The occurrence of seismic events in glaciers has been an issue in the scientific literature since the 1950s, following the report about icequakes in Baffin Island (Rothlisberger 1955). Targeted seismological studies were undertaken by the Polish Expedition to Spitsbergen in 1962. Most of research described in this book has been done by the author in the years 1970–2006, but not all the results have been available to international communities of seismologists and polar researchers, since some of them were published in Polish. Recently, the topic gains actuality in relation to intensified studies on climate changes and the observed growing activity of seismic glacial events.

In recent years, the glacier seismicity has been extensively studied in various regions of the globe. Research has been done on Alaska where an automated detection and event sifting routine was implemented (see, for instance, O’Neel et al. 2010; Mikesell et al. 2012). Studies were also made in the Swiss Alps (see, for instance, the paper by Faillettaz et al. (2011), reporting monitoring and measuring of icequake activity prior to the Weisshorn Glacier break-off), and in Greenland (see, e.g., the paper by Veitch and Nettles 2012, describing 121 glacial earthquakes occurring in the period 2006–2010), and in Antarctica (e.g., MacAyeal et al. 2008). Possible mechanisms of glacial earthquakes have also been widely discussed (e.g., Tsai et al. 2008).

The book describes an extensive study of seismic events associated with dynamics of the Hans Glacier in South Spitsbergen (see a photo in Fig. 1.1) as well as an analysis of a series of seismic events observed in Alpine glacier and in the Antarctic region. The study on the Hans Glacier is mainly based on the recordings from the Hornsund seismological station and measurements made by the author directly on the glacier. Research in the Antarctic region has been done at the Antarctic Peninsula area, West Antarctica.

Fig. 1.1
figure 1

View on part of the Hans Glacier, Hornsund Fiord, South Spitsbergen

Full size image

The results obtained until the mid-1997 have been summarized in the book: Seismicity of the Hornsund Region, Spitsbergen: Icequakes and Earthquakes (Górski 1997), and are briefly repeated here, together with new data and interpretation.

Since the Hornsund station of the Institute of Geophysics PAS has been playing a key role in the study of seismic glacial events, and was the site of the first targeted recordings in 1962 (Lewandowska and Teisseyre 1964), its brief history is described in Chap. 2. The station, along with the whole Hornsund Fiord, was declared in 2002 as one of the European biodiversity flagship sites. The station is used by many scientific institutions for realizing research projects in South Spitsbergen. Another Polish station in Hornsund area, localized in its western part, in the vicinity of Werenskiold Glacier, was established by the University of Wrocław in 1971. In addition to the Hornsund region, Polish academic institutions do systematic studies using the following two stations: the one in the Kaffiøyra, NW Spitsbergen, belonging to the Nicolaus Copernicus University in Toruń, and the other in Bellsund, West Spitsbergen, operated by the Maria Curie-Skłodowska University in Lublin. The area of the first of these stations, in Kaffiøyra (Coffee Plain), has already been the site of the Polish Glaciological Expedition in 1938 (Grześ and Sobota 2005). The results of the first Polish Glaciological Expedition to Oscar II Land in 1938 were so interesting that further complex environment studies were undertaken in 1975. They have been conducted at the already existing station as well as at the Polar Station of the Nicolas Copernicus University. The expeditions to this station were for many years organized and led by Professor Marek Grześ. This station is certainly the most northerly exposed Polish scientific facility. Polish scientists have also been using Norwegian bases and traper huts located in other regions of Spitsbergen, kindly made available to them.

In Chap. 3 it is described how the two categories of seismic events were distinguished and how they are related to dynamic processes within the glacier. These are the icequake- and icevibration-type events (the distinction made by the author). The icequakes are associated with the velocity gradient of the ice flow in the marginal zone of the glacier; an analysis is made of the ice flow velocity changes in time. The icevibration-type events may be related to glaciodynamical processes occurring in the main stream of the glacier. Of importance are also resonant vibrations of large elements of the glacier.

In Chaps. 4–6 the results of a few seasonal recordings of icequakes in the ablation zone of the Hans Glacier are outlined. The measured seismic wave velocities in the studied glacier part are given. Zones of icequake-type activity are delineated, and focal parameters of these events are calculated using spectral analysis. A comparison was made of focal parameters of icequakes with focal parameters of weak tectonic earthquakes and mining tremors, calculated using the same method. The calculatons were made with the help of original programs developed at the Institute of Geophysics PAS.

In Chap. 7 a comparison is made of icevibration-type events from various-type glaciers. Three-dimensional spectral analysis is presented and a relation of the dominant frequency with the glacier size is demonstrated.

Chapter 8 presents an application of the shear-band model to the determination of focal parameters. An attempt was made to estimate the thickness of foci on the basis of shear-band model (Teisseyre 1996) for icequakes recorded on the Hans Glacier (Chap. 6).

It is worth noting that the activity of Polish explorers of Polar regions, both the Arctic and the Antarctic, has a very long history. As concerns the bibliography of the Spitsbergen region, the reader is referred to two comprehensive volumes: Bibliography of Polish Research in Spitsbergen Archipelago, Part I, years 1932–1996 (Zalewski 2000) and Bibliography of Polish Research in Spitsbergen Archipelago, Part II, years 1997–2006 (Giżejewski 2010).

In the years following the period covered by the above-mentioned bibliographies, Polish scientists were active in numerous studies of Spitsbergen glaciers, also those carried out on a large scale in the framework of various international programs, notably within the Fourth International Polar Year 2007–2009. At present, the Institute of Geophysics PAS participates, e.g., in the following projects: SvalGlac (2010–2013), aiming at the Svalbard glaciers evolution model under climate change conditions, Ice2sea (2009–2013) estimating the future contribution of continental ice to sea-level rise, and SIOS-PP—Svalbard Integrated Arctic Earth Observing System.

Of great importance in recognizing the Polar regions are also geodynamical surveys. The Laboratory of Experimental Seismology of the Institute of Geophysics has been carrying out numerous studies in these regions. In particular, between 1976 and 2006 there were five seismic expeditions to Svalbard and five expeditions to West Antarctica. In Svalbard, deep crustal seismic refraction and wide-angle reflection surveys were made along several profiles of a total length of about 2,500 km. In West Antarctica, seismic measurements were performed along a number of profiles of a total length of about 4,000 km. During the Fourth International Polar Year 2007–2009, DSS seismic studies of the crust and upper mantle in Arctic and Antarctic regions were done in the framework of the IPY Cluster program 77: Plate Tectonics and Polar Gateways (PLATES and GATES), in a wide international cooperation. Some papers resulting from the Institute’s participation in geodynamic surveys in the Arctic and Antarctic are quoted in Chap. 7.

A new large international deep seismic sounding project, based on ocean bottom seismometer (OBS) measurements, is planned to begin in the years 2014–2015 in the region of Svalbard. In later years it will be continued in the Antarctic.