Issues

Front: Stand-alone geophones have been used for decades within the active-source seismic community, but recent technological advances in geophone instrumentation have made it possible to use them for a wide range of passive seismic studies as well. The SRL Focus Section on Geophone Array Seismology (this issue) comprises 13 articles that present investigations into geophone instrumentation, active-source imaging and explosion physics, local seismicity and aftershocks monitoring, and receiver function and ambient noise imaging with dense arrays. Shown here are a deployment of nodal seismometers in Salt Lake City with seven collocated pairs of surface and buried nodes (red circles) with different gain settings (lower left, from Farrell et al., this issue); horizontal shake-table tests for a sensor (upper right, from Ringler et al., this issue); as well as a student preparing a hole for installation of a node (upper left) and students orienting a three-component 5 Hz node during installation at a gradiometer site (lower right), both from Sweet et al. (this issue).

Back: In 2016, students from the geology department at Leicester University used simple low-frequency geophones and low-cost seismic dataloggers set up in a primary school and a local museum to record crowd-induced vibrations at King Power Stadium, home of the Leicester City Football Club, a professional soccer team in the English Premier League. Clear signals were detected every time the home team scored a goal, which students dubbed “Vardyquakes” on social media after the team’s star striker, Jamie Vardy. After a student-led social media campaign, the story went viral in the mainstream media. Denton et al. (this issue) documents the project and notes that its real success was in finding an engaging and reliable tool for encouraging university students to participate in seismologyrelated outreach activities with younger local students and their community.