Daily Warm-Up Exercises Day 21 When we made sandstone, what was the purpose of sodium silicate? Sodium silicate formed a matrix, which is the stuff that cements the sand together. How can plants break rocks? Plant roots can grow into cracks. As they grow larger, they exert pressure that can cause the crack to widen and the rock to break. Sodium silicate is similar to a solution that happens in nature, but our solution was more concentrated so it would work faster. What does cemented mean? to get stuck together What is pressure? when something is squeezing or pushing on something else Daily Warm-Up Exercises Daily Warm-Up Exercises

Think about… Where would we find large collections of sand? How could sodium silicate get between the sand grains? beaches, sand dunes Water with a lot of dissolved sodium silicate could seep into the sand. 2 Daily Warm-Up Exercises 2

Sedimentary Sequence of Events Just after deposition, sand is loosely packed (lots of space) Sand is compacted over an extended period of time (very little space) Water carrying dissolved matrix seeps into the sand Sand is cemented together by matrix as water evaporates

Questions How can acid or water soak into sandstone? There are spaces between grains that can hold liquid. What type of rock is sandstone? sedimentary 4 Daily Warm-Up Exercises 4

Examine & Compare Use a hand lens to examine your model sandstone. Compare your model to Coconino Sandstone. Record similarities and differences. Think about: use a Venn diagram the origin of the sand the matrix that holds the sandstone together the size and compactness of the sand grains evidence for your conclusions