Stratigraphic evidence

The maximum burial depths of the Miocene succession were estimated to be between 200 and 700 m (Milliken et al., this volume), based on variations of the present thickness range of the succession in the study area. Two apatite fission track analyses indicate a burial temperature of 50-55 °C in the Bologna area and 70-75 °C in the Vetto-Carpineti turbidites (Boettcher McBride, 1993). The latter sample was buried slightly deeper than the first one, but neither is reset in terms of the fission-track data. Fission-track results are not conclusive, considering the poorly defined palaeogeothermal gradients, and can involve some underestimation of the maximum burial depths. Nevertheless, based on tectonic and stratigraphical evidence it is unlikely that the succession reached more than 1 km of maximum burial depth. 

In individual deposits, S S of sulfides generally increases stratigraphically upwards (Fig. 1.42). (Kajiwara, 1971). Based on the sulfur isotope evidence, Kajiwara (1971) deduced that the ore solutions underwent a progressive cooling and oxidation due to mixing with seawater. 

Martin, H.A. 1991. Tertiary stratigraphic palynology and palaeoclimate of the inland river systems in New South Wales. In Williams, M.A.I., De Dekker, P., Hershaw, A.P. (eds.). The Cainozoic in Australlia A reappraisal of the evidence. Geological Society of Australia Special Publication, 18, 181-194. 

An initial application of the technique to the Colorado Plateau indicates that although uplift began at least 25 m.y. before present with about 800 m displacement before 5 Ma, the main phase of rapid uplift occurred in the last 5 m.y., with an additional 1100 m since then. This suggests an early uplift rate of 40 m/m.y. and a recent rate of 220 m/m.y. With the available data, it is not possible to distinguish between a smooth curve (as drawn in Fig. 11) and a sudden increase in uplift rate between 9 and 5 Ma. However, the uplift curve for the Colorado Plateau (Fig. 11) resolves the controversy between the different interpretations of various other proxies. The early and recent uplift camps are reconciled by this analysis in that the stratigraphic and geomorphologic evidence for early activity is accommodated, while the evidence for rapid recent uplift is also consistent with our results. 

This chapter reviews research on the abundance of sulfur in major coal basins in the U.S., the forms of sulfur in coals, the distribution of sulfur in coal lithotypes and macerals, and the nature of sulfur-containing organic compounds in coal. Next, the origin of sulfur in coal is reviewed based on the evidence from the distribution and speciation of sulfur in peat, and from stratigraphic, isotopic, and trace element data. Finally, the origin of sulfur in coal is explained by a geochemical model. 

The trace element compositions of the four major cement zones are shown in Figure 8.28 and Table 8.5. It is evident that each zone is chemically distinct. Zone 1 is rich in Mg and poor in Mn and Fe Zone 2 is rich in Mn and has intermediate concentrations of Mg and Fe Zone 3 is poor in all three trace elements and Zone 5 is rich in Fe and Mg and has intermediate concentrations of Mn. These trace element differences account for the luminescence differences among the cement zones. The distinct chemical signature of each zone supports the petrographic evidence that each zone records a regionally extensive cementation event in a distinct meteoric water chemistry. If the zones were lateral equivalents of each other rather than separate time-stratigraphic events, one would anticipate considerable overlap between the zonal cement chemistries. 

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