| Popis: |
A 65 km seismic reflection transect was shot in 1998 across Mackenzie Basin to Mount Cook Village, South Island, New Zealand, to provide a detailed image of the crustal structure in the central Southern Alps. The first 5 s (two‐way time (TWT)) of data were processed separately, with a maximum offset of 14 km for each shot, to image the upper 12–15 km of the crust. Data were processed as one continuous section, although the line was physically segmented due to an area of relatively steep topography with no vehicular access. No major, continuous regional‐scale features > 10 km are present in the data, but numerous 2–3 km scale reflections and discontinuities occur which are consistent with the known geology of monotonous greywacke sequences overlying schist. Strong, well‐defined reflections mark the active Irishman Creek Fault and confirm it to be a southeasterly dipping reverse fault with c. 1300–1700 m of Late Cretaceous‐Pleistocene sediments preserved in the footwall and an uplifted greywacke ba... |
