TY - JOUR
T1 - The role of seamounts in the transport of heat and fluids
T2 - Relations among seamount size, circulation patterns, and crustal heat flow
AU - Kawada, Yoshifumi
AU - Seama, Nobukazu
AU - Urabe, Tetsuro
N1 - Funding Information:
This study was supported by the scientific program “Trans-crustal Advection and In-situ reaction of Global sub-seafloor Aquifer (TAIGA), ” sponsored by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan. Comments by two anonymous reviewers helped to improve the manuscript. We acknowledge the use of the graphing software, Generic Mapping Tools ( Wessel and Smith, 1998 ).
PY - 2011/6/1
Y1 - 2011/6/1
N2 - To evaluate the role of seamounts in the transport of heat and fluids, we performed numerical simulations of hydrothermal circulation within and around seamounts that protrude through low-permeability sedimentary layers. A cylindrical flat-top seamount model enables us to take into account crustal heat flow, and the radius and height (i.e., the radius/height ratio) of the seamount. We found that the flow patterns depend primarily on the aspect ratio of the seamount, and secondarily on crustal heat flow. A large seamount, with a radius of several tens of kilometers, cools itself by convection cells that form within the seamount, and this behavior is independent of crustal heat flow. In contrast, a small seamount, with a radius of several hundreds of meters, works as a fluid passageway, either as a fluid exit by discharging hydrothermal fluids at low crustal heat flows, or as a fluid entrance by recharging seawater at high crustal heat flows. The role of a medium-sized seamount varies according to crustal heat flow: it is cooled by a convection cell at low heat flows and works as a fluid entrance at high heat flows. We also found that an increase in crustal heat flow has the same effect on the fluid flow pattern as does an increase in seamount permeability or sediment thickness.
AB - To evaluate the role of seamounts in the transport of heat and fluids, we performed numerical simulations of hydrothermal circulation within and around seamounts that protrude through low-permeability sedimentary layers. A cylindrical flat-top seamount model enables us to take into account crustal heat flow, and the radius and height (i.e., the radius/height ratio) of the seamount. We found that the flow patterns depend primarily on the aspect ratio of the seamount, and secondarily on crustal heat flow. A large seamount, with a radius of several tens of kilometers, cools itself by convection cells that form within the seamount, and this behavior is independent of crustal heat flow. In contrast, a small seamount, with a radius of several hundreds of meters, works as a fluid passageway, either as a fluid exit by discharging hydrothermal fluids at low crustal heat flows, or as a fluid entrance by recharging seawater at high crustal heat flows. The role of a medium-sized seamount varies according to crustal heat flow: it is cooled by a convection cell at low heat flows and works as a fluid entrance at high heat flows. We also found that an increase in crustal heat flow has the same effect on the fluid flow pattern as does an increase in seamount permeability or sediment thickness.
KW - Heat flow
KW - Hydrothermal system
KW - Numerical simulation
KW - Oceanic crust
KW - Seamount
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U2 - 10.1016/j.epsl.2011.03.029
DO - 10.1016/j.epsl.2011.03.029
M3 - Article
AN - SCOPUS:79955658663
VL - 306
SP - 55
EP - 65
JO - Earth and Planetary Sciences Letters
JF - Earth and Planetary Sciences Letters
SN - 0012-821X
IS - 1-2
ER -