Canterbury (New Zealand) CPTu soundings — curated Parquet for the conic library

Curated CPTu subset of the Canterbury, New Zealand, cone penetration test liquefaction case-history dataset (Geyin, Maurer, Bradley, Green & van Ballegooy, 2020), prepared as an analysis-ready Parquet file for the conic library. The source compiles CPT case histories from the 2010–2016 Canterbury earthquake sequence as a single structure array. The soundings carrying a piezocone pore-pressure record (u2) were selected — plain cones without u2 were excluded — and the measured per-depth fields (depth, tip resistance, sleeve friction, pore pressure u2) were exploded into one tabular file. The measured tip is the uncorrected qc and is kept as such. Cleaning steps: The synthetic pre-drill infill interval (depth below the pre-drill depth) was dropped Rows at exactly equal depth within a sounding collapsed by averaging the measurements Negative sleeve friction truncated to zero Rows with no usable cone reading dropped Soundings with source spikes/sentinels or shorter than 5 m removed. Because the source supplies neither density nor in-situ stresses, vertical stresses were derived: the soil unit weight was estimated per depth from the CPT via Robertson & Cabal (2010) and integrated down each profile to give the total stress (σv_tot). The pore pressure u0 is hydrostatic from the groundwater table, taken as the mean of the 2011 and 2016 event-specific water tables. A dense per-file key (Sorted ID) was assigned in chronological order while preserving the source identifier (Original ID); the test year (Year) is retained to disambiguate reused identifiers. The file is sorted by sounding and depth and stored as zstd-compressed Parquet. This curated derivative is released under the Open Data Commons Attribution License (ODC-By v1.0). Changes are limited to subsetting, exploding, cleaning, stress derivation, re-keying, and format conversion. Caveats: the reliability of the source u2 measurements is noted as unknown by the original authors (porous-stone saturation, etc.); the unit weight is correlated from the CPT, not measured, so σv_eff and any quantity normalized by it inherit that assumption; the cone area ratio is assumed as 0.80. Original dataset: Geyin, M., Maurer, B.W., Bradley, B.A., Green, R.A., van Ballegooy, S. (2020). CPT-Based Liquefaction Case Histories Resulting from the 2010–2016 Canterbury, New Zealand, Earthquakes: A Curated Digital Dataset (Version 2). DesignSafe-CI. https://doi.org/10.17603/ds2-tygh-ht91