Massive landslide at Utah copper mine generates wealth of geophysical data

Abstract

On the evening of 10 April 2013 (MDT) a massive landslide occurred at the Bingham Canyon copper mine near Salt Lake City, Utah, USA. The northeastern wall of the 970-m-deep pit collapsed in two distinct episodes that were each sudden, lasting ~90 seconds, but separated in time by ~1.5 hours. In total, ~65 million cubic meters of material was deposited, making the cumulative event likely the largest non-volcanic landslide to have occurred in North America in modern times. Fortunately, there were no fatalities or injuries. Because of extensive geotechnical surveillance, mine operators were aware of the instability and had previously evacuated the area. The Bingham Canyon mine is located within a dense regional network of seismometers and infrasound sensors, making the 10 April landslide one of the best recorded in history. Seismograms show a complex mixture of short-and long-period energy that is visible throughout the network (6-400 km). Local magnitudes (M L) for the two slides, which are based on the amplitudes of short-period waves, were estimated at 2.5 and 2.4, while magnitudes based on the duration of seismic energy (m d) were much larger (>3.5). This magnitude discrepancy, and in particular the relative enhancement of longperiod energy, is characteristic of landslide seismic sources. Interestingly, in the six days following the landslide, 16 additional seismic events were detected and located in the mine area. Seismograms for these events have impulsive arrivals characteristic of tectonic earthquakes. Hence, it appears that in this case the common geological sequence of events was inverted: Instead of a large earthquake triggering landslides, it was a landslide that triggered several small earthquakes.

The role of initial coherence and path materials in the dynamics of three rock avalanche case histories

“…Very little material is left on the rupture surface in the source zone, and there does not appear to be any runup at the distal toe. Modified from Pankow et al (2014) In Fig. 10, it can be seen that two different types of debris are visible in the deposit.…”

Influence of geotechnical properties on the run-out process at Bingham canyon slope failure

“…The seismic records analysed by (Pankow et al, 2013) indicate that the slides had durations of about 90 s, in very close with the computations obtained herein. This happens because the particles sliding down the northeastern pit wall hit the north-western pit wall, reversing the movement and slowing the slide.…”

“…Based on previous results, the geotechnical parameters of both slides are identical as shown in Table 7. The parameters are based on past research by (Pankow et al, 2013). Both slides are of roughly similar mass.…”

What is law without people? A review of mining legislation and communities

“…While mining contributes fairly to the national economy, it is also responsible for individual and communities' sufferings (Kitula 2006;Curtis 2009). Mining unearths the highest debris and deformed landscape with lasting consequences on water, air and land than any primary activity known (Pankwo et al 2014;Charbonnier 2001). It is also responsible for common respiratory diseases in historic mining communities (Centre for Environmental Rights 2013; Swart 2003).…”