Regional and teleseismic events recorded across the TESZ during POLONAISE'97

Wilde-Piórko M; Grad M, Polonaise Working Group


314(1-3), 1999, 161-174, 10.1016/S0040-1951(99)00242-5

20 Polish short-period three-component stations were continuously operating for three weeks during POLONAISE'97 in the contact zone between Palaeozoic and Precambrian platforms in Poland. The distances between seismometers were about 20 km and the digitization interval was 0.02 s. Besides the shots, a few regional events from the Lubin area and teleseismic events mainly from the SE backazimuth were also recorded. Interpretation of traveltimes for P and S waves for regional events using a simplified LT-7 model of crustal structure for theoretical calculation allowed correction of their origin time. The same model can also explain the traveltime residuals of P waves for teleseismic events. The main features of the division of Poland into two platforms by the Teisseyre–Tornquist tectonic zone (TTZ) is seen both in the shape of residuals of teleseismic phases and in the receiver function. A passive seismic experiment made during POLONAISE'97 as a reconnaissance for future teleseismic tomography experiment TOR-2 gave quite promising results; however, to make a traveltime tomography and receiver function analysis, the duration of data acquisition should be about half a year.