Pleistocene marine terraces in new zealand

Abstract

Since the 1950s, the study of marine terraces in New Zealand has undergone a major change in emphasis. From studies focussing on altimetric correlations with the (then) standard Mediterranean sequence, and constrained by the four-glaciation model, there has been a change to greater appreciation of tectonic deformation, increasing use of numerical-age dating methods, and acceptance of the New Guinea sea-level record (augmented with oxygen isotope records in deep-sea cores), as a global standard. Shoreline datums are defined and discussed following the recommendations of Gage in 1953. Dating techniques as well as methods of regional and international correlation are reviewed. It is recommended that strandline age be used for reporting the age of marine terraces. The assignment of marine terrace ages based solely on height spacings is reviewed and found to be unreliable in the absence of other dating methods. Estimates of uplift rates based on marine terraces of last interglacial age are presented. Although there are an increasing number of potential dating techniques available that yield numerical ages, only a few of these (e.g., fission-track, amino-acid racemisation, uranium series) have so far been used for dating marine terraces in New Zealand. It is recommended that future research be directed towards detailed field mapping and greater use ofnumerical-age dating methods. Show more