Exploring variation in hydrothermal alteration of the oceanic crust

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The Mid-Atlantic Ridge is the line of undersea mountains that represent where two pieces of the Earth's outer layer of rock are pulling away from each other due to heat circulating in the planet's interior. This spreading region experiences a lot of volcanic activity which creates new rock that forms the ocean floor in the Atlantic. As this region of the Earth spreads, seawater can interact with newly formed rocks by moving into open spaces or cracks in the rock. Understanding how seawater moves around in ocean floor rocks, and how it changes in different areas of the spreading regions, is important. The seawater chemically interacts with the rock and depending on temperature, the chemistry of the rock, and the type of fluid spaces in the rock, changes the types of minerals found there. These chemical changes to the rock control the way rocks respond to earthquakes in these areas, how magma makes its way to the surface through these rocks, and how spreading regions contribute to the carbon cycle of the planet through chemical reaction between rock and seawater. By drilling wells in an example of these spreading areas such as the Reykjanes Ridge, we can sample and examine the type of changes happening to the ocean floor rocks when they react with seawater. We can also lower special tools into these wells to record images and data that will let us understand how the spaces and cracks that allow seawater to move around in the rocks, change in different parts of the spreading ridges. This project will use these types of scientific data to investigate a number of questions we have about spreading ocean floors:1) Do the spaces and cracks in ocean floor rocks change in different parts of the spreading region?2) If changes exist, are they controlled by changing properties of the ocean floor rocks, for example, thickness, differences in the forces that cause spreading, or the nearby presence of large faults?3) What types of microscopic interactions occur that allow chemical reactions between seawater and ocean floor rocks and are they different in different parts of the spreading regions?4) If the types of microscopic interactions change in different areas of ocean floor spreading regions, what properties of the ocean floor rocks control this, such as their thickness and the types of spaces and cracks that let seawater into the rocks?