Plate Boundaries - VOCABULARY Flashcards

What this module covers (Educational context)

• Self-Learning Module (SLM) for Science Grade 10, Quarter 1, Module 2: Plate Boundaries.
• Designed for home-based learning with guided activities, pre-tests, post-tests, and answer keys.
• Emphasizes understanding plate tectonics and the three types of plate boundaries: divergent, convergent, and transform fault.
• Notes include practical enrichment activities, map-based assessments, and a hands-on plate boundary modeling task.
• Important administrative/context details (from the module):
  • The module follows a pre-test -> learn -> post-test structure.
  • Learners are encouraged to consult their facilitator/teacher if they need help.
  • Copyright and citation notes are included in the module (government work, with permissions from copyright holders for borrowed materials).
• Key figures referenced (without images): Figure 1 (Map of Plate Boundaries), Figure 2 (Divergent Boundary), Figure 3 (Convergent Boundary), Figure 4 (Transform Boundary), Figure 5–7 (Convergent boundary examples), Figure 8 (Map of Plate Boundaries). The descriptions below reflect the content of these figures.

Quick recap: Plate tectonics (core ideas)

• Plate tectonics theory explains that Earth’s lithosphere is broken into large and small plates that move slowly over time.
• Plates are part of the lithosphere, which includes the crust and the upper mantle; the mantle underneath (asthenosphere) allows movement via convection.
• Plate motion is driven by convection currents in the mantle and other forces within the Earth.
• Plate interactions at boundaries produce most geologic activity: earthquakes, volcanism, and mountain building.
• The movement and interactions of plates explain the distribution of earthquakes, volcanoes, and major mountain belts.
• Subduction, volcanic arcs, trenches, mid-ocean ridges, rift valleys, island arcs, and mountain belts are all products of plate boundary processes.
• Energy and material recycling occur at boundaries (e.g., older crust recycled at subduction zones).

Key terms and concepts (glossary)

• Plate: discrete piece of the lithosphere that moves relative to other plates.
• Lithosphere: rigid outer layer consisting of crust and upper mantle.
• Asthenosphere: the partially molten layer beneath the lithosphere that allows plate motion.
• Convection current: circular movement within the mantle that drives plate motion.
• Divergent boundary: plates move apart; results in new lithosphere formation.
• Convergent boundary: plates move toward each other; one plate may subduct beneath another.
• Transform boundary (transform fault): plates slide past one another horizontally.
• Subduction: process by which an oceanic plate sinks beneath a less-dense plate; sources magma leading to volcanism and trench formation.
• Mid-ocean ridge: underwater mountain range formed by divergent boundaries at sea floor spreading.
• Rift valley: continental analogue of seafloor spreading; a divergent boundary that creates a valley.
• Island arc: a chain of volcanic islands formed by oceanic-oceanic convergence.
• Continental volcanic arc: volcanic arc formed at oceanic-continental convergence.
• Trench: deep elongated depression at subduction zones.
• Collision and mountain building: when continental plates converge, they crumple and form mountain belts (e.g., Himalayas).

The three main plate boundary types (overview)

• Divergent boundaries
  • Plates move apart, creating tension and new lithosphere.
  • Occurs at mid-ocean ridges (seafloor spreading) and continental rift valleys.
  • Often associated with earthquakes and magma upwelling forming new oceanic crust.
  • Also called a constructive boundary.
• Convergent boundaries
  • Plates move toward each other and interact in three subtypes:
    1) Oceanic-Continental boundary
    2) Oceanic-Oceanic boundary
    3) Continental-Continental boundary
  • Key outcomes:
  • Oceanic plate subducts beneath the other plate due to higher density, forming subduction zones, trenches, and volcanic arcs.
  • Two oceanic plates: older, colder plate subducts; island volcanic arcs form parallel to trenches.
  • Two continental plates: no subduction; collision leads to crustal thickening and mountain ranges.
• Transform boundaries
  • Plates slide past one another (strike-slip motion).
  • Characterized by transform faults; e.g., San Andreas Fault.
  • Crust is neither created nor destroyed; instead, lateral displacement occurs with earthquakes.

