Shell marine

Chalk. This is a soft limestone composed mainly of marine shells. 

Taylor, R. E., Slota, P., Fraction Studies on Marine Shell and Bone Samples for Radiocarbon Analyses, In Radiocarbon Dating, pp. 422-432, Berkeley University of California Press, 1979. 

The ostrum of Vitruvius, a beautiful and costly purple color, was obtained from certain marine shell fish. It varies in shade according to the regions where found, being black in the north, as Pontus and Gaul, red in the south as at Rhodes, and blue or violet in the intermediate regions. The shellfish are collected and broken with iron tools, and the purple fluid exudes. On account of its saltness, it soon dries up unless honey is added to it. Large quanti-... 

Marine shell beads are a regular component of the Holocene archaeological record in many areas of the world. Although they rarely outnumber more common artifacts, such as flaked stone and ceramics, they are sufficiently ubiquitous to have been the subject of considerable archaeological research. Such studies focused on both the symbolic aspects of beads (e.g., wealth display) and the reconstruction of prehistoric trade and/or exchange systems. 

Despite the potential to track the spatial movement of marine shell beads, archaeometric attempts at sourcing have been minimal. We are aware of only three other groups that have taken this approach including a neutron activation analysis (NAA) of Busycon sp. shells and artifacts in the American Southeast (/), the use of strontium isotopes as a measure of geologic age of fossil shells in Southwest Europe (2), and the use of oxygen isotope ratios to source Sporufylus sp. beads in Central Europe (5). 

Nelson, R. S. Hohokam Marine Shell Exchange and Artifacts Arizona State Museum Archaeological Series 179, Arizona State Museum, Tuscon, AZ, 1991. 

Other Auxiliaries. The inlet feed coolers are conventional marine shell and tube heat exchangers, three in each bank. One bank is counterflow to the brine and the other is counterflow to the product water. Final temperature approach is in the order of 10° F. 

Figure 6. Radiocarbon content of modern pre-bomh marine shell from the west coast of North and South America, Data from Refs. 73 and 74. Values have been expressed with respect to 0.95 NBS oxalic acid standard and corrected in light of their values.

An examination of Figure 6 also illustrates other problems with marine shell samples. Four samples from the environment of the Galapagos Islands ranged from a little more than —4.0% to a little less than +0.5%. This equates to an apparent variation of ca. 850 years between... 

Table I. Paired Terrestrial Organics/Marine Shell Samples from the West Coast of North America...

It is important to emphasize that a discussion of the problems associated with marine shell could be repeated for any sample type/geo-chemical environment where the contemporary radiocarbon values may not be in equilibrium with the atmosphere. In such cases, a specific contemporary standard must be used for each sample type or geochemical environment which can be related to the terrestrial biological radiocarbon standard. Special standards and/or correction values would, for example, be required for specifically defined oceanographic regions in the case of marine shell, standards for specific fresh water shell or gastropod geochemical environments, standards for Arctic and Antarctic specimens, and specific soil carbonate environments (75). 

Marine shells have been studied in this manner by obtaining analyses on the inner and outer portions of the same shell to study pos-... 

Taylor, R. E., Berger, R., "Radiocarbon Content of Marine Shells from... 

TYRIAN — This Colour or Dye, derived from certain Marine Shells on the Coast of Tyre, has been utilised by the adepts as an emblem of the Red State of their Magistery. Compare Theriaca in Rulandus. 

In addition to the residential area, there was a cemetery at the Black Earth site. At least 154 burials were found, sometimes buried with artifacts and other materials. A number of exotic items were found in addition to the local raw materials. One perforated disk of marine shell, probably from the Atlantic Ocean or the Gulf of Mexico, was found around the neck of a buried infant. A copper wedge from the Great Lakes area had been placed at the top of the neck of the skeleton, perhaps as a substitute for the missing skull of this particular individual. These materials had come from hundreds of miles distant to be buried at the Black Earth site. 

Archaeological investigations at Cerro Narrio had revealed marine shell ornaments... 

Fig. 1 The oxygen isotopic composition of carbonate mollusk shells from the Aral Sea [15]. (1) clayey mud (2) clayey-silty mud (3) sand (4) marine shell debris (5) freshwater shell debris (6) peat (7) plant debris (8) gypsum (9-10) boundaries [(9) gradual (10) sharp)] (11-12) stages [(11) transgressive (12) regressive)]...

Fig. 3 Stratigraphic scheme of the upper Quaternary and Holocene deposits of the Aral Sea (according to [16]). (1) Clayey mud (2) silty-clayey mud (3) clay (4) sand (5) rubble (6) marine shell debris (7) freshwater shell debris (8) peat (9) plant dehiis (10) gypsum (11) sharp contacts (12) gradual contacts...

Finally, carbonate cements reveal the sources of dissolved carbon in the evolving pore waters of the San Joaquin basin. The clastic-rich basin is free of carbonate rocks but contains a considerable amount of organic matter, both in fine-grained sediment and as relatively recent hydrocarbon accumulations. Potential carbon sources for the carbonate cements are marine shell tests, thermogenesis and, possibly, organic reactions related to the presence of the oil. 

MangerudJ. (1972) Radiocarbon dating of marine shells, including a discussion of apparent ages of Recent shells from Norway. Borens 1, 143-72. 

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