Granite illustration

Table II summarizes analytical data for dissolved inorganic matter in a number of natural water sources (J3, 9, J 9, 20, 21). Because of the interaction of rainwater with soil and surface minerals, waters in lakes, rivers and shallow wells (<50m) are quite different and vary considerably from one location to another. Nevertheless, the table gives a useful picture of how the composition of natural water changes in the sequence rain ->- surface water deep bedrock water in a granitic environment. Changes with depth may be considerable as illustrated by the Stripa mine studies (22) and other recent surveys (23). Typical changes are an increase in pH and decrease in total carbonate (coupled), a decrease in 02 and Eh (coupled), and an increase in dissolved inorganic constituents. The total salt concentration can vary by a factor of 10-100 with depth in the same borehole as a consequence of the presence of strata with relict sea water. Pockets with such water seem to be common in Scandinavian granite at >100 m depth.

The application of Ge(Li) detectors to the determination of trace elements in rocks is beautifully illustrated by the work of Gordon et al. 6 who were able to determine instrumentally 23 elements in a wide variety of igneous rocks. A useful discussion of sensitivities and potential interferences may also be found in this paper. The Ge(Li) gamma-ray spectrum of thermal neutron irradiated standard granite G—1 as obtained in our laboratory is shown in Fig. 9. Again, the tentative assignment of photopeaks is based... 

We presented two illustrative examples of obtaining input information. The first concerned partitioning of a borehole into domains (rock segments lengths with similar characterisitcs). The second concerned a Test Case in which a 6(X) m x 180 m x 120 granitic rock mass was studied to establish how additional information would influence the estimated rock properties and their variation. 

Surface waters that originate in basins where the major rocks are granite contain very small amounts of dissolved minerals, not more than approximately 30 mg/liter. These are an important group of waters for example, the water supplies of New York City (from the Catskill Mountains), San Francisco and Oakland (from the Sierra Nevada Mountains), Seattle (from the Cascade Mountains), and many rivers and lakes in New England are of this type. They are illustrated by Type A, in Table 1-4,... 

The bulk of the Wisconsin Range Bathohth is composed of foliated and massive porphyroblastic facies. The tourmaline-bearing granite occurs on Savage Nunatak (Fig. 7.6) and is illustrated in Fig. 7.8. The tourmaline occurs in the form of ovoid rosettes up to... 

The first description of the granitic rocks of the basement complex by Long (1961) was illustrated by... 

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