American plate relative to the slow moving Caribbean
plate causing the opening of the Cayman Trough
(Figure 3j, k). Subduction of Atlantic Ocean crust is
observed along the Lesser Antilles Trench.
Ocean gateways
The present-day oceanic realm is divided into numerous
large ocean basins, the Pacific being the largest. Each of
these ocean basins is surrounded by continental areas
and connected to neighboring oceans via narrow, shallow,
and diffuse connections, called oceanic gateways. These
oceanic gateways are focal points for the large-scale
exchange of heat, water, salinity, and genes between the
oceans and play a major role in influencing global climate,
ocean circulation, and species diversity. The most wellknown examples of ocean gateways include the Tasman
Gateway, Drake Passage, Fram Strait, Panama Isthmus,
Greenland–Scotland ridge, Tethyan Seaway, and Indonesian Throughflow. Their shape, size, and depth change
over geological timescales and are largely controlled by
large-scale lateral and vertical motions of the many blocks
and basins that form during protracted periods of continental breakup and extension (or collision, uplift, and
shortening during oceanic gateway closure). Global ocean
basin reconstructions, such as those presented in Figure 3,
provide a broad basis for assessing the opening and closure of deep-water ocean gateways through time and thus
how plate tectonic movements influence global climate
and oceanography. The physiographic reconstructions
presented here highlight the timing of separation or amalgamation of continental blocks, assuming these areas to be
rigid features. However, we know that extensive deformation occurs over protracted periods at plate boundaries.
Therefore, the detailed evolution of many gateways such
as the Drake Passage, the Tasman–Antarctic Passage,
and the Panama gateway is dependent on understanding
the subsidence history of submerged fragments of continental crust or volcanic arc fragments (Lawver et al.,
2011). These are not included in the reconstructions
presented in Figure 3.
Ocean basin physiography and the age-area
distribution of ocean floor through time
Ocean basin reconstructions from 200 Ma to the present
imply that old mid-ocean ridge flanks in the proto-Pacific
and the Tethys oceans are gradually destroyed between
200 and 150 Myr ago, while new mid-ocean ridge systems
are initiated in a stepwise fashion between the late Jurassic
and early Cretaceous. This cycle leads to a substantial
younging of the ocean basins from the Jurassic to the Cretaceous period, followed by a gradually aging of the oceanic lithosphere from the Cretaceous seafloor spreading
pulse to the present day (Figure 4). The age-area distribution of ocean crust from 200 Ma to the present day implies
a mid/late Cretaceous sea-level high linked directly to the
transition from supercontinent stability to initial and
mature dispersal, first creating many new mid-ocean
ridges and flanks, which later experience stepwise subduction (Müller et al., 2008b). These cycles can also be linked
with long-term fluctuations in seawater chemistry, leading
to alternations between so-called aragonite and calcite
seas (Müller et al., 2013).
Summary and conclusions
Complete reconstructions of the physiogeography of the
ocean basins, starting with the breakup of Pangaea, have
only been achieved recently for the first time, reflecting
the difficulties involved in recreating now vanished ocean
basins and assimilating many types of geological and geophysical observations into complete models through time.
Although these ocean physiogeographic reconstructions
are limited as they only account for broad-scale processes,
they do provide an essential framework for creating
boundary conditions for understanding ocean circulation,
sediment accumulation, and ocean chemistry through
time, as well as paleoclimate and long-term sea-level fluctuations. Further studies on refining global plate motions
within a deforming plate framework as well as accounting
for vertical motions associated with areas of continental
breakup and collision will lead to more accurate reconstructions of ocean basins.
Bibliography
Afonso, J., Zlotnik, S., and Fernández, M., 2008. Effects of compositional and rheological stratifications on small-scale convection
under the oceans: Implications for the thickness of oceanic lithosphere and seafloor flattening. Geophysical Research Letters,
35, L20308.
