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Una estructura de impacto de anillos múltiples de 20 km de diámetro en el Mar del Norte
Simon A Stewart1, Philip J Allen
1BP plc, Burnside Road, Dyce, Aberdeen AB21 7PB, UK. stewartsa1@bp.com
Nature
|August 2, 2002
Resumen
Una estructura de impacto bien conservada de 20 km de ancho con diez anillos concéntricos fue descubierta en el Mar del Norte. Este hallazgo desafía las suposiciones anteriores sobre la formación de tales cráteres de impacto en planetas terrestres.
Área de la Ciencia:
- Geología Geología Geología.
- Ciencias planetarias Ciencias planetarias.
- El cráter de impacto es el cráter de impacto.
Sus antecedentes:
- Los cráteres de impacto terrestres a menudo están erosionados y mal conservados.
- Investigaciones anteriores sugirieron que las estructuras de impacto multi-anillo a pequeña escala eran poco probables en planetas terrestres.
Objetivo del estudio:
- Para describir una estructura de impacto de múltiples anillos recién descubierta en el Mar del Norte.
- Para analizar la formación y preservación de esta estructura de impacto.
Principales métodos:
- Análisis de datos tridimensionales de reflexión sísmica.
- Mapeo de estructuras de anillos concéntricos en la tiza del Cretácico y las pizarras del Jurásico.
Principales resultados:
- Descubrimiento de una estructura de impacto de 20 km de diámetro con al menos diez anillos concéntricos.
- La estructura está bien conservada debajo de los estratos terciarios, que datan de hace 60-65 millones de años.
- Anillos concéntricos identificados como estructuras de graben delimitadas por fallas, que acomodan la extensión posterior al impacto.
Conclusiones:
- La formación de estructuras de impacto de múltiples anillos a esta escala es posible, incluso en planetas terrestres.
- Las estructuras de anillo probablemente se formaron a través del desprendimiento en capas débiles de roca.
- Este descubrimiento proporciona nuevos conocimientos sobre los procesos de formación de cráteres de impacto.
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