ARTYKUŁY INFORMACYJNE Poszukiwany świadek naoczny impaktu – kwarc wstrząsowy
Abstract
Shocked quartz – impact eyewitness wanted.
A b s t r a c t. Most of the craters on the Earth, produced by an impact of meteorite or other space object, have been masked by exogenous processes. Therefore, indirect indicators of the impact such as shocked quartz have been recognized. The impact metamorphism is visibly recorded within quartz by distinctive microstructures. However, only the planar deformation features (PDF) are unquestionable evidences of impact. They should be investigated with particular accuracy because of similarity to endogenic planar microdeformations such as: growth features or metamorphic deformation lamellae. The K/Pg boundary interval from the Polish Outer Carpathians (Skole Unit, Husów. Thrust Sheet, Bąkowiec section) have been studied. This note presents difficulties in identifying shock features in quartz grains collected from turbiditic material.
A b s t r a c t. Most of the craters on the Earth, produced by an impact of meteorite or other space object, have been masked by exogenous processes. Therefore, indirect indicators of the impact such as shocked quartz have been recognized. The impact metamorphism is visibly recorded within quartz by distinctive microstructures. However, only the planar deformation features (PDF) are unquestionable evidences of impact. They should be investigated with particular accuracy because of similarity to endogenic planar microdeformations such as: growth features or metamorphic deformation lamellae. The K/Pg boundary interval from the Polish Outer Carpathians (Skole Unit, Husów. Thrust Sheet, Bąkowiec section) have been studied. This note presents difficulties in identifying shock features in quartz grains collected from turbiditic material.