Sedimentary Rock Experiment

The final product!

I forgot to take pictures of this one, but I can use photos from last year to show what we did.  The students learned that Sedimentary Rocks are created by four processes.  First there is erosion, where the sediment is carried to a new place.  Then deposition, when the water or wind deposits the sediment in its new location creating a sediment layer.  As more layers of sediment builds on older layers, they create enormous pressure on the lower older layers which is a process called compaction.  As water seeps into these layers, it mixes with minerals already blended in the sediment.  This mineral water cements the sediment together forming rock when the water evaporates in the final process called cementing.  Students created a layer of sand and cement and placed it in the bottom of their cups (Erosion and Deposition).  Then they created a pea stone and cement layer that they pressed down on the sand layer (Erosion, Depostion, and Compaction).  They then, added water to these layers and final layer of plaster to act as the top layer of sediment.  A little more water was added to the plaster to finish it off and they set it aside to dry (Cementing).