Sea Floor Spreading Rates 110 85 Mya

The rate at which new oceanic lithosphere is added to each tectonic plate on either side of a mid ocean ridge is the spreading half rate and is equal to half of the spreading rate.

Sea floor spreading rates 110 85 mya.

High cretaceous ocean crust production rates have been causally linked to high global sea level and global co 2 due to increased outgassing. Make the necessary measurements to calculate the spreading rates on either side of the spreading center during the most recent 40 ma i e. This idea played a pivotal role in the development of the theory of plate tectonics which revolutionized geologic thought during the last quarter of the 20th century. Ranges of spreading throughout the world s oceans.

Slower spreading rates lead to a rough topography because the tectonic plate is allowed to cool before moving away from the ridge. Spreading rate is the rate at which an ocean basin widens due to seafloor spreading. The mid atlantic ridge for instance separates the north american plate from the eurasian plate and the south american plate from the african plate the east pacific rise is a mid ocean ridge that runs through the eastern pacific ocean and separates the pacific plate from the north american. While we can identify a seafloor spreading sequence with a general ene trend along the antarctic margin figs 4 and 5 from west to east we can observe an increase in spreading rate and tectono magmatic variations across the spreading segments from the potential field data e g.

R d t or r 9 5 10 7 cm 6 5 10 7 years 1 46 cm yr. However recent studies have questioned the empirical basis for high cretaceous global seafloor spreading rates high cretaceous sea level 230 320 m above present and the relationship between geochemical fluxes and spreading rates. A constant rate of ridge production has im portant implications for models of sea level and p co2 among other phenomena that have been linked to variations in global rates of seafloor spreading. For the two segments like those labeled a and b on the profile above and from 40 80 mya mya million years ago similar to the two segments labeled c and d on the profile above.

Spreading rates determine if the ridge is fast intermediate or slow. Use the above equation to calculate spreading rate. Seafloor spreading occurs along mid ocean ridges large mountain ranges rising from the ocean floor. The rates differ between the 3 spreading centers and along their respective boundaries.

Figs 3 and 5 seismic refraction velocity depth data e g. This data table provides spreading rates for divergent boundaries spreading centers in the pacific atlantic and indian oceans.