Researchers at the CORK Canadian Observatory for Well Monitoring have found that cracked oceanic crust affects hot water circulation and plate hydration. The age of the crust is 3.6 million years.
The scientists measured the fluid pressure in the crust and matched the data with seismic records. They examined a variety of wells and tools on the North American seabed. To understand how compressible the crust is, the team compared the deformation of seismic surface waves to changes in reservoir fluid pressure caused by distant large earthquakes. This study was the first to use seismic frequency analysis in a marine environment.
The natural structure of the tough oceanic crust that forms a shell around the Earth contains cracks and faults. These cracks are hydrothermal pathways for the transfer of heat, water and chemical solutions between the ocean and the lithosphere, the earth’s solid shell. Researchers have discovered that there are many previously undiscovered cracks in the upper hundreds of meters of oceanic crust.
Scientists use seismic waves to uncover the nature of the oceanic crust, including lithology and structure. When seismic compression waves, or P-waves, propagate along the directions of the faults, the wave velocity remains almost unchanged.
The authors continue to monitor offshore wells elsewhere to better determine the fault patterns and hydrological properties of the earth’s crust.