Trace elements diffuse negligible distances through the pristine crystal lattice in minerals: this is a fundamental assumption when using them to decipher geological processes. For example, the reliable use of the mineral zircon (ZrSiO4) as a U-Th-Pb geochronometer and trace element monitor requires minimal radiogenic isotope and trace element mobility. Here, using atom probe tomography, we doc...

Titanium oxide (rutile, TiO2) and zircon (ZrSiO4), known insoluble ceramic materials, are commonly used for coatings of implant materials. We investigate the release of zirconium, titanium, aluminum, iron, and silicon from different micron-sized powders of 6 powders of natural rutile (TiO2) and zircon (ZrSiO4) from a surface perspective. The investigation includes five different synthetic body ...

New detrital-zircon geochronologic data reveal that a through-going paleoriver connected Texas with Nevada in Late Triassic time. Sandstone from the Upper Triassic Santa Rosa Sandstone (Dockum Group) from northwestern Texas contains a detrital zircon suite nearly identical to that found in western Nevada in the Upper Triassic Osobb Formation (Auld Lang Syne Group, correlative with the Chinle Fo...

Zircon appears to be a suitable medium for thermoluminescence (TL) dating of sediments from the Quaternary. TL of zircon results predominantly from internal irradiation, due to the relatively high internal concentrations of a-emitting U and Th. The internal dose predominates over the external one that is caused by the surrounding geological layers and cosmic rays. Measurement of the TL buildup ...

Few terrestrial localities preserve more than a trace lithic record prior to ca. 3.8 Ga greatly limiting our understanding of the first 700 Ma of Earth history, a period inferred to have included a spike in the bolide flux to the inner solar system at ca. 3.85-3.95 Ga (the Late Heavy Bombardment, LHB). An accessible record of this era may be found in Hadean detrital zircons from the Jack Hills,...

α-decay damage and recrystallization in natural zircon (with dose ranging from 0.06 to 23.3 × 1018 α-events g−1) were studied using polarized reflection infrared spectroscopy. The experimental results show that α-decay damage leads to a gradual decrease in reflectivity and a loss of anisotropy of IR spectra. Recrystallization of damaged zircon is found as a multi-stage process with a strong dep...

Etched tracks of apatite and zircon are both widely used for the determination of the thermal history of Earth’s crust. The present understanding of the annealing process is largely limited to mathematical fits to data for etched track-lengths as a function of temperature and time. Details of the annealing of unetched, latent tracks at the atomic scale have remained elusive, as the original tra...

A preliminary report on the toxicology of zircon (Harding, 1948) gave some details of the properties and uses of this substance and suggested that it was extremely inert within the animal body. At the time of the publication of this preliminary report an experiment was almost completed during which rats were exposed to afairly high concentration (725,000 particles per cc. of air) of zircon dust...

A process is described which involves infiltration of aluminum nitrate into partially sintered (porous) zircon bodies. Infiltration kinetics were studied using infiltration curves with two distinct regions. The final infiltrated samples were sintered at 1600 °C for 2 h and yielded specimens containing the tetragonal zirconia.The experimental results show that in spite of the similar porosity of...

The Bouse Formation in the lower Colorado River trough holds an important record of the onset of the modern drainage patterns in the southwestern United States. It comprises calcareous and clastic infi ll deposited during fl ooding of several basins, including the Bristol and Blythe subbasins of Lake Bouse. An intercalated ash bed, which is key to constraining its depositional age, is exposed i...