Quartz monzonite samples

The quartz monzonite samples (U15E-7 and U15E-7a) were originally composed of 70-80 percent feldspar, 10-15 percent biotite, 3-8 percent quartz, and 2-8 percent opaques. Both samples have been hydrothermally altered U15E-7a being the more altered. The original feldspars in both samples have been sericitized and/or altered to clinozoisite. Secondary cal cite also occurs in both samples. Pyrite is an abundant secondary mineral and minor amounts of both epidote and chlorite replace biotite and fill fractures. 

Figure 11. Percentage of initial concentrations of tracers left in solution as function of time for the sorption experiments with the quartz monzonite samples. C)> U O, Np (Jk), Pu Am (O), Cm.

Figures 10, 11 and 12 show the results of the contact experiments for the basalt, shale and quartz monzonite samples. The rate of adsorption was rapid during the first two weeks and changed slowly thereafter. In these experiments Pu, Am and Cm exhibited behavior similar to the results obtained in the blank experiments. Uranium showed moderate adsorption ( 50 percent) on the basalt but only slight adsorption (10-20 percent) on the shale and quartz monzonite wafers. Neptunium showed strong adsorption (70-80 percent) on the shale and slight adsorption ( v 10 percent) on the basalt and quartz monzonite.

Data confirm the general tendency of an increase of thermal conductivity with increasing quartz content. Roy et al. (1981) derived a correlation between thermal conductivity and quartz content of 100 granite and quartz monzonite samples... 

Rock Samples. Three rock types were selected as substrates basalt from the Umtanum unit in the Pasco Basin in Washington state, quartz monzonite from the Climax Stock of the Nevada Test Site, and shale (metashale) from the Eleana Formation of the Nevada Test Site. Since both the basalt and the quartz monzonite exhibited different kinds and amounts of alteration within the same rock type, two samples from each rock type were used in the experiments. However, there was insufficient material to study the interaction of the more altered of these rock types with all five actinides, therefore, only the interaction with Pu was studied. 

In order to produce an aqueous solution which fulfills these criteria, 120 g each of basalt, quartz monzonite, and shale were ground to powders less than 37 m in diameter. Each of the samples was placed in two liters of distilled-deionized water which had been pre-equilibrated with an atmosphere containing 10 percent CO2, 90 percent Ar, and 10 ppm Og. The experiment was carried out in an inert atmosphere box at room temperature (26 + 2°C). Samples of the fluid (10 ml) were extracted at various times over a 35-day period and filtered (O.OSpm). Analyses for Na, K, Mg, Ca, Fe, Al, Si02 (aq). Eh, and pH were made on each sample. The experiment was terminated at the end of 846 hours and analyses for HCO3, SO4, and Cl were made on each of the fluids. 

Average composition of perennial springs in quartz monzonites and granodiorites of the Sierra Nevadas (56 samples). 

The date is strongly controlled by a sample of phyllite that has a high Rb/ Sr ratio of 19.07 0.29 and was collected from a xeno-lith within the South Quartz Monzonite at Lonely Ridge. Therefore, the date refers to the time at which the granite host-rock cooled sufficiently to allow radiogenic Sr to accumulate in the xenolith... 

Fig. 6.11 Rb-Sr age determination of whole-rock samples of the South Quartz Monzonite from the southwest wall of Cottonwood Canyon (506, 511), from Windy Ridge (507, 508, and 509), and from South Ridge (513) of the Nilsen Plateau (Fig. 6.5). The date and initial " Sr/ Sr ratio were calculated by Eastin (1970) by the methods of York (1966, 1969) and have been adjusted to >. = 1.42 x 10" year h Sample 508 was excluded from the calculation of the Rb-Sr date because it lost radiogenic Sr. Plotted from data by Eastin (1970).

Fig. 7.5 Silica-variation diagram of whole-rock samples of the Wyatt Formation in the Wisconsin Range of the Horlick Mountains. The x represents a sample of the porphyritic quartz monzonite (Data from Minshew 1967 Faure unpublished in Appendix 7.8.1)...

Eastin (1970) also analyzed two samples of biotite granite and three of quartz monzonite from the Thiel Mountains for dating by the Rb-Sr method (Appendix 8.5.3). He used these data to determine the crystallization date of the granite but was unable to fit a straight line to all five data points. Therefore, we excluded a biotite-rich sample of quartz monzonite from Smith... 

Fig. 8.3 The crystallization age of the granitic basement rocks of the Thiel Mountains was calculated from analytical data of Eastin (1970) listed in Appendix 8.5.3. The rock samples were provided by Arthur B. Ford. Solid circles = quartz monzonite open circles = biotite granite. One of the five samples ( 499) analyzed by Eastin (1970) was excluded because it lost radiogenic Sr. The value of the decay constant of Rb used to calculate the date from the slope of the isochron was A = 1.42 x 10 " year A The slope and intercept of the isochron were determined by unweighted linear regression...

Range (avg. of 12 samples) K-feldspars from Butte Quartz Monzonite and related rocks K-feldspars, Ringing Rocks pluton, Boulder batholith 17.87-18.17 (17.98) 15.54-15.65 (15.60) 38.11-38.46 (38.23) Doe et al (1968)"... 

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