The Greenfield 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.
92° on Nov. 16, 2008, the hottest reading for this week of the year since 1902. Next is 91° in 1933.
Greenfield’s center stands about 280 ft above sea level. Within three miles the land runs from 200 ft to 400 ft, a difference of 200 ft: gently rolling country. The highest named summit within 15 miles is Pinyon Peak, about 5,210 ft, 13 miles southwest.
Under the town center the state geologic map shows Quaternary alluvium and marine deposits (coarse-detrital), from the Pleistocene to Holocene, less than 2.6 million years old.
The section below crosses 11 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 6×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Rhyolite. Age: Late Oligocene to Early Miocene, 22 to 24 million years old. About 4 mi of the line.
Coarse-detrital. Age: Pleistocene to Holocene, less than 2.6 million years old. About 4 mi of the line.
Sandstone, mudstone. Age: Oligocene to Pliocene, 2.6 to 34 million years old. About 4 mi of the line.
Sandstone, conglomerate. Age: Miocene to Pleistocene, less than 23 million years old. About 4 mi of the line.
Mica-schist. Age: Late Cretaceous to Eocene, 34 to 100 million years old. About 3 mi of the line.
Coarse-detrital. Age: Pleistocene, less than 2.6 million years old. About 1 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale. 5 smaller units along the line are not listed.
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 Greenfield reaches the Pacific Ocean by way of the Salinas: about 55 river miles.
Often dry. About 90% of the way is mapped as streams that run only after rain or snowmelt; the water makes the whole trip in floods.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Greenfield; river miles along the main stem, rounded.
Greenfield has a cold semi-arid climate. Summer afternoons average 85° in July; winter nights fall to about 37° in December. About 12 inches of rain fall in a normal year.
On November 14 Greenfield normally reaches 70° and falls to 41°. The record high is 91°, in 1933; the record low 24°, in 1955. The most rain on this date, 1.50 in, fell in 1972.
Normals 1991–2020 and records since 1902 at King City, 10 miles southeast. NOAA, through RCC-ACIS.