<p>The Sierra Blanca metamorphic core complex (SBMCC), located 90 miles west of Tucson, is part of the southern belt of metamorphic core complexes that stretches across southern Arizona. The SBMCC exposes Jurassic age sedimentary rocks that have been metamorphosed by intruding Late Cretaceous peraluminous granites and pegmatites. Evidence of this magmatic episode includes polysythetic twinning in plagioclase, albite exsolution of alkali feldspar resulting in myrmekitic texture, and garnet, mica and feldspar assemblages. The magmatic fabric is overprinted by a Tertiary (Miocene?) tectonic fabric, associated with the exhumation of the Sierra Blanca metamorphic core along a low-angle detachment fault, forming the SBMCC. The NW-SE elongated dome of metamorphic rocks forms the footwall of the detachment shear zone, and is separated from the hanging wall, composed of Paleozoic and Mesozoic metasedimentary rocks, by a low-angle detachment shear zone. Foliation is defined by gneissic layering and aligned muscovite, and is generally sub-horizontal, defining the dome. The NNW-SSE mineral stretching lineation is expressed by plagioclase and K-feldspar porphyroclasts, and various shear sense indicators consistent with a top-to the-NNW shear sense. Lineation trends in a NNW-SSE orientation; however, plunge changes across the domiform shape of the MCC. Much of the deformation is preserved in the blastomylonitic gneiss derived from the peraluminous granite, including epidote porphyroclasts, grain boundary migration in quartz, lozenged amphiboles, mica fish, and retrograde mineral alterations. Detailed petrologic observation and microstructural analysis indicate deformation temperatures of 450-575 ? ?C presented here provide thermomechanical constraints on the evolution of the SBMCC.

The structure and petrology of Upper Precambrian and Cambrian rocks have been studied in detail, in an area 38 miles north - east of Adelaide, South Australia. The rocks occur within a broad zone of high grade metamorphism on the eastern side of the Mt. Lofty Ranges. The Upper Precambrian succession consists predominantly of pelitic and semi - pelitic schists, quartzites, calc - silicate rocks and calc - schists, and the Cambrian sequence of quartzo - feldspathic schists, migmatites, granite gneiss, calc - silicate rocks and minor pelitic schists and quartzites. The rocks have reached the sillimanite grade of metamorphism and the metamorphism is of the low pressure - intermediate type. Dolerites, pegmatites, minor granodiorites and granites intrude the meta - sediments. Mineralogical and structural relationships of the granite gneiss, indicate that it has been formed by recrystalliaation of the quartzo - feldspathic schists. Small scale metamorphic differentiation, appears to have accompanied the recrystallization. The migmatites are believed to have been formed by metamorphic differentiation rather than by anatexis. Three phases of deformation are recognised in the Upper Precambrian rocks and two in the Cambrian. The second deformation recorded in the Upper Precambrian rocks does not appear in the Cambrian rocks. Each deformation has been accompanied by the formation of foliation. In the Proterozoic rocks deformed by the second and third phases of folding, the foliation is a crenulation cleavage. The deformations in both the Upper Proterozoic and Cambrian sequences are considered to be related. Petrofabric studies of quartz, scapolite and biotite are related to the respective macroscopic structures. An analysis of the chronology of crystallisation and deformation of these rocks indicates that crystallisation continued during and after each phase of deformation. Faulting commenced either prior to or during meta - morphism. Intense metasomatic activity followed a later phase of faulting resulting in the widespread development of albitites and in some cases talc ore bodies. The albitites formed in the fault zone were subsequently brecciated by further movement and later healed by the introduction of more metasoinatic fluid. / Thesis (Ph.D.) -- University of Adelaide, Department of Geology, 1966.

Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains ix, 135 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references (p. 93-95).

