Sloss geological sequence (also called “megasequence”) diagrams result from observation of actual geological data—as opposed to the largely abstract “geologic column.” Since especially the 1960’s and ‘70’s, oil company geologists have drilled boreholes down through the sedimentary layers, down to basement rock—thus, providing us with actual cross-section data of these layers.
What geologists, like Lawrence Sloss (1963), have discovered are discrete “packages” of sedimentary rock layers—primarily, sandstone, shale, and limestone—bounded above and below by “unconformities,” that is, erosion zones. More specifically, they have found six of these distinct “packages” on every continent that has been explored.
And such data has told a story of earth’s ancient history. According to Walther’s Law of sedimentary deposit, the data has revealed six cycles of “transgression” and “regression.” That is, six cycles of ocean water “transgressing” over the continents to varying degrees (and Sloss focused only on North America), then “regressing” back; in fact, the data shows the North American continent was completely covered by ocean water during at least three of these megasequences. Study the diagram at Sloss's Second Order - SEPM Strata
The most popular interpretation of this data is according to the uniformitarian model—that is, such floodings occurred throughout the Phanerozoic-- from about 542 million to 66 million years ago; and the floodings were caused by slowly, slowly rising and falling ancient (“epeiric”) seas. However, I believe the megasequence data is better explained by the biblical Flood model of a series of powerful, catastrophic tsunamis transporting and depositing the massive amounts of ocean sediment we find upon the continents—tsunamis set off by plate tectonics (Genesis 7:11)…over a one-year period.
Let’s discuss the pros and cons of each interpretation…