GEOL 120: Mod 5 Post Quiz
As sediment is transported farther from its source it generally ______________________. (choose all that apply) becomes better sorted becomes better rounded becomes more poorly sorted increases in grain size becomes more angular decreases in grain size
Becomes better sorted, becomes more angular, decreases in grain size
The sedimentary rock shown in the image below contains sand, pebbles and cobbles that are partially rounded and made up of rock fragments that contain quartz, potassium feldspar, and micas. Was the sediment that makes up this rock deposited relatively close to the source of sediment or far from the source?
Close to the source
The rock pictured below contains clay-sized clasts of clay minerals. Which of these is the most likely environment of deposition for this rock? river channel desert sand dune beach alluvial plain deep ocean
Deep ocean
The red color of some quartz sandstones, such as the one pictured below, indicates ________________________. deposition in an environment with very little oxygen exposure to oxygen during deposition and the formation of iron oxides the precipitation of calcite cement holding the sand grains together
Exposure to oxygen during deposition and the formation of iron oxides
Sandstones are commonly made up of quartz sand grains. Why is quartz the most common mineral found in sandstones? (Select all that apply.) Quartz is very soft and breaks down easily Quartz is chemically resistant to weathering Other minerals, such as feldspars, will break down to clays
Quartz is chemically resistant to weathering Other minerals, such as feldsparts, will break down to clays
The rock pictured below contains clay-sized clasts of clay minerals. What would this rock be called? breccia siltstone rock salt shale limestone
Shale