Concepts prevailing among the Polish geoscientists during the last decades assumed that the Teisseyre-Tornquist Zone is a major tectonic discontinuity separating the pre-Ediacaran East European Craton (EEC) crust from the Paleozoic Platform composed of terranes accreted during the Caledonian and Variscan orogenic processes. The recent interpretations of the TTZ by Mazur and collaborators, basedon gravity modelling and new PolandSPAN seismic reflection data, revive earlier ideas of the EEC crust extending to the western Poland and NE Germany. These authors propose that the TTZ is in fact a Sveconorwegian (ca. 1 Ga old) collisional suture marked by a crustal keel expressed as the Pomeranian and Kuiavian gravity lows in northern and central Poland. However, the present review of seismic data available, as well as a closer evaluation of the modelling results, do not confirm the keel/suture concept. On the other hand, the idea of the TTZ as an Early Paleozoic tectonic discontinuity is supported by several lines of evidence, including a strong regional magnetic gradient and a contrast in the crustal structure. The latter is revealed by seismic velocity distribution from the refraction data, in the results of magnetotelluric profiling and in recent seismicity patterns. The interpretation of the PolandSPAN data attempting to prove the continuity of the cratonic crust and its Ediacaran-Lower Paleozoic cover across the TTZ appears questionable. At the same time the POLCRUST-01 deep seismic profile in SE Poland documents that the zone is associated with the subvertical Tomaszów Fault. The basement top displacement by ca. 0,5 km and associated change in its slope are related to the fault whose deep crustal roots are further documented by reflectivity patterns in the lower crust. The recent modelling exercise by Krzywiec and collaborators aimed at questioning the thick-skinned nature of this fault does not present compelling results, being based on a poorly constrained geological model. The general conclusion from the present review is that the recently published data either support or at least do not contradict the concept of the TTZ as a tectonic zone separating the continuous EEC crust from several allochtonous blocks - mostly proximal Early Paleozoic terranes to the south-west. Thelithospheric memory of the TTZ echoed in successive stages of its reactivation in different intra-plate tectonic regimes - transpressive Variscan, mostly extensional or transtensional Permian through Early Cretaceous, compressional Late Cretaceous and finally Neogene, related to the Carpathian orogenic compression.
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W artykule przypomniano znaczenie rozpoznania stanu górotworu oraz wpływu zmian takiego stanu na bezpieczeństwo w rejonach eksploatacyjnych. Scharakteryzowano iskrobezpieczną przenośną aparaturę sejsmiczną PASAT M. Omówiono różne możliwości i sposoby wykorzystania aparatury w kopalniach węgla kamiennego, soli, rud miedzi do prześwietlania sejsmicznego między wyrobiskami i otworami, a także do profilowania sejsmicznego podłużnego w wyrobiskach górniczych, do sondowania sejsmicznego oraz do badania górotworu na okoliczność występowania utajonych zbiorników metanu, a także innych gazów.
EN
The article pointed out to the importance of identifying the condition of the rock mass and the impact of such changes on the state of security in the areas of mining. The intrinsically safe portable seismic equipment PASAT M was characterized Various possibilities and ways of how to use equipment in underground coal, salt, copper ore mines were discussed for seismic scanning between workings and holes, as well as for longitudinal seismic profiling in mine workings, for seismic probing and to study the rockmass with the view of the occurrence of the presence of latent reservoirs of methane and other gases.
Przedstawiono przykład zastosowania pomiaru prędkości fal akustycznych w terenie do wyznaczania modułu odkształcenia postaciowego G0 w prekonsolidowanych gruntach spoistych. Opisano metodykę oraz wyniki badań terenowych, które wskazują na potrzebę uwiarygodnienia metod pomiaru in situ badaniami laboratoryjnymi.
EN
The paper presents example of in situ measurements of seismic wave velocity for determination of shear modulus G0 in overconsolidated cohesive soils. In situ measurements of seismic wave velocity performed at Stegny test site were described. An analysis of seismic cone penetration tests results indicates that existing formulae for G0 evaluation play regional role and have to be applied for each kind of soil and subsoil stress history.
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