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The severity of surficial liquefaction manifestation was significantly over-predicted for a large subset of case histories from relatively recent earthquakes that impacted the Canterbury region of New Zealand. Such over-predicts generally occurred for profiles having predominantly high fines-content (FC), high-plasticity soil strata. Herein, the liquefaction case histories from the Canterbury earthquakes are used to investigate the performances of three different manifestation severity index (MSI) models. The prevalence of high FC, high-plasticity strata in a profile is quantified through the soil behavior type index averaged over the upper 10 m of a profile ( I_c10). It is shown that for each MSI model (1) the threshold MSI value distinguishing cases with and without manifestation increases as I_c10increases and (2) the ability of the MSI to segregate cases with and without manifestation decreases with increasing I_c10. Additionally, probabilistic models are proposed for evaluating the severity of surficial liquefaction manifestation as a function of MSI and I_c10. The approaches presented in this study allow better interpretations of predictions made by existing MSI models, although their efficacy decreases at sites with high I_c10. An improved MSI model is ultimately needed that better accounts for the effects of high-FC, high-plasticity soils more directly. 

Earthquakes occurring over the past decade in the Canterbury region of New Zealand have resulted in liquefaction case-history data of unprecedented quantity. This provides the profession with a unique opportunity to advance the prediction of liquefaction occurrence and consequences. Toward that end, this article presents a curated dataset containing ∼15,000 cone-penetration-test-based liquefaction case histories compiled from three earthquakes in Canterbury. The compiled, post-processed data are presented in a dense array structure, allowing researchers to easily access and analyze a wealth of information pertinent to free-field liquefaction response (i.e. triggering and surface manifestation). Research opportunities using these data include, but are not limited to, the training or testing of new and existing liquefaction-prediction models. The many methods used to obtain and process the case-history data are detailed herein, as is the structure of the compiled digital file. Finally, recommendations for analyzing the data are outlined, including nuances and limitations that users should carefully consider. 

Earthquakes occurring over the last decade in the Canterbury region of New Zealand have resulted in liquefaction case-history data of unprecedented quantity. This provides the profession with a unique opportunity to advance the prediction of liquefaction occurrence and consequence. Towards that end, this study presents a curated dataset of approximately 15,000 CPT-based liquefaction case-histories compiled from three earthquakes in Canterbury. The compiled, post-processed data is presented in a dense array structure, allowing researchers to easily access and analyze a wealth of information pertinent to free-field liquefaction response (i.e., triggering and surface manifestation). Research opportunities using this data include, but are not limited to, the training or testing of new and existing liquefaction-prediction models. The many methods used to obtain and process the case-history data are detailed in an accompanying data paper, as is the structure of the compiled digital file. Recommendations for analyzing the data are also outlined therein, including nuances and limitations that users should carefully consider. Version 2 (this posting) supersedes Version 1 (doi:10.17603/ds2-ydfc-cd47). Updates include: (i) Quantification of PGA uncertainties (only median values were provided in Version 1); (ii) Addition of a python data frame to facilitate greater use (only a matlab data file was provided in Version 1); and (iii) removal of several redundant data points. 

The influence of the non-liquefied crust that overlies a liquefied deposit on the severity of surficial liquefaction manifestations has been noted for several decades. In 1985, Ishihara proposed a generalize relationship relating the thicknesses of the non-liquefied crust and of the liquefied stratum to the severity of surficial liquefaction manifestations. Although subsequent studies using data from multiple earthquakes give credence to Ishihara’s relationship, the implementation of the procedure is tenuous for all but the simplest of profiles. In an effort to overcome issues with implementing the Ishihara relationship, new procedures have been proposed for predicting the severity of surficial liquefaction manifestations. The efficacies of two of these procedures are currently being assessed in a study using unique case history data from the 2016, Mw5.7 Valentine’s Day earthquake that impacted Christchurch, New Zealand. Preliminary results from this study show that both procedures yield predictions that are in accord with field observations. However, the final results from the ongoing study are expected to more fully assess the efficacies of these procedures. 

The moment magnitude (Mw) 7.8 Kaikōura, New Zealand, earthquake triggered relatively few cases of liquefaction and related phenomena (e.g., lateral spreading) despite the large magnitude of the event. Cases of severe liquefaction manifestation were confined to localized areas proximal to waterways near the township of Blenheim, in the north-eastern corner of the South Island of New Zealand. The occurrence and non-occurrence of liquefaction within the wider Blenheim area is shown to closely correspond with fluvial geomorphology and associated depositional setting of the sediments. Herein, the distribution of liquefaction within the region is detailed in the context of the geomorphological influences and sedimentologic controls. This work highlights the influence of geomorphic variability on the occurrence of liquefaction, with the aim of improving the assessment of liquefaction hazards for future events worldwide.