Name
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Understand basic concepts of coastal barrier island dynamics and the roles of the longshore current, tides, waves and storms.
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Become familiar with the common types of artificial structures used to modify shorelines and understand their effects on coastal environments.
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This prelab will prepare you to interpret, analyze, and predict coastal hazards associated with development on a barrier island.
 A PDF slide show titled “Coastal Photos” on OAKS. These photographs were taken at Folly Beach,

SC. (You will not use all of these for the pre-lab.)
Animations illustrating coastal processes on OAKS. You may need to download Adobe Flash Player to view the SWF files. It is available for free at http://get.adobe.com/flashplayer/ .

Several links to pertinent websites.
 Chapter 14: “Shoreline Landscapes” in your lab manual
Coastal processes are the actions by wind, water and human construction that shape our coastline. Folly
Beach is a very dynamic coastal environment, allowing visitors to witness some of these processes and the changes that they generate.
Go to http://oceanica.cofc.edu/ . On the left hand side, click the “Coastal Geology Online” button. Scroll down and click on “An Educators Guide to Folly Beach.” Go to ‘ Coastal Processes ’ .
Chapter 14 in your lab manual is another good resource for vocabulary, along with Dr. Pamela Gore’s website: http://facstaff.gpc.edu/~pgore/geology/geo101/coastal.htm
1. Click on BeachDriftV1.swf
, located on OAKS, and view the animation. It shows the longshore current flowing to the right, moving sediments down the beach in that direction. Note the angle at which the waves approach the coastline. What causes longshore drift?
2. Open SLIDE 1 IN THE COASTAL PHOTOS PDF FILE on OAKS and note the angle of waves and their approach. What direction is the longshore current in the image - TOP TO BOTTOM or
BOTTOM TO TOP ?
3. What is the primary direction of longshore drift in the southeast US? __________________________
4. Based on Questions # 2-3 above, where is north in the image on slide 1 - TOP or BOTTOM ?
5. Go to SLIDE 2 . Name two features found on transgressive (eroding) barrier islands that indicate the island is “rolling over” and explain them. ________________________________________________
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6. Go to SLIDES 3-4 - Morris Island Lighthouse. The lighthouse was not originally constructed in the water! So, how did it end up there?
________________________________________________________________________________
7. Go to SLIDES 5-7 - How does vegetation aid in the development of dunes and why are dunes so important to the coastal system?
________________________________________________________________________________
________________________________________________________________________________
On our field trip we will explore and interpret coastal features and processes which occur along much of the East Coast of the US and sandy shorelines worldwide. Our laboratory is Folly Beach, an island with a fascinating history, in terms of both human impacts and natural processes.
Our field trip will consist of eight stops or topics that are important to our understanding of barrier island geology, coastal processes, and how they relate to humans. Each team will be in charge of one stop on our itinerary and will present the pertinent information to the rest of the class. Your mission is to research, understand, and teach your classmates the importance of your topic. Each team will address the following
“big picture” questions for its particular stop:
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What is taking place here?
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Is this a natural or man-made process?
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What was it like in the past?
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What is the future of the area? How will it change over time?
For this pre-lab each student is individually responsible for answering the questions for their stop. You will then work with your teammates to prepare for your role as field trip guide. Your instructor will assign each team a stop on the tour. The stops or topics on the field trip include:
(stop at the top of the dune for a good “bird’s eye view”)
What is taking place here?
Is this a natural or man-made process?
What was it like in the past?
What is the future of the area? How will it change over time?

When were the jetties built?

What is the source of the rock used to build the jetties?

What is the purpose of the jetties?

How far do the jetties extend?

What was the impact of the jetties on Morris and Folly islands? What happened over the short term vs. the long term?
(same approximate location as Stop 1)
What is taking place here?
Is this a natural or man-made process?
What was it like in the past?
What is the future of the area? How will it change over time? st 70-90 years?

(same approximate location as Stop 1)
What is taking place here?
Is this a natural or man-made process?
What was it like in the past?
What is the future of the area? How will it change over time?

How does an ebb tidal delta form?
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Are ebb tidal deltas present between all barrier islands?
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What is the role of tides in the formation of an ebb tidal delta?

What is the role of waves in regards to an ebb tidal delta?
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What effect does an ebb tidal delta have on wave refraction and direction?
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What is the impact of an ebb tidal delta on the longshore current?
(Tarpon Pond and/or washover fans further along the inlet, if accessible)
What is taking place here?
Is this a natural or man-made process?
What was it like in the past?
What is the future of the area? How will it change over time?

What are washover fans? How do they form?

What is the role of hurricanes and s torms (nor’easters) in the formation of washover fans?
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Do washover fans indicate an erosional beach or one that is accreting sand?
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How do washover fans relate to island rollover?

Is the washover fan at Tarpon Pond visible in the 1994 aerial photo? What feature was in this location in 1994?
(oriented at ~right angles)
What is taking place here?
Is this a natural or man-made process?
What was it like in the past?
What is the future of the area? How will it change over time?

What is a groin? What is its purpose? How does it work?

How is a groin normally oriented relative to the shoreline?
 How are these groins different from the “typical” groin?

Looking at aerial photos (from Google Earth timeline series in lab) how has this section of beach changed over time?

How did the 1993 beach renourishment change the area around the groins?
(along the north end next to the bulkhead)
What is taking place here?
Is this a natural or man-made process?
What was it like in the past?
What is the future of the area? How will it change over time?

How are dunes formed?

What are crossbeds? How are they formed?

What does it mean if the dunes are truncated, (forming a vertical face) (eroded)?
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What is the role and importance of dune vegetation?

What are sea oats? What is special about their roots and growth pattern when it comes to stabilizing the dunes? Are sea oats protected in SC?

(showing areas of accretion and erosion)
What is taking place here?
Is this a natural or man-made process?
What was it like in the past?
What is the future of the area? How will it change over time?

What is the longshore current? What causes the longshore current?

Based on the accumulation of sand, what is the average direction of the longshore current?

Based on the waves today, which way is the longshore current flowing?

Is the groin functioning as you would predict?

What is the impact of a groin to the area to the north of the groin? To the south of the groin?
(with seawall)
What is taking place here?
Is this a natural or man-made process?
What was it like in the past?
What is the future of the area? How will it change over time?

What is a seawall? What is its purpose? What is its orientation to the shoreline?

What impacts can a seawall have on the beach in front of it?

What are problems associated with seawalls? Are any of these problems visible at the Schultz house?

Is it legal to build a seawall in South Carolina? On Folly?