Plate boundaries and stress types affecting Earth's crust.

It looks like you've uploaded a worksheet titled "Mountains, Earthquakes, and Volcanoes" that focuses on plate tectonics, specifically plate boundaries, stress, and strain in the Earth's crust. Below is a completed version of the worksheet with explanations for each section.

---

Worksheet: Mountains, Earthquakes, and Volcanoes

#### SABS: Students will investigate the scientific view of how the earth’s surface is formed.
> c. Describe processes that change rocks and the surface of the earth.

---

3 Kinds of Plate Boundaries

1. Divergent boundary – Plates move apart from each other.
2. Convergent boundary – Plates move toward each other.
3. Transform boundary – Plates slide past each other.

---

Stress

Due mostly to plate movements, the Earth’s crust is under a lot of stress.
There are 3 types:

- “A” occurs where plates pull apart, divergent boundaries, and is called tension.
*(Tension pulls rock apart, causing it to stretch and thin.)*

- “B” occurs where plates converge, convergent boundaries, and is called compression.
*(Compression squeezes rock together, often causing folding or thrusting.)*

- “C” occurs where plates move past each other, at transform fault boundaries, and is called shear stress.
*(Shear stress causes rocks to twist or slide sideways relative to each other.)*

> 🔍 Note: The diagrams show:
> - Tension (divergent): Rock is pulled apart → forms rift valleys.
> - Compression (convergent): Rock is squeezed → folds or faults form.
> - Shear stress (transform): Rock slides horizontally → fault lines like the San Andreas Fault.

---

Strain

Stress leads to strain on the crust which bends it. If it is warm, under the ground, it can bend. These features are called folds.

- Upturned folds are called anticlines.
*(An anticline is an upward-arching fold, resembling an "A" shape.)*

- Downward folds are called synclines.
*(A syncline is a downward-arching fold, resembling a "U" shape.)*

> 📌 Label the diagram:
> In the provided image of folded rock layers:
> - The upward-arching part is labeled as anticline.
> - The downward-arching part is labeled as syncline.

---

✔ Final Answer Summary:

- 3 Types of Plate Boundaries: Divergent, Convergent, Transform
- Types of Stress:
- A = Tension (divergent)
- B = Compression (convergent)
- C = Shear stress (transform)
- Folds due to strain:
- Upturned fold = Anticline
- Downward fold = Syncline

---

Let me know if you'd like this turned into a printable PDF or need help with related questions!