5 points

Sedimentary

SEDIMENTARY ROCKS





CLASTICORGANICCHEMICAL

1 point each







CARBNON-CARBONATECARBNON-CARBCARBNON-CARB

1 point each

Name the Rocks. 3 points each.

S1.______S2.______

S3.______S4.______

S5.______S6.______

S7.______S8.______

S9.______S10.______

S11.______S12.______

QUESTIONS:3 points each. Use complete sentences for #1-4. No pronouns allowed.

1.

2.

3.

4

5.ABCD

6.ABCD

7.ABCD

8.ABCD

9.ABCD

10.ABCD

Lab #15Sedimentary

INTRODUCTION: Please read this as it contains information that will help you complete this lab successfully.

Sedimentary rocks are formed by the lithification (turning to stone) of sediments. Most of New York State has sedimentary rock as bedrock. Vast oceans once covered New York State, producing the sedimentary rocks. Most of the rocks that can be seen along New York roadsides are layered sedimentary rocks.

Clastic sedimentary rocks are formed by the deposition, compression, and cementation of broken rock (sediments). These rocks are classified by the size and shape of the sediments contained in them. Clay particles form shale, silt forms siltstone, sand forms sandstone, large rounded pebbles form conglomerate and large angular particles form breccia.

Some rocks are formed from living organisms or their shells. These are called organic sedimentary rocks. The remains or impressions of plants and animals found in rocks are called fossils. "Hard" parts of animals, such as bone and shells, are usually the only parts that become fossilized. Sedimentary rocks are the only rocks that have fossils in them. Any organic material would be destroyed in lava or magma and therefor no fossils are found in igneous rocks. Likewise, the pressure required to create metamorphic rocks would destroy fossils.

Chemical sedimentary rocks can be formed by evaporation (evaporites) or the precipitation from sea water (precipitates). Limestone, dolostone, halite and rock gypsum are all evaporites.

PROCEDURE:

PART ONE:

For each sedimentary rock, classify whether the rock is clastic, chemical or organic. Place the code letter and number under the appropriate category on the report sheet. Clastic sedimentary rocks show layering, feel very gritty, or have visible sediments. Organic sedimentary rocks have fossils or shell fragments in them. Chemical sedimentary rocks generally do not exhibit any of the characteristics of clastic or organic. They tend to be of one color and fairly solid in appearance.

When each rock has been classified, place one drop of dilute hydrochloric acid (HCl) on each rock. If the acid bubbles, the rock contains calcium carbonate (mineral calcite). The acid reacts with calcium carbonate to form carbon dioxide, a gas, which causes the bubbling. These rocks are called carbonates. If no bubbling occurs the rock is a non-carbonate. Write the code letter and number in each category under carbonat e and non-carbonate. This will begin to look like a family tree.

PART TWO:

Using the Earth Science Reference Tables, try to determine the name of the sedimentary rocks. The chart is divided into clastic and non-clastic (chemical and organic). Further descriptions on the chart can be used to pinpoint the rocks' names.

QUESTIONS: Use complete sentences for questions #1-4. No pronouns allowed.

1.How could a clastic sedimentary rock appear to be chemical?

2.Would sedimentary rocks form at high elevations or low elevations? EXPLAIN.

3.Why wouldn't fossils be found in igneous or metamorphic rocks?

4.Why aren't there many fossils of skin or muscle tissue of animals?

5.What would a rock formed by the compaction and cementation of angular sediments 1 cm. in size be called?

A)sandstone

B)breccia

C)conglomerate

D)limestone

6.Which rock is most likely to fizz in acid?

A.rock salt

B)gypsum

C)limestone

D)shale

7.Which rock is most likely formed by the precipitation from sea water?

A)sandstone

B)gypsum

C)conglomerate

D)bituminous coal

8.Which rock is composed of the smallest size sediments?

A)shale

B)siltstone

C)sandstone

D)conglomerate

9.Which property best describes a rock which has formed from sediments?

A)crystalline structure

B)distorted structure

C)banding of minerals

D)particles arranged in layers

10.Which property is used to classify the land-derived sedimentary rocks listed in the Earth Science Reference Tables?

A)particle size

B)fossil content

C)mineral composition

D)color