Download Wilson Cycle Stages e-i

Wilson Cycle Stages e-i
VA-SOL.SC.ES.8 STANDARD: The student will investigate and understand geologic
processes including plate tectonics. Key concepts include
VA-SOL.SC.ES.8.C > tectonic processes (subduction, rifting and sea floor spreading,
and continental collision).
Overarching concepts: Systems and cycles
Key concepts:
Subduction
Strike-slip
Convergent margin
Volcanism
Volcanic island arc
Continent collisions: Cordilleran and other
Instructional Objectives
Describe a typical Wilson Cycle and identify the stages
Describe each stage of the Wilson Cycle and subdivide the processes and features found
in each stage
Engage
Short video of a volcano in a convergent plate boundary.
http://youtube.com/watch?v=YRiJdnDoMjw
Explore
Students should arrange themselves into groups of 3-4. Groups are given latitude and
longitude coordinates of the Aleutian Islands (see image above), Andes mountains, and
the Himalayas. Ideally each group would have a laptop or PC and would use Google
Earth or Whirlwind to “fly to” these coordinates. If computer resources are not available
they would use world maps, geologic maps and geologic cross sections to explore these
locations.
Cross Sectional image of Aleutian Islands:
http://www.geology.um.maine.edu/geodynamics/analogwebsite/UndergradProjects2005/
Perry/html/background.html
Using Google Earth or Whirlwind, and associated geologic maps and cross sections,
groups are to record their observations on what they are looking at and hypotheses
regarding the processes at work in these areas. The students will also be working to
answer the following investigative questions, either supplied by the teacher or asked
orally as the students work.
"What processes do you think forms mountains?"
"Where do islands like those found in Alaska come from? How are they formed?"
"Is there a relationship between the formation of mountains and island chains?"
"How do the Andes Mountains differ from the Himalayas?"
As the students work, the teacher will walk around and make sure the students notice
important factors that will clue them in to determining something about the geologic
setting.
Explain
Students explain their observations and hypotheses. They should have come up with the
processes of convergent plate boundaries and subduction. If not, teacher leads them to
this using the materials provided. Then the teacher discusses a PowerPoint presentation
on the final stages of the Wilson Cycle. Also, the end of this presentation emphasizes the
cyclic nature of supercontinents. They are formed, broken apart, and reformed throughout
earth's history. Students will be asked to determine which stage of the supercontinent
cycle they think the earth currently is in.
Final stages of Wilson Cycle:
e. Volcanic island arc- creation of a subduction zone
f. Island arc/continent collision
g. Cordilleran mountain building
h. Continent/continent collision mountain building
i. Peneplained mountain- stable continental craton
Extend
Students revisit the Andes Mountains, Aleutian Islands, and the Himalayas as well as
new locations such as the Caribbean, Japan, and the Mariana's Islands (see image below).
Leading students to these locations or allowing them to discover them themselves should
be decided by the diversity of the class. If students need the extra support, then they
should be guided to these locations. If not, they should use their knowledge gained about
the characteristics of convergent plate boundaries to find the other examples. They
classify each location in its respective stage of the final stages of the Wilson Cycle. Once
students have completed and discussed their thoughts, teacher goes over correct
classification and explanation of the processes occurring in each area. This would act as a
wrap up of how plates converge and the process of subduction.
Evaluate
Exit card asks students to draw simple cross sectional representations showing the
different types of convergent plate boundaries and subduction zones.
Plans for Diversity
Group work is beneficial to all students in that disabled students are given support by
their peers but are still able to contribute.
Also, the pairing of the visual images in Google Earth with the knowledge of the Wilson
Cycle is beneficial to students with reading difficulties or impairements.
Lastly, the amount of support given in the extend section is based upon the diversity of
the class.
Connections
This lesson centers the material being taught and tested in the SOL's, tectonic processes
and plate tectonics, in a higher level concept of cycles, namely the Wilson Cycle. The use
of explaining this knowledge from a conceptual standpoint allows students to think
logically about the order and relation of each stage, rather than just learning about
subduction, volcanism, and continental collisions as disconnected entities.
In addition, this lesson would be paired with the previous lesson, which goes over the
beginning stages in the Wilson Cycle.
Reflections
This lesson uses a pairing of classical geology (maps and cross sections) with the new
technology of the Internet and Google Earth or the like. I believe that this is important.
Many students view geology as a subject for old fogies, rock collectors or something that
exists only in museums. Students must see that geology is all around us and, although we
might not see it, geologic processes like the movement of continents are always
occurring. I will view these lessons as a success if my students show interest in learning
more and ask me questions, rather than me firing questions at them all the time. The
knowledge obtained in this lesson should lead them to questions regarding places like
Indonesia, Alaska, and Iceland as being very geologically active. If students relate the
knowledge obtained in this lesson to future lessons on earthquakes and volcanoes, they
are beginning to see the systemic nature of the earth, which is the ultimate goal.