Features of Note
Lake Baikal
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Lake Baikal is situated in Russia, directly on the plate boundary between the Eurasian and Amurian plates, known as the Baikal Rift Zone. It is about 34,000km^2, with a maximum depth of 1642m (Intas Project 99-1669, 2002), resulting in a volume greater than that of all the great lakes combined. It formed as the result of rifting between the two plates, producing what is currently the deepest lake on Earth. The origin of the rift is still under debate. Some believe it was a product of India's collision with Asia (Molnar et al. 1975), while others believe an anomaly in the upper mantle below the Eurasian plate initiated rifting (Gao et al. 1994). The age of the rift basin is difficult to constrain; deposits in Southern Baikal typical of shallow basins have been dated at ~27 million years old, while deposits to the north are somewhat younger (~5 million years), indicating initial rifting to the south (Hutchinson et al., 1992.) Due to its age, the ecosystem has had time to evolve in interesting ways, producing a diverse and unique set of flora and fauna, the majority of which are endemic.
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The Marianas Trench
Perhaps one of the most well-known tectonic features from this area, the Marianas Trench is located on the convergent boundary between the Mariana and Pacific plates. The subduction in this area has produced the deepest trench on Earth, at approximately 11,000m below sea level. This feature is discussed in further detail on the Marianas Plate page.
Click here or here for an interesting scale comparisons of the Marianas Trench.
The Boso Triple Junction
A triple junction is a point at which 3 tectonic plates touch. Tectonic plate boundaries can be convergent (trench, T), divergent (rift, R), or transform faults (transform, F). The Boso triple junction, formed where the Okhotsk, Philippine, and Pacific plates meet, is the only known T-T-T triple junction; all three boundaries are trenches (Ogawa et al. 1989). Research has shown that the current configuration of the plates is unstable, and the triple junction may soon switch to a T-T-F junction (Nitsuma 1996).
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References
Intas Project
99-1669, 2002, http://users.ugent.be/~mdbatist/intas/morphometry.htm
Hutchinson, D. R., A. J. Golmshtok, L. P. Zonenshain, T. C. Moore, C. A. Scholtz, and K. D. Klitgord (1992), Depositional and tectonic framework of the rift basins of Lake Baikal from multichannel seismic data, Geology, 20, 589–592.
Molnar, P. Tapponnier, Cenozoic tectonics of Asia: effects of acontinental collision, Science 189 (1975) 419–426.
S. Gao, P. Davis, K. Liu, P. Slack, Y. Zorin, N. Logatchev, M.Kogan, P. Burkholder, R. Meyer, Asymmetric upwarp of theasthenosphere beneath the Baikal rift zone, Siberia, J. Geophys.Res. 99 (1994) 15319–15330.
Ogawa, Y., Seno, T., Tokuyama, H., Akiyoshi, H., Fujioka, K., and Taniguchi, H., 1989, Structure and development of the Sagami Trough and off-Boso triple junction: Tectonophysics, v. 160, p. 135-150, doi: 10.1016/0040-1951(89)90388-0.
Niitsuma N (1996) The trench-trench-trench triple junction and tectonic evolution of Japan. Geosci Rep Shizuoka Univ 23:1–8
Ogawa, Yūjirō, Ryo Anma, and Yildirim Dilek. Accretionary Prisms and Convergent Margin Tectonics in the Northwest Pacific Basin. Dordrecht: Springer, 2011. Print.
Hutchinson, D. R., A. J. Golmshtok, L. P. Zonenshain, T. C. Moore, C. A. Scholtz, and K. D. Klitgord (1992), Depositional and tectonic framework of the rift basins of Lake Baikal from multichannel seismic data, Geology, 20, 589–592.
Molnar, P. Tapponnier, Cenozoic tectonics of Asia: effects of acontinental collision, Science 189 (1975) 419–426.
S. Gao, P. Davis, K. Liu, P. Slack, Y. Zorin, N. Logatchev, M.Kogan, P. Burkholder, R. Meyer, Asymmetric upwarp of theasthenosphere beneath the Baikal rift zone, Siberia, J. Geophys.Res. 99 (1994) 15319–15330.
Ogawa, Y., Seno, T., Tokuyama, H., Akiyoshi, H., Fujioka, K., and Taniguchi, H., 1989, Structure and development of the Sagami Trough and off-Boso triple junction: Tectonophysics, v. 160, p. 135-150, doi: 10.1016/0040-1951(89)90388-0.
Niitsuma N (1996) The trench-trench-trench triple junction and tectonic evolution of Japan. Geosci Rep Shizuoka Univ 23:1–8
Ogawa, Yūjirō, Ryo Anma, and Yildirim Dilek. Accretionary Prisms and Convergent Margin Tectonics in the Northwest Pacific Basin. Dordrecht: Springer, 2011. Print.
Page created by Matthew Simons. Last edited Jan. 30, 2014.