Answer:
The astenosphere is located below the lithosphere
The mantle is composed of silicate material
Explanation:
The Earth has several different layers, and they can be presented in two different manners, depending on their chemical composition and their physical properties. According to the chemical composition the Earth has three layers, crust, mantle, and core, while in accordance to the physical properties it has five, lithosphere, astenosphere, mesosphere, outer core, and inner core.
The astenosphere is the second layer from the top, and it lies just below the lithosphere. It is also the upper part of the mantle. The mantle is a layer that is largely composed of silicate material, mostly silicate molten rock. It can easily be seen from the volcanic activities that this layer is composed of silicate material because the magma is rich in it, and the magma comes from this layer.
Answer:
D
Explanation:
you have to make groupes.
start with a² part and forget the rest from example.
-4a²-a²=? Now remember - and - is adding up. so -5a², which takes out options a and b, as there are 3a² instead of 5.
now let's take ab part and forge the rest.
-2ab+6ab=? that gives us 4ab. So option c, which says 8ab, is wrong. the last number isn't really important in this case because you've already seen the rest can't be.
Answer:1. Subduction 2. Deep-ocean trench 3. B
Explanation:
Did it on edge
Answer:
Layer B is older than intrusion A
Intrusion A is older than layers C, D, and E.
Layer B is older than layers C, D, and E.
Explanation:
The laws of biostratigraphy can be applied to this lithological section in order to ascertain the relative ages of the beds.
Some of these laws that are applicable to this problem are:
- Principle of superposition of strata : the oldest layer is always at the bottom of sequence while the youngest is on top in an undisturbed rock sequence.
- Law of cross-cutting: when faults and fractures cuts through a rock sequence, they are younger than the rock they cross through.
- Law of intrusions: Intrusions are younger than the rock layers they cut through
The geologic history of the beds here can be interpreted as thus:
- Lithology B was first deposited
- Then an intrusion A occurred and terminated at B
- Layers C, D and E were then deposited.
The oldest layer here is B followed by the intrusion A and successful deposition of C, D and E in that order.
