[Winds, Fronts, and Cyclones] High- and low-pressure systems strongly affect when and where winds blow. Read each description and select whether it is describing a high- or low-pressure system.  

 [Minerals] A cation is a positively charged ion. An anion is a negatively charged ion. Below are six common mineral-forming cations and anions. Match / identify each ion into the correct grouping.

[Plate Tectonics] In the animation below, select the “Topics” menu, and then select “Hot Spots.” Watch the animation on hot spots Hot Spot Formations Based on the description of hot spots provided in the video, select the oldest volcano in the chain of islands pictured below.

[Volcanic Hazards] During gradual heating of a rock, which type of minerals melts first?

[Plate Tectonics] Let’s look at subduction zones in more detail. Label the different parts of the subduction zone using the terms below.

[From Big Bang to Blue Marble] If the pressure at 40 km depth is approximately 10,000 bars, which scenario best explains this increase?

[Minerals]  Another important test is determining how many planes of cleavage a particular mineral has. Look at the mineral below. A knife was used to break the mineral into smaller fragments. How many planes of cleavage does the mineral have?

[Minerals]  Field Work Question:  One of the first tests geologists run on unknown minerals is the “luster” test. Look at the mineral below. What kind of luster does it have?

[From Big Bang to Blue Marble] Why does the geothermal gradient vary at different depths inside the Earth?

 [Minerals] When minerals cool slowly, they tend to form larger, better-developed crystals. We use the terms “euhedral,” “subhedral,” and “anhedral” to describe different levels of crystal development. Below is a cartoon rendering of the edge of an amethyst geode. Drag the labels to the correct part of the image to show where each of the different types of crystals appear to have formed.