Divergent boundaries (in detail)

• Movement: plates move away from each other; construct new lithosphere as magma rises to surface and solidifies.
• Geological features and examples:
  • Mid-ocean ridges: seafloor spreading at oceanic divergence (new oceanic crust created).
  • Rift valleys: continental divergence forming a rift valley; can be associated with a spreading center in a continent.
  • Earthquakes occur at divergence boundaries due to tensional stress.
• Significance:
  • Creates new oceanic crust and helps explain the age distribution of the seafloor.
  • Drives continental breakup and potential formation of new ocean basins.
• Examples mentioned: boundaries between South American plate and African plate; Pacific plate and Nazca plate; North American plate and Eurasian plate.

Convergent boundaries (in detail)

• Movement: plates move toward each other; outcomes depend on the plate types involved (oceanic vs continental, oceanic vs oceanic, continental vs continental).
• Subduction zones occur when an oceanic plate sinks below another plate (denser oceanic plate sinks more readily; continental plates resist subduction due to lower density).
• Three subtypes with characteristic features: 1) Oceanic-Continental boundary
  • Oceanic plate subducts beneath continental plate; forms a continental volcanic arc on the overriding plate and a trench at the boundary.
  • Magma formed by subducted oceanic slab melts in the mantle, generating magma that rises to form volcanoes.
    2) Oceanic-Oceanic boundary
  • One oceanic plate subducts beneath the other, forming a volcanic island arc parallel to the trench.
    3) Continental-Continental boundary
  • Both plates collide; crust crumples and thickens, forming mountain ranges (e.g., Himalayas); little to no subduction and no trench or volcanic arc.
• Earthquakes are common at convergent boundaries due to intense deformation and subduction processes.
• Notable examples:
  • Eurasian plate and Philippine plate, Nazca plate and South American plate, Pacific plate and Australian plate (oceanic-oceanic or oceanic-continental cases vary by boundary).
  • Himalayas formed from Indian plate colliding with Eurasian plate (continent-continent convergence).

Transform boundaries (in detail)

• Movement: plates slide past each other horizontally; motion is parallel to the boundary.
• Key features:
  • Transform faults accommodate shear motion between plate blocks.
  • Associated with linear faults and undersea canyons or fault valleys; earthquakes are common.
• Example: San Andreas Fault (California) as a classic transform boundary.
• Important note: Transform boundaries often connect segments of divergent boundaries (mid-ocean ridges) and/or converge toward subduction zones.

Real-world connections and plates mentioned

• The Philippine plate moves toward the Eurasian plate (at a convergent boundary context in the module’s discussion).
• Major plate interactions highlighted include:
  • African plate vs. Arabian plate at some convergent settings
  • Nazca plate vs. South American plate at a convergent boundary
  • Pacific plate vs. Nazca plate interactions
• The Himalayas as a prime example of continental-continental convergence.
• East African Rift as an example of a continental divergent boundary producing rift valley features.
• San Andreas Fault as a classic transform boundary example.

How the module is structured for learners (learning aids)

• What’s In: descriptions of plate boundaries and lithosphere concepts; two crust types (continental and oceanic); convection current role.
• What I Need to Know / What I Know Before: pretest questions to gauge prior knowledge; emphasis on writing best answers, using a separate answer sheet.
• What’s New: exploratory descriptions of boundary types and key terms; short Q&A to build understanding of divergence/convergence and subduction concepts.
• What I Have Learned / What I Can Do: guided activities including creating a plate boundary model, labeling, and color-coding; scoring rubrics for the model outputs.
• Enrichment Activities: additional tasks to reinforce concepts (e.g., completing tables, drawing directional arrows, matching terms to definitions).
• Assessments: multiple choice and short-answer items focused on identifying boundary types, movement directions, and associated features (mid-ocean ridge, trench, volcanic arc).
• Word Search and crossword activities: reinforce terminology related to plate boundaries and related features.

