Proposed facies

In 1966, Seki (36) proposed a new facies, the wairakite facies, characterized by the occurrence of wairakite-quartz with clay minerals, in the absence of prehnite or pumpellyite. On field, experimental, and thermodynamic grounds, this proposed facies evidently represents, at least for conditions where PH2o = Pfiuid, higher temperatures than the laumontite assemblages, and relatively low pressure. Subsequently, Seki (35) introduced separate mordenite, heulandite, and laumontite facies. Our earlier definition of the zeolite facies was intended to be broad... 

A consideration of natural occurrence and chemical composition of alkali zeolites allows a certain refinement of the zeolite facies concept previously proposed. The key factor is the grouping of the alkali zeolites into a continuous solid solution series. Other possible coexisting phases of similar composition are sodium and potassium feldspar, natrolite and analcite. The extent of solid solution decreases with temperature, possibly also with pressure. This effect allows the sequential series zeolite-K feldspar, zeolite-analcite-K feldspar, analcite-K feldspar-albite and eventually two feldspars to the exclusion of analcite, the alkali zeolite with the highest stability limits. 

The relative amounts of the extended hop-17(21)-enes (Figure 3e) and, especially, the relative concentrations of the C35 homologue (Figure 3f) show some sudden changes at the facies boundaries. It has been proposed (33-35) that this relative abundance of C35 extended hopenes (Facies B) reflects a hypersaline palaeoenvironment. Others consider this the typical distribution of the extended hopenes in anoxic marine sediments (32). 

The concentrations of the total alkylthiophenes (except thiophene hopanoids) in the bitumens show a depth profile somewhat similar to that of the total sulfur content (cf. Figures 6a and Id). The high concentrations of alkylthiophenes in Facies B compared to A and C are consistent with the proposed incorporation of inorganic sulfur species into specific funtionalised lipids in anoxic marine environments (6-12). 

Dorr (1973) proposed that the Caue Itabirite BIF (Brazil) was deposited in stable near-shore or miogeosynclinal conditions and was interbedded with thick layers of dolomite, and that in the upper part of the section of the Minas series, where carbonate and discontinuous oxide facies were de-... 

Calculations such as those by Morse and Mackenzie (1990) indicate that the calcite saturation depth is generally —1 km greater than proposed by Berger (1977) and that it is much greater than R. It appears only loosely related to the FL. In the equatorial eastern Atlantic Ocean, FL is —600 m shallower than the saturation depth. If these observations are close to correct, the long cherished idea of a tight relation between seawater chemistry and carbonate depositional facies must be reconsidered (Mekik et al., 2002). The influence of near interfacial diagenetic processes on these relationships is discussed in the next section. 

To end up this Section, we consider now an alternative ASC approach which strongly deviates from the basic set up previously discussed. The quantum system, the solute , has been considered immersed in a continuum solvent distribution characterized, pritna facie, by its dielectric response function. Klamt and Schuiirman (1993) propose to replace the dielectric response function with the response function of a liquid electric conductor (the so-called COSMO model). In doing so, one has other electrostatic problems, with simpler boundary conditions. In fact, for a system of charges (the solute) in a screening conductor (where = oo), the electro-... 

In 2000, again after some wrong turns, the FERC mandated that pipeline companies price new or expanded services on an incremental basis. Setting incremental pricing as the default rule for new pipeline construction put an end to the fight over traditional certification. If a pipeline company approached the Commission with a new proposal, it was no longer required to demonstrate connected gas supplies. With a portfolio of letters of intent from committed incremental shippers, the Commission had virtual prima facie evidence of economic need. The typical time period needed to plan and construct a typical large-scale pipeline expansion project dropped from five years to two. "... 

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