With the development of global paleogeographic reconstructions, it is possible to examine the original distribution of carbonate buildups at various times in the earth's history. Through an extensive search using published geologic literature, carbonate buildups have been classified based on their association with shelf-edge, shallow-shelf, and basinal sediments. By plotting the data on well-constrained Mesozoic and Tertiary paleogeographic continental reconstructions, it is observed that carbonate buildups are generally restricted to low latitudes. However, the maximum excursion of buildups from the paleoequator varies significantly through geologic time.

The distribution and abundance of carbonate buildups in the Mesozoic and Tertiary appear to be partly controlled by ancient ocean current systems. In a manner similar to the present, carbonate buildups extend further toward the poles along east-facing coastlines. Here, warm westward-flowing

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equatorial currents are diverted poleward. The reverse situation is true along west-facing coastlines where cooler waters are brought into low latitudes by polar currents. Here, buildups are usually restricted to near the ancient equator. Another control on the distribution of carbonate buildups might be related to a decrease in light penetration poleward due to an increase in the angle of incidence of light striking the oceans. Work done by others suggests that significant seasonal reduction in light penetration occurs between 30° and 40° from the equator.

Maps showing the global distribution of carbonate buildups have been constructed for several intervals in the Mesozoic and Tertiary. These reconstructions illustrate the effects of ocean circulation, and continental placement and orientation on the distribution of carbonate buildups.

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