Search

The Bucaramanga seismic nest has the highest concentration in volume of intermediate depth seismic events with light and moderate magnitudes (Mb > 4.8) worldwide. Despite the nest depth (Zhypo ≥ 100 km), these events play a crucial role in the seismic hazard assessment for several cities in northern South America (NoSAm), particularly those situated close to their epicenters. Moreover, these earthquakes are widely felt across the country, even hundreds of kilometers away from the nest. This paper assesses the performance of commonly used subduction intraslab Ground Motion Models (GMMs) in predicting the updated nest database gathered and processed by the Colombian Geological Survey. This analysis confirms the necessity of a partially non-ergodic ground motion model for estimating the spectral accelerations produced by Bucaramanga nest earthquakes in northern South America. The GMM presented herein is the first model developed specifically for seismic nests in the region and is conceived as a regionalization of the recent NGA-Sub Abrahamson and Gülerce (Earthq Spectra 38(4):2638−2681, 2022) GMM. Additionally, we provide estimates of the variance components at both the earthquake and station levels and compare the developed GMM with the spectral accelerations recorded for typical earthquakes, for the highest magnitude earthquake in the database, and for a recent Bucaramanga nest earthquake having a moment magnitude over 5. [ABSTRACT FROM AUTHOR]

Whereas in the Global North the energy transition narrative focuses on the idea of 'global sustainability', in the Global South it is increasingly connected to old and new challenges that derive from dependence on natural resource extractivism and rentierism. In vast regions of South America, for instance, fossil fuels extractivism and the idea of (post-)development are inextricable. On the one hand, capitalist modernisation, energy security, and even political stability hinge on domestic use of fossil fuels and the rent generated by their exports. On the other hand, the idea of ending extractivism, which is again topical in Latin America, invites policymakers to dream on post-development and the possibility of converging toward the 'green' energy transition. This contribution builds on insights from Ecuador and Colombia, as paradigmatic examples, to address the juncture triggered by the energy transition in the Global South. [ABSTRACT FROM AUTHOR]

Mental health is a key issue for populations affected by conflict. The evidence base on the mental health of internally displaced Colombians is undefined, as well as protective strategies utilised by this group. This systematic literature review aims to identify and assess the evidence base on the mental health of Colombian internally displaced persons (IDPs). Specific objectives are to examine (1) prevalence and incidence rates of common mental disorders (CMDs) amongst adult Colombian IDPs, (2) risk factors associated with CMDs amongst this group, and (3) coping strategies used by these displaced persons. A database search was conducted in May 2021. Included studies reported quantitative and/or qualitative mental health outcomes of CMDs, and/or coping strategies, among Colombian IDPs. The search yielded 34 articles. Study quality ranged from adequate to poor, with several containing serious shortcomings. PTSD prevalence ranged from 1.2%-97.3%, anxiety from 0.0%-60.0%, depression from 5.1%-100%, and problematic alcohol use from 8.0%-33.5%. Factors significantly associated with CMDs were inconsistent. Seeking social support and problem-solving strategies were the two most-commonly reported coping strategies. Associations between mental health and coping were largely unreported. As the evidence base is weak, there is a clear need for better quality research in this area. [ABSTRACT FROM AUTHOR]

