Title: Finite element analysis of a near impact event

Author: D. Seely, A.L. Bowman, N. Cho, M.F. Horstemeyer

Category: Stellar and Planetary Sciences

Conference Year: 2018

Abstract: Finite element simulations of near impacts of terrestrial bodies are presented to investigate possible deformation behavior induced by a massive body during the creation week and/or Genesis Flood. Using the laws of universal gravitation, a gravitationally loaded objected is subjected to the "pull" of a near passing fly-by object, and the resulting surface deformations are studied. An Internal State Variable (ISV) plasticity model for silicate rocks (Sherburn et al., 2011) is used to model the deformation behavior and to capture the history effects involved during the complex surface loading/unloading found in a near impact event. The model is used to simulate the earth and a "fly-by" object interaction and is able to accurately reproduce the internal pressure profiles of the earth and fly-by object. In this context, the fly-by object can be the original Moon, a meteor, or another type of large object that has moved through space to interact with the Earth. Due to the wide range of features that can drive surface deformations during a near impact event, a Design Of Experiments (DOE) methodology was used to independently investigate the influences of five parameters (stationary body size, core material, core/mantle thickness ratio, passing object mass, and passing object distance) concerning surface deformation. The results indicate that the core material and core/mantle ratio are the most dominant influence parameters on surface deformation. Examination of the ISV parameters of the mantle during deformation shows a complex relationship between the hardening and recovery terms of the model and the resulting plastic strain and surface deformation induced from the near pass event. Surface rise from the nearpassage of a Moon sized object could be as high as 800 m, in turn causing large tsunamis and possibly causing the Earth's crust to crack. For this first of its kind study, the conclusions provide understanding of the possible ranges of deformations observed from a near pass event and provides insights into possible catastrophic deformation mechanisms relevant to the young Earth paradigm.