Geochemical mass balance

Bulk rock chemistry of hydrothermally altered midoceanic ridge basalt has been well studied and used to estimate the geochemical mass balances of oceans today (Wolery and Sleep, 1976 Humphris and Thompson, 1978 Mottl, 1983). In contrast, very few analytical data on hydrothermally altered volcanic rocks that recently erupted at back-arc basins are available. However, a large number of analytical data have been accumulated on the hydrothermally altered Miocene volcanic rocks from the Green tuff region in the Japanese Islands which are inferred to have erupted in a back-arc tectonic setting (section 1.5.3). 

Freyssinet, P. Farah, A.S. 2000. Geochemical mass balance and weathering rates of ultramafic schists in Amazonia. Chemical Geology, 170, 133-151. 

Albarede, F. Provost, A. (1977). Petrological and geochemical mass balance an algorithm for least-squares fitting and general error analysis. Comp. Sci., 3, 309-26. 

Veibel, M. A. (1985), "Geochemical Mass Balances and Weathering Rates in Forested Watersheds of the Southern Blue Ridge", Am. J. Sci. 285, 904-930. 

Rates of Feldspar Weathering in Natural Weathering Profiles from Geochemical Mass Balance of Small Watersheds... 

Geochemical mass balance studies (also known as input-output budgets) invoke a simple conservation-of-mass principle. If the flux of any element leaving a watershed (e.g., via streams), and the flux of that element into the watershed (e.g., via atmospheric precipitation) are known, the difference between the two can be calculated, and this difference must be due to the sum of all reactions and transformations involving that element which took place within the watershed. Pioneering mass balance studies on weathering profiles and/or small watersheds include those of Garrels and Mackenzie (,51, 52) and Cleaves and Bricker and their... 

Rates estimated in the above studies are shown in Table I. Watershed-scale geochemical mass balance studies yield calculated feldspar weathering rates one to three orders of magnitude slower than rates determined in laboratory experiments. 

An interesting implication of the Toth-Freeze-Witherspoon model is the deep penetration of surface water into the basin over geologic time. This has been used to derive a geochemical mass balance model for the mixing of surface water and diagenetically modified sea water in the Western Canada sedimentary basin using deuterium as a tracer (204). 

Price JR, Velbel MA, Patino LC (2005) Rates and time scales of clay-mineral formation by weathering in saprolitic regoliths of the southeren Appalachians from geochemical mass balance. Geol Soc Am Bull 117 783-794... 

Li Y-H. (1972) Geochemical mass balance among lithosphere, hydrosphere and atmosphere. Amer. J. Sci. 272, 119-137. 

The crust is the Earth s major repository of incompatible elements and thus factors prominently into geochemical mass-balance calculations for the whole Earth. For this reason, and to understand the processes by which it formed, determining the composition of the continental crust has been a popular pursuit of geochemists from the time the first rocks were analyzed. 

Because mass balance is simply an accounting of the flux of material into a system minus the flux of material out of the system, the geochemical mass-balance approach is well suited to interpreting weathering reactions in watersheds (catchments) and in other environmental settings... 

Sverdrup (1990) and Sverdrup and Warfvinge (1995) developed Ae PROFILE model to calculate mineral weathering rates by means of a geochemical mass-balance procedure. This model differs from the others in that it uses dissolution constants, which were, for the most part, determined in the laboratory. Empirical fitting parameters, such as surface area of mineral exposed, are used to adjust the model to the real system being described. The model appears to work satisfactorily in many catchments if the fitting parameters are chosen judiciously. This requires a considerable amount of knowledge... 

O Brien A. K., Rice K. C., Bricker O. P., Kennedy M. M., and Anderson R. T. (1997) Use of geochemical mass balance modelling to evaluate the role of weathering in determining stream chemistry in five Mid-Atlantic watersheds on different lithologies. In Water Quality Trends and Geochemical Mass Balances Advances in Hydrologic Processes (eds. N. E. Peters, O. P. Bricker, and M. M. Kennedy). Wiley, New York, pp. 309-334. 

Velbel M. A. (1992) Geochemical mass balances and weathering rates in forested watersheds of the southern Blue Ridge III. Cation budgets and the weathering rate of amphibole. Am. J. Sci. 292, 58-78. 

Sediment diagenesis reactions cause sources and sinks that are of global importance to the geochemical mass balance of manganese and some other metals sensitive to redox changes. 

Geochemical mass balance dissolved chemical inflow and outflow from the ocean... 

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