Mark T . Brandon

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The apatite fission-track method is used to determine the exhumation history of the Olympic subduction complex, an uplifted part of the modern Cascadia accretionary wedge. Fission-track ages are reported for 35 sandstones from the Olympic subduction complex, and 7 sandstones and 1 diabase from the Coast Range terrane, which structurally overlies the Olympic(More)
Six late Quaternary river terraces, preserved along the Clearwater River in northwestern Washington State, provide a ;140 ka record of long-term incision and uplift across the western side of the Cascadia forearc high. Terrace ages are constrained by weathering rind and radiocarbon dating and by correlation to dated coastal glacio-fluvial deposits and the(More)
The functional relationship between erosion rate and topography is central to understanding both controls on global sediment flux and the potential for feedback between tectonics, climate, and erosion in shaping topography. Analysis of a high-resolution (10-m-grid) DEM transect across the convergent orogen of the Olympic Mountains reveals a non-linear(More)
The dynamic system of tectonics and erosion contains important feedback mechanisms such that orogenic systems tend toward a steady state. This concept is often invoked, but the nature of the steady state is commonly not specified. We identify four types of steady state that characterize the orogenic system and illustrate these cases by using numerical-model(More)
The Olympic subduction complex (OSC), exposed in the Olympic Mountains of northwest Washington State, consists of an imbricated assemblage of Cenozoic sandstone, mudstone, and minor pillow basalt. The tectonic evolution of the OSC has been difficult to resolve because of poor age control, especially for the more easterly parts of the complex. The fission(More)
We present two mutuallv contradictorv hvpotheses for the midand Late &etaceous paleogeo&aphy of the w k t & margin of North America. In Hypothesis A, representative of a family of models based on geologic eGaence, the.In&lar and IntermontaGe superterranes and the intervening mid-Cretaceous Coast Mountains orogen were situated in their present positions(More)
[1] The incision of rivers in bedrock is thought to be an important factor that influences the evolution of relief in tectonically active orogens. At present, there are at least six competing models for incision of bedrock rivers, but these models have received little quantitative testing. We statistically evaluate these models using observations from the(More)