caa a22 4500 606149171 CHVBK 20210128100532.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s00531-014-1110-x doi (NATIONALLICENCE)springer-10.1007/s00531-014-1110-x Initial seismic observations from a deep borehole drilled into the Canadian Shield in northeast Alberta [Elektronische Daten] [Judith Chan, Douglas Schmitt] The availability of a deep borehole in northeastern Alberta provides an unprecedented opportunity to study the in situ metamorphic craton rocks. This borehole reaches a depth of 2.4km, with 1.8km in the crystalline rocks, and is the only known borehole allowing access into the deeper rocks of the metamorphic Canadian Shield. In 2011, a zero-offset vertical seismic profile (VSP) was acquired to assist in the interpretation of seismic reflection data and geophysical logs. Three sets of upgoing tube waves interpreted from the raw profile correspond to the small-scale fluctuations in the borehole diameters and fracture zone in the crystalline rocks. A comparison between sonic log velocities and VSP velocities reveals a zone with increased velocity that could be due to the change in rock composition and texture in the basement rocks. The final processed profile is used to generate corridor stacks for differentiating between primary reflections and multiples in the seismic reflection profile. Analysis of the zero-offset VSP verifies existing log interpretation on the presence of fractures and the possible lithological changes in the metamorphic rocks of the Canadian Shield. The Author(s), 2014 Zero-offset VSP nationallicence Canadian Shield nationallicence Craton rocks nationallicence Metamorphic rocks nationallicence Velocity seismic profiling nationallicence Tube waves nationallicence Chan Judith Department of Physics, Institute for Geophysical Research, University of Alberta, 4-181 CCIS, T6G 2E1, Edmonton, AB, Canada aut Schmitt Douglas Department of Physics, Institute for Geophysical Research, University of Alberta, 4-181 CCIS, T6G 2E1, Edmonton, AB, Canada aut International Journal of Earth Sciences Springer Berlin Heidelberg 104/6(2015-09-01), 1549-1562 1437-3254 104:6<1549 2015 104 531 https://doi.org/10.1007/s00531-014-1110-x text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00531-014-1110-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Chan Judith Department of Physics, Institute for Geophysical Research, University of Alberta, 4-181 CCIS, T6G 2E1, Edmonton, AB, Canada aut NATIONALLICENCE 700 1- Schmitt Douglas Department of Physics, Institute for Geophysical Research, University of Alberta, 4-181 CCIS, T6G 2E1, Edmonton, AB, Canada aut NATIONALLICENCE 773 0- International Journal of Earth Sciences Springer Berlin Heidelberg 104/6(2015-09-01), 1549-1562 1437-3254 104:6<1549 2015 104 531