Alvey, A., Gaina, C., Kusznir, N., and Torsvik, T., 2008. Integrated
crustal thickness mapping and plate reconstructions for the high
Arctic. Earth and Planetary Science Letters, 274(3–4),
310–321.
Atwater, T., 1970. Implications of plate tectonics for the Cenozoic
tectonic evolution of western North America. Geological Society
of America Bulletin, 81, 3513–3536.
Coffin, M. F., Duncan, R. A., Eldholm, O., Fitton, J. G., Frey, F. A.,
Larsen, H. C., Mahoney, J. J., Saunders, A. D., Schlich, R., and
Wallace, P. J., 2006. Large igneous provinces and scientific
ocean drilling: status quo and a look ahead. Oceanography,
19(4), 150–160.
Colpron, M., Nelson, J. A. L., and Murphy, D. C., 2007. Northern
Cordilleran terranes and their interactions through time. GSA
Today, 17(4), 4–10.
Cox, A., and Hart, B. R., 1986. Plate Tectonics: How It Works. Boston: Blackwell Science Inc. 400 pp.
Crosby, A. G., and McKenzie, D., 2009. An analysis of young ocean
depth, gravity and global residual topography. Geophysical
Journal International, 178(3), 1198–1219.
Gibbons, A. D., Barckhausen, U., van den Bogaard, P., Hoernle, K.,
Werner, R., Whittaker, J. M., and Müller, R. D., 2012.
Constraining the Jurassic extent of Greater India: tectonic evolution of the West Australian margin. Geochemistry, Geophysics,
Geosystems, 13, Q05W13.
Gibbons, A. D., Whittaker, J. M., and Dietmar Müller, R., 2013. The
breakup of East Gondwana: assimilating constraints from Cretaceous ocean basins around India into a best-fit tectonic model.
Journal of Geophysical Research, 118, 808–822.
Halgedahl, S., and Jarrard, R., 1987. Paleomagnetism of the
Kuparuk River formation from oriented drill core: evidence for
PALEOPHYSIOGRAPHY OF OCEAN BASINS
647
plate causing the opening of the Cayman Trough
(Figure 3j, k). Subduction of Atlantic Ocean crust is
observed along the Lesser Antilles Trench.
Ocean gateways
The present-day oceanic realm is divided into numerous
large ocean basins, the Pacific being the largest. Each of
these ocean basins is surrounded by continental areas
and connected to neighboring oceans via narrow, shallow,
and diffuse connections, called oceanic gateways. These
oceanic gateways are focal points for the large-scale
exchange of heat, water, salinity, and genes between the
oceans and play a major role in influencing global climate,
ocean circulation, and species diversity. The most wellknown examples of ocean gateways include the Tasman
Gateway, Drake Passage, Fram Strait, Panama Isthmus,
Greenland–Scotland ridge, Tethyan Seaway, and Indonesian Throughflow. Their shape, size, and depth change
over geological timescales and are largely controlled by
large-scale lateral and vertical motions of the many blocks
and basins that form during protracted periods of continental breakup and extension (or collision, uplift, and
shortening during oceanic gateway closure). Global ocean
basin reconstructions, such as those presented in Figure 3,
provide a broad basis for assessing the opening and closure of deep-water ocean gateways through time and thus
how plate tectonic movements influence global climate
and oceanography. The physiographic reconstructions
presented here highlight the timing of separation or amalgamation of continental blocks, assuming these areas to be
rigid features. However, we know that extensive deformation occurs over protracted periods at plate boundaries.
Therefore, the detailed evolution of many gateways such
as the Drake Passage, the Tasman–Antarctic Passage,
and the Panama gateway is dependent on understanding
the subsidence history of submerged fragments of continental crust or volcanic arc fragments (Lawver et al.,
2011). These are not included in the reconstructions
presented in Figure 3.
