Abundant evidence supports the major contentions of the seafloor-spreading theory. First, samples of the deep ocean floor show that basaltic oceanic crust and overlying sediment become progressively younger as the mid-ocean ridge is approached, and the sediment cover is thinner near the ridge.irst, samples of the deep ocean floor show that basaltic oceanic crust and overlying sediment become progressively younger as the mid-ocean ridge is approached, and the sediment cover is thinner near the ridge.
Polk County Weather. The average temperature of Polk County is 72.96Â°F, which is higher than the Florida average temperature of 71.80Â°F and is much higher than the national average temperature of 54.45Â°F. Historical Weather. Heating Cost Index, #14.
Florida became a state in 1845, and Polk County was established in 1861. After the American Civil War, the county seat was established southeast of Lakeland in Bartow.