The St. Francois Mountains igneous complex of Proterozoic age consists of hypabyssal, granite plutons intruded into the overlying rhyolites of similar age. Melting and crystallization models of these rocks suggested by the field, petrographic, and major element contents are further refined using Rb, Ba, Sr, REE (rare‐earth element), Th, Sc, and Co contents. There are two groups of relatively undifferentiated plutons associated with the Butler Hill caldera and Taum Sauk area that could have formed by partial melting of lower crustal rocks. The plutons associated with the Butler Hill caldera (Knoblick and Silvermine granites) could have formed by about 30% aggregate melting of a quartz diorite, graywacke, or subgraywacke. The plutons associated with the Taum Sauk area could have formed by about 30% equilibrium melting of a subarkose or arkose. More silicic rocks of the Butler Hill caldera could have formed by fractional crystallization. The Silvermine granite is internally zoned. Crystallization of plagioclase/biotite/hornblende/magnetite/apatite/zircon/sphene in a ratio of 0.70/0.10/0.15/0.04/0.005/0.003/0.007 from the least differentiated portion of the Silvermine granite could have formed intermediate portions of the Silvermine. Further crystallization of the Silvermine requires more biotite (Ba begins to decrease) and less hornblende, zircon, and sphene (HREE increase) to precipitate and form the most differentiated portions. Also fractional crystallization of undifferentiated Silvermine‐type magmas could have produced the sequence of Butler Hill‐Breadtray‐Graniteville granites as residual liquids, respectively. The early crystallizing mineral assemblage is dominated by plagioclase and biotite, while the late crystallizing mineral assemblage is dominated by quartz, K‐feldspar, and lesser plagioclase. The Gneissoid granodiorite in the Hawn Park area has the mineral assemblage and composition of a cumulate derived from the Silvermine granite‐type differentiation sequence. The associated volcanic rocks could not have formed from melts of exactly the same composition of any of the associated intrusive rocks. Rather, the volcanic rocks formed from melts of slightly different chemistry.
The paper demonstrates that the motivational concepts underlying the Zeigarnik effect pertaining to individuals attempting to achieve their personal goals can be applied to individuals who are working to attain the group goals. However, this is true only for individuals in cohesive groups as opposed to noncohesive groups.
Twenty-four monitoring wells were drilled and completed in December 1994 as part of a water ar~I mass balance study for the shallow perched aquifer in the Mortandad Canyon alluvium and in the lower part of Ten-Site Canyon. The wells penetrated the alluvium containing the aquifer and were completed into the top of the weathered tuff. Twelve of these wells encountered the Tshirege Member (Cooling Unit lg) of the Bandelier Tuff below the canyon alluvium, while ten wells made contact with the Cerro Toledo interval, which lies between the Tshirege and Otowi Members of the Bandelier Tuff. The remaining two wells were completed into the alluvium above the weathered tuff contact. These wells provide access for continuous water level measurement and water sampling. Data from these new wells will be used to determine changes in alluvial aquifer water storage, water quality sampling, and estimation of seepage into the unsaturated Bandelier Tuff below the alluvium. This report documents drilling activities and well completion logs for the water and mass balance study. These wells also provide critical new data for fourteen north-south vertical cross-sections constructed for the canyon alluvium.
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