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IRIS/PASSCAL Intern Caps Busy Summer with Alaska Deployment at Poker Flat

It's been a busy summer for IRIS/PASSCAL intern Kasey Aderhold, a PhD Candidate at the Department of Earth & Environment, Boston University. Kasey has been heavily involved in an ongoing comparison of seismic vaults to direct burial installations at two sites: the Dotson Ranch near Socorro, NM, and Poker Flat in Alaska. 


Here follow some photographs showing intern Aderhold getting some practical field experience during deployments at Dotson Ranch and at Poker Flat in the summer of 2013.



The Dotson Ranch deployment near San Antonio, NM was the focus of most of Kasey's work over the summer. A revised emplacement technique of putting broadband sensors directly into soil (aka direct burial) was being tested, with the first phase (fall 2011 to spring 2013) comparing data quality and sensor stability between the direct burial and the traditional 1m deep PASSCAL-style vault.

 Kasey, along with IRIS/PASSCAL's Associate Director/Operations Tim Parker and Helena Buurman (Postdoctoral Research Fellow, Geophysical Institute, University of Alaska Fairbanks), helped perform the servicing of the three Poker Flat Research Range direct burial stations and the installation of two new vault stations. This photograph shows the Poker Flat site on July 22, 2013, before servicing of the direct burials and installation of the vaults.(Click the image to see a larger version).





Helena Buurman of UAF used an auger to start a hole for one of the seismic vault installations.





This photograph shows Kasey excavating the hole for the new vault.





Here is Kasey making a final check on sensor position and cable connections.








Kasey documented the new vault installation.






This is an image of Kasey next to the solar panel at the conclusion of the deployment.

This photograph shows the Poker Flat site on July 26, 2013, after servicing of the direct burials and installation of the vaults. (Click the image to see a larger version).

This is a view looking towards North-NorthEast of the Poker Flat site on July 26, 2013. Direct burials are from left to right (PIC3, PIC2, and PIC1). The vaults from left to right are named Vault A and Vault B. All aluminum cable housing was covered with gravel; boxes were secured with straps and rocks.





While she enjoyed taking part in the Alaska deployment, most of Kasey's efforts over the summer were concentrated on analysis of the Dotson Ranch direct-burial versus seismic vault study results.  Kasey presented some intermediate results on the Dotson Ranch comparisons at a well-attended seminar she gave at PASSCAL during her last week there. 




At her seminar, Kasey discussed numerous figures of merit developed for the analysis.


This plot shows the Median Power Spectral Density for January 1st, 2012 through August 31st, 2012; Posthole data is for the interval March 13, 2012 through November 11, 2012. (Click the image to see a larger version).

The blue and cyan traces (cooler colors) represent the vaults, while the red and pink traces (warmer colors) show direct burials.  The green trace is the posthole sensor that was only installed for part of the interval (3/13/12-11/11/12).  The dashed traces are the BHE component, while dotted are BHN components and solid are BHZ components. NLNM and NHNM are the New Low Noise Model and New High Noise Model respectively.

PASSCAL thanks Kasey Aderhold for her many valuable contributions this summer, and wishes her the best in her future studies.