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[Relative and Numerical Dating] Dating is complicated by the presence of unconformities. An unconformity is a gap left in the rock record due to erosion or lack of deposition. It is not a physical cavity but rather an uneven contact between beds of different ages. Label the three images below with one of the types of unconformities provided.

[Oceans] The following graph shows oceanic water temperature with reference to depth for equatorial, tropical, and polar (high latitude) waters. Select the line that represents the highest surface temperature.

[Earthquakes] Now, match the name of the seismic wave with the appropriate block diagram showing wave motion.

[Relative and Numerical Dating] Fossils can be dated using isotopic dating. Suppose the index fossil had a parent:daughter ratio of 4:12. Use the graph below to determine how many half-lives elapsed.

[Relative and Numerical Dating] To understand many of the geological processes that occur or have occurred throughout time, geologists need to be able to put rocks of different ages into order. The two main ways that geologists do this are through relative dating and numerical dating. We will be using these terms a lot throughout this exercise. Match these terms with their definitions.

[Ocean and Coastal Processes ] Beach erosion from storm surges and daily wave activity is a serious problem in many coastal communities. In an effort to stabilize coastlines, engineers design and install hardened structures such as the ones shown in the animation below. Select “Topics” and watch each animation. Living with the Coast Now, label the three images shown below.

[Earthquakes] When an earthquake occurs, energy is released in various types of seismic waves. Geologists separate these seismic waves into two categories: body waves and surface waves. The classification depends on whether the wave travels through the Earth’s interior (body) or only along the surface. Place each of the four main types of seismic waves into the appropriate category based on where it travels.  

[Earth’s Atmosphere]  The following video shows how aerosols moved across the globe over a three-month period in 2017. Honestly, it is spectacular to watch. Watch the video, maybe twice, and then answer the following question. Click here to open the video with closed captions in a new window.  

[Winds, Fronts, and Cyclones] Winds also influence weather patterns. They drive the formation of fronts and the genesis of storms. Which of the following forces control the direction and speed at which winds blow as the primary forces controlling wind?  

[Ocean and Coastal Processes ] The product of longshore drift along a sandy coast is the creation of a spit, a narrow bar of sand reaching out into a bay or channel. This is a picture of a recently formed sand spit. Which direction was longshore drift moving to create the spit?