Marine geophysics is a branch of science which deals with the studies about the application of the geophysical methods to the issues of the marine geology. In the marine geophysics, every principal branches of the geophysical knowledge is involved such as heat-flow information is collected from the midoceanic ridges and the ocean floors. In the marine geophysics seismic refraction and reflection methods are used in order find out the thickness of the oceanic crust and sediment thickness. Marine geophysics also comprises geomagnetics since it is applied to the samples of the oceanic rocks in the paleomagnetic investigations and lots more. Marine geophysics is closely related with the problems and concepts of continental drift, , plate tectonics and seafloor spreading.
The plate tectonic paradigm, first quantitatively described more than 25 years ago, provides an integrated physical and chemical framework for understanding the geological evolution of Earth. Marine geophysicists and geologists played a critical role in the development of this paradigm. By linking marine magnetic anomalies to geomagnetic reversals of Earth's magnetic field, marine geophysicists were able to confirm seafloor spreading and provide quantitative estimates of seafloor spreading rates. Through holes drilled by the Deep Sea Drilling Project, marine geologists were able to extend the geomagnetic reversal time scale back nearly 200 million years, providing a framework within which to reconstruct the past positions of the continents and the opening and closing of ocean basins.
Throughout most of the 1970s, the major emphasis in marine geophysics and geology was on large-scale kinematic descriptions of relative plate motions and their consequences for the geological evolution of ocean basins. However, by the 1980s, the focus of the field had shifted toward more process-oriented studies centered around understanding how oceanic crust and lithosphere arc created, how these processes are related to the underlying mantle, and the consequences of seafloor spreading on ancient ocean circulation and climate. Four themes currently dominate research in marine geology and geophysics: (1) the formation of oceanic crust and lithosphere along mid-ocean ridges, and the associated volcanic, hydrothermal, and biological processes; (2) off-ridge processes and their relation to mantle convection; (3) the structure and tectonics of active and passive continental margins; and (4) the record of past climate change and ocean circulation preserved in marine sediments.