Sedimentary Rocks and the Rock Cycle

A collection of flashcards based on lecture notes regarding sedimentary rocks, the rock cycle, and related concepts.

What are the particle size classifications for detrital sedimentary rocks?

Boulder (>256 mm), Cobble (64-256 mm), Pebble (4-64 mm), Granule (2-4 mm), Sand (0.0625-2 mm), Silt (0.0039-0.0625 mm), Clay (<0.0039 mm)

What is the primary difference between conglomerate and breccia?

Conglomerate consists of rounded particles, while breccia consists of angular particles.

What does lithification of sand grains involve?

Compaction, which reduces pore space and drives water out, and cementation, which involves precipitation of minerals as cement.

What types of cement are involved in sedimentary rock formation?

Silica (quartz), Carbonate (calcite), Iron-oxide (hematite).

How does grain sorting affect porosity?

Well-sorted sediments typically have higher porosity due to uniform particle size and increased void space.

Define porosity in terms of sedimentary rocks.

Porosity is the percentage of void space within a rock.

What condition leads to the formation of quartz sandstone from granite?

Extreme chemical weathering of granite can lead to the source material for quartz sandstone.

Under what conditions does arkose form?

Arkose forms near its source with a short distance of transportation and typically in dry or arid conditions.

What is the significance of grain size in sedimentary rocks?

Larger particles require greater energy to erode and transport, while smaller particles can be moved at lower energy levels.

Which type of sedimentary rock is formed from deposited minerals through evaporation?

Chemical sedimentary rocks, specifically evaporites.

What is the most abundant chemical sedimentary rock?

Limestone, primarily made of calcite.

What are the key differences between detrital and chemical sedimentary rocks?

Detrital rocks consist of transported sediment as solid particles, while chemical rocks form from precipitation of minerals from solution.

Explain what coquina is.

Coquina is a type of limestone composed of broken shell fragments.

What is travertine and how does it form?

Travertine is a type of calcium carbonate rock that forms from deposits in hot springs and geysers.

Which environment typically deposits shale?

Shale is usually deposited in low-energy environments such as lakes and deep ocean settings.

What does the term "fissility" refer to in sedimentary rocks?

Fissility refers to the ability of shale to break along consistent layering or planes.

Why are wind and water considered effective in shaping sedimentary rocks?

Wind is effective in rounding sand-sized particles, while water can transport a range of particle sizes depending on energy.

How does distance of transport affect sediment characteristics?

Increased distance of transport typically leads to decrease in grain size and increase in roundness of sediment particles.