Mineral Physics Commons^™

Trace Element And Stable Isotope Data From A Flowstone In A Natural Cave Of The Mining District Of Sw Sardinia (Italy): Evidence For Zn²⁺-Induced Aragonite Precipitation In Comparatively Wet Climatic Conditions, Guglielmo Angelo Caddeo, Jo De Waele, Franco Frau, Loren Bruce Railsback

International Journal of Speleology

A speleothem from Crovassa Azzurra, a mine cave in SW Sardinia (Italy), has been analysed for mineralogy, minor and trace elements and stable isotopes. It is composed of layers of primary calcite and aragonite, with a region of secondary calcite. The primary carbonate is strikingly rich in Zn and Pb, presumably as the result of transport in solution from overlying Pb-Zn deposits. Immediately below the transition between calcite and aragonite, concentrations of Zn, Cd and P increase. At the transition between aragonite and Pb-rich aragonite, concentrations of Pb and P increase. Stable isotopes indicate an evolution toward more humid periods …

Secondary Halite Deposits In The Iranian Salt Karst: General Description And Origin, Michal Filippi, Jiří Bruthans, Lukáš Palatinus, Mohammad Zare, Naser Asadi

International Journal of Speleology

This paper summaries 12 years of documentation of secondary halite deposits in the Iranian salt karst.

A variety of secondary halite deposits was distinguished and classified into several groups, on the basis of the site and mechanism of their origin. Deposits formed: i) via crystallization in/on streams and pools, ii) from dripping, splashing and aerosol water, iii) from evaporation of seepage and capillary water, and iv) other types of deposits. The following examples of halite forms were distinguished in each of the above mentioned group: i) euhedral crystals, floating rafts (raft cones), thin brine surface crusts and films; ii) straw …

2,2′,5,5′-Tetra­Chloro­Benzidine, Onome Ugono, Marcel Douglas, Nigam Rath, Alicia Beatty

Chemistry & Biochemistry Faculty Works

In the crystal structure of the title compound, C12H8Cl4N2, mol­ecules lie on crystallographic twofold axes at the centre of the C-C bonds linking the benzene rings, such that the asymmetric unit consists of a half-mol­ecule. The individual mol­ecules participate in inter­molecular N-H...N, N-H...Cl, C-H...Cl and Cl...Cl [3.4503 (3) Å] inter­actions.

High Pressure Structural Studies On Eus Nano Particles Up To 52 Gpa, Kristie Canaday, Ravhi S. Kumar

Undergraduate Research Opportunities Program (UROP)

Crystal size reduction in bulk materials changes the structural and magnetic properties considerably [1]. More importantly the transition pressure is strongly influenced by temperature, pressure, and the crystallite size effect. Rare earth europium chalcogenides crystallize in the NaCl (rock salt) type structure. The interest in Eu nanomaterials is motivated by the possibility of their use in magnetic devices [2,3]. Recent studies suggest that europium chalcogenide nanocrystals exhibit significant changes in their structural and magnetic properties, compared to bulk chalcogenides, when the nanocrystal diameter decreases. The crystal structure and phase transition behavior of EuS nanoparticles have been investigated and compared as …

Determination Of Olivine Orientation Dependence Through Raman Spectroscopy, Alexandra J. Leandre, Joseph Lussier, Brittany Morgan, Michael Rodriguez

Undergraduate Research Opportunities Program (UROP)

Raman spectra were taken of olivine for analysis of vibrational energy intensity ratios. This allowed for determination of its crystal orientation. Garnet inclusions in peridotite were mapped and Raman spectra were taken for these as well. The inclusions could not identified, and data from the Raman spectra proved inconclusive due to difficulty in removing background signal.

Detrital Zircon Geochronology For Neoproterozoic To Cambrian Sediment Sources Of The Deep Creek Range And The Pilot Range In The Southwestern United States, Kaysea Perry

Earth and Soil Sciences

Detrital zircon studies of miogeoclinal sediments can help provide a deeper look into the mechanisms leading to continental breakup by studying the evolution of the continental margin of North America. Few detrital zircon studies have been conducted to support previous research and theories about the sedimentation of the Miogeocline from the Neoproterozoic to the Cambrian. Studies targeted at the Basin and Range province of the western United States show a trend of increasing local sediment sources. We analyzed detrital zircons from the Pilot and Deep Creek Ranges in Nevada and Utah via LA-MC-ICP-MS at the University of Arizona LaserChron Center …

Fluid Budget Of Metasedimentary Rocks From A Tertiary Accretionary Prism And Connections To Seismicity, Olympic Peninsula, Northwest Washington State, Holly Makena Macfadden Rotman

All Master's Theses

Metamorphic dehydration reactions and fluid movement in accretionary prisms have been linked to the recently discovered episodic tremor and slip (ETS) earthquake events along subduction zones, but prior studies lack the detail to effectively test the hypothesis that fluid flow triggers ETS events. I conducted field work along a 52.5 km transect on the Olympic Peninsula metasedimentary accretionary prism of the Cascadia subduction zone, and collected approximately 40 representative samples of sandstone and mudrock that were buried to 6–15 km. This depth range intersects the 10–50 km depth range of ETS events. My objectives are to quantify the water flow …