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I was approached by a colleague regarding the rock cycle. I since I have check the internet, google like a typical student and found conflicting diagrams and information. I know that all rocks can become sedimentary, igneous and sedimentary can become metamorphic. Here where the disagreement comes in that sedimentary does or does not become igneous. If a dike comes through sedimentary rock layers would then turn to metamorphic, marble, quartzite, slate etc. If the sedimentary rock melts into the magma - how do you know? Although my major is ES, I haven't taught this particular topic yet. thnx

It's been my experience that more "elementary" rock cycle diagrams do not reveal how sedimentary rocks could become igneous rocks. They are much more "cyclic" and show that igneous rocks become sediment, sediment becomes sedimentary rocks, heat and pressure is applied until "voila" a metamorphic rock is born. Just like everything else in real life, it's just not that simple. The rock cycle more closely resembles a web and yes, sedimentary rocks can become igneous rocks. Volcanic activity (such as intrusions/extrusions) are one way, as are subduction zones at plate boundaries. More "advanced" rock cycle diagrams, especially those used at the college level, almost always acknowledge this. Hope that helps! Kendra

Thanks, After discussing it and thinking it more it seems possible not as likely for sedimentary to become igneous. If a pocket of magma is bubbling up from the mantle around sedimentary rock and actually melts the rock. I thought about this later, I had the idea that igneous was magma/lava and only came from inside the earth. And after all the definition magma is molten(melted) rock. All matter I can imagine has a melting point.

Karen, I am attaching a rock cycle lesson with cards that I have found very useful in my classes. I hope this helps you....it has a lot of basic rock cycle facts. Good luck and feel free to contact me through Private Message if I can be of further help.

Attachments

Eath_Science_-_Rock_Cycle_Lesson_Plan.pdf (0.09 Mb)

Rock_Cycle_Cards.pdf (4.92 Mb)

My coworker and fellow faculty member A. Laskowsky informed me of a great lesson plan that he had done with his students as an assessment on whether or not his students understood the rock cycle. After we have given them the information regarding the different rock types and the basics behind how it got there, his lesson plan allows them to show us if they understand through the use of crayons and shavings. By having them shave the crayons and using heat and foil (for them to apply pressure to their crayon shaving mix) they are able to experiment with different types of procedures and steps to create different layers, which pertain to the different rocks and how they are created. I will also be running a lab dealing with many different types of food; including gummies, cookies, marshmallows, crackers, cool whip, etc. Through the different types of food, they are going to have to figure out how to make each type of rock. I know this can be messy and out of control, therefore I am requiring them to come up with a procedure list that they will follow and as a class we will come up with a list of ingredients that they are allowed to bring in (this way you can deny them from bringing in ridiculous ingredients like cool whip or peanut butter, which can be incredibly hard to keep off of your floor). I like the idea of this lab even though i have not run it yet because the students are allowed to use their imagination and apply it to the knowledge they have as well as being able to plan and problem solve with many different scenarios. I will post a follow up to this lab once I am finished. I will most likely run this some time next week so any feedback and encouraging words like *good luck* would be appreciated!

Hello all, I recently completed the Rock Cycle unit with my students, and I find that keeping it basic with a lot of hands on activities, allows the students to see the cycle piece by piece firsthand. Before beginning the unit, I let them know that there are many more processes that go into forming specific types of rocks. However, I do give them extra credit if they go that extra mile to give me the "backstory" to any particular rock that we discuss during the rock identification lecture. Arlene, I absolutely LOVE the crayon rock cycle simulation lab!!! As posted earlier in the forum, the students would use crayon shavings and go through each step of the rock cycle. To answer your question about the Metamorphic rock phase, the shavings are heated gently with a hot plate until the edges of their sedimentary "rock" are melted and with the semi-melted shavings, the lab instructs the student to press them together with a vise for about 10 seconds. If you don't have a vise on hand then pressing them between two books work as well. If you'd like, I can send you the lab and pre-lab that I use for the rock cycle.

Thank you all for clearing up some of the confusion. I came across some similar questions when my class and I learned the rock cycle. Surprisingly, students picked up on the general concept rather quickly and easily. What I found to be difficult was describing sedimentary rock. Coming from the East coast, sedimentary rock was the primary type of rock we could observe in our community. In Hawaii, however, that is not the case. I was thrilled to find that the majority of students already knew about igneous and metamorphic rock. I was even able to learn from some of them! That was exciting. There were some moments when students would even demonstrate a little arrogance in their own knowledge. I'm wondering if there are any hands on activities or simulations that could demonstrate the rock cycle. In my own experiences, I've used a rock tumbler to demonstrate erosion and a potential method of change between igneous and metamorphic to sedimentary rock. Has anyone had any experience with simulations such as using other materials to show changes between the types? Would clay be an apppropriate model? For example, moldable clay experience a change when heat (from a kiln) and pressure are applied?

I just read about the crayons and the different foods! Great ideas. Thank you!

Just to add some more "fun" things to do about the rock cycle...there is a free app called "The Rock Cycle". It is in a storybook form; however, there are side branches that go further into the causes, types, and other things that students need to know.Kids like to explore all of the branches that this app provides. Could be used for an "App Quest".