Shale

Main Elements:

Si, Al, O, K, Fe

Chemical Composition:

Variable, primarily clay minerals (kaolinite, illite) and quartz, with organic matter

Density:

2.0-2.7 g/cm³

Compressive Strength:

10-100 MPa

Melting Point:

Variable

Formation:

Forms from compressed mud and clay in quiet water environments like lakes, lagoons, and deep ocean basins.

Composition:

Composed mainly of clay minerals, quartz, and organic matter. The most common sedimentary rock.

Types:

• Black Shale
• Red Shale
• Oil Shale
• Mudstone

Etymology:

Derived from the Old English word "scealu" meaning "shell" or "husk", referring to its tendency to split into thin layers.

Uses:

• Oil and gas source rock
• Brick making
• Cement production
• Pottery

Distribution:

Found worldwide, the most common sedimentary rock on Earth

Historical Use:

Used for thousands of years in pottery and brick making. Modern fracking extracts oil and gas from shale formations.

Symbolism:

Represents layers of time and Earth's history

Why is shale important?

Shale is the most common sedimentary rock and is a major source rock for oil and natural gas. It's also used in construction and pottery.

What is the difference between shale and slate?

Shale is a sedimentary rock that splits into layers. When shale is subjected to heat and pressure, it becomes slate, a metamorphic rock.