We use a variety of 1D, 2D, and 3D numerical models to assist in the interpretation of erosion and sedimentation rate data collected in our laboratories. Many of the models we use are developed "in house" while others are developed as part of collaborative efforts with scientists around the world.
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Coupled thermo-kinematic models
The figure shows a result from a 3-D thermo-kinematic model. The top surface in the figure is the topography of the Waddington region of the Coast Mountains, British Columbia. The lower two surfaces are the apatite (U-Th)/He and fission track closure isosurfaces beneath the topography. Models like this one are frequently used in our group to aid in the quantitative interpretation of low-temperature thermochronometer data. Important information that can be gained by integrating these models with data include evaluation of the magnitude and rates of erosion and the kinematic and structural evolution of active mountain ranges. The field work and sample collection/analysis are integral parts of our modeling efforts.
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Coupled surface process, atmospheric, and kinematic models
The below figure shows a result from a coupled atmospheric, surface process, and kinematic model. The model predicts erosion rates and topographic evolution for a 150 km wide, and 400 km long mountain range that has a uniform vertical uplift rate. This model is unique in that the precipitation rate across the range (colors draped over topography) is predicted from a physically based atmospheric model. The precipitation field is fully coupled and dependent on how the topography evolves. Models like this one are used in our group to better understand how climate, and tectonics interact and influence topographic evolution and long term erosion rates in mountains. We test our models of different field areas with a variety of different data types, including low-temperature thermochronometers, cosmogenic isotopes, and short-lived nuclides. However, we still have a lot we can learn about climate, tectonics and topography from just simple, well designed numerical modeling studies.
Paleoclimate modeling is now a regular component in our analysis of orogen evolution. We use global and regional general circulation models to quantify how climate may have varied as an orogens topography evolves. This approach is particularly useful for understanding how past precipitation and erosion rates may have differed from modern rates. It is also crucial for understanding how biologic controls on landscape evolution may have changed through time.
The below figure shows a palinspastic restoration of the northern Bolivian fold and thrust belt (Modified from McQuarrie, 2000) where we have conducted a thermochronometry and erosion study. We integrate balanced cross sections with thermochronometry and numerical modeling to better understand the kinematic and erosional history of active mountain ranges. Through this integration of techniques we hope to better understand the relative roles, and significance, of climate and tectonics on the evolution of active mountain ranges.
We acknowledge the kind donation by Petroleum Experts Ltd of 10 Educational Institution licences for the 3D-modelling software "Move". The commercial equivalent of the software donation is £1,525,561.89.