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1. Hydrogeochemistry of the Middle Rio Grande aquifer system — Fluid mixing and salinization of the Rio Grande due to fault inputs

   https://doi.org/10.1016/j.chemgeo.2013.05.029  

   Williams, Amy J.; Crossey, Laura J.; Karlstrom, Karl E.; Newell, Dennis; Person, Mark; Woolsey, Emily (August 2013, Chemical Geology)
2. Active crustal differentiation beneath the Rio Grande Rift

   https://doi.org/10.1038/s41561-020-0640-z  

   Cipar, Jacob H.; Garber, Joshua M.; Kylander-Clark, Andrew R.; Smye, Andrew J. (November 2020, Nature Geoscience)

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3. Seismicity recorded in hematite fault mirrors in the Rio Grande rift

   https://doi.org/10.1130/GES02426.1  

   Odlum, M.L.; Ault, A.K.; Channer, M.A.; Calzolari, G. (November 2021, Geosphere)

   Abstract Exhumed fault rocks provide a textural and chemical record of how fault zone composition and architecture control coseismic temperature rise and earthquake mechanics. We integrated field, microstructural, and hematite (U-Th)/He (He) thermochronometry analyses of exhumed minor (square-centimeter-scale surface area) hematite fault mirrors that crosscut the ca. 1400 Ma Sandia granite in two localities along the eastern flank of the central Rio Grande rift, New Mexico. We used these data to characterize fault slip textures; evaluate relationships among fault zone composition, thickness, and inferred magnitude of friction-generated heat; and document the timing of fault slip. Hematite fault mirrors are collocated with and crosscut specular hematite veins and hematite-cemented cataclasite. Observed fault mirror microstructures reflect fault reactivation and strain localization within the comparatively weaker hematite relative to the granite. The fault mirror volume of some slip surfaces exhibits polygonal, sintered hematite nanoparticles likely created during coseismic temperature rise. Individual fault mirror hematite He dates range from ca. 97 to 5 Ma, and ~80% of dates from fault mirror volume aliquots with high-temperature crystal morphologies are ca. 25–10 Ma. These aliquots have grain-size–dependent closure temperatures of ~75–108 °C. A new mean apatite He date of 13.6 ± 2.6 Ma from the Sandia granite is consistent with prior low-temperature thermochronometry data and reflects rapid, Miocene rift flank exhumation. Comparisons of thermal history models and hematite He data patterns, together with field and microstructural observations, indicate that seismicity along the fault mirrors at ~2–4 km depth was coeval with rift flank exhumation. The prevalence and distribution of high-temperature hematite grain morphologies on different slip surfaces correspond with thinner deforming zones and higher proportions of quartz and feldspar derived from the granite that impacted the bulk strength of the deforming zone. Thus, these exhumed fault mirrors illustrate how evolving fault material properties reflect but also govern coseismic temperature rise and associated dynamic weakening mechanisms on minor faults at the upper end of the seismogenic zone. 

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4. Endorheic‐Exorheic Transitions of the Rio Grande and East African Rifts

   https://doi.org/10.1029/2018GC008176  

   Berry, M.; van Wijk, J.; Cadol, D.; Emry, E.; Garcia‐Castellanos, D. (July 2019, Geochemistry, Geophysics, Geosystems)

   Abstract Tectonic extension of continental lithosphere creates accommodation space in which sediments are deposited. Climate‐driven processes provide the mechanism by which mass is detached from hillslopes and sediments are transported into this accommodation space. These two forcings, climate and tectonics, act together to create either endorheic (internally drained) or exorheic (externally drained) rift basins. Here we use a large‐scale dynamic landscape evolution‐tectonics model to understand the contribution of tectonic processes in endorheic‐exorheic transitions. In the model, extension results in opening of an asymmetric half‐graben along a listric normal fault. Rift opening occurs in the models in wet, temperate, or semiarid climates where runoff and evapotranspiration are varied. Our numerical experiments show that slow rift‐opening rates, a slowing‐down of rift opening, or increase of headwater topography (e.g., upstream epeirogenic uplift), are tectonic situations that can cause a transition from an endorheic to an exorheic drainage state in a rift basin. Our results also show that wet climate conditions lead to a permanent exorheism that persists regardless of rift‐opening rates. In semiarid climates, endorheic conditions are favored and may last for the duration of rifting except for when rift opening is very slow. These results form an interpretive framework to study endorheic and exorheic drainage systems in natural continental rifts. In the slow‐opening Rio Grande rift, the endorheic‐exorheic transition may have occurred without dramatic climate changes. Lake‐level variations in East African rift basins are predicted by our models to result from variations in climate. 

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5. Rio Grande Water Chemistry Data from Bernalillo County, New Mexico (2006-2007)

   https://doi.org/10.6073/pasta/4e916dab1acb15764a578494f106847d  

   Van Horn, David; Dahm, Clifford (January 2016, Environmental Data Initiative)