At the invitation of Dr. Andrew Schaeffer (Geological Survey of Canada, Natural Resources Canada), Dr. François Lavoué (UGA) presented the PACIFIC work on the use of seismic signals generated by trains for passive seismic imaging and monitoring on May 5th, 2021. The presentation provided an overview of the activities carried out within the framework of both the PACIFIC and FaultScan EU-funded projects.

The presentation was attended by around 40 people. Technical questions revolved around the parameters controlling signal amplitude, and a more general debate took place on the merits of excluding signals generated by trains from "classic" ambient noise datasets, as is done for earthquakes.

Understanding Seismic Waves Generated by Train Traffic via Modeling: Implications for Seismic Imaging and Monitoring.

Trains are now recognized as powerful sources for seismic interferometry based on noise correlation, but the optimal use of these signals still requires a better understanding of their source mechanisms. Here, we present a simple approach for modeling train‐generated signals inspired by early work in the engineering community, assuming that seismic waves are emitted by sleepers regularly spaced along the railway and excited by passing train wheels. Our modeling reproduces well seismological observations of tremor‐like emergent signals and of their harmonic spectra. We illustrate how these spectra are modulated by wheel spacing, and how their high‐frequency content is controlled by the distribution of axle loads over the rail, which mainly depends on ground stiffness beneath the railway. This is summarized as a simple rule of thumb that predicts the frequency bands in which most of train‐radiated energy is expected, as a function of train speed and of axle distance within bogies. Furthermore, we identify two end‐member mechanisms—single stationary source versus single moving load—that explain two types of documented observations, characterized by different spectral signatures related to train speed and either wagon length or sleeper spacing. In view of using train‐generated signals for seismic applications, an important conclusion is that the frequency content of the signals is dominated by high‐frequency harmonics and not by fundamental modes of vibrations. Consequently, most train traffic worldwide is expected to generate signals with a significant high‐frequency content, in particular in the case of trains traveling at variable speeds that produce truly broadband signals. Proposing a framework for predicting train‐generated seismic wavefields over meters to kilometers distance from railways, this work paves the way for high‐resolution passive seismic imaging and monitoring at different scales with applications to near‐surface surveys (aquifers, civil engineering), natural resources exploration, and natural hazard studies (landslides, earthquakes, and volcanoes).

The accepted version and the supplementary material can be downloaded as a compressed file from this webpage.

The link to the published version is provided below as well.

Sometimes noise is incredibly helpful.

By Rahul Rao, Popular Science (January 28, 2021)

For the full article, please visit How trains can help scientists study what's underground | Popular Science (popsci.com)

Click here to download the press release (Pdf format) announcing the online event co-organised by INFACT, PACIFIC and the NHM on December 3-4, 2020.

Technique now possible due to improvements in lithium batteries which power monitoring equipment

Article in the Canadian press by Jeff Walters · CBC News · Posted: Jun 12, 2019 1:28 PM ET  https://www.cbc.ca/news/canada/thunder-bay/thunder-bay-pacific-new-exploration-1.5172168 

Download PACIFIC first press release (July 2018): PACIFIC first press release

 Charlie Beard's presentation can be viewed on the link https://www.youtube.com/watch?v=g_qdwQGHNhs 

Executive summary: The Winter School on Sustainable Mineral Exploration was jointly organized by two European projects—PACIFIC and INFACT. The event was held at the International Campus of Andalusia in Huelva, Spain, between the 9th and 12th March 2020. The Winter School was divided in 3 lecture sessions, 1 practical session, and 2 visits to mining sites. The main goal of this school was to present the techniques and knowledge on sustainable mineral exploration that have been developed within the INFACT and PACIFIC projects. The school targeted an audience of European master students, PhDs and post-doctoral researchers. A total of 40 students, including 15 from the University of Huelva, physically attended the school. An additional 13 students participated in parts of the school via video conference, since unfortunately due to travel restrictions stemming from the COVID-19 pandemic those 13 students were unable to attend in person. Videoconferencing was a last-minute adaptation made by the Winter School to allow for the participation of individuals under travel bans, quarantine, or other restrictions. Students (both physical and remote attendees) came from 13 countries. The results of the anonymous survey conducted at the end of the school reveal that the event was a success, despite the ongoing COVID-19 crisis.

Executive summary: This document describes the structure and contents of the public website set up for PACIFIC on 29th November 2018 with the URL http://www.pacific-h2020.eu and updated in August 2020 to give more visibility to the expected impact of the project on mineral exploration in Europe, and reflect changes in the consortium. The website is based on Responsive web design (RWD), which provides an optimal viewing and interaction experience — easy reading and navigation with a minimum of resizing, panning, and scrolling — across a wide range of devices (from desktop computer monitors to mobile phones).

On the PACIFIC public website, you can find information about the project objectives and results, the concept, work plan and expected impact, together with the list of participants, external advisors and projects identified for clustering opportunities. The website also acknowledges the financial support received under the European Union’s Horizon 2020 research and innovation programme with the EU emblem as well as a specific statement. This is visible at the bottom of every webpage.

Throughout the project the PACIFIC public website will become a major tool to present the project research outcomes to a wide audience with: links to scientific peer-reviewed publications, project documentation, public deliverables and press releases available for download. On-going activities will also be regularly updated and communicated through news and events.