ABOUT THIS LOCATION This Earthcache is on Iowa Avenue, north of Mile 3 Road, on the east side of the road. Like the other two stages, the coordinates take you to a parking area that is off the shoulder of the road. It is important that you do not go beyond the gate or on private property land.
GEOLOGICAL INFORMATION Near the EarthCache coordinates is a Valley Caliche Products, Inc. sign. Do not go to it; use your binoculars! A 1981 map shows this area as a caliche pit and is associated with the Cuevitas, Delmita, and Randado soils series which are somewhat similar. The Cuevitas and Randado formed in loamy soils and the Delmita in loamy and sandy soils, but the three of them were partly reworked by wind. First, a quote from Wikipedia that describes caliche. "Caliche is a sedimentary rock, a hardened natural cement of calcium carbonate that binds other materials - such as gravel, sand, clay, and silt. It occurs worldwide... generally in arid or semiarid regions . . . .
CALICHE is generally light-colored, but can range from white to light pink to reddish-brown depending on the impurities present. It generally occurs on or near the surface, but can be found in deeper subsoil deposits, as well. Layers vary from a few inches to feet thick, and multiple layers can exist in a single location. Caliche generally forms when minerals leach from the upper layer of the soil (the A horizon) and accumulate in the next layer (the B horizon), at depths of approximately 3 to 10 feet under the surface. It generally consists of carbonates in semiarid regions . . . .The deposited calcium carbonate accumulates - first forming grains, then small clumps, then a discernible layer, and finally, a thicker solid bed. As the caliche layer forms the layer gradually becomes deeper . . . ."
THE CUEVITAS SERIES consists of shallow, well drained, loamy soils on uplands and are over thick beds of caliche. The A horizon is 0 to 8 inches deep and is reddish brown fine sandy loam. The dark reddish brown is moist. They are hard yet very friable/crumbly with many fine roots. There is no B horizon. Both C horizons are pinkish white or white. The upper is 8 to 12 inches deep and is strongly cemented caliche that becomes softer with depth. The lower layer is 12 to 60 inches deep and is weakly cemented caliche.
THE DELMITA SERIES consists of well drained, loamy and sandy soils on uplands and formed over thick beds of caliche. The upper A horizon is 0 to 7 inches in depth and the lower is 7 to 13 inches in depth. Both can be yellowish red or reddish brown while the A horizon can also be brown, and are of reddish brown fine sandy loam. The B horizon is 13 to 34 inches in depth and of red sandy clay loam that is hard yet friable. The C horizon, 34 to 60 inches in depth, is pinkish white or white and strongly cemented caliche that becomes less cemented with depth.
THE RANDADO SERIES consists of shallow, well drained loamy soils on uplands and is over thick beds of caliche. The color of its A and B horizons are from yellowish red to red, brown, and to dark brown while the C horizon is pinkish white or white and changes from strongly cemented at its top to weakly cemented at the bottom. The A horizon is 0 to 9 inches in depth with fine sandy loam that is hard but very friable with many fine roots. The B horizon is at 9 to 16 inches and quite similar to A. The upper C horizon is from 16 to 20 inches and is strongly cemented. The lower C horizon is from 20 to 60 inches of less strongly cemented caliche that weakens as it descends.
The view at Stage 3 reveals a very large pit that may extend well over 1/4 mile across and perhaps 60 feet deep. Wouldn't you wonder how many truckloads of material were removed?!
EARTHCACHE INFORMATION Bring your camera and binoculars.
To receive credit for this EarthCache please do the following:
1. Describe the large rock at the Earthcache listed Coordinates and state the series and horizon you think it may belong to.
2. At stage 2 describe two different appearing rocks and state the series and horizon you think each may belong to.
3. At stage 3 (optional) take a photo with your GPS of you/group if possible, with a view of the pit and post it with your log. Note: as of 1/1/11 photos are optional, but certainly appreciated. Using your binoculars notice the water in the pit. Explain how you think the water got there?
4. The three soil series above are rather similar. State two similarities of the caliche in the C horizons of the three soil series. E-mail your answers to the EarthCache owner. You do NOT need to wait for confirmation from me before logging your find. Please do not make any reference to these answers in your log.