Alluvial Sediment Thickness in the Big Thompson River Valley

S-wave refraction data collected along three roads crossing the Big Thompson River valley in Colorado were processed to model subsurface geology. The data provide estimated velocities and thicknesses for layered-earth models, resulting in three cross-sections of the valley. The work was summarized by the USGS and originates from the CEOS_EXTRA organization via NASA EarthData.

Use Cases

• Model alluvium thickness, ranging from 2 to 13 meters, across three distinct cross-sections of the valley.
• Estimate S-wave velocities for subsurface soil and alluvial layers to characterize material properties.
• Analyze the spatial variation in bedrock depth, identified as the upper transition member of the Pierre Shale.
• Compare subsurface complexity between cross-sections, particularly near the confluence of the Big Thompson and Little Thompson Rivers.
• Map the thickness of the surface soil layer, which varies from 0.2 to 1.5 meters, over the alluvium.

Strengths

• Provides three detailed geologic cross-sections of a river valley.
• Reports specific thickness ranges for soil (0.2-1.5 m) and alluvium (2-13 m) layers.
• Uses S-wave refraction, a standard geophysical method, for subsurface data collection.

Limitations

• The exact number of data points, rows, or sample locations is unknown.
• Spatial coverage is limited to three specific cross-sections along roads.
• Data collection date and temporal context are not provided.

Provenance

Source

CEOS_EXTRA organization, accessed via NASA EarthData, with a summary provided by the USGS.

Collection Method

S-wave refraction data collection and traveltime processing to estimate velocities and thicknesses for layered-earth models.

Geography

Big Thompson River valley, Colorado, USA, specifically along three roads crossing the valley.