®®®® SIIA Público

Título del libro: Extreme Magnitude Earthquakes And Their Direct Economic Impacts: A Hybrid Approach
Título del capítulo: Chicxulub Asteroid Impact: An Extreme Event at the Cretaceous/Paleogene Boundary

Autores UNAM:
JAIME HUMBERTO URRUTIA FUCUGAUCHI; LIGIA LUCINA PEREZ CRUZ;
Autores externos:

Idioma:
Inglés
Año de publicación:
2015
Palabras clave:

Asteroids; Biodiversity; Earth (planet); Geomorphology; Asteroid impact; Biotic turnover; Cratering; Cretaceous/Paleogene boundary; Extreme events; Mass extinction; High energy forming


Resumen:

Crater-forming impacts represent a class of extreme events involving high-energy release and short time scales. Impacts constitute major geological processes shaping the surfaces and evolution of planetary bodies. The formation of large craters involves high pressures and temperatures resulting in intense deformation, fracturing, and melting. Impacts produce deep transient cavities, with excavation to deep levels in the crust, fragmentation, and removal of large volumes of rock. In this chapter, we analyze the Chicxulub impact and its effects on the Earth's climate, environment and life-support systems, in relation to the Cretaceous/Paleogene boundary. The boundary represents one of the major extinction events in the Phanerozoic, which affected about 75% of species. Effects of the impact have been intensely investigated, where the affectation in the evolution patterns was profound and long lasting. The disappearance of large numbers of species including complete groups severely affected the biodiversity and ecosystem composition in the marine and continental realms. There are several aspects involved in addressing the Chicxulub impact as an extreme event. First, we examine the impact event and cratering, time scales involved, and energy released. Next, we assess the impact's regional and global effects, which involve major perturbations in the ocean and atmosphere. From here, we discuss how and to what extent life-support systems are affected by large impacts, and what the fossil record tells about the extinction event and biotic turnover. In particular, how sudden or extended are the processes, extinction event and recovery temporal records. © 2016 by the American Geophysical Union. All rights reserved.


Entidades citadas de la UNAM: