There are two main types of tectonic plates: Oceanic and Continental. Continental crust is mostly formed of granite and is commonly referred to as sial due to a large amount of silica and aluminium present. Continental crust is less dense than the basaltic oceanic crust, sima, which is comprised of silica and magnesium. Because it is denser, oceanic crust plunges beneath the continental crust. The division between the two layers is known as the Conrad Discontinuity.
Answer:
Tides have a cyclic time of 12hr and twice daily.
Explanation:
- Based on the question of high and low tide, Boston experiencing a neap tide or spring tide on 26 May that is at the time of 1.15AM is of 10.8 in height and at 1.41PM its 10.3 in height, which means that there is a rise in sea levels at the morning and evening hours once due to moon and other due to Coriolis force on body of water.
- The low tide at 7.28 AM has a height of -0.4 and -0.5 at 7.54. thus Boston experiences a decrease in heights of the tide. Thus there exist some variations within the tidal ranges varying magnitudes and velocities.
I imagine, it's A, they get a sense of the history of the area they are investigating.