Ocean basin physiography and the age-area
distribution of ocean floor through time
Ocean basin reconstructions from 200 Ma to the present
imply that old mid-ocean ridge flanks in the proto-Pacific
and the Tethys oceans are gradually destroyed between
200 and 150 Myr ago, while new mid-ocean ridge systems
are initiated in a stepwise fashion between the late Jurassic
and early Cretaceous. This cycle leads to a substantial
younging of the ocean basins from the Jurassic to the Cretaceous period, followed by a gradually aging of the oceanic lithosphere from the Cretaceous seafloor spreading
pulse to the present day (Figure 4). The age-area distribution of ocean crust from 200 Ma to the present day implies
a mid/late Cretaceous sea-level high linked directly to the
transition from supercontinent stability to initial and
mature dispersal, first creating many new mid-ocean
ridges and flanks, which later experience stepwise subduction (Müller et al., 2008b). These cycles can also be linked
with long-term fluctuations in seawater chemistry, leading
to alternations between so-called aragonite and calcite
seas (Müller et al., 2013).
Summary and conclusions
Complete reconstructions of the physiogeography of the
ocean basins, starting with the breakup of Pangaea, have
only been achieved recently for the first time, reflecting
the difficulties involved in recreating now vanished ocean
basins and assimilating many types of geological and geophysical observations into complete models through time.
Although these ocean physiogeographic reconstructions
are limited as they only account for broad-scale processes,
they do provide an essential framework for creating
boundary conditions for understanding ocean circulation,
sediment accumulation, and ocean chemistry through
time, as well as paleoclimate and long-term sea-level fluctuations. Further studies on refining global plate motions
within a deforming plate framework as well as accounting
for vertical motions associated with areas of continental
breakup and collision will lead to more accurate reconstructions of ocean basins.
Bibliography
Afonso, J., Zlotnik, S., and Fernández, M., 2008. Effects of compositional and rheological stratifications on small-scale convection
under the oceans: Implications for the thickness of oceanic lithosphere and seafloor flattening. Geophysical Research Letters,
35, L20308.
Alvey, A., Gaina, C., Kusznir, N., and Torsvik, T., 2008. Integrated
crustal thickness mapping and plate reconstructions for the high
Arctic. Earth and Planetary Science Letters, 274(3–4),
310–321.
Atwater, T., 1970. Implications of plate tectonics for the Cenozoic
tectonic evolution of western North America. Geological Society
of America Bulletin, 81, 3513–3536.
Coffin, M. F., Duncan, R. A., Eldholm, O., Fitton, J. G., Frey, F. A.,
Larsen, H. C., Mahoney, J. J., Saunders, A. D., Schlich, R., and
Wallace, P. J., 2006. Large igneous provinces and scientific
ocean drilling: status quo and a look ahead. Oceanography,
19(4), 150–160.
Colpron, M., Nelson, J. A. L., and Murphy, D. C., 2007. Northern
Cordilleran terranes and their interactions through time. GSA
Today, 17(4), 4–10.
Cox, A., and Hart, B. R., 1986. Plate Tectonics: How It Works. Boston: Blackwell Science Inc. 400 pp.
Crosby, A. G., and McKenzie, D., 2009. An analysis of young ocean
depth, gravity and global residual topography. Geophysical
Journal International, 178(3), 1198–1219.
Gibbons, A. D., Barckhausen, U., van den Bogaard, P., Hoernle, K.,
Werner, R., Whittaker, J. M., and Müller, R. D., 2012.
Constraining the Jurassic extent of Greater India: tectonic evolution of the West Australian margin. Geochemistry, Geophysics,
Geosystems, 13, Q05W13.
Gibbons, A. D., Whittaker, J. M., and Dietmar Müller, R., 2013. The
breakup of East Gondwana: assimilating constraints from Cretaceous ocean basins around India into a best-fit tectonic model.
Journal of Geophysical Research, 118, 808–822.
Halgedahl, S., and Jarrard, R., 1987. Paleomagnetism of the
Kuparuk River formation from oriented drill core: evidence for
PALEOPHYSIOGRAPHY OF OCEAN BASINS
647