep in the sand. So the instrument doesnt have any spikes so we attempted to make some, but couldn't find any to fit. We eventually found some that would be just enough to hold it steady before unloading the sand into the hole we dug. So now we brought out our new source a 6x6 wood blcok with a metal plate mounted on the end. And there we have it folks, shear-wave source and we didnt destroy the wood. SUCCESS. Hey atleast thats what we thought then I smashed the trigger cable while i was swinging the hammer like i was in the homerun derby! But all hope isnt lost we still have a few good data points from when we switched cables. if only i wasn't so strong or if only they made wireless triggers! However i also had to do the vertical hammers again, but this time i had help from a local Sandian intern Jason D. So it wasn't that bad. This week i spent allot of time learning how to do ReMi in Matlab and i wrote a ton of scripts to help process all of these seismic data files. after all the analyzing we were pretty satisfied with the data we retrieved from all of the surveys we carried out. tune in next blog for more.
Hello everyone, in my project i will be using a 3 component geophone, vertical geophone, and a new rotational seismometer as well as your typical seismic equipment. To help with the data processing I will be using matlab and computer programs in seismology to generate my results. This past week i was out in the field with melody and we conducted the seimic survey here in Albuquerque, NM. took us three days to collect all the data. So far things are not looking to great, so i hope they get better!
So far I have been reading alot of scholarly articles about seismic microtremor analysis, the FACT site, and the Nevada Test Site. My project changed upon my arrival and I will now be working with a new type of seismic technology, known as a rotational seismometer. Hopefully we have succes with this new tool and i will be doing al bunch of field work pretty soon. Next week and the following week I will be making two trips out to Las Vegas to work on the Nvada Test Site. we are installing some type of infrasound intsruments which detect pressure differences. I will also get to actually see them use the explosive in this test!
As far as my goals go, I wanted to do fieldwork for one. I also wanted to become familiar with Matlab, Unix, and any other program I may encounter. I know it takes years to become proficient, but I atleast want to know alittle bit more than the basics. I also want to learn more about the geoscience life working in a national lab versus in industry or academia. Creating networks is another goal I plan to accomplish, as well as having a successful project and learning as much as i possibly can.
This week I have learned alot about seismology that I previously did not know. Some of which I still do not know, but I feel like some of the materials will be very beneficial to my project. I enjoyed being able to work with Unix and Matlab a little before I head to my summer placement. I have also learned that hiking is not in my future, but golf may be.