Key diagrams and their implications (descriptions sans images)

• Figure 1: Map of Plate Boundaries – shows large and small plates including the Philippine Plate; illustrates slow, constant plate movement.
• Figure 2: Divergent Boundary – plates move apart; formation of new lithosphere; mid-ocean ridges.
• Figure 3: Convergent Boundary – plates move toward each other; subduction zones, trenches, volcanic arcs or mountain belts depending on plate types.
• Figure 4: Transform Fault Boundary – plates slide past each other; strike-slip motion.
• Figures 5–7: Convergent boundary comparisons – Oceanic-Continental, Two Oceanic Plates, Two Continental Plates; illustrate subduction zones and associated features.
• Figure 8: Map of Plate Boundaries – learners identify divergent, convergent, and transform boundaries on a global plate map.

Formulas, numbers, and quantitative references

• Convection and plate movement are described qualitatively in the module, but learners are encouraged to frame movement in quantitative terms as needed.
• A basic formula that appears in study notes for these topics:
  • Rate of plate movement (seafloor spreading) can be conceptually described by the relation
    ext{Rate} = rac{ ext{distance moved}}{ ext{time}}
  • Plate motion is typically on the order of a few centimeters per year, often expressed as cm/yr in textbooks.
• No explicit numerical data are given in the transcript beyond general descriptions; the notes above provide the framework to quantify movement when learners encounter measurements in activities.

Practice questions and study tips (from the module)

• Pretest-style prompts (concept checks):
  • What plate boundary is formed by the sliding of two plates? (Answer: Transform boundary)
  • What boundary separates plates moving apart? (Answer: Divergent boundary)
  • What boundary occurs when plates move toward each other? (Answer: Convergent boundary)
  • Where is subduction typically observed? (Answer: At convergent boundaries involving oceanic lithosphere)
  • What boundary is associated with Mid-Ocean Ridges? (Answer: Divergent boundary)
• Example multiple-choice practice (concepts you should be able to answer):
  • Convection currents drive plate motion; the lithosphere moves slowly but constantly due to mantle convection.
  • Youngest ocean floor is typically found at divergent boundaries (mid-ocean ridges).
  • The boundary between the Nazca Plate and the South American Plate is a convergent boundary (oceanic-oceanic or oceanic-continental depending on segment).
  • The crust and upper mantle together form the lithosphere.
  • Plate movement results in earthquakes and other geologic features at boundaries.
• Enrichment and project ideas:
  • Build a plate boundary model showing convergent, divergent, and transform boundaries with labeled features (trench, volcanic arc, island arc, magma, etc.).
  • Use the map in Figure 8 to identify plate boundary types and adjacent plates.
  • Complete the “Find the Boundary on the Map” activity to connect boundary types with real-world plate interactions.

Connections to real-world understanding and applications

• The concept of plate tectonics helps explain natural hazards (earthquakes, volcanic eruptions) and Earth’s major topographic features (mountain belts, ocean basins).
• Understanding plate boundaries supports interpretation of seismic and volcanic activity worldwide and informs hazard preparedness.
• The module’s emphasis on the Philippine context reflects the practical relevance of plate interactions in the region (e.g., earthquakes and volcanic activity in Southeast Asia).

Summary takeaways

• Plate tectonics posits moving lithospheric plates driven by mantle convection; their interactions create divergent, convergent, and transform boundaries.
• Divergent boundaries create new lithosphere (mid-ocean ridges, rift valleys); convergent boundaries recycle crust (subduction) and produce trenches, volcanic arcs, and orogeny; transform boundaries produce shear motion and earthquakes without crust creation or destruction.
• Real-world examples and map-based activities reinforce the spatial distribution of plate boundaries and associated geologic phenomena.

Quick reference (memory prompts)

• Divergent boundary: apart, mid-ocean ridge, seafloor spreading, constructive.
• Convergent boundary: toward, subduction, trenches, volcanic arcs or mountain ranges, destructive in oceanic contexts.
• Transform boundary: slide past, strike-slip, San Andreas Fault.
• Key features to identify on a map: trench (subduction), volcanic arc, island arc, mid-ocean ridge, rift valley, mountain belt.
• Common examples cited: San Andreas Fault (transform); Himalayas (continental-continental convergence); East African Rift (continental divergence); Nazca-South America boundary (oceanic-oceanic or oceanic-continental depending on segment).

Final note

• Use this set of notes to prepare for the exam, focusing on the definitions, boundary types, their geologic consequences, and real-world plate interactions. If you’d like, I can convert these into a printable study sheet or generate a set of practice questions with answer keys.