Southland Liquefaction Risk (2006/2012)

The awareness of liquefaction has increased markedly since the Christchurch earthquakes.  It is basically an earthquake related process of turning a solid soil into a liquid and weaker state.  It is most likely to occur in saturated sands and silts.Related to liquefaction is a process called lateral spreading, whereby land moves towards lower areas whilst in a semi liquid state.The Southland areas considered most susceptible to liquefaction include low lying areas of hydraulic fill, peat mires, low lying parts of lake deltas and around the margins of the fjords.  The last two magnitude 7+ earthquakes (22 August 2003 and 15 July 2009) resulted in isolated pockets of liquefaction.Reports:Amplified ground shaking and liquefaction susceptibility, Invercargill City - January 2012 (PDF, 2.3MB)Geological hazards – Southland District Council Lifelines Study - July 2006 (PDF, 5.8MB)Note:  The methodology that was used in these reports may not hold today after knowledge gained from the Christchurch earthquakes and how that may relate to underlying assumptions regarding Southland.    This data was captured at a scale of 1:250,000 (boundaries are indicative).

Data and Resources

Additional Info

Field Value
Theme ["geospatial"]
Author Environment Southland
Maintainer EnvironmentSouthlandGIS
Source https://data-esgis.opendata.arcgis.com/datasets/37d15c4ef0774c9b8f637f54bbbdb3fa_11
Created 2019-08-27T02:46:16.000Z
Date modified 2020-08-26T20:27:24.000Z
Language English
Spatial {"type": "Polygon", "coordinates": [[[166.2614, -47.2241], [169.4078, -47.2241], [169.4078, -44.2884], [166.2614, -44.2884], [166.2614, -47.2241]]]}
Source Identifier https://data-esgis.opendata.arcgis.com/datasets/37d15c4ef0774c9b8f637f54bbbdb3fa_11
Record created November 11, 2020, Last Updated November 11, 2020