<p> The objective of this research was to determine the size, shape, activity of dunes, petrological characteristics, and provenance of sand in the Winnemucca Dune Complex (WDC). Methods and procedures included the extraction of weather records from meteorological stations, generating surficial landform maps, measuring dune advancement from historical aerial imagery, and field sampling of sand for laboratory inspection of grain size and mineralogical composition. Grain size parameters and textural classification of dune sand were determined using a Laser Granulometer and GRADISTAT v.8 (Blott &amp; Pye 2001). The mineralogical composition and physical classification of dune sand was analyzed using fine powder X-ray Diffractometry and stained standard thin sections. Results were plotted on ternary diagrams with Quartz-Feldspar-Lithic (Folk 1974) and Quartz-Alkali feldspar-Plagioclase (Streckeisen 1976, 1978) overlays. </p><p> Measurements from surficial landform maps estimate wind-blown deposits are distributed on 472.2 square kilometers of terrain. Active dunes are universally dominated by unique configurations of intermediate shaped barchan and parabolic dunes. For the purpose of this study these features were termed as barchanbolic. WDC is primarily covered by 6 crescentic complexes, 1 large sand sheet, and discontinuous sets of compound barchanbolic-parabolic dune fields. The crescentic complexes are composed of closely spaced barchanoidal and transverse ridges with occasional star dunes. Between the complexes are repetitive sequences of compound and individual barchanbolic-parabolic dunes that laterally radiate towards the bounding perimeter of WDC. Sand sheets, ramps, climbing, descending, cliff-top, and lee dunes are also present along mountain crests and hillsides. Sand sheets (56.3 square kilometers) and active dunes (162 square kilometers) extend across 218.3 square kilometers which constitutes 46.2% of the wind-blown deposits in WDC. Since the year 1980 sand dunes have been advancing at maximum rates from 1.6 to 6.9 meters per year on an azimuth of 35-130 degrees. Rose diagrams and historical wind records verify the sand dunes reach peak advancement rates during the warm season months of April to the middle of July. During this time of year the strongest winds prevail from west-southwest when the daily maximum wind speed is near 7 meters per second. Measurements of sand dune advancement rates from the years 1980-2012 show eolian activity has spatiotemporally fluctuated within the complex. </p><p> WDC sand was observed to have distinguishing textural attributes. Sediments from active dunes were mesokurtic, symmetrical, and trended towards moderately well sorted medium sand. Sediments from stable dunes were mesokurtic and trended towards moderately sorted fine sand but varied in skew from symmetrical to fine. Micro-stereoscopic inspection of bulk samples, thin sections, and the QFL ternary diagram revealed that sand traveling down the sediment transport corridor will physically weather from a White to Grey &amp; Very Pale Brown Litharenite into a Very Dark Grey to Light Yellowish Brown &amp; Pale Brown Feldspathic litharenite sand. The QAP ternary analysis and X-ray Diffractometry demonstrated that during the processes of dune stabilization and mineralogical maturation of sand the relative weight percent of total Quartz will increase (20 to 68%) and the percent relative abundance of lithic material will decrease (100 to 45%). Feldspar minerals were plentiful and ranged from 32 to 80 relative weight percent. The mineralogical maturity of sand when interpreted by the ratio of Quartz to Feldspar grades the maturation as low to fractionally intermediate. The QAP ternary diagram demonstrates there are distinct mineralogical differences within the sand and that mixing of sediments from various supply sources have contributed to its composition. Similar to findings from the Mojave Desert (Zimbelman &amp; Williams 2002) the abundance of Feldspar and lack of Quartz enrichment in WDC dune sand may imply the mineralogical maturity is directly inherited from the parent material. The lack of Quartz enrichment also indicates WDC is geologically young and most likely has not endured extended periods of inactivity. Prominent angular to subangular grains in WDC sediments suggest dune sand has not been transported over extremely long distances. Potential sediment supply sources for dune sand may include the Jungo terrane, Comforter Basin Formation, McDermitt-Santa Rose volcanic field, and sedimentary deposits from Lake Lahontan.</p>

The structure and petrology of Upper Precambrian and Cambrian rocks have been studied in detail, in an area 38 miles north - east of Adelaide, South Australia. The rocks occur within a broad zone of high grade metamorphism on the eastern side of the Mt. Lofty Ranges. The Upper Precambrian succession consists predominantly of pelitic and semi - pelitic schists, quartzites, calc - silicate rocks and calc - schists, and the Cambrian sequence of quartzo - feldspathic schists, migmatites, granite gneiss, calc - silicate rocks and minor pelitic schists and quartzites. The rocks have reached the sillimanite grade of metamorphism and the metamorphism is of the low pressure - intermediate type. Dolerites, pegmatites, minor granodiorites and granites intrude the meta - sediments. Mineralogical and structural relationships of the granite gneiss, indicate that it has been formed by recrystalliaation of the quartzo - feldspathic schists. Small scale metamorphic differentiation, appears to have accompanied the recrystallization. The migmatites are believed to have been formed by metamorphic differentiation rather than by anatexis. Three phases of deformation are recognised in the Upper Precambrian rocks and two in the Cambrian. The second deformation recorded in the Upper Precambrian rocks does not appear in the Cambrian rocks. Each deformation has been accompanied by the formation of foliation. In the Proterozoic rocks deformed by the second and third phases of folding, the foliation is a crenulation cleavage. The deformations in both the Upper Proterozoic and Cambrian sequences are considered to be related. Petrofabric studies of quartz, scapolite and biotite are related to the respective macroscopic structures. An analysis of the chronology of crystallisation and deformation of these rocks indicates that crystallisation continued during and after each phase of deformation. Faulting commenced either prior to or during meta - morphism. Intense metasomatic activity followed a later phase of faulting resulting in the widespread development of albitites and in some cases talc ore bodies. The albitites formed in the fault zone were subsequently brecciated by further movement and later healed by the introduction of more metasoinatic fluid. / Thesis (Ph.D.) -- University of Adelaide, Department of Geology, 1966.

Thesis (Ph. D.)--University of Melbourne, 1982. / V. 1. Text and appendices--v. 2. Plates. Spine title: The Buchan Group. Includes bibliographical references (v. 1, leaves 111-115).

Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 49.

Thesis (Ph. D.)--Stanford University, 1978. / Includes bibliographical references (leaves 378-409).

Thesis. / Includes bibliographical references.

Inaug.-diss.--Karlruhe. / Lebenslauf. Includes bibliographical references.