Journey to the Ocean Floor Oceanography is a science that draws upon the methods and knowledge of geology, chemistry, physics, and biology to study the ocean. The Pacific Ocean is the largest and the deepest ocean. Most submersible dives follow a similar pattern, emphasizing bottom transecting, collecting and photographing specimens. To understand our ocean floor exploration, you must first know something about the ocean floor. Follow along below as I summarize the parts of the ocean floor. First, to record our exploration and to submerge to the ocean’s floor, we will use Alvin, the world’s first deep-sea submersible.
Alvin is a three-person, self-propelling capsule-like submarine nearly eight meters long. Since the introduction of Alvin, other manned submersibles have been built and used successfully to explore the deep ocean floor. Now for the ocean floor, the continental margin is the ocean floor. It is located between the shoreline and the deep-ocean bottom. The deep ocean basin is a depression in the ocean floor that varies in depth and includes all of the deep parts of the ocean between the continents. The continental shelf regions also contain the highest amount of plants and animals that live on the ocean floor.
Next we have continental slope connects the continental shelf and the oceanic crust. It begins at the continental shelf break, or where the bottom sharply drops off into a steep slope. The continental slope together with the continental shelf is called the continental margin. Past the continental slope, we find the continental rise. As currents flow along the continental shelf and down the continental slope, they pick up and carry sediments and deposit them just below the continental slope. These sediments gather to form the large, gentle slope of the continental rise.
The deep ocean basin covers 30 % of Earth’s surface and has features, such as abyssal plains, deep-sea trenches and seamounts. The abyssal plain is the flat, deep ocean floor. It is almost featureless because a thick layer of sediment covers the hills and valleys of the ocean floor below it. Deep-sea trenches are the deepest parts of the ocean. We have reached the mid-ocean ridge which is two chains of mountains separated by a large depression that forms where two plates are drifting apart. Iceland, along the mid-Atlantic Ridge, is an example of this. Don’t forget bout the rift valley: In the rift valley new oceanic crust is being made. Lots of seismic activity is happening in this area. Here you will find the hydrothermal vents. Coming up are the seamounts. Most seamounts began life as volcanoes formed over hot spots in the ocean floor. After the crust moves off the hot spot, the volcanic activity stops. Some seamounts are so tall that their peaks pierce the ocean’s surface forming a volcanic island or, if there is more than one seamount, a volcanic island chain. Seamounts whose peaks have eroded and become a flat surface are called guyots.
Let’s explore the beautiful coral reefs. Don’t let them fool you, they are alive and dangerous. Coral reefs sometimes grow around seamounts that rise above the ocean waters. As the seamount sinks or its peak erodes, the seamount will disappear beneath the water leaving the coral ring. This is called an atoll. Now that the homework is over, we are ready to dive. Day One – When we began this project, I thought the ocean floor would be similar to a big sandy beach. Boy was I wrong! The ocean floor is actually irregular with mountains, plains, volcanoes, valleys, and ridges.
Using the manned submersible Alvin, we will venture to the bottom of the ocean. Initially, I was challenged with learning the ropes of life on a ship. There were many changes requiring my adjustment. Sleeping in small bunks, eating at odd times, and understanding military time are just three of the challenges. Conquering my fear of diving is probably the biggest challenge. Although life on the sea is exciting, after a while it becomes boring. Life on the ocean involves waking up at the same time, working at the same time, eating at the same time, and relaxing at the same time.
Today we are using a multi-beam bathymetry which will allow us to see the shape of the ocean floor. By taking these pictures scientists will have a very accurate water depth and terrain models. The detailed map and knowledge of the slope of the ocean floor acquired from the data will help us to predict the distribution of the ocean floor. To map the ocean floor, we will bounce a beam of sound waves off the ocean bottom through a technique called ‘echo sounding. ” Echo sounding involves using a transducer to transmit and receive sound waves.
By measuring the travel time of the sound wave from the transducer to the ocean floor and back, we can determine the water depth at that particular location. We haven’t reached the ocean floor yet. They are taking it easy because I am a rookie. Hope I don’t get seasick tomorrow… Well, more teasing for me if I am unable to keep up with the others as far as the documentation, work, and having a cast iron stomach to prevent seasickness. Day Two – It is a warm, clear morning. As ALVIN descends, I become acutely aware of the size of this vessel. ALVIN is very small.
I am not claustrophobic, but I am starting to feel the pressure. The one thing that saves me from panicking is what I can see from the portholes. Once we get below the ocean’s sun lit surface layers, the pitch-black ocean is illuminated by fluorescent organisms. What a beautiful sight. Never in my wildest dreams would I have imagined the ocean to be this beautiful. National Geographic and the films on the ocean simply cannot do justice to this beautiful place. I am going to stop writing just to enjoy the view. Day Three – We pick up where we left off on Day Two on our way to the ocean floor.
After descending through the water column for about an hour, we approach the ocean floor about 530 meters deep. The pilot switches on ALVIN’s spotlights and sets us on a course to the ocean’s floor. By manipulating ALVIN’s hydraulic, robotic arms, we are able to collect specimens from this area. Today we are going to use seismic techniques to take indirect pictures of the ocean floor. After taking the pictures, a geologist will need to examine them and record the findings. Another piece of equipment we will use is a coring drill. This drill will allow us to get fine-grained deposits on the ocean floor.
These samples will be used to study the mineral grains, microfossils, and water in the pore spaces to get a better picture of the past oceanic events. Again, the geologist will need to examine these samples. Today’s work is boring. Not that I don’t enjoy the view, but nothing can compare to what I saw yesterday. Well, back to work! Day Four – We have reached the end of our dive. Samples have been gathered, pictures have been taken and I have enjoyed the marvels of the ocean. The day will end with cataloging all of the specimens. With our worries and expectations behind us, our excitement will continue to build until we reach land.
What started out as a journey to explore the ocean’s floor turned into an exciting adventure as I overcame my claustrophobia to help with the dive! Besides accomplishing the goal of learning about the ocean floor, the most important lesson learned was about unpredictability. Ocean explorers are at the mercy of weather and technology. The ocean explorer must learn to adapt by letting problems roll off his back to continue with the research. This was an enjoyable project. I learned a lot about myself and what I am capable of handling under adverse circumstances.
Since I have already decided to work in the field of science, maybe a marine biologist would not be a bad choice. Then again, since I am no longer afraid of diving, I just might consider being an oceanographer. This is the end of this trip, so I will end my journal. Works Cited http://www. utdallas. edu/~pujana/oceans/guyot. html http://www. enotes. com/earth-science/abyssal-plains http:www. answers. com http://oceanexplorer. noaa. gov/explorations/02galapagos/logs/jun04/jun04. html http://www. cliffnotes. com/study_guide/topicArticleld_9605, articleld_9605. html
