The mohorovicic seismic discontinuity | 宇宙學 & 天文學 | 可汗學院
The Mohorovicic Seismic Discontinuity- boundary between crust and mantle (or Moho). 由 Sal Khan 創建.
看下節課: https://www.khanacademy.org/science/cosmology-and-astronomy/earth-history-topic/earth-title-topic/v/seasons-aren-t-dictated-by-closeness-to-sun?utm_source=YT&utm_medium=Desc&utm_campaign=cosmologystronomy
Missed the previous lesson? https://www.khanacademy.org/science/cosmology-and-astronomy/earth-history-topic/seismic-waves-tutorial/v/refraction-of-seismic-waves?utm_source=YT&utm_medium=Desc&utm_campaign=cosmologystronomy
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