The Emerald plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.
Mostly sunny
Mostly sunny; warmer
Partly cloudy
Partly cloudy
Partly cloudy
Partly cloudy
Showers likely
Emerald’s center stands about 1,150 ft above sea level. Within three miles the land runs from 1,110 ft to 1,280 ft, a difference of 170 ft: gently rolling country.
Under the town center the state geologic map shows Prairie du Chien Group (dolostone), from the Early Ordovician, 471 to 487 million years old.
The section below crosses 3 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 57×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Dolostone. Age: Early Ordovician, 471 to 487 million years old. About 14 mi of the line.
Sandstone. Age: Cambrian, 487 to 542 million years old. About 8 mi of the line.
Sandstone. Age: Ordovician, 445 to 487 million years old. About 3 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.
A raindrop that lands in Emerald reaches the Gulf of America by way of Hutton Creek, the South Fork Willow, the Willow and the Mississippi: about 1,850 river miles.
Lakes on the way: Lake Pepin and Lake Mallalieu 175.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Emerald; river miles along the main stem, rounded.