The northwestern corner of South America presents a highly complex geodynamical setting including the convergence between South America, Nazca, and Caribbean plates; which also entails heterogeneity and complexity in the lithospheric structure. Here, we present depth‐migrated common‐conversion point (CCP) teleseismic receiver function profiles carried out using seismological data between 2011 and 2020 from the Colombian Geological Service, combined with some stations of observatories and international networks. These profiles provide better constraints on the lateral interpretation of the main lithospheric discontinuities in this region. We provide an updated crustal thickness map displaying some differences from previous studies, especially in the northernmost part of the cordilleran system. Our results also show some intracrustal features such as the regional detachment surface beneath the Eastern Cordillera and the presence of deep melt reservoirs under the Central Cordillera and the Paipa‐Iza complex in the Eastern Cordillera. We also discuss the lithospheric thickness and the potential existence of a highly hydrated and serpentinized mantle wedge under the forearc over the slab segment south of the Caldas tear. Furthermore, the CCP profiles further support the subduction system segmentation under northwestern South America, with at least five slab segments, two of them overlapping between ∼5.5 and ∼8°N, three belonging to the Nazca plate, and two having a Caribbean origin. The Bucaramanga nest appears to be linked to the interaction between the two northmost slab segments, while the Cauca cluster might be related to a slab dehydration process of a highly fractured zone. Plain Language Summary: The Colombian tectonic configuration is highly complex with the convergence of three major tectonic plates. Despite extensive recent studies in this region, some of the important tectonic features are still under discussion. In this study, we present cross‐section images of the lithospheric and upper mantle structure beneath Colombia, carrying out an analysis of teleseismic wave conversions corresponding to data collected between 2011 and 2020 by the Colombian Geological Service, volcanological and seismological observatories, and international stations. The results show that the crust is thinner than estimated in previous studies in the northernmost part of the Colombian cordillera system, and provide some material on intracrustal features and lithospheric thickness. Moreover, our images support other studies on the subduction system in this area, showing the presence of five slab segments on the Pacific side subducting beneath Colombia, including an overlapping segment between ∼5.5 and ∼8°N. The two densest seismic clusters, the Bucaramanga nest and the Cauca cluster, seem to be linked to the interaction of two plates at depth and the dehydration of a fractured slab zone, respectively. Key Points: Crustal thickness beneath northwestern South America with some significant changes from previous studiesWe observe five different slab segments under northwestern South AmericaRegional detachment surface under the Eastern Cordillera ranging between 10 and 30 km depth [ABSTRACT FROM AUTHOR]

Atmospheric deep convection in equatorial continental regions is not homogeneously distributed in space or time, primarily due to surface inhomogeneities such as elevated topography and coastlines. This is the case in northwestern South America, which has particularly complex topography which, together with its geographical location, is responsible for some of the most prominent precipitation features around the globe. Although some of these features have been previously investigated in detail, others have not yet been studied, and some not even documented in the literature. The diverse atmospheric convective activity that takes place in this region constitutes a natural laboratory that can provide important insights into fundamental questions relevant for global climate. We use seven years of infrared brightness temperature data in 30 min intervals from the GOES‐13 geostationary satellite to estimate the spatial, seasonal and diurnal distributions of deep convective events in this region. By doing so, we bring forward several relevant features, providing a starting point for future investigations. For example, we find that deep convective events have a bimodal seasonal distribution throughout most of the Colombian Orinoco and Amazon basins, where precipitation is known to have a unimodal distribution. Furthermore, deep convective events in this region tend to be comparable in size to those offshore the Colombian Pacific coast or over the Magdalena river valley, but with significantly shorter lifetimes. On the other hand, nocturnal convection dominates at several continental locations; one of these, the middle‐lower Magdalena river valley, has been previously identified as one of the most active lightning hotspots on Earth, but its convective mechanisms have not yet been fully investigated. Another such location worth investigating is the middle Magdalena river valley, which may have strong similarities with the Maracaibo Lake area. [ABSTRACT FROM AUTHOR]

Intimate partner violence (IPV) effects over a third of Latin American women and results in significant health, economic and social consequences. While theory suggests that increasing the status of women, in their homes and neighborhoods, should prevent IPV, little empirical work has tested this in South America, in particular examining neighborhood-level indicators. We conduct multilevel analysis to identify predictors of recent emotional and physical and/or sexual IPV within a longitudinal sample of 1312 low-income women living in northern Ecuador, near the Colombian border. Status indicators, measured at the household and neighborhood-level, included women's asset ownership, intra-household decision making, labor force participation, and education, age, and salary relative to male partner. Females' increasing participation in household decision-making (between time 1 and time 2) was associated with decreased risk of physical and/or sexual (AOR: 0.41, 95% CI: 0.21, 0.78) and emotional IPV (AOR: 0.57, 95% CI: 0.30, 1.06), although the latter was marginally significant. Increases in neighborhood-level decision-making was protective against emotional IPV (AOR: 0.78, 95% CI: 0.61, 0.99). Women with lower education than their partners were significantly more likely to experience IPV than women with the same or more education as their partner. Indicators of economic status of women were not associated with IPV outcomes in the expected directions. Findings support policies and interventions seeking to raise the status of women as a mechanism to reduce IPV. Future research can explore economic empowerment and IPV, as well as the interaction between household and neighborhood-level factors. [ABSTRACT FROM AUTHOR]