需要帮助理解“最小化地壳均衡模型偏应力”意味着,地球科学堆栈交换江南电子竞技平台江南体育网页版 最近30从www.hoelymoley.com 2023 - 07 - 27 - t10:53:59z //www.hoelymoley.com/feeds/question/8836 https://creativecommons.org/licenses/by-sa/4.0/rdf //www.hoelymoley.com/q/8836 3 需要帮助理解“最小化地壳均衡模型偏应力”的意思 uhoh //www.hoelymoley.com/users/6031 2016 - 10 - 06 - t13:46:58z 2017 - 11 - 01 - t23:40:22z < p >尽管背景信息来自另一个身体除了地球,我想理解的术语是历史上地球物理性质。< / p >

Background:

I just read today's news "Saturn's moon Dione harbors a subsurface ocean" at Phys.org and this seems to bring the number of sub-surface oceans in the Solar System to about six (the number might vary depending on the level of certainty).

This news about Saturn's moon Dione comes from a model which uses gravitational data from recent flyby's of the Cassini spacecraft. The model is simultaneously applied to another one of Saturn's moons Enceladus.

Question:

My question is about the terms in the abstract of the recently published paper on the subject in Geophysical Research Letters and my question is limited to these terms which I believe come from Earth Science and apply to the understanding of the Earth's crust floating on it's magma "ocean" interaction with the hot and slightly viscous mantle below.

What is an isostatic model and what is deviatoric stress in the context of geophysics?

Enceladus' gravity and shape have been explained in terms of a thick isostatic ice shell floating on a global ocean, in contradiction of the thin shell implied by librations. Here we propose a new isostatic model minimizing crustal deviatoric stress, and demonstrate that gravity and shape data predict a 38 ± 4km-thick ocean beneath a 23 ± 4km-thick shell agreeing with – but independent from – libration data. Isostatic and tidal stresses are comparable in magnitude. South polar crust is only 7 ± 4km thick, facilitating the opening of water conduits and enhancing tidal dissipation through stress concentration. Enceladus' resonant companion, Dione, is in a similar state of minimum stress isostasy. Its gravity and shape can be explained in terms of a 99 ± 23km-thick isostatic shell overlying a 65 ± 30km-thick global ocean, thus providing the first clear evidence for a present-day ocean within Dione.

//www.hoelymoley.com/questions/8836/-/8839 # 8839 3 TechZen回答的需要帮助理解“最小化地壳均衡模型偏应力”的意思 TechZen //www.hoelymoley.com/users/652 2016 - 10 - 06 - t15:46:00z 2016 - 10 - 06 - t15:46:00z < p > < em >均衡< / em >组件之间的平衡意味着问候他们的地壳垂直运动由于密度的差异。< / p > < p > < em >偏应力< / em >有点侧向压力,粒子系统在更大的压力,对彼此。这就是使对象从摇摇欲坠的尘埃当施加垂直压力。< / p >

So, there model simulates the vertical stress on the crust more than it does the horizontal stresses. Enceladus is a puzzle because it's squished down at the poles much more than any other known moon or planet.

//www.hoelymoley.com/questions/8836/-/12592 # 12592 1 答案由你们- ti - 800为需要帮助的理解什么是“最小化地壳均衡模型偏应力”的意思 你们- ti - 800 //www.hoelymoley.com/users/5748 2017 - 11 - 01 - t23:40:22z 2017 - 11 - 01 - t23:40:22z < p > < / em > < em >均衡模型描述要么由于海拔差异变化密度(普拉特的地壳均衡模型)或质量(艾里的地壳均衡模型)。在行星的研究中,地形的变化可能是已知的,但是没有多少人对地壳的状态。通过地形变化,变化在质量(而:厚度)和/或密度可以推断地壳中使用一个均衡模型。< / p > < p > < a href = " https://i.stack.imgur.com/mJusu.png " rel = " nofollow noreferrer " > < img src = " https://i.stack.imgur.com/mJusu.png " alt = "普拉特# 39;s模型(左),艾里# 39;s模型(右)(来源:stanford.edu)”> < / > < / p > < p > < em >偏应力< / em >,正如你提到的,总压力-静水压力。在这种情况下提供的静水压力,在土卫二的地壳下面的海洋/壳(图像显示地球的情况下,地壳坐在软流层)。实施最低偏应力约束是一种迫使地壳接近均衡平衡(我们的想法是,高偏应力导致地壳内部变形,减少偏应力)。< / p >
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