any collection of things that have some influence on one another can be thought of as a system. when we talk about a system, we are also talking about all the parts that should be included, how those parts interact with one another, and to how the system as a whole relates to other systems. we think of earth as both an open and a closed system: energy enters and leaves (open system) but matter does not (closed system). matter flows between reservoirs or sinks along pathways or fluxes.

there are three types of reservoirs in the lithospheric cycle: igneous, metamorphic and sedimentary rocks. various processes, such as burial and melting, volcanism, or erosion move this material from one reservoir to another. the major process that drives the rock cycle is plate tectonics, the movement of earth's crustal plates that is driven by convection currents of the magma within the earth itself.

students are investigating the types of rocks found in various locations throughout california, the state where they live and attend school. what hypothesis might the students formulate to guide their research on rock formation, given that they live in california?
a) if volcanoes are the source of land masses in california, that most of the rock in the state should be igneous.
b) if california is the site of several plate boundaries, we would expect to see mostly metamorphic rock at the boundary sites.
c) if there is movement at plate boundaries and sediment is the result of erosion, then we would expect to find mostly sedimentary rock at plate boundaries.
d) because there are mountainous regions in california and sedimentary rock is the result of erosion, we would expect to find mostly sedimentary roc