Yellow Band Tells the stories of rocks
Four more days into the school year and we are moving full steam ahead, as a band and as geologists.The Yellow Band began the week by making a very hot trek up to Corona Heights along with their fellow geologists in the Green Band. Taking the long way down to the park gave us the chance to explore the vast amounts of chert that make up the hill. The questions began almost immediately. "Why is it rust colored?" "How was it made?" "How old is it?" "What are the stripes?" "How are the stripes different than the layers?" Success!!! They were interested in rocks. We took some quiet time to sit with our rocks, observe them, sketch them, and record our observations and questions.As they sketched, they sat in the shadow of something very special, one of the world's largest occurrences of slickenside (a polished and striated rock surface that results from friction along a fault or bedding plane.) "It looks like China!" "How far into the ground does it go?" "How did that happen?" We certainly had a lot of questions to go back to school and research.Wednesday was filled with researching our questions. We discovered that the chert we found is a sedimentary rock rich in silica, formed from the tiny silica shells of marine plankton called Radiolaria. Its rust color reflects that there was a great amount of oxygen oxidizing small amounts of iron in the sediment as it became rock. Gever's introduction to the arc during Thursday's morning circle with the story of his rock couldn't have come at a better time. That was the day that the Yellow Band learneded that they would have Pet Rocks. Each of us brought in a rock that held some sort of importance to us. We are going to have some fun with this mini project. We'll create manuals and write stories or comics, telling the story of our rock, both scientifically and fictionally (come on, don't all rocks love living in a striped sock?)We wrapped up our week with what will become a weekly occurrence, our Friday Tea and Talk. This is a time we can share our feelings from the week, ask for support and suggestions on dealing with challenges or conflicts, and simply become a stronger band.Next week we'll continue to explore the rock landscape of San Francisco, research our rocks, and grow even more as a band.