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Research — Geochemistry

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There are 10 projects that match your criteria:
Tephra layers in Rio Grande Rift Sediments
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The Jemez Mountains volcanic field, in northwestern New Mexico, has been active for at least the past 16.5 million years, and has produced a large number of explosive and effusive volcanic eruptions during that time. Volcanic ash from the Jemez Mountains volcanic field provides a temporal record of the young eruptions from the caldera and many such deposits have been recognized in a number locations in New Mexico. The ash is present as thick deposits near the eruptive source, and as thinner deposits interbedded in ancestral Rio Grande river sediments at greater distances from the vent.

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Long Term Groundwater Monitoring in the Animas Valley
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Our agency has been collaborating with the New Mexico Environment Department (NMED) on a hydrogeology study along the Animas River in New Mexico in response to the Gold King Mine spill, which occurred in August 2015. The water released from the spill was loaded with dissolved metals and contaminated sediments, which posed a possible risk to groundwater quality in the Animas Valley.

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Hydrogeologic Investigation at White Sands National Monument
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This study focused on the shallow aquifer that occurs in the dune field with depth-to-water ranging from 1 to 3 feet below interdunal surfaces. We used hydrologic and geochemical data to identify water sources that contribute to the shallow groundwater system in the dune field and to assess how this system responds to water level fluctuations in the adjacent regional basin-fill aquifer. Hydrologic modeling was used to assess the effects of projected additional groundwater pumping in Alamogordo on the shallow dune aquifer on the Monument.

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Uplift of the Tibetan Plateau: Insights from cosmogenic exposure ages of young lava flows
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The Tibetan plateau is a product of the most dramatic tectonic event of recent geological history: the collision of the Indian sub-continent with Eurasia. In spite of the topographic and tectonic implications of the plateau, the mechanisms for its uplift remain controversial. The controversy is in large part a result of poorly constrained uplift history. Types of evidence that have been adduced for the uplift history include paleoecological date, cooling histories of plutonic and igneous rocks, and geomorphic interpretations. Some lines of evidence indicate relatively gradual uplift since the mid-Tertiary, while others support rapid acceleration of uplift during the latest Cenozoic, with the greatest portion during the Quaternary.

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Volcanic record in Antarctic ice
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Volcanic ash and associated aerosol layers in glacier ice offer a uniquely complete record of explosive volcanism. Investigation of these layers, both in bare ice areas of and in ice cores offers insight into eruptive processes, local and regional ice flow processes, and the impact of eruptions on global systems (climate and ozone depletion). The Antarctic ice sheet is an ideal place to preserve a record of volcanic eruptions. The combination of chemical fingerprinting of glass shards, and chemical analysis of volcanic aerosols associated with tephra layers in Antarctic blue ice allows establishment of a high-resolution chronology of local and distant volcanism that can help understand patterns of significant explosive volcanism, atmospheric loading, and climatic effects associated with volcanic eruptions.

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Hydrogeology of Central Jornada Del Muerto: Implications for Travel along El Camino Real De Tierra Adentro, Sierra and Doña Ana Counties, New Mexico
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Between 1598 and the 1880s, El Camino Real de Tierra Adentro (El Camino Real) served as a 1,600 mile long trade route between Mexico City and San Juan Pueblo/Ohkay Owingeh, New Mexico (north of Santa Fe). El Camino Real transects the Jornada del Muerto, located in southern New Mexico (see below figure). This stretch of the trail is thought to have been one of the most feared sections along El Camino Real due, primarily, to the scarcity of water.

The study area is located primarily in the central portion of the Jornada del Muerto Basin, extending from just North of Engle to just south of Point of Rocks and spanning the entire basin from the Caballo Mountains in the west to the San Andres Mountains to the east.

We characterized the local geology and hydrogeology of the central Jornada del Muerto with a purpose of identifying features that likely influenced the location of El Camino Real de Tierro Adentro. This study aimed to assess the relationship between the location of the trail and parajes (campsites) and water sources that would be available to travelers on the trail. The study was funded by the New Mexico Spaceport Authority (NMSA) and is the fulfillment of one of the measures specified in a mitigation plan that identifies a series of measures specifically intended to mitigate adverse effects to El Camino Real.

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Alteration and Epithermal Mineralization in the Steeple Rock District, Grant County, New Mexico and Greelee County, Arizona
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The Steeple Rock district in the Summit Mountains in southwestern New Mexico and southeastern Arizona offers an excellent opportunity to examine the relationship between the distribution and timing of the alteration and the formation of fissure veins in an epithermal environment. Five distinct types of epithermal veins occur in the district: base metals with gold-silver, gold-silver, copper-silver, fluorite, and manganese. These epithermal veins are structurally controlled, are hosted by Oligocene to Miocene volcanic and intrusive rocks, and are spatially associated with two types of alteration: neutral pH (alkali chloride or propylitic to argillic to sericitic) and acid sulfate (advanced argillic). Neutral pH alteration is the most pervasive type of alteration in the district and occurred in three stages: regional pre-mineralization, local syn-mineralization, and regional post-mineralization.

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New Mexico: Regional Brackish Water Assessments
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As New Mexico considers the use of desalinated brackish water (less than 10,000 mg/L total dissolved solid) to diversify the public water supply, many questions must first be answered. Where are the brackish water resources? What data are available? What exactly is the water chemistry? How feasible is it to use brackish water for public supply?

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Scientists Use Ancient Ore Deposits to Predict Ground Water Quality and Paleoclimate
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Two Bureau of Geology scientists, in collaboration with scientists at the United State Geological Survey, have discovered similarities between ground water systems that formed ore deposits 10 million years ago and modern ground water in the Rio Grande Rift. They reported their work in an invited presentation at the 2000 Annual Meeting of the Geological Society of America.

Dr. Virgil Lueth, mineralogist/ economic geologist, and Lisa Peters, senior lab associate at the New Mexico Geochronological Research Lab, have been studying the mineral jarosite in ore deposits from Chihuahua, Mexico, to Albuquerque.

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Cosmogenic dating of young basaltic lava flows
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Cosmogenic dating techniques have been successfully applied to dating of geomorphically-young surfaces, such as glacial moraines, beach terraces, and basaltic lava flows that have intact surface features, and hence have undergone little erosion (e.g. Phillips et al., 1997a and b; Phillips et al, in review, Dunbar and Phillips, 1996; Zreda et al., 1991, 1993; Zreda, 1994; Anthony and Poths, 1992, Laughlin et al., 1994). These techniques rely on measurement of cosmogenic nuclides that begin to build up as soon as a rock is exposed to cosmic rays. Therefore, cosmogenic techniques can be applied to dating of any surface that is composed of material that was not exposed to cosmic rays prior to formation of the surface, and has been exposed more-or-less continuously since. In the case of an extrusive volcanic rock, buildup of cosmogenic nuclides begins when the rock is erupted, so measurement of the ratio of a cosmogenic isotope to a non-cosmogenic isotope can provide an estimate of eruption age (Phillips et al., 1986).

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