Plugged Wells and Reduced Injection Lower Induced Earthquake Rates in Oklahoma

Difference between pre-plug back and post-plug back depth for wells that were initially injecting into the Precambrian basement or lower Arbuckle. Inset shows the location of these plugged back wells (colored triangles) and other disposal wells (grey triangles) within area of interest. Inset cross-section shows schematic of a disposal well that was plugged back out of the lowermost portion of the Arbuckle. | Skoumal et al. (2024) TSR

13 November 2024–Wastewater injection resulting from oil and gas production in Oklahoma caused a dramatic rise in seismic activity in the state between 2009 and 2015. But regulatory efforts to backfill some injection wells with cement and reduce injection volumes have been effective in lowering the state’s induced earthquake rate, … Continue Reading »

Strange Seismic Wave Arrivals Lead to Discovery of Overturned Slab in the Mediterranean

Map of seismic stations and the deep Granada earthquake. Red triangles indicate stations for studying the low velocity layer on the slab.

21 February 2024–Strange seismic wave arrivals from a 2010 earthquake under Spain were the clues that led to an unexpected discovery beneath the western Mediterranean: a subducted oceanic slab that has completely overturned. The waveforms paint a picture of a slab that descended rapidly into the Earth’s mantle and flipped … Continue Reading »

Q&A with TSR Editor-in-Chief Keith Koper

4 December 2023–As The Seismic Record nears its three-year anniversary, we asked Editor-in-Chief Keith Koper to talk about how the journal has evolved and what to expect next in its pages. SSA: The Seismic Record will celebrate its three-year anniversary in 2024. Why do you think the journal has been … Continue Reading »