Postglacial geomorphic development of the Dinosaur Provincial Park badlands, Alberta

1987 ◽  
Vol 24 (1) ◽  
pp. 135-146 ◽  
Author(s):  
Rorke B. Bryan ◽  
Ian A. Campbell ◽  
Aaron Yair

Experimental studies concerning current geomorphic processes and erosion rates in the badlands of Dinosaur Provincial Park, Alberta, have not explained the unusual extent of badland development or prominent nonstructural near-horizontal surfaces that occur in the park. Two of these surfaces result from spillway development associated with Wisconsin deglaciation, and the extent of badland development is associated with major spillway concentration and exposure of highly erodible Cretaceous strata. A third surface is associated with erosion caused by locally generated runoff. All surfaces are blanketed with aeolian sands and silts deposited around 5500 BP, which profoundly affected the hydrology of the area and water and sediment discharge from the badlands to the Red Deer River. Subsequent stripping of the aeolian cover by streams, along with piping and tunnel erosion, has reexposed vulnerable Cretaceous strata and restored the high erosion rates now observed in these badlands.

2010 ◽  
Vol 7 (2) ◽  
pp. 1973-2015
Author(s):  
E. S. Riddell ◽  
S. A. Lorentz ◽  
D. C. Kotze

Abstract. Wetlands are undergoing considerable degradation in South Africa. As interventions are often technical and costly, there is a requirement to develop conceptual process models for these wetland systems so that rehabilitation attempts will be successful. This paper presents an approach using the geophysical methods of Electrical Resistivity Imaging (ERI) and Induced Polarization (IP) to delineate sub-surface hydro-geomorphic controls that maintain equilibrium disconnectivity of wetland-catchment processes, which through gully erosion are increasing the catchments connectivity through loss of water and sediment. The findings presented here give insight into the geomorphic processes that maintain the wetland in an un-degraded state, this allows for the development of a conceptual model outlining the wetland forming processes. The analysis suggests that sub-surface clay-plugs, within an otherwise sandy substrate are created by illuviation of clays from the surrounding hillslopes particularly at zones of valley confinement.


1978 ◽  
Vol 100 (3) ◽  
pp. 531-536 ◽  
Author(s):  
A. Gany ◽  
L. H. Caveny ◽  
M. Summerfield

Analytical studies were conducted to investigate the mechanisms of metal erosion produced by short exposures (< 2 ms) to flowing high pressure (∼ 350 MPa), high temperature (∼ 3000 K) reactive gases. Previous experimental studies established that the intense heating during the short exposure produced melting and, when reactive gases were used, oxidation of the surface and enhanced erosion. The reactions were modeled as diffusion-limited, heterogeneous surface reactions which achieved equilibrium at the gas/metal interface. Calculated results for the sequential events of initial heating, surface reactions, and melting explained and correlated the experimental trends for Fe, Al, Ti, and Mo. Rapidly increasing erosion rates with increasing O2 concentration are the result of the surface reactions between the metal and O2. As O2 concentration increases, the heating produced by the surface reaction exceeds the forced convective heating which, in turn, greatly enhances the melting rate.


2013 ◽  
Vol 32 (2) ◽  
pp. 204-234 ◽  
Author(s):  
Paul Brinkman

A Field Museum expedition to collect Late Cretaceous dinosaurs operated for three and a half months in the summer of 1922 in the Red Deer River badlands (Oldman and Dinosaur Park formations, Belly River Group) in an area now known as Dinosaur Provincial Park in southern Alberta, Canada. Associate Curator of Vertebrate Paleontology Elmer S. Riggs led the expedition. He was ably assisted by veteran collectors George F. Sternberg and John B. Abbott. A trio of novice collectors, Anthony Dombrosky, George Bedford and C. Harold Riggs, Elmer's youngest son, rounded out the party. The expedition was a success, netting several quality specimens of duckbilled dinosaurs; one small, partial theropod skeleton; an unidentified duckbilled dinosaur skull; four turtles; other miscellaneous fossil vertebrate remains; numerous fossil plants and invertebrates; and a large fossil log. In 1956, one of these specimens—a nearly complete lambeosaurine hadrosaur reconstructed as Lambeosaurus—debuted as the less fortunate partner of Gorgosaurus in the museum's iconic ‘Dinosaurs, Predator and Prey’ exhibit in Stanley Field Hall. Both of these specimens are still on display in a permanent exhibit called ‘Evolving Planet’. Another notable specimen prepared in 1999-2000 after nearly eighty years in an unopened field jacket has been identified as a juvenile Gorgosaurus. This specimen—nicknamed ‘Elmer’—was recently touring the globe as part of the ‘Dinosaurs: Ancient Fossils, New Discoveries’ exhibit. More importantly, the expedition was an invaluable shakedown experience for the fossil hunting crew and their new equipment in the months before they left on an ambitious, multi-year fossil mammal collecting expedition to Argentina and Bolivia. An oft-repeated myth holds that Riggs viewed the Alberta expedition as a failure and departed the field the moment he obtained permission to go to South America. This paper shows that myth to be unfounded.


