This is an Earthcache – as such, there is no physical cache. Instead after examining the memorial stone at the posted coordinates you will answer 3 earth science questions and message me the answers. This earthcache is located in Myakka River State Park with permission. For more information about hours of operation, entrance fees (also listed at the bottom of the cache page), and park rules please visit this Myakka River State Park LINK.
SUWANEE LIMESTONE
On July 16, 1966 this stone memorial was dedicated here at Myakka River State Park. This 34-Ton boulder was selected at the Lansing Rock Quarry in Brookeville, FL to host a memorial plaque dedicated to the four members of the Sarasota County Freshwater Fish and Game Protective Association who were instrumental in creating this park.
Brookeville in Hernando County, Florida north west of here, and mining operations there produce materials essential to roads, bridges, schools, homes and hospitals in the region and across Florida. Limestone is sedimentary rock that is typically a yellowish to cream colored stone, and full of large identifiable fossils.
Suwannee Limestone was originally deposited in a shallow, marine environment where wave action and fluctuating sea level affected the size and composition of the grains that comprise this stone. Many of these creatures used calcium ions and carbon dioxide in the ocean to manufacture shells and skeletons of Calcium Carbonate (CaCO3), just as clams, oysters, and corals still do today. Studies of the fossils contained within the Suwannee Limestone confirmed an early Oligocene age (about 28.1 million years ago), and include fossils such as Rhyncholampas gouldii, mollusks, foraminifera, and coral.
When these animals died, their shells sunk down, and settled on the sea floor. Over time, more and more layers built up, and were squished together under the wait of the seas and layers. Eventually, with enough pressure, the layers were cemented into Limestone rock through a process called lithification.
Weathering is the breakdown of rock by physical, chemical or biological processes. Limestone areas are predominantly affected by chemical weathering when rainwater, which contains a weak carbonic acid, reacts with limestone. This causes the limestone to dissolve, expose fossils, and create holes. Carbon dioxide from the respiration of animals (and people) is one cause of increased carbon dioxide in the atmosphere, as well as burning fossil fuels. Carbon dioxide in the atmosphere forms very dilute carbonic acid when it dissolves in rain. Evidence of chemical weathering can be seen in areas where limestone is exposed to the elements. Much of Suwannee Limestone has been altered by geochemical weathering processes and changed to a gray dolostone over time.
LOGGING REQUIREMENTS:
To log this Earthcache: Read the geology lesson below, observe the boulder at the posted coordinates, and answer these three questions below. Answers can be sent via e-mail or messenger contacts on my Geocaching profile within a reasonable time. Group answers are fine, but please include the members of the group you are with.
QUESTION 1. What is the size of the largest fossil you found. (Example: The shell is the size of a quarter, or the size of a pencil eraser, or the size of your drivers license... be creative in what you use.)
QUESTION 2. Observe if the stone is still yellowish or if it is grayish. From the colors you see, do you think that this rock has geochemically weathered into a dolomite?
QUESTION 3. Can you find any weathered holes large enough fit your fist in?
OPTIONAL PHOTO: Posting a photo that readily indicates that you (and anyone else logging the find) are at the location.
Awesnap has earned GSA's highest level:
REFERENCES:
1. PART I Suwanee Limestone in Hernando and Pasco Counties, Florida, J.William Yon & C.Hendry, Florida Department of Natural Recources,Bulletin 54, 1972 original-ufdc.uflib.ufl.edu
2. Featured Formation - The Suwannee Limestone, website content.govdelivery.com
3. The limestone, dolomite, and coquina resources of Florida, W.Schmidt, R.Hoenstien, & M.Knapp, Florida Department of Natural Recources,Report of Investigation 88, 1979 original-ufdc.uflib.ufl.edu
4. 34-Ton Rock Memorial Dedicated, Tampa Bay Times, July 17, 1966, Page 8, Newspaper, newspapers.com
Park Entrance Fees as of January 2024 are:
• Vehicle (2-8 people): $6.00
• Vehicle (1 person): $4.00
• Extra passengers: $2.00
• Motorcycle: $4.00
• Pedestrians & bicyclists: $2.00