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Estimates of the onset times of P phases from active source experiments can effectively be used in developing wavespeed models, and the large number of recordings typical of such experiments incentivizes the development of automated approaches to generate these estimates. The simplicity and repeatability of an airgun source such as that used in the 2016 Pisagua/Iquique Crustal Tomography to Understand the Region of the Earthquake Source (PICTURES) project in northern Chile suggested that a straightforward application of waveform cross-correlation would suffice for arrivals recorded by a network of inland seismic stations, but did not work well due to significant variations in waveform morphology. For similar reasons, the machine learning application PhaseNet also did not work well. Application of an alternative algorithm typically used in passive source investigations that is indifferent to waveform morphology, the Regressive ESTimator (REST) autopicking package, also proved unsatisfactory, largely because the limited spectral bandwidth of the airgun source and the frequent occurrence of local seismicity led to numerous false picks. This motivated the development of a new approach, named CORREL, that is a hybrid of REST and cross-correlation, with the addition of a constraint in the form of a polynomial function based on the REST picks that provides a reasonable prediction of an onset time. Compared to the results obtained originally from REST and simple waveform correlation, the application of CORREL to the PICTURES data both significantly increased the number of arrivals estimated and greatly reduced the number of outliers. The combination of techniques retains the precision afforded by cross correlation while taking advantage of the accuracy afforded by absolute time picking. The predictive polynomial also provides CORREL a better means to discriminate true shots from the abundant natural seismicity. [ABSTRACT FROM AUTHOR]

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The following work analyzes the subjective dimension of vulnerability-ability of families that have been displaced by an earthquake in Chile. A qualitative design was selected, which included a theoretical sample, ten female heads of household and three institutional agents linked to the displacement and reconstruction of homes after the disaster. The data is produced by episodic interviews that use coding as an analytical strategy based on the grounded theory. The first result shows differences in the meanings assigned to displacement by the institutions that respond to disasters and the relocated families. At the institutional level, the predominant perspective was one based on instrumental reasoning about inhabiting, which reduced this concept to the facilitation of survival and the mere topographical occupation of a physical-material space. Meanwhile, for the relocated families, living in a camp meant an intensification of an "experience of continual vulnerability", which signified they were in a "no place" of circumstantial transit. As part of the second results, four family abilities were identified that did not subvert the social and structural vulnerability present but did enable the emergence of four configurations of tactics of agency and resistance in confronting disasters: resignation, individualism, concealment and solidarity. The conclusions highlight the importance of integrating a subjective dimension of vulnerability-ability in confronting the process of environmental displacement in order to guide the processes of relocation and psycho-social interventions sustained in a multidimensional perspective of inhabiting. [ABSTRACT FROM AUTHOR]