River
Lesson #12: River Rock Identification and the Rock Cycle
Time Frame: 45 minutes (or more)
Learning Standards:
Science
Earth and Space Science: Earth’s Materials
1) Recognize that water, rocks, soil, and living organisms are found on the
earth’s surface.
Science of Inquiry
1) Ask questions about objects, organisms, and events in the environment.
2) Tell about why and what would happen if?
3) Make predictions based on observed patterns.
4) Record observations and data with pictures, numbers, or written
statements.
5) Discuss observations with others.
Student will be able to:
1) Identify the type of rock collected from the river and write a story, with
drawings, explaining how the rock might have ended up along the river
bank.
Focus Activity: Give each student (or ask each student to retrieve) the rock that
they collected at the river. Ask the students to make a drawing of their rock and
write down at least 3 words that describe the rock.
Introduction: Introduce the idea that there are 3 major types of rocks –
sedimentary, metamorphic, and igneous. Tell the students that they will identify
their rock according to type and write a story about their rock.
Background Information: Sediments are pieces of weathered rock and organic
material (dead plants and animals) that settle out of the water. As rocks are
exposed to water and wind they are slowly broken down into sediments and this
process is called weathering. Wind and water move sediments and fast flowing
river water can carry heavy sediments along the bottom. Lighter sediments can
be suspended in moving water. The carrying away of sediments is called
erosion. Given a mixture of sediments and water, the sediments will settle into
layers, depending on weight. Over time, the weight of sediments on top of
sediments causes the bottom layers to form solid rock. Rocks made this way are
called sedimentary rocks. Metamorphic rocks form when existing rocks
experience heat and pressure, creating crystals. (Metamorphic rocks can come
from sedimentary rocks that experience heat and pressure.) Igneous rocks
form when magma (molten rock) from beneath the earth, comes to earth’s
surface and cools. This process of weathering, erosion, and rock reforming is
part of the rock cycle.
Activities:
Before Class please arrange with me to schedule a geology student to
assist with this geology lesson.
1) Write the three different types of rocks on the board: sedimentary,
igneous, and metamorphic. Discuss how these types of rocks are
different and how they are formed. Use examples of each type of rock to
share with the students.
2) Ask each group of students to make observations about the different kinds
of rocks and relate their observations to the formation of sedimentary,
metamorphic, and igneous rocks.
3) Ask the students to try to determine what type of rock they collected from
the river. Almost all of the rocks in the Hoosic River are metamorphic but
the geology student can assist with the identification.
4) Go over the process of how a metamorphic rock might end up in the
Hoosic River. For example, sedimentary rock (formed from sediments
under pressure) might experience heat and pressure to make a
metamorphic rock. When metamorphic rock is uplifted back to the surface
weathering could wear away pieces of this rock. These pieces might get
carried away by the river, ending up on the river bank.
5) Use the diagrams provided to briefly relate this process to the rock cycle
and discuss how the river is involved.
6) Ask students to make a short story or cartoon explaining how their rock
ended up on the bank of the Hoosic River. The story or cartoon should
include drawings and pictures and some writing. Assist individual
students as needed. (This process may take longer than one science
period depending on the level of detail.)
Closure: What happens during the rock cycle? How is the rock cycle like a
butterfly life cycle? Describe the rock cycle for a sedimentary rock. Describe the
rock cycle for a metamorphic rock. How is the river part of the rock cycle?
Assessment: Participation in class activities and discussions and creation of a
rock story with illustrations
Resources and Materials: Igneous, sedimentary, and metamorphic rocks (for
each group of students), paper, colored pencils and crayons, diagram of the rock
cycle, diagram of the sedimentary rock cycle