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Geographic coverage: The Kapiti Coast region of New Zealand, from Pukerua Bay to Otaki. 

This report assesses the potential for earthquake-induced ground shaking across the Kapiti Coast region. It identifies three hazard zones—Zone 1, Zone 2, and Zone 3-4—based on geological characteristics and seismic response. Zone 1 includes hill country underlain by strong bedrock and is expected to experience the least shaking. Zone 2 consists of compact gravel and sand from the Pleistocene era and represents moderate shaking potential. Zone 3-4 covers coastal areas with loose, young sediments such as beach sand and peat, which are more likely to amplify earthquake shaking. 
 
Two earthquake scenarios were considered: a distant moderate-to-large earthquake and a large local Wellington fault earthquake. For the distant event, Zone 1 would experience Modified Mercalli (MM) intensity V-VI (5-6), Zone 2 would experience MM VI (6), and Zone 3-4 would experience MM VI-VII (6-7). For the local event, shaking intensities could range from MM VII (7) to MM X (10) depending on proximity to the fault and local ground conditions. 
 
The report highlights that local geology significantly influences shaking intensity, with softer, younger sediments amplifying ground motion more than compact or bedrock materials. It also notes that while Kapiti Coast lacks extensive areas of thick soft soils found in other regions like Wellington or Lower Hutt, certain coastal areas may still pose higher risks. 
 
Recommendations include further geological mapping, seismic instrumentation, and analysis of historical earthquake data to refine hazard assessments. The report concludes that understanding and mapping ground shaking hazards can inform land-use planning and reduce earthquake-related risks in the Kapiti Coast region.