Fiber Optics for Environmental Sense-Ing (Foresee) at Pennsylvania State University

Session: Photonic Seismology
Type: Oral
Date: 4/30/2020
Time: 09:30 AM
Room: 215 + 220
Description: 

We describe the Fiber-Optic foR Environmental SEnsEing (FORESEE) project at Pennsylvania State University, the first continuous monitoring distributed acoustic sensing (DAS) array in the Eastern US. This array is made up of nearly 5 km of pre-existing dark telecommunications fiber underneath the Pennsylvania State University Campus. The campus sits in the Allegheny Mountain region of the US, and our aim is to understand urban hydrology and detection of geohazards (particularly karst features). Here we detail the FORESEE experiment setup, fiber calibration and observations of natural events and anthropogenic activities in the first year. We calibrate the DAS measurement using M8.0 Peru earthquake data by a nearby seismometer and active-source geophone data. The observation of the S-wave reversal-polarity in the zigzag array is explained by the directionality of S-wave using the plane wave simulation. We observe a wide variety of seismic sources: natural events (earthquakes and thunderstorms), mining blasts, vehicles, music concerts and walking steps. We observe clear recordings of ground motions due to thunder not observed on previous dark fiber arrays. These thunderquake signals could be an important source of broadband energy for seismic imaging in an area with little earthquake seismicity. Further, we show preliminary results towards near-surface imaging with ambient noise interferometry, which requires careful preprocessing in the presence of anthropogenic noise, which builds further evidence that dark fiber can be a useful tool for seismology in cities.

Presenting Author: Tieyuan Zhu

Authors