Fault zone architecture and related permeability structures form primary controls on fluid flow in upper-crustal, brittle fault zones. We develop qualitative and quantitative schemes for evaluating fault-related permeability structures by using results of field investigations, laboratory permeability measurements, and numerical models offlow within andnearfaultzones.Thequalitativeschemecomparesthepercentageofthetotalfaultzone width composed of fault core materials (e.g., anastomosing slip surfaces, clay-rich gouge, cataclasite,andfaultbreccias)tothepercentageofsubsidiarydamagezonestructures(e.g., kinematically related fracture sets, small faults, and veins). A more quantitative scheme is developed to define a set of indices that characterize fault zone architecture and spatial variability.Thefaultcoreanddamagezonearedistinctstructuralandhydrogeologicunits that reflect the material properties and deformation conditions within a fault zone. Whether a fault zone will act as a conduit, barrier, or combined conduit-barrier system is controlled by the relative percentage of fault core and damage zone structures and the inherent variability in grain scale and fracture permeability. This paper outlines a frameworkforunderstanding,comparing,andcorrelatingthefluidflowpropertiesoffaultzones in various geologic settings.

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Fault zone architecture and permeability structure

Teleportation of a quantum state encompasses the complete transfer of information from one particle to another. The complete specification of the quantum state of a system generally requires an infinite amount of information, even for simple two-level systems (qubits). Moreover, the principles of quantum mechanics dictate that any measurement on a system immediately alters its state, while yielding at most one bit of information. The transfer of a state from one system to another (by performing measurements on the first and operations on the second) might therefore appear impossible. However, it has been shown that the entangling properties of quantum mechanics, in combination with classical communication, allow quantum-state teleportation to be performed. Teleportation using pairs of entangled photons has been demonstrated, but such techniques are probabilistic, requiring post-selection of measured photons. Here, we report deterministic quantum-state teleportation between a pair of trapped calcium ions. Following closely the original proposal, we create a highly entangled pair of ions and perform a complete Bell-state measurement involving one ion from this pair and a third source ion. State reconstruction conditioned on this measurement is then performed on the other half of the entangled pair. The measured fidelity is 75%, demonstrating unequivocally the quantum nature of the process.

Deterministic quantum teleportation with atoms

Geochronological, structural, and sedimentological data provide the basis for a regional synthesis of the evolution of the Cordilleran retroarc thrust belt and foreland basin system in the western USA In this region, the Cordilleran orogenic belt became tectonically consolidated during Late Jurassic time ( 155 Ma) with the closure of marginal oceanic basins and accretion of fringing arcs along the western edge of the North American plate Over the ensuing 100 Myr, contractile deformation propagated approximately 1000 kilometers eastward, culminating in the formation of the Laramide Rocky Mountain ranges At the peak of its development, the retroarc side of the Cordillera was divided into five tectonomorphic zones, including from west to east the Luning-Fencemaker thrust belt; the central Nevada (or Eureka) thrust belt; a high-elevation plateau (the "Nevadaplano"); the topographically rugged Sevier fold-thrust belt; and the Laramide zone of intraforeland basement uplifts and basins Mid-crustal rocks beneath the Nevadaplano experienced high-grade metamorphism and shortening during Late Jurassic and mid- to Late Cretaceous time, and the locus of major, upper crustal thrust faulting migrated sporadically eastward By Late Cretaceous time, the middle crust beneath the Nevadaplano was experiencing decompression and cooling, perhaps in response to large-magnitude ductile extension and isostatic exhumation, concurrent with ongoing thrusting in the frontal Sevier belt The tectonic history of the Sevier belt was remarkably consistent along strike of the orogenic belt, with emplacement of regional-scale Proterozoic and Paleozoic mega- thrust sheets during Early Cretaceous time and multiple, more closely spaced, Paleo- zoic and Mesozoic thrust sheets during Late Cretaceous-Paleocene time Coeval with emplacement of the frontal thrust sheets, large structural culminations in Archean- Proterozoic crystalline basement developed along the basement step formed by Neoproterozoic rifting A complex foreland basin system evolved in concert with the orogenic wedge During its early and late history ( 155 - 110 Ma and 70 - 55 Ma) the basin was dominated by nonmarine deposition, whereas marine waters inundated the basin during its midlife ( 110 - 70 Ma) Late Jurassic basin development was controlled by both flexural and dynamic subsidence From Early Cretaceous through early Late Creta- ceous time the basin was dominated by flexural subsidence From Late Cretaceous to mid-Cenozoic time the basin was increasingly partitioned by basement-involved Laramide structures Linkages between Late Jurassic and Late Cretaceous Cordilleran arc- magmatism and westward underthrusting of North American continental lithosphere beneath the arc are not plainly demonstrable from the geological record in the Cordilleran thrust belt A significant lag-time ( 20 Myr) between shortening and coeval underthrust- ing, on the one hand, and generation of arc melts, on the other, is required for any linkage to exist However, inferred Late Jurassic lithospheric delamination may have provided a necessary precondition to allow relatively rapid Early Cretaceous continen- tal underthrusting, which in turn could have catalyzed the Late Cretaceous arc flare-up

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Late Jurassic to Eocene evolution of the Cordilleran thrust belt and foreland basin system, western U.S.A.

