Open AccessDetailed S‐wave structure in the Dublin Basin and its northern margin
Author(s) -
Murphy N. P.,
Jacob A. W. B.
Publication year - 1985
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1985.tb04340.x
Subject(s) - geology , precambrian , paleozoic , basement , seismology , seismic refraction , horizon , surface wave , shear (geology) , paleontology , carboniferous , structural basin , geophysics , geometry , computer science , telecommunications , civil engineering , mathematics , engineering
Summary. The seismic structure has been measured to a depth of about 3 km along a 30 km seismic profile in east central Ireland. This profile is unusual in that it is the S ‐wave velocity—depth structure that has been measured to a degree of precision more normally associated with P ‐wave results. One reason for this is that the sources used were quarry blasts which generated strong S ‐waves and short‐period surface waves but rather weak P ‐waves. The results show a layer of Carboniferous limestone with shear velocity 2.65 km −1 s overlying a layer with a velocity of 3.06 km s −1 . This second layer was interpreted as Lower Palaeozoic strata (Silurian/Ordovician) since this velocity was evident in an inlier seen at the surface at the northern end of the line. A third refraction horizon, shear velocity 3.45 km s −1 and displaying a basinal structure, was also recognized. This may be Cambrian or Precambrian basement.