Eos ◽  
1998 ◽  
Vol 79 (48) ◽  
pp. 589-592 ◽  
Author(s):  
Z. S. Yang ◽  
J. D. Milliman ◽  
J. Galler ◽  
J. P. Liu ◽  
X. G. Sun

2012 ◽  
Vol 518-523 ◽  
pp. 4504-4509
Author(s):  
Lu Zhang ◽  
Yuee Chen ◽  
Qing Wu

It was important to explore the law of water and sediment reduction of loess slope in different grass coverage for carrying out the grass construction and controlling slope erosion in the Loess Plateau. Using the tests of outside artificially runoff erosion simulation, in the condition of 5L/min of the scouring flows, we conducted a pilot study of sediment yield, erosion rates, and runoff sediment concentration in three different slope conditions of 15°, 20°, 25° and three grass coverage conditions of bare slope, 30%~40% and 70%~80%. The results showed that: the grass coverage has significantly influences on sediment yield, erosion rate and runoff sediment concentration of loess slope. Sediment yield of loess slope with grass coverage of 70 ~ 80% is less than 10% of that of bare slope. Under the same conditions of gradient and grass coverage, the sediment yield and runoff sediment concentration had a direct proportion with the scouring flow. Under the same conditions of gradient and scouring flows, the erosion rate and runoff sediment yield of loess slope are basically the same. Grass has a significant role in enhancing resistance to corrosion of soil and reducing erosion of loess slope.


2013 ◽  
Vol 1 (1) ◽  
pp. 311-335 ◽  
Author(s):  
C. H. Mohr ◽  
A. Zimmermann ◽  
O. Korup ◽  
A. Iroumé ◽  
T. Francke ◽  
...  

Abstract. Deforestation is a prominent anthropogenic cause of erosive overland flow and slope instability, boosting rates of soil erosion and concomitant sediment flux. Conventional methods of gauging or estimating post-logging sediment flux focus on annual timescales, but potentially overlook important geomorphic responses on shorter time scales immediately following timber harvest. Sediments fluxes are commonly estimated from linear regression of intermittent measurements of water and sediment discharge using sediment rating curves (SRCs). However, these often unsatisfactorily reproduce non-linear effects such as discharge-load hystereses. We resolve such important dynamics from non-parametric Quantile Regression Forests (QRF) of high-frequency (3 min) measurements of stream discharge and sediment concentrations in similar-sized (~ 0.1 km2) forested Chilean catchments that were logged during either the rainy or the dry season. The method of QRF builds on the Random Forest (RF) algorithm, and combines quantile regression with repeated random sub-sampling of both cases and predictors. The algorithm belongs to the family of decision-tree classifiers, which allow quantifying relevant predictors in high-dimensional parameter space. We find that, where no logging occurred, ~ 80% of the total sediment load was transported during rare but high magnitude runoff events during only 5% of the monitoring period. The variability of sediment flux of these rare events spans four orders of magnitude. In particular dry-season logging dampened the role of these rare, extreme sediment-transport events by increasing load efficiency during more moderate events. We show that QRFs outperforms traditional SRCs in terms of accurately simulating short-term dynamics of sediment flux, and conclude that QRF may reliably support forest management recommendations by providing robust simulations of post-logging response of water and sediment discharge at high temporal resolution.


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