1. Title of notes: trenches
Pg. 24 & 25 RS

2. Goal for lesson: (Learning target) I’ll know I’ve got it when…
I can draw how a trench is formed.
Today I am…
Learning about how tectonic plates movement leads to geological features.
So that I’ll be able to…
understand how our geological features formed on Earth.
I’ll know I’ve got it when…
I can draw a diagram of a trench and label it correctly.

3. Trench
Trench: a long, narrow, deep depression in the ocean floor, typically one running parallel to a plate boundary and marking a subduction zone.
Can be up to meters (4.5 miles) deep
Form at a convergent boundary:
An oceanic – continental plate
An oceanic – oceanic plate

4. Trench CONDITIONS
water pressures more than 1,000 times greater than the surface
constant temperatures just above freezing
no light to sustain photosynthesis
Many of the organisms living in trenches have evolved surprising ways to survive in these unique environments

5. subduction
a geophysical process in which two or more of Earth's tectonic plates converge and the older, denser plate is pushed beneath the lighter plate and deep into the mantle, causing the seafloor and outermost crust (the lithosphere) to bend and form a steep, V- shaped depression
Subduction also generates an upwelling of molten crust that forms mountain ridges and volcanic islands parallel to the trench.
Examples of these volcanic "arcs" can be seen in the Japanese Archipelago, the Aleutian Islands, and many other locations around this area called the Pacific "Ring of Fire."

6. FIRST STOP IS JAPAN
Japan

7. MARIANA TRENCH Deepest part of the earth
10, 994 meters or 6.8 miles deep (known as the Challenger Deep)
Formed by ocean-to- ocean subduction
Oceanic – oceanic crust converge and the older crust subducts underneath newer crust. Convergent boundary
Located in the Pacific Ocean near Japan

8. The trench is deep enough that Mt. Everest could fit in its place

9. Snailfish
Ghostfish

10. Mariana Trench

11. Notebook Activity Pg. 24 LS Create a diagram of a trench and label.
Convergent boundary
Oceanic crust (plate) older crust
Oceanic crust (plate) newer crust
Subduction zone