Metamorphic Rocks Overview
24 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What are the three major classes of metamorphic rocks?

Contact metamorphism, pressure metamorphism, and regional metamorphism.

How does the texture of metamorphic rocks relate to their mineral composition?

The texture is determined by the types of minerals present, particularly lamellar minerals in foliated rocks.

What is the primary mineral composition of basalt, and how does it form?

Basalt is comprised mainly of magnesium and iron-rich minerals and forms from the rapid cooling of mafic lava.

Describe the QAPF classification in relation to granite.

<p>The QAPF classification categorizes granitic rocks based on the relative percentages of quartz, alkali feldspar, and plagioclase.</p> Signup and view all the answers

What is the significance of foliation in metamorphic rocks?

<p>Foliation indicates the alignment of mineral grains under pressure, affecting the rock's strength and appearance.</p> Signup and view all the answers

What are the uses of basalt in construction?

<p>Basalt is used as building blocks, cobblestones, and for making statues.</p> Signup and view all the answers

Explain the formation process of granite.

<p>Granite forms from the slow cooling and solidification of silica-rich magma underground.</p> Signup and view all the answers

Why is granite considered a suitable material for pavements?

<p>Granite is highly resilient, porous, and low-maintenance, making it ideal for pavements.</p> Signup and view all the answers

What are the primary minerals that compose limestone?

<p>Limestone is primarily composed of calcite and aragonite.</p> Signup and view all the answers

How does sandstone resist weathering compared to other rock types?

<p>Sandstone is resistant to weathering due to its composition of quartz or feldspar.</p> Signup and view all the answers

What is orthoquartzite and what is its significance?

<p>Orthoquartzite is a pure quartz sandstone containing 90-95% quartz and is proposed for Global Heritage Stone Resource nomination.</p> Signup and view all the answers

What process primarily leads to the formation of limestone?

<p>Limestone primarily forms when calcite and aragonite precipitate from dissolved calcium in water.</p> Signup and view all the answers

Why is limestone prone to damage from acid rain?

<p>Limestone is prone to damage from acid rain because it is primarily composed of calcite, which reacts with acid.</p> Signup and view all the answers

How does marble differ from limestone in terms of formation?

<p>Marble is a metamorphic rock formed from limestone that has recrystallized under heat and pressure.</p> Signup and view all the answers

What is the main use of marble in construction?

<p>Marble is commonly used in construction for sculpture and as a dimension stone.</p> Signup and view all the answers

What notable feature does Ashgabat, Turkmenistan have regarding marble?

<p>Ashgabat has the world's highest concentration of white marble buildings.</p> Signup and view all the answers

What are granitoids and their significance in the continental crust?

<p>Granitoids are igneous rocks, primarily granite, that dominate the continental crust, providing key structural components.</p> Signup and view all the answers

Describe the process of sedimentation in the formation of sedimentary rocks.

<p>Sedimentation involves the accumulation and cementation of fragments from earlier rocks, minerals, and organisms, as well as chemical precipitates in water.</p> Signup and view all the answers

What is the predominant type of sedimentary rock, and what percentage does it constitute?

<p>The predominant type of sedimentary rock is shale, constituting about 82% of sedimentary rock volume.</p> Signup and view all the answers

What are the primary classifications of sedimentary rocks based on grain size?

<p>Sedimentary rocks are classified into clay, silt, sand, gravel, cobbles, and boulders based on grain size.</p> Signup and view all the answers

What characterizes the layer formation of sedimentary rocks?

<p>Sedimentary rocks are typically deposited in horizontal or near-horizontal layers, known as strata.</p> Signup and view all the answers

Explain the metamorphism process and its effect on original rocks.

<p>Metamorphism involves changing the original rock's temperature and pressure conditions, resulting in a profound alteration of its properties and mineral composition.</p> Signup and view all the answers

What percentage of the Earth's crust is made up of sedimentary rocks?

<p>About 7.9% of the Earth's crust by volume is composed of sedimentary rocks.</p> Signup and view all the answers

What is the significance of fossils in sedimentary rocks?

<p>Fossils in sedimentary rocks provide crucial information about past life and environmental conditions.</p> Signup and view all the answers

Study Notes

Metamorphic Rocks

  • Comprise 27.4% of the Earth's crust by volume.
  • Divided into three classes: contact metamorphism, pressure metamorphism, regional metamorphism.
  • Texture is influenced by the types of minerals, with foliated rocks mainly containing lamellar minerals.
  • Common examples include schists, gneiss, slates, phyllites, mylonite, marble, soapstone, and serpentine.

Basalt

  • Aphanitic (fine-grained) extrusive igneous rock, formed from rapid cooling of low-viscosity mafic lava.
  • Significant volcanic rock type observed in approx. 20 volcanoes annually across the Solar System.
  • Used in construction, cobblestone production, and to create statues.
  • Can be heated and extruded to produce stone wool, an effective thermal insulator.

Granite

  • Coarse-grained (phaneritic) intrusive igneous rock composed primarily of quartz, alkali feldspar, and plagioclase.
  • Forms from silica and alkali metal oxide-rich magma that cools underground.
  • Classifications based on QAPF, indicating varying percentages of quartz and feldspar.
  • Often contains mica or amphibole; leucogranites contain minimal dark minerals.
  • Resilient and porous, making granite suitable for pavement material.

Sandstone

  • Composed mainly of quartz or feldspar; colors vary based on regional influences.
  • Known for weathering resistance, used historically in construction and decorative arts.
  • Orthoquartzite, a pure quartz sandstone with 90-95% quartz content, proposed for Global Heritage Stone Resource nomination in Argentina.

Limestone

  • Carbonate sedimentary rock primarily made of calcite and aragonite minerals.
  • Forms through the precipitation of calcium minerals from water, with significant biological processes over the last 540 million years.
  • Represents 20%-25% of sedimentary rock, predominantly limestone with some dolomite.
  • Acts as a raw material for lime production but is vulnerable to acid rain, necessitating preservation efforts.

Marble

  • Metamorphic rock made of calcite or dolomite, characterized by a crystalline texture without foliation.
  • Originates from metamorphosed limestone and is used in stonemasonry for sculpture and construction.
  • Notable example includes Tennessee marble; Ashgabat, Turkmenistan, has the highest concentration of white marble buildings.

Sedimentary Rocks

  • Formed at Earth's surface through accumulation and cementation of rock fragments, minerals, and organic materials.
  • Characterized by processes of sedimentation, compaction, and cementation (diagenesis).
  • Classified by grain size: clay, silt, sand, gravel; also includes cobbles and boulders.
  • Comprise about 7.9% of the crust; 82% constitutes shales, with 6% limestone and 12% sandstone and arkoses.
  • Commonly contain fossils and are deposited in horizontal layers, known as stratified rocks.

General Notes on Metamorphism

  • Metamorphic rocks arise from any rock type subjected to high temperatures and pressures leading to a change in form.
  • This process transforms physical properties and chemistry, often occurring during continental plate collisions.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Rocks PDF

Description

This quiz explores the characteristics and classifications of metamorphic rocks. Understand the differences between contact, pressure, and regional metamorphism, and learn about the textures and minerals that define these rocks, including examples like schists and gneiss.

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser