Paper

Deepwater Horizon

LIGO Sites Detect the Deepwater Horizon Explosion

Mike Fetsko and Lexi Bach

08/09/2017

Abstract

The research question that we tried to answer was to determine if there was evidence for the Deepwater Horizon explosion in the Gulf of Mexico on April 20, 2010 at 9:59 PM.  We were able to find evidence for seismic activity in the 0.3 to 1.0 Hz frequency band in the Livingston LIGO detector at that time and not in the Hanford band for that same time.  This makes sense since the explosion occurred in the water and may have dissipated by the time it reached Washington state.

Introduction

On April 20, 2010 in the Gulf of Mexico the Deepwater Horizon oil platform exploded at 9:56 CDT.  The platform was approximately 200 miles from the LIGO Livingston facility.  The explosion was sufficient enough to destroy the platform over the course of the next two days.  Our question was to determine if the explosion was detected in Livingston and in what frequency range.  We also looked to see if there was any activity displayed at the Hanford facility in Washington. 

Procedures

We initially researched the Deepwater Horizon event and determined its location relative to Livingston and recorded the time of the explosion in GMT so that we could explore the correct graph ranges for the LIGO Data. Next, we created graphs that overlayed the X and Y arms of the Livingston LIGO and explored the different frequency ranges for the different directional sensors to see if there was a significant spike at the anticipated time. We determined that the most significant spike occured in the 0.3 -1 Hz frequency range. The second most significant spike occured at the 1-3 Hz range. Additionally, we looked at the Hanford data for both arms and all frequency ranges to determine if that LIGO facility registered the event. 

Results

As seen in the plots below, all three directional sensors, in both the EX and EY arms, show seismic activity at around 3:00 GMT for the 0.3 to 1Hz range. The 0.3 to 1 Hz range is associated with "small, shallow, nearby earthquakes". Additionally, the 1-3 Hz range also shows seismic activity. This range is associated with "Small, shallow, and nearby earthquakes" as well. The 0.1 to 0.3 Hz range showed no significant seismic activity. This range is associated with "large, distant quakes". 

 

Figures

Figure 1. This shows both arms of Livingston with the X direction sensor, 0.3-1.0 Hz band

Figure 2. This shows both arms of Livingston with the Y direction sensor, 0.3-1.0 Hz band

Figure 3. This shows both arms of Livingston with the Z direction sensor, 0.3-1.0 Hz band

Figure 4. This shows both arms of Livingston with the X direction sensor, 1.0-3.0 Hz band

Figure 5. This shows that the Hanford LIGO center did not register the Deepwater Horizon explosion.

Figure 6. This shows both arms of Livingston with the X direction sensor, 0.1-0.3 Hz range.

Discussion and Conclusions

Given that the explosion occured in relatively shallow ocean water approximately 200 miles from Livingston, the "small, shallow, nearby earthquake" readings at LIGO correspond with the explosion in time and expected seismic activity. 

Additionally, the lack of seismic activity shown in the Hanford plot, also corresponds with the relative magnitude of this event. 

As seen in the plots, there is a second spike at approximately 4:00 am GMT. After extensive research on USGS and various news sources, we have found nothing of note that could cause seismic activity of this size. 

Bibliography