Discoveries in oceanography have led to a greater understanding of the seas and oceans.
Oceanography is the study of the oceans and seas of the world, including their physical, chemical, ecological and geological properties. Although it is one of the newer scientific disciplines, people have been observing and studying ocean waves, tides and currents for thousands of years. From the time of the earliest human civilizations, people have sought to learn more about the large bodies of water around them. Since that time, mankind has looked to the oceans for solutions to address its basic needs, such as food, water, energy and transportation between its large bodies of land. Along the way, many discoveries have been made leading to a greater understanding of the world's largest bodies of water.
The Gulf Stream
During the mid-to-late 1700s, several studies were made of the ocean currents off the east coast of what is now the United States by then statesman Benjamin Franklin. While the actual existence of the Gulf Stream was already known, Franklin sought to understand it better to make use of it as a way of speeding up the delivery of mail between America and Europe. In the course of his studies, Franklin discovered that the many factors such as prevailing winds, the planet's rotation and the colder currents below and around the Gulf Stream were actually responsible for its direction and speed.
The Challenger Expedition
The Challenger Expedition between 1872 and 1876 was organized to study and gather data on ocean features such as seafloor geology, ocean currents, seawater chemistry and marine life. One of the expedition's greatest discoveries was of the Marianas Trench in the western pacific, which is over four miles deep. The deepest point in all the world's oceans lies in the same part of the pacific, within the Marianas Trench itself. It extends down to 37,800 feet and is now called the Challenger Deep.
Plate Tectonics
In 1915, the continental drift theory was proposed by a German scientist named Alfred Wegener. Due to findings at the time of similar animal and plant fossils in Africa and South America, as well as other continents, the suggestion was made that at one time all of these land masses were part of a single formation that had drifted apart over time. The shapes of these various continents did appear upon observation as though their coastlines could have fit together very neatly at one time. Later discoveries incorporating both the continental drift theory and another hypothesis on seafloor spreading led to the theory of plate tectonics. This theory suggests that the earth's crust is divided into large pieces that "float" upon another layer of rock called the asthenosphere. In this layer, rocks are under such heat and pressure that they behave much like a liquid upon which the plates themselves move. The theory of plate tectonics has since become the unifying theory that explains the movements and formations of the earth's surface.
Hydrothermal Vents
In 1977, hydrothermal vent communities were discovered, leading to the further discovery of hundreds of previously unknown species of marine life, including tube worms and giant clams. These vent sites, which are located at the ocean bottom where there is no light, were actually found to be plentiful with life. Further discoveries showed that the water's chemistry provided energy for such life forms in the same way that the sun provides energy for plants on the earth's surface.
Tags: Gulf Stream, bodies water, Challenger Expedition, continental drift, continental drift theory, drift theory, earth surface
