Geological systems formation

E. P. Katsanis, P. H. Kmmrine, and J. S. Ealcone, Jr., "Chemistry of Precipitation and Scale Formation in Geological Systems," SPE preprint 11802, National Symposium on Oil Field and Geothermal Chemisty, Denver, Colo., June 1, Society of Petroleum Engineers, 1983. 

Example 9.15 Long-term asymptotic solution of reversible reaction diffusion systems The formation of dynamic reaction-diffusion fronts occurs when two species A and B are uniformly distributed on opposite sides of an impenetrable barrier, which is removed at time t 0 at isothermal conditions. The species A and B start to diffuse and react upon mixing, and produce species C. This creates a dynamic reaction front, and the spatio-temporal evolution of this front may exhibit some unique features, which may be valuable in understanding many phenomena in physical, chemical, biological, and geological systems. The long-term behavior of this reversible reaction-diffusion system was studied by Koza (2003). 

Early life most likely depended on exploiting the transient redox contrasts available from two sources within the inorganic geological system— especially at hydrothermal vents (Reysenbach and Shock, 2002) and secondly from inorganic light-driven reactions, such as the formation of transient oxidizing and reducing species in the atmosphere by incident radiation. 

Thus far in this discussion, these fluid-filled formations of Florida have been considered as part of a geologic system, a hydrologic system, and as a coexisting geochemical system. It would seem desirable to combine the results of the various natural processes into one unifying concept. 

Water in well-characterized pores is a system of general interest because it serves as model system for the non-bulk or inhomogeneous water that is ubiquitous in biological and geological systems, as well as in nano-sfructured materials. Often confined or interfacial water is highly relevant to the properties and functions of entire systems, e.g., those in ion channels and clay minerals. X-ray diffraction studies show that water can fill the inner space of open-ended single-walled carbon nanotubes (SWCNTs) under ambient conditions and freezes into crystalline solids. These are often referred to as ice nanotubes . Ice stmctures in confined systems are characterized as stacked n-membered rings or equivalently as a rolled square-net sheet. The formation of the ice nanotubes in CNTs has also been observed by NMR, neutron diffraction, and vibrational spectroscopy studies. 

In the laboratory, the first rare earth carbonates were synthesized about 100 years ago. Their spectroscopic and thermal properties have been frequently studied and there are a number of studies dealing with complex formation, under normal conditions as well as in geological systems. X-ray structural studies are surprisingly few, obviously due to the difficulties of crystal growth. There are no reviews devoted to the rare earth carbonates alone, but several theses dealing with spedfic aspects of carbonate complexes in solution or in the solid state have recently appeared (Dexpert, 1976 Dumonceau, 1979 Spahiu, 1983). 

It is estimated that the earth s age is in the neighborhood of 4 to 7 billion years. These estimates are basically derived from carbon-14, potassium-40, uranium-235, and uranium-238 dating of earth rocks and meteorites. The meteorites give important data as to the age of our solar system. Geologic time is felt to be represented by the presence of rock intervals in the geologic column (layers of rock formations in vertical depth) or by the absence of equivalent rocks in correlative columns in adjacent locations [25,26]. The two basic factors that are used to determine geologic time are ... 

The geological sciences are involved in studying the naturally occurring materials of the earth and solar system (i) to understand the fimdamental processes of crustal formation on earth and solar system evolution, and (2) to evaluate the crustal materials of potential economic value to man. Prior to the 1930 s, analyses were carried out exclusively using classical analytical techniques, with detection limits on the order of o.oi-o.i % (mass fraction). The number of elements contained in any sample could be as extensive as the periodic table, but very few of these could be determined. The development of instrumental techniques revolutionized the analysis of geochemical samples, beginning in the 1930 s. 

Roy, W.R., Mravik, S.C., Krapac, I.G., Dickerson, D.R., and Griffin, R.A., Geochemical Interactions of Hazardous Wastes with Geological Formations in Deep-Well Systems, Environmental Geology Notes 130, Illinois State Geological Survey, Champaign, Illinois, 1989. 

The geological process of the formation of serpentine from peridotite probably involves the synthesis of carbon compounds under FTT conditions (see Sect. 7.2.3). The hydrogen set free in the serpentinisation process can react with CO2 or CO in various ways. The process must be quite complex, as CO2 and CO flow through the system of clefts and chasms in the oceanic crust and must thus pass by various mineral surfaces, at which catalytic processes as well as adsorption and desorption could occur. 

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