Study area
The Akatore Fault is the most seismically active area on the southeast
coast of New Zealand’s South Island (Figure 1). The onshore portion of
this fault has, in the past millennium, uplifted an approximately 30 km
of the coast by 2-3 meters above the high-tide zone (Litchfield and
Norris 2000). This amount of coastal uplift is reported to be sufficient
to eliminate intertidal species and potentially create empty habitats
for recolonization (Jaramillo et al. 2012; Hamling et al.2017). Radiocarbon dating at the Akatore fault line has constrained the
most recent rupture event to 800-1000 yr BP (Litchfield & Norris 2000;
Craw et al. 2020). Additional radiocarbon dating from sea caves
at the palaeo-hightide level similarly provided age estimates
<1000 years old, confirming direct relationships between
earthquake and coastal uplift (Craw et al. 2020; Parvizi et
al. 2020).