@article{HilleyBlisniukStrecker2005,
  author    = {Hilley, G. E. and Blisniuk, Peter Michael and Strecker, Manfred},
  title     = {Mechanics and erosion of basement-cored uplift provinces},
  year      = {2005},
  abstract  = {Basement-cored uplift provinces are often characterized by high-angle reverse faulting along preexisting crustal heterogeneities, which may greatly affect the mechanics of deformation and the coupling between erosion and orogenic structure. Herein we construct a coupled deformation-erosion model to understand the mechanics and erosion of mountain belts in which the spatial distribution of deformation is largely influenced by the presence of preexisting high-angle faults. In this case, deformation is accommodated along, and topography is built above, these structures. This topographic loading leads to increasing lithostatic stresses beneath these regions. As a result, active deformation may migrate to frictionally stronger structures in adjacent regions where lithostatic loading is lower. The migration of deformation to such nearby structures depends on the Hubbert-Rubey pore fluid pressure ratio of the crust (lambda), the orientations of the frictionally weaker and stronger preexisting faults (beta(1) and beta(2), respectively), the friction coefficients (mu(b1) and mu(b2)) and Hubbert-Rubey fluid-pressure ratios (lambda(b1) and lambda(b2)) of these faults, and the surface slope of the topography above the frictionally weaker structure (alpha), assuming zero surface slope above the frictionally stronger structure. In general, we found that for a given alpha and beta(1), as mu(b1) increases lambda=lambda(b1)=lambda(b2) increases, and beta(2) decreases, the value of mu(b2) required to force deformation to migrate increases. However, as erosional processes lead to decreasing surface slopes, deformation will be inhibited from migrating to frictionally stronger structures in adjacent regions. Our model results may help to explain some aspects of the deformation observed and the possible correlation between precipitation and the migration of deformation within these tectonic provinces},
  language  = {en}
}
@article{HilleyStrecker2005,
  author    = {Hilley, G. E. and Strecker, Manfred},
  title     = {Processes of oscillatory basin filling and excavation in a tectonically active orogen : Quebrada del Toro Basin, NW Argentina},
  issn      = {0016-7606},
  year      = {2005},
  abstract  = {Intramontane basins may act as important sediment storage areas, serve as recorders of the history of deformation, record syntectonic deposition, and document the evolution of climatic conditions during deposition. We document the timing, cyclicity, and processes that led to the filling and reexcavation of the intramontane Quebrada del Toro basin in NW Argentina. Geomorphic and geologic observations indicate that the basin was filled with sediment that has been subsequently excavated at least two times in the last similar to 8 m.y. The last filling and excavation cycle occurred within the last 0.98 m.y. and has led to the deposition and removal of similar to 61.4 km(3) of material from the basin, leading to a basin-wide averaged minimum denudation rate of 0.16 mm/yr. Aggradation within the basin took place due to channel steepening of the downstream fluvial system that connects the intramontane basin to the foreland. This portion of the fluvial system is actively incising through an uplifting bedrock zone. We use observations within the Toro to test a quasiphysically based model of channel aggradation behind a rising base level that rises due to downstream channel steepening. Our work shows that the bedrock incision rate constant required to reproduce conditions observed within the Toro basin is consistent with values measured independently in similar rock types. Therefore, in intramontane basins that experience similar processes of filling and evacuation, this model may be used to assess the relative importance of tectonic rock uplift, bedrock resistance to fluvial incision, and climate in determining the geomorphic and sedimentologic history of these basins},
  language  = {en}
}
@article{HilleyStreckerRamos2004,
  author    = {Hilley, G. E. and Strecker, Manfred and Ramos, V. A.},
  title     = {Growth and erosion of fold-and-thrust belts with an application to the Aconcagua fold-and-thrust belt, Argentina},
  year      = {2004},
