Abstract
article size, organic content, loss on ignition (LOI), geochemistry, radiocarbon and 137Cs analyses were carried out on paired cores taken from Wainui, Totaranui and Awaroa Inlets, Abel Tasman National Park. A 1700 year record of long- and short-term environmental changes was produced representing a sedimentary and geochemical sequence from tidal flat to mature salt marsh. The sequence is punctuated by a series of short-term environmental changes, namely tsunami, establishment of salt marsh, and European settlement. Long-term environmental changes include fluctuating accretion rates and relative sea level rise. Tsunami “signatures” include: (i) a peak in fines, (ii) contemporaneous or “delayed” peak in organic content and/or LOI, (iii) contemporaneous peaks in Fe and/or S, (iv) dilution of anthropogenic contaminants, and (v) visible change in the sediments. Ruptures of the Wellington and West Wairarapa Faults are considered to be the tsunamigenic sources. Pre-European sediment accretion rates in Abel Tasman National Park range from 0.5 to 1.7 mm/a, with post-European settlement rates increasing to 1.6–2.7 mm/a. In the past 30 years, rates have increased to 2.3–3.3 mm/a. The component of relative sea level rise is estimated to be about 1.3–2.2 mm/a which compares favourably with the nearest tidal records from Wellington.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call