Earthquakes and Water

Abstract

This paper describes the water level variations in wells YuZ-5 and E-1 in Kamchatka during the Zhupanovsky earthquake that occurred on January 30, 2016 (Mw=7.2, Н=180 km). The distances from the Zhupanovsky earthquake epicenter to wells E-1 and YuZ-5 were 70 and 80 km, respectively. In well YuZ-5, the water level raised by 9.4 cm during 45 minutes after the seismic wave arrival. This effect was caused by a combination of a co-seismic rise in the water level due to the volumetric compression of the water-bearing rocks during fracturing in the earthquake source and an impulse increase in the fluid pressure near the wellbore during the seismic shocks. We estimated the amplitude of the coseismic water level increase (h=7.3 cm) and the strain value resulting from the volumetric compression of the water-bearing rocks, which is consistent with the estimated value of the coseismic volumetric deformation in the area of the well at the depth of 500m: D1 = -4.510 -8 . This estimation was based on the model of the dislocation source in the homogeneous isotropic elastic half-space with the parameters of the Zhupanovsky earthquake focal mechanism. After the earthquake, the water level dropped for three months at an amplitude of about ~40 cm. In order to estimate the radius of the well sensitivity to the pressure drop source, we used the model of water level lowering that followed the pressure drop in the aquifer at a distance to the well as a result of the improved filtration properties of the water-bearing rocks after the seismic shocks. The estimated radius of the well sensitivity, R is 450 m. For 3.5 months before the Zhupanovsky earthquake, ~20 cm increase in the water level was observed, which is anomalous in comparison with the average seasonal variations of the water level, as shown by the long-term observations. In our opinion, such a rise in the water level occurred in the process of the earthquake preparation, and can thus be viewed as its precursor. In well E-1, a sequence of water level changes manifested a hydrogeodynamic precursor: the water level dropped at an increased rate for 21 days before the earthquake, and raised at an amplitude of 3.7 cm during one month after the earthquake. The hydrogeodynamic precursor detected in real time gave grounds for forecasting a highly probable strong earthquake at a distance of up to 350 km from wells E-1 within a month. This forecast was reported to the Kamchatka Branch of the Russian Expert Council (KB REC) on January 21, 2016. The Zhupanovsky earthquake occurred on January 30, 2016, and its magnitude, time and location correlated with the prediction. The case of this earthquake shows that the Kamchatka Branch of the Federal Research Center 'Geophysical Survey of RAS' has the system of water level observations and data processing, which is capable of diagnosing (close to real time and retrospectively) different types of hydrogeoseismic variations in the water level in wells in case of strong seismic events, and detecting the hydrogeodynamic precursors of strong earthquak...

Pore-water evolution and solute-transport mechanisms in Opalinus Clay at Mont Terri and Mont Russelin (Canton Jura, Switzerland)

“…Various authors characterised the hydrogeological consequences of such events (e.g. MuirWood and King 1993;Wang and Manga 2010). Fluid flow and geochemical disturbances have been observed over no longer than days to years.…”

Food, water, and fault lines: Remote sensing opportunities for earthquake-response management of agricultural water

“…There are a variety of earthquake mechanisms that can influence changes in hydrologic flows that include liquefaction and surface and subsurface flows (Montgomery andManga, 2003, Wang andManga, 2009). While any abrupt change in water delivery can threaten vegetative health, extent of crop damage depends on the type, magnitude, and duration of the temporary change.…”

Опыт Регистрации Вариаций Уровня И Физико-Химических Параметров Подземных Вод В Пьезометрических Скважинах, Вызванных Сильными Землетрясениями (На Примере Камчатки)

“…В настоящее время его разрешающая спо-собность составляет 1 мСм/м, что является недостаточным для уверенного выделения гидрогеосейсмических вариаций в изменениях электропроводности подземной воды. При регистрации вариаций уровня воды также желательно осуществлять измерения с частотой не менее 1-10 Гц, особенно во время прохождения сейсмических волн, как это обеспечивается за рубежом (в Японии, США, в Китае, Израиле и других странах) при проведении аналогичных наблюдений [Wang, Manga, 2010].…”

“…Ди-намическая деформация водовмещающих пород и сотрясения ствола скважины при прохождении сейсмических волн от сильных землетрясений также могут сопровож-даться разнообразными ко-и постсейсмическими эффектами в изменениях уровней и химического состава подземных вод. Описание таких эффектов приводится в много-численных работах, например в [Копылова, 2001, 2006Копылова и др., 1994;Wang, Manga, 2010]. При их изучении основное внимание исследователей уделяется объясне-нию гидрогеодинамических и гидрогеохимических процессов их формирования и об-щей оценке воздействия сильных землетрясений на состояние флюидонасыщенной геологической среды.…”

“…При проведении наблюдений в скважинах Камчатки и других сейсмоактивных ре-гионов особый научный и практический интерес представляют изменения в состоянии подземных вод, проявляющиеся перед сильными землетрясениями (или гидрогеологи-ческие предвестники), в связи с возможностью их использования для прогнозирования сильных землетрясений и уточнения времени таких событий [Копылова, 2001, 2006а,б, 2010Копылова, Болдина, 2012;Копылова и др., 1994;Wang, Manga, 2010].…”