Sedimentary Rocks

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Transcript Sedimentary Rocks

ROCKS THAT FORM FROM AN ACCUMULATION OF SEDIMENTS DERIVED FROM PREEXISTING ROCKS AND/OR ORGANIC MATERIALS

Sediments that harden into rocks.

Here's a recipe for sedimentary rock: You take a layer of sand and put another hundred layers on top, Then let it sit for years and years, Let the pressure build You know, it may sound weird, But that's how you make sedimentary rock!

THREE KINDS OF SEDIMENTARY ROCKS

What does a rock want to be when it grows up?

A rock star!

FORM FROM SOLID FRAGMENTS (SEDIMENTS) OF OTHER ROCKS. EXAMPLES: SHALE, SANDSTONE, CONGLOMERATE SEDIMENTS COME FROM THE WEATHERING OF EXISTING ROCKS.

-> -> -> -> -> smallest

BOULDERS, PEBBLES, SAND, SILT, CLAY

FRAGMENTS ARE MOVED MOSTLY BY RUNNING WATER. WINDS, WAVES, AND GLACIERS ALSO MOVE PARTICLES.

THE FARTHER A PARTICLE TRAVELS THE ROUNDER IT BECOMES ROCK FRAGMENTS SEPARATE THROUGH HORIZONTAL AND VERTICAL SORTING

What do you do to a baby rock?

Rock it!

IS THE COMPACTION AND CEMENTATION OF ROCK FRAGMENTS THAT FORM SEDIMENTARY ROCKS.

In coarse sediments (gravel and sand) sediments do not stick together unless cemented. Dissolved minerals settle into spaces between grains and bind them together.

- THE LARGER THE SEDIMENTS IN THE ROCK THE MORE PERMEABLE (ABILITY TO LET WATER PASS THROUGH) THE ROCK.

CONGLOMERATE IS A MIXTURE OF LARGE ROUNDED PEBBLES CEMENTED TOGETHER BY SMALLER SEDIMENTS (BRECCIA HAS ANGULAR FRAGMENTS) SANDSTONES ARE MADE LARGELY OF QUARTZ GRAINS. (PERMEABLE) SHALE FORMS FROM THE COMPACTION OF TINY FLAKES OF CLAY. (IMPERMEABLE)

Where is a rocks favorite golf course?

Pebble Beach!

FORM FROM THE PRECIPITATION OF MINERALS OUT OF SOLUTION THE MAIN CAUSE FOR DISSOLVED MINERALS TO PRECIPITATE, OR DROP OUT OF THE WATER, IS EVAPORATION. (SHALLOW SEA ENVIRONMENT)

THIS RESULTS IN A CRYSTALLINE MASS OF INTERGROWN MINERAL CRYSTALS LIMESTONE - COMPOSED PRIMARILY OF CALCITE; FIZZES WITH HCL DOLOSTONE – FIZZES IN HCl WHEN POWEDERED ROCK SALT - SAME PROPERTIES OF HALITE ROCK GYPSUM SAME PROPERTIES OF GYPSUM

What’s a rocks favorite cereal?

Cocoa Pebbles!

Organic (Bioclastic) Sedimentary Rocks

Form from the remains of living things or rocks containing fossils Limestones - calcite and shells Coal (sooty)- burial of decayed plants; swamps Fossiliferous shale – Shale containing fossils

Sedimentary Features

Stratification – is the arrangement if different visible layers of rock.

When the type of sediments found in an area change, a new type of sedimentary rock forms Ex. Grand Canyon Fossils - are the remains, impressions, or any other evidence of plants and animals preserved in rock.

What’s a rocks favorite type of music?

Rock n’ Roll!

Ripple marks - are formed by the action of winds, streams, waves, and currents on sand, and form on the surface of bedding planes. Mud cracks - develop when deposits of wet clay dry up and contract. Geodes - are hollow spheres in which groundwater has deposited minerals (quartz or calcite crystals)