Earthquake Ground Shaking - Waikato Region

Purpose: This data has been published to support the Waikato Regional Hazards Portal. This data is part of the Earthquakes and landslides theme. Statement: The data was derived using manual digitising from published 1:250,000 geological maps with additional interpretation and synthesis. The information presented in this layer and accompanying Client Report 33596B.10 (WRC Technical Document TR96/17 - Internal Document # 1719533) was developed by the Institute of Geological and Nuclear Sciences (now GNS) for Waikato Regional Council as a regional snapshot of Ground shaking susceptibility. Extract from Beanland, S., Drummond, G., Huber, P., Hull, A., and Townsend, T., 1996: Earthquake Hazard Analysis of Waikato Regional Council Area. Client Report 1996/3359B.10, Institute of Nuclear and Geological Sciences Limited, Lower Hutt. 4.1 Geological units and hazard zones Geological materials in the Environment Waikato Region have been classified and mapped into four units for this study. These units are used to define hazard zones. It is important to note that the data have been both compiled and digitised at 1:250,000 scale, unlike the active fault data which were compiled and digitised at 1:50,000 scale. The accuracy of the hazard zone boundaries is therefore much less than that of the fault locations. The four units, in order of decreasing hazards, are: UNIT A: Holocene (<10,000 yrs) fluvial, lake, fan and swamp deposits and near coastal estuarine and beach deposits. Commonly high in volcanic ash content. These deposits comprise unconsolidated, very soft to stiff intermixed peat, clay, silt, ash, sand and gravel. The groundwater table generally very high. May include liquefiable layers. Critical thickness of sediments 2-15m. MOST HAZARDOUS. Amplification of approximately two MMI units and/or settlement and liquefaction common. UNIT B: Quaternary (<2.5 Myr) fluvial and marine terrace deposits, lignite, dunes and, pumice alluvium and ignimbrite flows. Unsaturated, slightly weathered, unconsolidated gravel, ash and sand. QUITE HAZARDOUS. Amplification of approximately one MMI unit common. UNIT C: Tertiary (<75 Myr) sandstone, siltstone, mudstone, coal measures, limestone, and conglomerate. Includes volcanic rocks of various ages. Gravels dense to very dense. Rock strength weak to moderately strong. NOT VERY HAZARDOUS, except that fine grained rocks are particularly prone to slumping and land sliding, especially if saturated and/or denuded of vegetation cover. UNIT D: Basement rocks, (>75 Myr), greywacke (generally indurated, well bedded, sandstones and siltstones, moderately to highly deformed) and minor schist. Weak to very strong. LEAST HAZARDOUS. WRC Natural Hazard Information Hierarchy: 4. General information Information that is to be used for information purposes only, or as an initial indicator of where further investigation may be required. This information is NOT suitable for use at property scale, or for: regional policy development or regional scale studies/projects district planning property specific risk assessments resource or building consents decisions that concern personal or public safety the conduct of commercial business insurance purposes This information may be a draft, that is still subject to review, or indicative only. Waikato Regional Council recommends further investigation and using other applicable natural hazard data, if available, for property specific purposes. The information is generally based on national scale mapping, preliminary regional scale mapping, or susceptibility from other existing data (e.g. LiDAR data). Users should make sure they are using the most appropriate natural hazards data available. Data held by other organisations may be better suited for property scale use or may be more up to date. Before using any of the Waikato Regional Council natural hazard data at property scale or for subdivision development purposes please contact the Waikato Regional Council Regional Resilience team for guidance. Note that further information on resource consenting is available here. Intended Use Scale: Data should not be used at scales greater than 1:250,000 Data Use Limits: Positional accuracy is Low; 80% of well-known points located with +/- 250 m of actual position. Attribute accuracy is High. All polygons have a single attribute rating from A-D. The source maps were drafted in September 1996. The information was considered to be current at that time. Subsequent research is likely to have superceded this data. Research was undertaken up to 1996 by IGNS. Data aquisition from Manual digitising from published 1:250,000 geological maps with additional interpretation and synthesis. Reviewers at IGNS verified data after capture. This is the best available source information was used but data is generalised by virtue of its scale (1:250,000) and age (1960 up until 1993). Data should not be used at a scale beyond 1:250,000. The data are not suitable for and should not be used in place of detailed investigations into any particular engineering, town planning or infrastructure project. Data Specific Disclaimers: Any data sets or maps derived from this information (either published or unpublished) should comply with and contain the following disclaimer: ““This map has been prepared using data supplied by the Institute of Geological and Nuclear Sciences (GNS) under contract to Waikato Regional Council. Unless otherwise agreed in writing, all liability of the Institute to any party other than Waikato Regional Council in respect of the map is expressly excluded”. “The presence of a hazard zone on this map does not guarantee the existence of such a hazard, nor does the lack of information preclude the existence of a hazard or risk. Waikato Regional Council, while providing the information in good faith, accepts no responsibility for any loss, damage, injury, or loss in value of any person, property, service or otherwise resulting from hazards or knowledge of hazards in the Waikato Region.” “The information portrayed on this map at a scale of 1:250,000 is to be used for emergency management and/or evacuation purposes only and is not to be used for land use planning.” “The information contained in this data set and/or map is correct at the date of verification only. Date of verification is September 1996.” The standard Waikato Regional Council Disclaimer applies to this data “While Waikato Regional Council has exercised all reasonable skill and care in controlling the contents of this information, Waikato Regional Council accepts no liability in contract, tort or otherwise howsoever, for any loss, damage, injury or expense (whether direct, indirect or consequential) arising out of the provision of this information or its use by you.” WRC Metadata: See full metadata by searching for 'HAZARD.sdeadmin.EARTHQUAKE_GROUND_SHAKING' under HAZARDS - Regional Hazards Portal - GIS Layers Terms of Use: This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License. Should users wish to distribute or publish derivatives or modified versions of this data then they must seek a data use agreement through WRC first. See the Waikato Regional Hazards Portal Terms of use here Waikato Regional Hazards Portal - Terms of use | Waikato Regional Council.