What Governs the Spatial and Temporal Distribution of Aftershocks in Mining‐Induced Seismicity: Insight into the Influence of Coseismic Static Stress Changes on Seismicity in Kiruna Mine, SwedenShow others and affiliations
2021 (English)In: Bulletin of The Seismological Society of America (BSSA), ISSN 0037-1106, E-ISSN 1943-3573, Vol. 111, no 1, p. 409-423Article in journal (Refereed) Published
Abstract [en]
Strong mining‐induced earthquakes are often followed by aftershocks, similar to natural earthquakes. Although the magnitudes of such in‐mine aftershocks are not high, they may pose a threat to mining infrastructure, production, and primarily, people working underground. The existing post‐earthquake mining procedures usually do not consider any aspects of the physics of the mainshock. This work aims to estimate the rate and distribution of aftershocks following mining‐induced seismic events by applying the rate‐and‐state model of fault friction, which is commonly used in natural earthquake studies. It was found that both the pre‐mainshock level of seismicity and the coseismic stress change following the mainshock rupture have strong effects on the aftershock sequence. For mining‐induced seismicity, however, we need to additionally account for the constantly changing stress state caused by the ongoing exploitation. Here, we attempt to model the aftershock sequence, its rate, and distribution of two M≈2 events in iron ore Kiruna mine, Sweden. We could appropriately estimate the aftershock sequence for one of the events because both the modeled rate and distribution of aftershocks matched the observed activity; however, the model underestimated the rate of aftershocks for the other event. The results of modeling showed that aftershocks following mining events occur in the areas of pre‐mainshock activity influenced by the positive coulomb stress changes, according to the model’s assumptions. However, we also noted that some additional process not incorporated in the rate‐and‐state model may influence the aftershock sequence. Nevertheless, this type of modeling is a good tool for evaluating the risk areas in mines following a strong seismic event.
Place, publisher, year, edition, pages
USA: Seismological Society of America (SSA) , 2021. Vol. 111, no 1, p. 409-423
Keywords [en]
induced seismicity, mining, Kiruna Mine
National Category
Mineral and Mine Engineering
Research subject
Mining and Rock Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-81415DOI: 10.1785/0120200111ISI: 000614215300029Scopus ID: 2-s2.0-85100035349OAI: oai:DiVA.org:ltu-81415DiVA, id: diva2:1501131
Funder
Vinnova, 2016-0269European Regional Development Fund (ERDF), HOMING/2017-4/35
Note
Validerad;2021;Nivå 2;2021-02-08 (alebob);
Finansiär: Foundation for Polish Science, Polish National Agency for Academic Exchange (PPI/PZA/2019/1/00107/U/00001)
2020-11-162020-11-162021-03-22Bibliographically approved