Colloidal solutions and redispersible powders of nanocrystalline, lanthanide-doped phosphates and vanadates have been prepared in high-boiling coordinating solvents or by hydrothermal means in aqueous solution. Highly crystalline materials were obtained by both methods despite the low temperature of 2008C applied during the synthesis. The materials have been characterized by using high-resoluti...

641 Geosphere; October 2010; v. 6; no. 5; p. 641–662; doi: 10.1130/GES00532.1; 12 fi gures; 4 tables; 1 supplemental fi le. 1Supplemental File 1. Excel fi le of U-Pb (zircon) geochronologic analyses by laser-ablation multicollector ICP mass spectrometry. If you are viewing the PDF of this paper or reading it offl ine, please visit http://dx.doi.org/10.1130/GES00532.S1 or the fulltext article on...

Zircon and apatite crystals from the western Canadian shield yield (U-Th)/He dates that are the oldest yet reported for terrestrial rocks. Zircon dates from 1.73 to 1.58 Ga are consistent with independent geological and thermochronological constraints, and indicate that the rocks were at temperatures 180 C and crustal depths 7–10 km since ca. 1.7 Ga. Apatite dates from 0.95 to 0.55 Ga suggest r...

New U-Th-Pb zircon data (SIMS) from three intrusive phases of the Palaeoproterozoic Viterliden intrusion in the western Skellefte District, central Fennoscandian Shield, dates igneous emplacement in a narrow time interval at about 1.89 Ga. A locally occurring quartz-plagioclase porphyritic tonalite, here dated at 1889± 3 Ma, is considered the youngest of the intrusive units, based on the new ag...

The European Alps are a mountain belt that is characterized by a series of discrete orogenic events, which have long been recognized. Despite the inherent episodic nature of orogenic evolution, the Alps have been continuously exhumed, mainly by erosion, but also by normal faulting. Since continental collision started in the late Eocene/Early Oligocene evidence for ongoing erosional exhumation h...

The Cenozoic basins and ranges form the high topography of the northeastern Tibet that resulted from the India-Eurasia collision. Sedimentary rocks in the basins provide direct insight into the exhumation history of the ranges and the tectonic processes that led to the northeastward growth of the Tibetan Plateau. In this study, we analyzed and compared detrital zircon U-Pb ages from sands of mo...

Mantle-derived garnet peridotites are a minor component in many very high-pressure metamorphic terranes that formed during continental subduction and collision. Some of these mantle rocks contain trace amounts of zircon and micrometer-sized inclusions. The constituent minerals exhibit pre- and postsubduction microstructures, including polymorphic transformation and mineral exsolution. Experimen...

The Stirling Range Formation in southwestern Australia contains discoidal fossils previously linked to the late Neoproterozoic Ediacaran biota and possible trace fossils interpreted to have been made by vermiform, mucus-producing, motile organisms. The age of the sedimentary succession was recently reported to be between 2.0 and 1.2 billion years old, based on U–Pb geochronology of detrital zir...

Following the futile efforts of generations to reach the high standard of excellence achieved by the luthiers in Cremona, Italy, by variations of design and plate tuning, current interest is being focused on differences in material properties. The long-standing question whether the wood of Stradivari and Guarneri were treated with wood preservative materials could be answered only by the examin...