Earth's Interior Structure & EvidenceANSWER KEY
Name: Period: Date:
REF STUDY GUIDE: Big Ideas Use to answer form questions
1.Earth's Layers: Earth has four main layers — crust, mantle, outer core, and inner core — each with distinct density, composition, and temperature. The crust is thin (5–70 km) and rocky, the mantle is thick (2,900 km) and slowly flows like hot plastic, the outer core is liquid iron-nickel (generating Earth's magnetic field), and the inner core is solid iron-nickel kept solid by immense pressure despite temperatures reaching ~5,000°C.
2.Seismic Waves: Seismic waves from earthquakes act like an ultrasound for Earth's interior. P-waves (compression) travel through solids and liquids, but S-waves (shear) cannot pass through liquids. When S-waves disappear at certain depths, scientists know they have hit liquid — this is how we discovered the outer core is molten. Changes in wave speed also reveal density boundaries between layers.
3.Indirect Evidence: No one has ever traveled deeper than 12 km into Earth (the Kola Superdeep Borehole), yet Earth's radius is 6,371 km. Scientists use indirect evidence — seismic wave behavior, density calculations, magnetic field data, and the composition of meteorites (which formed from the same material as Earth) — to build models of what they cannot directly observe.
DRAW KEY TERMS Google each → Images tab → sketch what you see
Differentiation
Process of separation by density when Earth was molten
seismic waves
Energy waves generated by earthquakes that travel through Earth
compression
Force that squeezes or pushes material together
density
Mass per unit volume of a material (g/cm³)
OTHER VOCAB: pressure · composition · mantle · P-wave · S-wave · crust · outer core
WRITE FOCUS QUESTION Your initial thinking
The deepest hole ever drilled — the Kola Superdeep Borehole in Russia — reached only 12 km. Earth's radius is 6,371 km. That means we have physically explored less than 0.2% of the distance to the center. Yet scientists can describe each layer's temperature, density, and composition with remarkable confidence. How?
How do we know what's inside Earth if no one has ever been there?
I think...TODO: author answer text
WRITE AFTER HOOK FORM Reflect before continuing
I learned that... TODO: author answer text
Station 1 — Seismic Wave Investigation
I observed that... TODO: author answer text
This shows that... TODO: author answer text
The key concept is... TODO: author answer text
CHECK DAY 1 CHECK-IN Before you leave
Q1: Based on today's investigation of earth's interior structure & evidence, explain one key finding using evidence from your data. Connect your answer to this week's focus question: How do we know what's inside Earth if no one has ever been there?
TODO: author answer text
Confidence:
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Earth's Interior Structure & Evidence (Day 2)ANSWER KEY
Name: Period:
Station 2 — Earth's Layers Analysis
The data shows... TODO: author answer text
This connects to what we learned because... TODO: author answer text
I can conclude that...
Station 3 — Design an Earth Model
The main idea is...TODO: author answer text
This connects to what we learned because...TODO: author answer text
I can apply this by...TODO: author answer text
DRAW CONCEPT MODEL Show your understanding visually
Draw a model that shows the main concept. Include labels and arrows to explain relationships.
TODO: author answer text
Labels included
Relationships shown
Key terms used
CHECK TEST YOUR THINKING Rate each: FALSE ← 1–2–3–4–5 → TRUE
1. Earth is hollow or has large empty caves inside.
F12345T
2. Earth is the same material all the way through.
F12345T
3. Plates float on liquid magma like boats on water.
F12345T
4. Convection only happens in the atmosphere (weather).
F12345T
5. Continents move fast enough to notice.
F12345T
Pick any TWO statements — especially any you rated 2, 3, or 4. Justify your rating with evidence:
Statement #___ — I rated it ___ because:
Statement #___ — I rated it ___ because:
THINK SCIENTIST CIRCLE DEBRIEF Reflect after class discussion
AHA! Moment
The one I changed my thinking most about is... TODO: author answer text
Remaining Question
I still wonder... TODO: author answer text
WRITE FOCUS QUESTION REVISIT Final written response
How do we know what's inside Earth if no one has ever been there?
TODO: author answer text
TODO: author answer text
TODO: author answer text
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