Related Experiment Video
Updated: Aug 7, 2026
09:49
Visualizing Hyporheic Flow Through Bedforms Using Dye Experiments and Simulation
Published on: November 18, 2015
Heterogeneities in glaciofluvial deposits using an example from new hampshire
Gordon M Sturgeon1, J Matthew Davis, Ernst Linder
1Tetra Tech NUS Inc, Wilmington, MA 01887, USA. sturgeong@ttnus.com
Ground Water
|July 22, 2006
Summary
Subsurface heterogeneity impacts contaminant migration. Geologic factors like lithofacies and sediment color significantly influence variations in permeability and metal content in glaciofluvial deposits, aiding site characterization.
Area of Science:
- Geosciences
- Environmental Science
- Hydrogeology
Background:
- Subsurface heterogeneity significantly impacts contaminant transport and in situ remediation.
- Understanding the origins of heterogeneity is crucial for developing efficient site characterization methods.
Purpose of the Study:
- To investigate the physical and chemical heterogeneity in a glaciofluvial deposit.
- To identify processes controlling spatial variations in sediment properties.
- To evaluate the utility of geologic information for characterizing observed variations.
Main Methods:
- Conducted an outcrop study in a glaciofluvial deposit in Deerfield, New Hampshire.
- Analyzed physical properties (e.g., permeability) and chemical properties (e.g., dithionite citrate-extractable metals).
- Utilized lithologic facies and sediment color as explanatory variables.
Main Results:
- Physical and chemical properties exhibited distinct spatial correlation structures.
- Lithologic facies explained 31-60% of the variation in permeability, manganese, and aluminum.
- Sediment color was a significant factor, explaining variation in iron (49%), aluminum (34%), and manganese (60%).
- (Hydr)oxide grain coatings originated from mineral weathering and redox-driven redistribution.
Conclusions:
- Lithofacies and sediment color are strong predictors of key subsurface properties.
- This information facilitates detailed mapping of permeability and metal content.
- Geologic information, specifically lithofacies and color, can aid in characterizing and modeling heterogeneity at similar glaciofluvial sites.
Related Concept Videos
01:29Gradually Varying Flow
Gradually varying flow (GVF) in open channels describes situations where water depth changes slowly along the channel due to factors like non-uniform bed slope, channel shape variations, or obstructions. This flow type occurs when the depth adjusts gradually to balance gravitational forces, shear forces, and energy requirements, resulting in a low rate of depth change.Characteristics of Gradually Varying FlowGVF is commonly observed in natural streams, rivers, and canals, where flow depth...
01:24Rapidly Varying Flow
Rapidly varying flow (RVF) in open channels is characterized by abrupt changes in flow depth over a short distance, with the rate of depth change relative to distance often approaching unity. These flows are inherently complex due to their transient and multi-dimensional nature, making exact analysis difficult. However, approximate solutions using simplified models provide valuable insights into their behavior.Key Features of Rapidly Varying FlowRVF is commonly observed in scenarios involving...
01:30Typical Model Studies
Fluid mechanics model studies often utilize scaled-down systems to predict fluid behavior in full-scale environments, such as river flows, dam spillways, and structures interacting with open surfaces. Maintaining Froude number similarity in river models is crucial, as it replicates surface flow features like wave patterns and velocities.
01:26Unsoundness of Aggregate due to Volume Change
Unsoundness in aggregates due to volume changes is primarily caused by the physical alterations aggregates undergo, such as freezing and thawing, thermal changes, and wetting and drying. Unsound aggregates, when subjected to these changes, result in volume change upon disintegration. This, in turn, contributes to the deterioration of concrete, including scaling, pop-outs, and cracking. Particular types of aggregates, such as porous flints, cherts, and those containing clay minerals, are...
01:24Design Example: Aggregate Gradation
The right type and quality of aggregates are crucial for concrete as they significantly influence its properties, mix proportions, and cost-effectiveness. If different sources are available for sand, the commonly used fine aggregate in concrete, the selection of sand is primarily based on its gradation.
The grading, or particle-size distribution, of sand is determined using sieve analysis, with standard sizes ranging from 150 μm to 10 mm (ASTM No. 100 sieve to 3⁄8 in. sieve). Sand is sampled...
The grading, or particle-size distribution, of sand is determined using sieve analysis, with standard sizes ranging from 150 μm to 10 mm (ASTM No. 100 sieve to 3⁄8 in. sieve). Sand is sampled...