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Overlay indicating specific Earthquake Fault Subdividion Awareness, and was supplied for the purpose of the 2020 District PlanGrouping: - District Wide MatterSub Group: - Natural HazardLayer Shape file provided by: - Helen Jack, Senior Scientist, at Environment Canterbury - ECANDate that the Layer was provided: - 22nd of May 2020----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Metadata Description from the E-can - Suggested fault hazard (subdivision) overlay for the Timaru District Plan, May 2020.The suggested Timaru fault hazard (subdivision) overlay comprises all definite (well-expressed and moderately-expressed) and likely (well-expressed and moderately-expressed) fault awareness areas from the Canterbury fault awareness areas 2019 dataset, as recommended in Barrell, et al, 2015, Guidelines for using regional-scale earthquake fault information in Canterbury. GNS Science Consultancy Report 2014/211. It also includes small lengths of definite (not expressed) and likely (not expressed) fault awareness area where they link two definite (well-expressed or moderately-expressed) or likely (well-expressed or moderately-expressed) fault awareness areas, because the fault rupture hazard should still be considered in these areas during subdivision.These small lengths of definite (not expressed) and likely (not expressed) fault awareness area have had their width reduced to be the same as the definite (well-expressed or moderately-expressed) and likely (well-expressed or moderately-expressed) fault awareness areas on either side (total width 250 metres) as it is unlikely that the actual location of the fault trace deviates from the adjacent definite (well-expressed or moderately-expressed) and likely (well-expressed or moderately-expressed) fault awareness areas. See Barrell, et al, 2015, Guidelines for using regional-scale earthquake fault information in Canterbury. GNS Science Consultancy Report 2014/211and the metadata for the Canterbury fault awareness areas 2019 dataset for more detail on how the fault awareness areas were delineated.The fault awareness areas show areas where there may be a surface fault rupture hazard. Surface fault rupture is the permanent breaking, ripping, buckling or warping of the ground on or near the line where a fault meets the ground surface, as a result of movement on the fault. It is different from earthquake shaking.The suggested Timaru fault hazard (subdivision) overlay is where the fault rupture hazard should be specifically considered and the fault rupture deformation areas mapped as part of a subdivision consent.Descriptions of the attribute fields:Name: Fault name, taken from the district fault name field (e.g. TDC_name) in the district fault datasets. Some of these have been changed from the original district fault names to make them consistent with what is given in the district fault report.Zone: Fault zone that the fault is within, if any.Certainty: The level of confidence that the mapped feature is in fact an active earthquake fault - definite, likely or possible. See Barrell, et al, 2015 for full descriptions.Surface form: How clearly the mapped feature can be seen at the ground surface - well expressed, moderately expressed, not expressed or unknown. See Barrell, et al, 2015 for full descriptions.Min RI: Minimum fault recurrence interval, taken from the summary table of each district fault report.Max RI: Maximum fault recurrence interval, taken from the summary table of each district fault report.Min RI: Class:Minimum fault recurrence interval class (as defined in Kerr, et al, 2003, Guidelines for development of land on or close to active faults), taken from the summary table of each district fault report. Some values have been changed to better match the minimum fault recurrene interval.Max Ri: Class:Maximum fault recurrence interval class (as defined in Kerr, et al 2003, Guidelines for development of land on or close to active faults), taken from the summary table of each district fault report. Type: Whether the mapped feature is a fault (fault reaches the ground surface) or a monocline (fault stops below the ground surface but forms a fold in the ground surface).Other technical fields, such accuracy, sense of movement, dip direction, down quadrant, trendandfacing, as well as territorial authority (all Timaru) and buffer distance(all 125 metres) have been removed for simplicity but this information can be found in the Canterbury fault awareness areas 2019 dataset. |