Interphases-of-the-layers-of-the-earth.pdf

Short Quiz: ½ crosswise 1. What element is the most abundant in the Earth’s crust? 2. What elements make up the inner core? 3. What keeps its solid phase of the materials in the inner core? 4. Identify the mechanical layers of the earth? 5. Name the chemical layers of the earth? 1. Enumerate t...

Short Quiz: ½ crosswise 1. What element is the most abundant in the Earth’s crust? 2. What elements make up the inner core? 3. What keeps its solid phase of the materials in the inner core? 4. Identify the mechanical layers of the earth? 5. Name the chemical layers of the earth? 1. Enumerate the lines between the layers of the earth. 2. How they know that the layer of the earth is solid, liquid and gas  Conrad Discontinuity: the discontinuity 1 between the upper and lower crust 2 Repiti Discountinuity 4 3 Lehmann discontinuity: the boundary between the outer core and inner core 5 They gained information about the Earth’s internal structure by studying how seismic waves travel through the earth. They measure the time it takes for both types of waves to reach seismic waves detecting stations from the epicenter of an earthquake. Primary waves refracted at core boundary  Secondary waves is absorbed only Interfaces mark the boundaries between the layers of the Earth Mohorovicic discontinuity- also known as Moho, is the interface between the crust and the mantle. Gutenberg discontinuity- marks the boundary between the mantle and the outer core. Lehman discontinuity- located between the liquid outer core and the solid inner core. In 1009, Yugoslavian seismologist Andrija Mohorovicic found out that the velocity of seismic waves changes and increases at a distance of about 50 kms below the Earth surface. This led to the idea that there is a difference in density between the Earth’s outermost layer and the layer that lies below it. The boundary between these two layers is called Mohorovicic in honor of him. P-waves are detected on the other side of the earth opposite the focus. A shadow zone exist. The existenc eof the shadow zone, according to German seismologist Beno Gutenburg could only explain if the earth contained a core composed of material different from that of the mantle causing the bending of the P- waves. To honor him, mantle –core boundary is called Gutenburg discontinuity In 1936, Inge Lehmann, a Danish seismologist discovered a new region of seismic reflection within the core. Based on the figure, we can say that the outer part of the core is liquid based on the production of an S-waves shadow zone, and the inner part must Lehmann be solid. Lehmann discontinuity boundary between the inner core and outer core. In honor to Inge Lehmann.  Conrad discontinuity The Conrad discontinuity (named after the seismologist Victor Conrad) is considered to be the border between the upper Repetti discontinuity continental crust and the lower one Conrad discontinuity Repetti discontinuity  Conrad discontinuity The discontinuity between the upper mantle and the lower mantle is known as Repetti Discontinuity. Repetti discontinuity