Lakes tectonic

Martel, E., Van Breemen, O., Berman, R.G., Pehrsson, S. 2007. Geochronology and, tectonometamorphic history of the Snowbird Lake area. Northwest Territories, Canada New insights into the architecture and significance of the Snowbird tectonic zone. Precambhan Research, in press. 

The Wollaston and Mudjatik domains form two of the major subdivisions of the Cree Lake Zone (Lewry Sibbald 1977), and also the eastern part of the western foreland of the Paleoproterozoic Trans-Hudson Orogen (i.e., part of the Hearne Province Hoffman 1989, 1990 Bickford et al. 1990 Lewry Collerson 1990). The present tectonic configuration resulted from the oblique collision of the Superior Province into the accreted Reindeer Zone and Hearne Province during the Hudsonian Orogeny (Fig. 2). 

Vulsini 0.6 to 0.15 - Several multicentre volcanic complexes with calderas, developed around the volcano-tectonic depression of the Bolsena Lake. Dominant pyroclastic fall deposits and ig-nimbrites and minor lavas, showing KS (trachybasalt to trachyte) and HKS (leucitite and leucite tephrite to pho-nolite) compositions. Minor melilitite. 

Water levels in the oceans were lower by over 150 m during the ice ages, and similar water level fluctuations occurred in lakes and inland seas due to climatic changes and tectonic events. The sea level changes influenced the near-shore regions in the following ways ... 

Piercey S. J., Mortensen J. K., Murphy D. C., Paradis S., and Greaser R. A. (2002) Geochemistry and tectonic significance of aikalic mafic magmatism in the Yukon-Tanana terrain, Finlayson Lake region, Yukon. Can. J. Earth Sci. 39, 1729-1744. 

SaUne lakes are important environmental features, with significant geochemical impacts on ecology, water resources, and economic activity around the world. Ancient sediments within saline lake basins also offer important sedimentary archives of past climates and tectonics, because such deposits can record significant hydrologic variations. 

Schneider D. A., Bickford M. E., Cannon W. F., Schulz K. J., and Hamilton M. A. (2002) Age of volcanic rocks and syndepositional iron formations, Marquette range supergroup implications for the tectonic setting of Paleoproter-ozoic iron formations of the Lake Superior region. Can. J. Earth Sci. 39, 999-1012. 

Lake, S.D.. Karner, G.D. (1987) The structure and evolution of the Wessex Basin, southern England an example of inversion tectonics. Tectonophysics, 137, 241-218. 

Table 5. Helium fluxes, C/ He and heat/ He ratios in lakes located in volcanic or tectonically active regions (extended from Aeschbach-Hertig et al. 1996b).

Alluvial fans cut by tectonic faults can also yield information on the frequency of earthquakes. An offset debris flow fan in Owens Valley (California) was dated with °Be by Bierman et al. (1995). Based on boulder ages from different parts of the flow and the record of three faulting events, the authors deduced earthquake recurrence intervals of 5800-8000 years for that location. Zreda and Noller (1998) measured C1 in a bedrock fault scarp at Hebgen Lake (Montana) and were able to extract the ages of six prehistoric... 

Initial heat flow, Q, is estimated from the present-day values of surface heat flow in the regions with tectonic settings similar to that expected for the time of the basin initiation. For example, Q s 100-110 mW m" is typical of continental rift areas (Baikal Lake, African rift system) however, on rift shoulders, Q can be nearly 65-85 mW (Smirnov 1980). Estimations of the initial heat flow can be adjusted by analysis of variations in tectonic subsidence of the basement (see following sections). In the case of the Oued el-Mya Basin, Q is approximately 52 mW m" (Fig. 6.5). 

A tremendous range of paleoenvironmental information can be gained from an assessment of each of these three basic mineral components of lake sediments. Much of this vast literature has been summarized and reviewed in Talbot Allen (1996), Smoot Lowenstein (1991), Rodriguez-Clemente Tardy (1987), Hakanson Jansson (1983), Dean Touch (1983), Eugster Kelts (1983), Watson (1983a, b). Dean (1981), Eugster Hardie (1978), Kelts Hsti (1978), Jones Bowser (1978), Hardie et al. (1978) and Reeves (1968). Detrital minerals reflect the interaction of several factors (i) tectonic... 

Olsen, P. E., 1990. Tectonic, climatic, and biotic modulation of lacustrine ecosystems — examples from Newark Supergroup of Eastern North America. In Katz, B. J. (ed.) Lacustrine Basin Exploration, Case Studies and Modern Analogs. AAPG Memoir 50, Tulsa, Ok 209-224. Ordonez, S. M. dc L. es Garcia del Cura, 1994. Deposition and diagenesis of sodium-calcium sulfate salts in the Tertiary saline lakes of the Madrid Basin, Spain. In Renaut, R. W. W. M. Last (eds.) Sedimentology and Geochemistry of Modern and Ancient Saline Lakes. SEPM Spec. Pub. No. 50 229-238. 

Cohen, A. S., K.-E. Lezzar, I. J.Tiercelin M. Soreghan, 1997. New palaeogeographic and lake-level reconstructions of Lake Tanganyika implications for tectonic, climatic and biological evolution in a rift lake. Basin Res. 9 107-132. 

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