Paleozoic rocks

It is inferred that in the northern part of the province submarine volcanic rocks are thick in the central zone, while at marginal zone it is thin and the Plio-Pleistocene subaerial volcanic rocks are exposed. The vein-type deposits occur widely in the province. The precious vein-type deposits occur in relatively young (Plio-Pleistocene) volcanic rocks, while large base metal vein-type deposits (e.g., Toyoha, Inakuraishi, Ohe) and Kuroko deposits (e.g., Kunitomi) occur in central zone where thick Miocene submarine volcanic rocks are distributed (Figs. 1.149 and 1.150). Small base metal vein-type deposits occur in Paleozoic rocks in the southern part. 

Formations from all geologic periods have been used for deep-well injection, but Paleozoic rocks are used for most injection zones (53%), followed by Tertiary-age formations (39%). Older Paleozoic rocks have been more frequently used for injection primarily because they tend to be more deeply buried. However, the more recent Tertiary-age Gulf Coast sediments are also very thick, and most injection in rocks of this age takes place there. 

Williams, H. 1995. Chapter 4 - Middle Paleozoic rocks. In Williams, H. (ed) Geology of the Appalachian-Caledonide Orogen in Canada and Greenland. Geological Survey of Canada, Geology of Canada Series No. 6, 315-446. 

Neoproterozoic to Early Paleozoic rocks of the Annidale area are interpreted to mark the southeastern margin of Ganderia in the New Brunswick segment of the northern Appalachians (Johnson et al. 2009). The area is underlain by Late Cambrian to Early Ordovician rocks of the Annidale Group and Late Neoproterozoic to Early Cambrian rocks of the Belleisle Bay Group, which are juxtaposed along a major tectonic boundary marked by the Taylor Brook Fault (Fig. 1). 

Distribution of Some Organic Substances in Paleozoic Rocks of Central Pennsylvania... 

Of the substances studied the most abundant in the Paleozoic rocks of the area are furfurals presumably derived from carbohydrates, higher molecular weight hydrocarbons, and in a few samples, amino acids. Acid and base soluble, low boiling substances having some properties of heterocyclic compounds, phenols, and organic acids exist in smaller amounts. 

Bituminous Substances. The distribution of hydrocarbons and other bitumens in some of the Paleozoic rocks of the area is shown in Tables I and II, the latter summarized after Swain (7). The presumed saturated hydrocarbons of the Ordovician, Silurian and Lower Devonian samples are measurably less than in the Middle and Upper Devonian samples. The presumed aromatic hydrocarbons are not as well differentiated. The pyridine-plus-methanol-eluted chromatographic fractions, arbitrarily taken as asphaltic material, also appear, like the aromatic fractions, to be controlled more by local variations than by geologic age. 

Other Organic Substances. Spectral data on other organic substances detected in samples of the Paleozoic rocks treated with dilute hydrochloric acid and distilled, are given in Table VI. The substances possibly represent aromatic and heteroaromatic compounds such as anthracene, naphthalene, pyridines, and phenols, but a more definite characterization has not been completed. The compounds seem to be present in only a few parts per million. 

Table V. Amino Acids Separated Paleozoic Rock Samples...

Offshore neritic formations in the Paleozoic rock sequence probably include, on faunal and lithologic grounds, the Lower Ordovician Beekmantown dolomites, Middle Ordovician limestones, and Devonian Marcellus and Burket black shales (Table III). The first two are characterized by 0.1-0.4% organic carbons, very low organic nitrogen, and about 20 p.p.m. hydrocarbons but no carbohydrate residues. The Devonian offshore neritic black shales by contrast... 

Keith A. Kvenvolden Would you elaborate on your finding of hydrocarbons in acid extracts of Paleozoic rocks ... 

In nature the Fe-rich illites (glauconite and celadonite) appear to progress from the lMd to the 1M polytype. The Al-rich illites are predominantly the lMd and 2M varieties. If the 1M polytype is an intermediate phase, it is surprising that it is not more abundant in sediments. Recent studies of unmetamorphosed Precambrian sediments (Reynolds,1963 Maxwell and Hower,1967) have shown that the lMd polytype is relatively abundant in ancient sediments, particularly in the extremely fine fraction. The senior author has noted the relative abundance of the lMd polytype in the fine fraction of most Paleozoic rocks but has considered most of it to be mixedlayered illite-montmorillonite rather than illite. Weaver (1963a), Reynolds (1965), and Maxwell and Hower (1967) have shown that during low-grade metamorphism water is squeezed from the expanded layers and the lMd polytype is transformed into the stable 2M polytype. 

Pemandez-Suarez J., Gutierrez A. G., Jenner G. A., and Tubrett M. N. (1999) Crustal sources in lower Paleozoic rocks from NW Iberia insights from laser-ablation U—Pb ages of detrital zircons. J. Geol. Soc. London 156, 1065—1068. 

Lapworth C. (1879) On the tripartite classification of the Lower Paleozoic rocks. Geol. Mag. 6, 1-15. 

Outstanding concentrations of n-Ci, n-Cn, and n-Ci in early Paleozoic rocks Gloeocapsomorpha prisca, marine phytoplankton of uncertain affinity, probably an alga identified in Cambrian-Devonian sediments but most prominent in Ordovician. Estonian kukersite is a typical source. Blokker et al. (2001) and Powler (1992)... 

Although dolomite is abundant in Proterozoic and Paleozoic rocks, its relative contribution to more recent carbonate sediments is signibcantly less (Daly, 1909), and it comprises only —10% of modern carbonate sediments (Holland and Zimmerman, 2000). Thus, the precipitation of dolomite. 

Western Boundary Ground-water inflow from Paleozoic rocks ... 

Lee, L., and Goldhaber, M. B., 2001, The distribution ofMVT-related metals in acid insoluble residues of paleozoic rocks in the Ozark plateaus region ofthe United States U.S. Geological Survey Open-File Report, 01-0042, 35 p. 

Hoggar and Reguibat Massifs. Such outcrops are also observed in the monoclinal structures of South-Illizi and Tassili-Najjer in between the thickest development of Paleozoic rocks. 

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