The following events are arranged in order:First was Ptolemy's Map based on description from Ptolemy's own book Geographica which is dated c. 150 AD.
Second is Columbus landing in the Bahamas in 1492.
Thiirdly would be Piri Reis map dated1513.
and lastly would be the Mercator projection dated 1569.
The anticlines represents ridges or folds of stratified rocks, with the strata being sloping downwards from the crest.
The synclines represent through or folds of stratified rocks, with the strata being sloping upwards from the axis.
Both of these features are formed in the same manner, by compression. They are also part of a same geological occurrence. Both of them are curved, and seen from side perspective, they are representing one whole, and they look like a wave.
The difference is mainly that the anticlines are always above and they slope downwards, while the synclines are always on the bottom and slope upwards.