Fluid inclusions in hydrothermal ore deposits

Implications of fault-valve behaviour for rupture nucleation and recurrence

A variety of diagenetic hematite and manganese oxide deposits occur within well-exposed Jurassic eolian and related deposits of southeastern Utah. Hematite concretions (millimeters to tens of meters in size) and strata-bound layers occur in the permeable Navajo, Page, and Entrada sandstones. Localized manganese oxide deposits without significant iron oxide occur in the overlying rocks covering the Summerville-Tidwell interval. Field, lab, and numerical modeling studies indicate the diagenetic deposits are related to the Moab fault. Fluid inclusion studies show salinities of fault fluids range from 0 to 19.7 NaCl equivalent weight percent. The d18O (SMOW) and d13C (PDB) values of cements and veins range from 7 to 27o/oo and -12 to +5o/oo, respectively. The d87Sr (SMOW) values of these cements and veins range from 0.210 to 2.977o/oo, values substantially more radiogenic than Pennsylvanian seawater. Saline brines formed from solution of Pennsylvanian salts by meteoric water and are interpreted to have flowed up the Moab fault and outward into adjacent permeable rocks. These brines are reducing from interaction with hydrocarbon, methane, organic acids, or hydrogen sulfide, and thus remove iron, manganese, and 87Sr, and bleach the sandstones near the fault. The isotopic evidence suggests multiple episodes of fluid flow up the Moab fault system. When saline, reduced brines mixed with shallow oxygenated groundwater, iron and manganese oxides were precipitated as cements to form concretions and tabular deposits in the porous sandstones. Multiple episodes of iron oxide mineralization and concretionary geometries are evident and can be explained as the result of permeability heterogeneities in the host rock, presence of favorable nucleii for precipitation, a self-organization process, or the influence of microbes.

Diagenetic Hematite and Manganese Oxides and Fault-Related Fluid Flow in Jurassic Sandstones, Southeastern Utah

Large normal fault zones are characterized by intense fracturing and hydrothermal alteration. Displacement is localized in a slip zone of cataclasite, breccia and phyllonite surrounding corrugated and striated fault surfaces. Slip zone rock grades into fractured, but less comminuted and hydrothermally altered rock in the transition zone, which in turn grades abruptly into the wall rock. Fracturing and fluid flow is episodic, because permeability generated during earthquakes is destroyed by hydrothermal processes during the time between earthquakes.

Fracturing and hydrothermal alteration in normal fault zones

Recent exploration has revealed extensive geological evidence for a water-rich past in the shallow subsurface of Mars. Images of in situ and loose accumulations of abundant, haematite-rich spherical balls from the Mars Exploration Rover ‘Opportunity’ landing site at Meridiani Planum1,2,3 bear a striking resemblance to diagenetic (post-depositional), haematite-cemented concretions found in the Jurassic Navajo Sandstone of southern Utah4,5. Here we compare the spherical concretions imaged on Mars to these terrestrial concretions, and investigate the implications for analogous groundwater-related formation mechanisms. The morphology, character and distribution of Navajo haematite concretions allow us to infer host-rock properties and fluid processes necessary for similar features to develop on Mars. We conclude that the formation of such spherical haematite concretions requires the presence of a permeable host rock, groundwater flow and a chemical reaction front.

A possible terrestrial analogue for haematite concretions on Mars

Colorful outcrop exposures of diagenetic iron oxide, clay, and carbonate cements in the Jurassic Navajo Sandstone reflect a mul- ti-phase history of fluid-rock interactions. Characteristic mineralogical and geochemical variability occurs on microscopic and outcrop scales throughout southern Utah. We identify six common diagenetic facies and evaluate formation mechanisms, paragenetic relationships, and relative timing between alteration events. The diagenetic facies have distinctive visual characteristics, variations in mineralogy, major ox- ides, trace elements, and carbon and oxygen isotopes. They include red and bleached sandstone, diffuse and concretionary iron oxide precip- itates, and carbonate concretions. Development of these facies requires changes in the interstitial fluid environment and an open geochemical system with basinwide fluid flow and variations in redox conditions. Spatial and temporal changes in paleohydrologic and diagenetic con- ditions indicate complex coupling and feedbacks between stratigraphic architecture, fluid flow, and basin evolution.

Fingerprints of Fluid Flow: Chemical Diagenetic History of the Jurassic Navajo Sandstone, Southern Utah, U.S.A.

Spectacular color variations in the Lower Jurassic Navajo Sandstone reflect stratigraphic and structural control on the spatial distribution of fluid-driven alteration. Field observations and supervised classification of Landsat 7 Enhanced Thematic Mapper (ETM+) satellite imagery show that the most extensive regional bleaching of the Navajo Sandstone occurs on eroded crests of Laramide uplifts on the Colorado Plateau in southern Utah. Alteration patterns suggest that the blind reverse faults that core the eastern monoclines associated with these uplifts were carriers for hydrocarbons and brought the buoyant fluids to the crests of monoclines and anticlines, where they bleached the sandstone in both structural and stratigraphic traps. The extent of bleaching indicates that the Navajo Sandstone (Navajo Sandstone, Aztec Sandstone, and Nugget Sandstone) may have been one of the largest hydrocarbon reservoirs known. Rapid incision and breaching of this reservoir during Tertiary uplift and erosion of the Colorado Plateau could have released enough carbon into the atmosphere to significantly contribute to global carbon fluxes and possibly influence climate.

William T. Parry

Papers

Diagenetic Hematite and Manganese Oxides and Fault-Related Fluid Flow in Jurassic Sandstones, Southeastern Utah

Fracturing and hydrothermal alteration in normal fault zones

A possible terrestrial analogue for haematite concretions on Mars

Fingerprints of Fluid Flow: Chemical Diagenetic History of the Jurassic Navajo Sandstone, Southern Utah, U.S.A.

Bleaching of Jurassic Navajo Sandstone on Colorado Plateau Laramide highs: Evidence of exhumed hydrocarbon supergiants?