Short Paper
Short Paper:
Mantle Convection, The Forces Behind Plate Motion
PHSC 210-Spring B Term, Elements of Earth Science
February , 2014
Short Paper:
Mantle Convection, The Forces Behind Plate Motion
Introduction
The paper is about plate mantle convection, the forces behind plate motion. Lutgens & Tarbuck (2014) found “Convection is a type of heat transfer that involves the actual movement of a substance” (p. 177). Plate mantle convection is described by Merriam-Webster's Online Dictionary, as the slow creeping motion of Earth's solid silicate mantle convection currents: the concerted, collective movement of groups or aggregates of molecules within fluids and rheids, either through advection or through diffusion or as a combination of both; carrying heat from the interior of the Earth to the surface. The paper will briefly depict how mantle convection works, its methods of study, tools used, any new discoveries, and unanswered questions.
General Overview Most geologists accept convection currents as the most likely mechanism for plate motions. The cover of convective modes may appear as resulting from plate tectonics: large-scale flows driven by plates causing small scale convection in the upper mantle or held captive in a low viscosity zone underneath the lithosphere. The start of secondary flows could be responsible for the flattening of seafloor subsidence determined for lithospheres older than 70 Ma. (Dubuffet, et. al., 2000). The short version is that when something is heated up, there is a corresponding decrease in density, and the material rises. This is the reason hot air balloons work, and why the cold water is near the bottom of the lake and not on top (Nataf, 1991). This process also drives the major wind patterns. Rock is no different, and when heated it lowers in density and wants to go up (Anderson, 1998). The problem is that if it rises it's going to leave a void where it was. Just like in
Mantle Convection, The Forces Behind Plate Motion
PHSC 210-Spring B Term, Elements of Earth Science
February , 2014
Short Paper:
Mantle Convection, The Forces Behind Plate Motion
Introduction
The paper is about plate mantle convection, the forces behind plate motion. Lutgens & Tarbuck (2014) found “Convection is a type of heat transfer that involves the actual movement of a substance” (p. 177). Plate mantle convection is described by Merriam-Webster's Online Dictionary, as the slow creeping motion of Earth's solid silicate mantle convection currents: the concerted, collective movement of groups or aggregates of molecules within fluids and rheids, either through advection or through diffusion or as a combination of both; carrying heat from the interior of the Earth to the surface. The paper will briefly depict how mantle convection works, its methods of study, tools used, any new discoveries, and unanswered questions.
General Overview Most geologists accept convection currents as the most likely mechanism for plate motions. The cover of convective modes may appear as resulting from plate tectonics: large-scale flows driven by plates causing small scale convection in the upper mantle or held captive in a low viscosity zone underneath the lithosphere. The start of secondary flows could be responsible for the flattening of seafloor subsidence determined for lithospheres older than 70 Ma. (Dubuffet, et. al., 2000). The short version is that when something is heated up, there is a corresponding decrease in density, and the material rises. This is the reason hot air balloons work, and why the cold water is near the bottom of the lake and not on top (Nataf, 1991). This process also drives the major wind patterns. Rock is no different, and when heated it lowers in density and wants to go up (Anderson, 1998). The problem is that if it rises it's going to leave a void where it was. Just like in