Ch 4- Rock- Sect. 3- Sedimentary Rocks
Identify a factor that is NOT responsible for the formation of sedimentary rocks. A. glacier B. magma C. river D. wind
B. magma
How is biochemical sedimentary rock different from chemical sedimentary rock?
Biochemical forms from the action of organisms or their remains. Chemical forms directly from water.
What process is occurring in this photo? A. cementation B. condensation C. crystallization D. evaporation
C. crystallization
What rock contains the hard remains of marine organisms made from minerals in seawater? A. basalt B. granite C. limestone D. marble
C. limestone
How do chemical and biochemical sedimentary rocks form?
Chemical sedimentary rocks form when minerals crystallize out of solution in water, and biochemical sedimentary rocks form from the action of organisms in water.
Does the rock coal contain any minerals?
No the footnote below the chart explains that the carbon in coal is not a mineral. Coal is made of carbon that is not crystalline.
If clasts are broken fragments that make up a type of sedimentary rock, what would be a characteristic of a nonclastic sedimentary rock?
Nonclastic sedimentary rocks would be more uniform, or made of a material that does not consist of fragments of other materials.
Why can't sediment size alone be used to identify a sedimentary rock environment?
Sometimes the same rock environment can produce rocks with a variety of sediment sizes. The shapes of sediment offer clues about the rock environment.
What is the most common biochemical sedimentary rock?
limestone
Deduce how a rock formed from an explosive volcanic eruption could resemble a clastic sedimentary rock.
rocks that form from explosive volcanic eruptions may be composed of broken rock fragments and ash glued together from the intense heat of the eruption. Clastic sedimentary rocks are also composed of broken minerals and rock fragments compacted and cemented together.
biochemical rock
sedimentary rock that was formed by organisms or contains the remains of organisms. (ex. coal and limestone)
What might happen to the sand in the valley if more sand is deposited on top of it?
the layers of sand would be buried under more layers of newer sand. Over time, the weight of the new sediment would squeeze out fluids and decrease the space between grains through compaction. This may lead to cementation of the sand.
What can happen to a rock when water flows through cracks or holes in the rock?
the water can dissolve some of the rock's minerals and carry them away.
Analyze the statement: As rock erodes, rivers carry dissolved minerals to the ocean, increasing the saltiness of seawater.
water can dissolve rock material and carry it to the sea. These dissolved solids eventually increase the concentration of certain minerals in seawater, making it salty.
Through what processes do sedimentary rocks form through?
weathering, erosion, transportation, deposition, compaction, cementation, and crystallization
How do chemical rocks form?
when water becomes saturated with dissolved solids. As the water evaporates, the solids crystalized out of solution.
Imagine you have 2 rock samples and know one is chert and the other limestone. How could you tell which sample was which?
you could identify limestone by adding hyrdrocloric acid to both samples. The sample that reacts by fizzing is the limestone.
In which was are both igneous and sedimentary rocks classified?
How they form
Compare and contrast the textures of conglomerate and breccia.
-both clastic sedimentary rocks -the clasts in a conglomerate are well-rounded -in breccia they are angular
What are two ways that existing rock material can be transported to a new location?
1. As dissolved material in water 2. as fragments carried by water, glacial ice or wind
List the terms below in correct order to describe the formation of clastic sedimentary rocks: transportation, cementation, deposition, erosion
1. erosion 2. transportation 3. deposition 4. cementation
Describe 2 ways in which sedimentary rocks can form.
1. when sediment or other fragments are deposited, compacted and cemented together 2. when minerals crystalize out of water.
Which process is illustrated in the last part of the diagram? A. cementation B. compaction C. metamorphism D. transport
A. cementation
What is the general term for a rock fragment present in a sedimentary rock? A. clast B. glass C. mineral D. pore
A. clast
What is the term for broken pieces of rock? A. clasts B. crystals C. glass D. layers
A. clasts
What can be determined by studying the shape of clastic grains? A distance they have been transported B. how they were eroded C. mineral content of the parent rock D. the the parent rock was
A. the distance they have been transported
carbonate rock
Any rock, such as limestone and dolostone, made up mostly of carbonate minerals. Will fizz when they come in contact with hydrochloric acid.
Which process squeezes fluids from between individual grains? A. cementation B. compaction C. erosion D. transportation
B. compaction
Examine the rock. What property indicates that it's a biochemical rock? A. foliated layers B. fossilized shells C. large rounded clasts D. minerals of different colors
B. fossilized shells
Which characteristics are used to classify a sedimentary rock such as sandstone? A. glass content and texture B. grain size C. luster and hardness D. texture and mineral composition
B. grain size and sediment
Distiguish among clastic, chemical, and biochemical sedimentary rock.
Clastic- made up of broken pieces of minerals and rock fragments Chemical- made from minerals that crystalize out of water Biochemical- sedimentary rock that forms from the remains of organisms.
What is the difference between compaction and cementation?
Compaction occurs when sediment is squeezed together by the weight of other sediment above it, and cementation occurs when sediment is cemented together by dissolved minerals.
Which is a clastic rock? A. coal B. limestone C. rock gypsum D. sandstone
D. sandstone
Explain why limestone appears in 2 different places on the chart.
Limestone can form as either a chemical rock made of calcite or as a biochemical rock made of fossils that are, in turn, made of aragonite or calcite.
Why do you think that, unlike igneous rocks, chemical sedimentary rocks are usually made up of only one mineral?
Magma is made from a complex mixture of material, which can result in a wider variety of minerals in an igneous rock. Chemical sedimentary rocks form when minerals crystalize out of water, so they consist of only the type of dissolved solid that was in the water.
clastic
Sedimentary rocks that are made up of broken pieces of minerals and rock fragments "broken"
Which type of sedimentary rock would have a greater resistance to breaking down: one that formed by compaction only, or one that formed by both cementation and compaction? Explain.
The rock that formed by cementation and compaction would have great resistance b/c it would have the added strength of the cement holding its grains together.
Compaction
This process is the weight from the layers of sediment forces out fluids and decreases the space between grains
cementation
This process is when minerals dissolved in water to crystalize between sediment grains.
When does a chemical sedimentary rock form?
When minerals crystalize directly from water
Coal is an example of a type of sedimentary rock called a(n) ___________________.
biochemical rock
What are clasts?
broken pieces of minerals or rock fragments
During ____________, minerals such as calcite or quartz crystallize between grains of clastic rock.
cementation
A ___________________ sedimentary rock is made of mineral and rock fragments.
clastic
How are sedimentary rocks usually classified?
clastic rocks chemical rocks or biochemical rocks
Classify the following sedimentary rocks as clastic, chemical, or biochemical: conglomerate rock gypsum fossiliferous limestone rock salt
conglomerate- clastic rock gypsum- chemical fossiliferous limestone- biochemical rock salt- chemical
chemical rocks
form when minerals crystallize directly from water