  abstract  = {[1] The development of topography within and erosional removal of material from an orogen exerts a primary control on its structure. We develop a model that describes the temporal development of a frontally accreting, critically growing Coulomb wedge whose topography is largely limited by bedrock fluvial incision. We present general results for arbitrary initial critical wedge geometries and investigate the temporal development of a critical wedge with no initial topography. Increasing rock erodibility and/or precipitation, decreasing mass flux accreting to the wedge front, increasing wedge sole-out depth, decreasing wedge and basal decollement overpressure, and increasing basal decollement friction lead to narrow wedges. Large power law exponent values cause the wedge geometry to quickly reach a condition in which all material accreted to the front of the wedge is removed by erosion. We apply our model to the Aconcagua fold-and-thrust belt in the central Andes of Argentina where wedge development over time is well constrained. We solve for the erosional coefficient K that is required to recreate the field-constrained wedge growth history, and these values are within the range of independently determined values in analogous rock types. Using qualitative observations of rock erodibilities within the wedge, we speculate that power law exponents of 1/3 less than or equal to m less than or equal to 0.4 and 2/3 less than or equal to n less than or equal to 1 characterize the erosional growth of the Aconcagua fold-and-thrust belt. This general model may be used to understand the development of mountain belts where orogenic wedges grow as they deform at their Coulomb failure limit},
  language  = {en}
}
@article{HilleyStrecker2004,
  author    = {Hilley, G. E. and Strecker, Manfred},
  title     = {Steady state erosion of critical Coulomb wedges with applications to Taiwan and the Himalaya},
  year      = {2004},
  abstract  = {[1] Orogenic structure appears to be partially controlled by the addition to and removal of material from the mountain belt by tectonic accretion and geomorphic erosion, respectively. We developed a coupled erosion-deformation model for orogenic wedges that are in erosional steady state and deform at their Coulomb failure limit. Erosional steady state is reached when all material introduced into the wedge is removed by erosion that is limited by the rate at which rivers erode through bedrock. We found that the ultimate form of a wedge is controlled by the wedge mechanical properties, sole-out depth of the basal decollement, erosional exponents, basin geometry, and the ratio of the added material flux to the erosional constant. As this latter ratio is increased, wedge width and surface slopes increase. We applied these models to the Taiwan and Himalayan orogenic wedges and found that despite a higher flux of material entering the former, the inferred ratio was larger for the latter. Calculated values for the erodibility of each wedge showed at least an order of magnitude lower value for the Himalaya relative to Taiwan. These values are consistent with the lower precipitation regime in the Himalaya relative to Taiwan and the exposure of crystalline rocks within the Himalayan orogenic wedge. Independently determined rock erodibility estimates are consistent with the accretionary wedge sediments and metasediments and the crystalline and high-grade metamorphic rocks exposed within Taiwan and the Himalaya, respectively. Therefore differences in rock type and climate apparently lead to key differences in the erosion and hence orogenic structure of these two mountain belts},
  language  = {en}
}
@article{CarrapaAdelmannHilleyetal.2005,
  author    = {Carrapa, Barbara and Adelmann, Dirk and Hilley, G. E. and Mortimer, Estelle and Sobel, Edward and Strecker, Manfred},
  title     = {Oligocene range uplift and development of plateau morphology in the southern central Andes},
  year      = {2005},
  abstract  = {[1] The Puna-Altiplano plateau in South America is a high-elevation, low internal relief landform that is characterized by internal drainage and hyperaridity. Thermochronologic and sedimentologic observations from the Sierra de Calalaste region in the southwestern Puna plateau, Argentina, place new constraints on early plateau evolution by resolving the timing of uplift of mountain ranges that bound present-day basins and the filling pattern of these basins during late Eocene-Miocene time. Paleocurrent indicators, sedimentary provenance analyses, and apatite fission track thermochronology indicate that the original paleodrainage setting was disrupted by exhumation and uplift of the Sierra de Calalaste range between 24 and 29 Ma. This event was responsible for basin reorganization and the disruption of the regional fluvial system that has ultimately led to the formation of internal drainage conditions, which, in the Salar de Antofalla, were established not later than late Miocene. Upper Eocene-Oligocene sedimentary rocks flanking the range contain features that suggest an arid environment existed prior to and during its uplift. Provenance data indicate a common similar source located to the west for both the southern Puna and the Altiplano of Bolivia during the late Eocene- Oligocene with sporadic local sources. This suggests the existence of an extensive, longitudinally oriented foreland basin along the central Andes during this time},
  language  = {en}
}