Download Sedimentary Rocks

Sedimentary Rocks
by Colleen Buzby
Standards
VA-SOL.SC.ES.6
STANDARD: The student will investigate and understand the rock cycle as it relates
to the origin and transformation of rock types and how to identify common rock types
based on mineral composition and textures. Key concepts include
VA-SOL.SC.ES.6.A
> rocks;
VA-SOL.SC.ES.6.B
> rocks; and
VA-SOL.SC.ES.6.C
> rocks.
Lesson Plan Outline
Topic
Sedimentary Rocks: Identification and depositional environments
Instructional Objective(s)
SWBAT identify common sedimentary rocks.
SWBAT infer rock maturity based on sediment particles within rocks.
Engage
Crayon Activity, Part 2
We will take the 'igneous rocks' that we cooled during the igneous lab and flake it into 'sedimentary rocks'.
During this part we will also mention that these sediments could have come from metamorphic rocks as well.
Grain Size Introduction
Students will be confronted with tubs of five different sediments: clay, quartz sand, unsorted sand/clay mixture,
small rounded pebbles, and angular gravel. Students will touch each of these sediments to get a feel for grain
size distinctions. From this we can also discuss the pre-lithification of sedimentary rocks.
Explore
Pairs of students will be given a tray of sedimentary rocks and a flow chart to help them identify these rocks.
After having been exposed to mineral identification properties, they will already be familiar with some of the
common tests we preform on rocks and minerals. While they are trying to identify their rocks, I will walk
around to answer any individual questions. While I am doing this, I can also start to question students on how
they think some of these rocks formed and their relationships to other rocks. This will get their minds prepared
to make connections between the different rocks they see.
Explain
After students have had a chance to identify the rocks, we will come back together to discuss the rocks.
Questions to provoke students will include:
How are certain rocks related? Such as breccia and conglomerate?
What does grain size tell us about sediment maturity?
What does quartz content tell us about rock maturity?
Extend
After the discussion on maturity of sediments based on grain size and mineral content we will look at a
depositional environment diagram. Students will be told to figure out which rocks would be associated with
which depositional environments. They will be allowed into groups of four to decide how mature various rocks
are.
As they are working through this activity, we will break frequently to discuss differentiation of rocks over time.
We will consider how sediments self-sort into component parts. This will be related back to the differentiation
of magma, to create connections between the processes of sedimentary rocks and igneous rocks. This will help
students to realize the themes in earth science, such as differentiation and cycles.
Handouts: depomodels.PDF
Evaluate
During the identification time I will walk around and check to see that students are properly classifying their
rocks.
Plans for Diversity
I will choose groups that include students of different abilities so that students can learn from one another.
Connections
This lesson teaches students about the differences in sedimentary rocks. It teaches them how sediments change
over time in different environments.