The subsurface geology of the central Florida peninsula involves complex processes and relationships between the surface environment and their effects on the subsurface geology. The west-central portion of the Florida peninsula has a hidden relationship between the land surface and the complex, underlying geology.
The geomorphology of this region is designated as karst plains, karst hills , and karst hills and valley. The state's springs occur primarily within the Ocala Karst District and the Dougherty Karst Plain District. Karst landscapes show characteristic landforms caused by chemical dissolution, such as karren (crevices , chimneys, and channels), dolines and sinkholes (closed depressions) and poljes (large depressions with flat floors). Some of these features are hidden from view by the relatively thin veneer of soil material. However, it is the karstic geology that is responsible for many of Florida’s springs and provides our “Window to the Aquifer”.
The Rainbow Springs Headsprings is the the result of where pressure forces water being stored in underground cavities in the lime rock upward to natural openings at the surface. These springs occur in areas where karst features (for example, sinkholes and caves) are common, the potentiometric surface of the Florida Aquifer System (FAS) is highenough and the surface elevations are low enough to allow groundwater to flow at the surface.
The Rainbow Springs complex is comprised of at least 4 major spring vents and many minor spring vents. These areas are where the karstic limestone bedrock has dissolved and created pathways for the aquifer waters to come to the surface.
For credit for this Earth Cache, please answer the following questions (If answers are not submitted, the log will be deleted.):
Field Work:
1) Estimate the elevation difference (in feet) between the water level in the springhead and the Visitors Center on top of the hill?
2) Name the type of stone the building center is constructed with? Where was the stone quarried?
3) The Rainbow Springs complex contains many spring vents. One of these vents can be seen near which waterfall in the park?
Optional: One of the minor vents may be observed along the walkways in the park. Please take a picture and post.
Home Work:
4) Name the classification system used for carbonate sedimentary rocks.
5) Identify the chemical reaction (formula) describing limestone dissolution to create karst features.