Weathering and SS composition Warm-Up

Your Name

Essay Question

You have described a sandstone rich in feldspar grains. Discuss several ways in which you can account for the presence of the feldspar in the framework of this rock. Be sure to consider such factors as the composition of the source rock, climate in the source area, topography of the source area (especially relief), and overall tectonic setting of the source. Remember that weathering is an integral part of today's discussion.

Multiple Choice Questions

Hydroloysis reactions are especially important in the chemical weathering of unstable silicate minerals. How is the hydrogen ion produced, so that hydrolysis can proceed?

hydrogen ions are directly dissolved in rainwater from the atmosphere

hydrogen ions are produced when rainwater begins to react with bedrock

hydrogen ions are produced when clay in the soil begins to break down

hydrogen ions are produced when carbon dioxide reacts with water

A granitic source rock is exposed in a semi-arid setting, of low relief and tectonic stability. The depositional basin is several hundred kilometers from the source, and the environment of deposition is a beach and shoreface setting. The most likely composition of the resulting sandstone will be

quartz sandstone

lithic sandstone

feldspathic sandstone

none of the above