The Rio Grande rift of central New Mexico is dominated by NNW- to NE-striking normal faults of Late Oligocene to Quaternary age. Crustal extension is distributed across many subparallel fault blocks. Fault traces commonly show abrupt changes in strike, often bifurcate, and occasionally step over to adjacent faults along transverse ramps (e.g. Chamberlin et.al, 1994a; Chamberlin and Harrison, 1996). Based on observations of striated fault surfaces most rift faults are apparently dip-slip to slightly oblique-slip normal faults. There is generally little or no evidence of significant strike slip faulting in areas of high-angle normal faulting. However, minor lateral slip may occur where a north or south propagating fault tip is deflected by a preexisting basement shear zone oriented at a high angle to the propagating rift fault (Chamberlin, 2000). Broad zones of lateral shear may be accommodated by a combination of minor vertical axis rotations and distributed oblique-slip normal faulting in which the dip-slip component is dominant.
The Point Lookout Sandstone on the Jicarilla Apache Reservation in Rio Arriba County contains geological layers called “beach placer deposits”. Beach-placer sandstone deposits are accumulations of dense minerals that form on beaches, or in shallow ocean water. They form by mechanical settling of heavy minerals by the action of waves, currents, and winds. These deposits contain Rare Earth Elements (REE) which are important commodities required to manufacture green technologies, like wind turbines and hybrid/electric cars and are essential in most of our electronic devices, like cell phones and laptop computers.
Microbes can play an important role in geology and in the precipitation and dissolution of mineral components. Uranium is most commonly mobile in the environment with a charge of 6+, referred to as oxidized uranium, usually forming the uranyl molecule, UO22+. It is most commonly precipitated with the oxidation state of 4+, referred to as reduced uranium, to form minerals as the molecule U3O8. Microbes, which are constantly seeking metals and molecules that they can use as nutrients, energy sources, and electron acceptors, often reduce such metal species (changing uranium 6+ as UO22+ to uranium 4+ as U3O8, for example) as part of their metabolic processes; however, not all microbes reduce all metal species. Identifying microbes that can reduce the uranyl molecule and therefore create an environment ripe for uranium precipitation could be important for understanding how uranium deposits occur and for identifying possible tools for uranium mine remediation.
PhD. Student, Drew Levy, from the University of Nevada-Reno received an award for his proposal and will be working with Dr. Matthew Heizler.
The New Mexico Geochronology Research Laboratory (NMGRL) is a participant in the “Awards for Geochronology Student Research” program (AGeS2 ). AGeS2 grants are funded by the National Science Foundation Earthscope program, in conjunction with the Geological Society of America, and are designed to link students with geochronology laboratories to facilitate in depth student understanding of geochronology methods with hands on experience ultimately leading to publication of new data.
The MINES Thermodynamic Database is an initiative to generate a revised internally consistent thermodynamic dataset for minerals, aqueous species and gases for simulating geochemical processes at hydrothermal conditions in the upper crust (≤5 kbar and ≤600 °C) with focus on ore forming processes.
