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On 2 December, 2021 we recorded a sequence of drumbeat seismic events at Sangay volcano. This sequence lasted several hours and resulted in two explosive emissions whose eruptive columns reached 9 km above crater. Unexpectedly, these explosions did not produce any ash fallout in the inhabited areas around the volcano. This drumbeat sequence was produced after a series of morphological changes, including the opening of two new vents (W and N) and a landslide. These occurred during an enhanced period of ground deformation and degassing. Further analysis of satellite images allowed us to determine that this sequence was associated with the widening of the recently open vent north of the main crater, and the extrusion of a new lava flow. Timely communication of this event to the authorities and the population was ensured by the IG-EPN by following internal protocols. The corresponding short reports reached more than 300,000 people.

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El neoinstitucionalismo como paradigma científicoNeoinstitutionalism as a scientific paradigm ResumenLa emergencia del neoinstitucionalismo a inicios de la década del ochenta representa la innovación teórico-metodológica del viejo pensamiento institucionalista, pero sobre todo marca una ruptura respecto a los presupuestos de la revolución conductista que habían dominado la ciencia política en el período de posguerra. En ese sentido, la presente investigación se pregunta ¿De qué manera se configura el paradigma neoinstitucionalista? Para este propósito se plantea desarrollar el argumento según el cual el neoinstitucionalismo ha configurado no sólo un referente teóri-co-metodológico de investigación, sino además un cambio en la visión del campo disciplinar, lo que en última instancia ha permitido el desarrollo de una ciencia normal, sobre cuyo ejercicio se ha estructurado un paradigma compartido por una comunidad científica.Palabras claves: Neoinstitucionalismo, paradigma científico, ciencia normal. AbstractThe emergence of neoinstitutionalism at the beginning of the eighties represents the theoretical-methodological innovation of the old institutionalist, but above all it marks a rupture respect to the presuppositions of the behaviorist revolution that had been dominated political science in the postwar period. In this sense, the present research asks to what extent is there a neoinstitutionalist paradigm? For this purpose, it is proposed to develop the argument that neoinstitutionalism has configured not only a theoretical-methodological reference for research, but also a change in the vision of the disciplinary field, which has ultimately allowed the development of a normal science, whose exercise has structured a paradigm shared by a scientific community.

Determining the lithology, extent, origin, and age of hummocks can be challenging, especially if these are covered by successive deposits and lush vegetation. At Chalupas caldera, a late-Pleistocene silicic center that lies astride the Eastern Cordillera of northern Ecuador, we have tried to overcome these difficulties by combining geological observations and sampling, laboratory analysis (geochemistry, scanning electron microscope analysis and radiometric dating) and remote sensing techniques. Chalupas is the second largest caldera in the Northern Volcanic Zone of South America and its VEI 7 eruption, which occurred ∼0.21 Ma, has garnered the attention of the volcanological community. Our research highlights new observations of the post-caldera activity at Chalupas, beginning with the growth of Quilindaña stratovolcano (∼0.170 Ma), followed by the formation of Buenavista dome that is located 5 km eastward of Quilindaña’s summit. At the eastern foot of Buenavista dome we identify hummocky terrain covering an area of ∼20 km2. Collectively, the suite of techniques that we used helped to highlight geological features that shed light on the provenance of the hummocks and demonstrate that this topography may have originated from gravitational breccia flows from Buenavista lava dome. Numerical simulations were also performed to represent breccia flow transit and emplacement over the present caldera landscape and to view the potential hazard footprints of a future Buenavista dome collapse. For modeling we employed volumes of 20–120 Mm3 to visualize the consecutive traces of mass flow deposition and how the traces correspond to the hummocky landscape. Following the partial collapse of Buenavista lava dome, its rejuvenation is represented by tephra layers of several small eruptions that are dated at about 40 ky BP. These tephras represent some of the youngest eruptive activity recognized at Chalupas caldera. Our results contribute to the overall knowledge about Chalupas and demonstrate that eruptions at this important caldera are more recent than was previously reported.