a modern continental configuration for easier comparison of the megasequences through the Flood year. We also created basal lithology (rock type) maps for teach of the megasequences. We assumed the basal layer would be the bestpreserved unit in each megasequences and give us the most accurate sedimentological information for the start of each new megasequence. Many megasequences were found to begin with a sand-rich layer at the base, but that was not always the case. Once we had the extent and thickness maps for each megasequence across each continent, we used RockWorks to compile the total rock volume and surface area for each continent and also for each megasequence (Table 1). This included totals for the five continents combined. All rock volume data are recoded in cubic kilometers. Surface areas are reported in square kilometers. Thickness and extent maps for each of the six megasequences across the continents, and the total volumes in each megasequence, demonstrate that the earliest three megasequences exhibit the least areal extent and lowest sedimentary volume (Figs. 7-9 and Table 1). Subsequent megasequences (Absaroka and Zuni; Figs. 10-11), show significantly more land coverage and more sediment volume. Most Surface Area (km2) North America South America Africa Europe Asia Total Sauk 12,157,200 1,448,100 8,989,300 5,149,800 17,775,800 45,520,200 Tippecanoe 10,250,400 4,270,600 9,167,200 5,208,200 11,881,100 40,777,500 Kaskaskia 11,035,000 4,392,600 7,417,500 8,121,900 16,262,800 47,229,800 Absaroka 11,540,300 6,169,000 17,859,900 11,401,700 28,733,900 75,704,800 Zuni 16,012,900 14,221,900 26,626,900 9,940,300 33,162,200 99,964,200 Tejas 14,827,400 15,815,200 24,375,100 9,568,000 34,187,200 98,772,900 Total 26,572,700 20,965,800 35,591,100 18,272,600 59,229,500 160,631,700 Volume (km3) North America South America Africa Europe Asia Total Sauk 3,347,690 1,017,910 6,070,490 4,251,000 18,730,330 33,417,420 Tippecanoe 4,273,080 1,834,940 6,114,910 3,236,310 9,118,960 24,578,200 Kaskaskia 5,482,040 3,154,390 3,725,900 10,387,180 15,733,730 38,483,240 Absaroka 6,337,270 6,073,710 21,222,750 26,682,700 48,596,470 108,912,900 Zuni 16,446,210 23,202,680 57,756,300 16,160,960 78,157,140 191,723,290 Tejas 17,758,530 32,973,060 28,855,530 18,936,550 92,732,160 191,255,830 Total 68,138,990 70,481,840 140,121,460 83,003,340 282,912,980 644,658,610 Average Thickness (km) North America South America Africa Europe Asia Total Sauk 0.275 0.703 0.675 0.825 1.054 0.734 Tippecanoe 0.417 0.430 0.667 0.621 0.768 0.603 Kaskaskia 0.497 0.718 0.502 1.279 0.967 0.815 Absaroka 0.549 0.985 1.188 2.340 1.691 1.439 Zuni 1.027 1.631 2.169 1.626 2.357 1.918 Tejas 1.198 2.085 1.184 1.979 2.712 1.936 Total 2.564 3.362 3.937 4.543 4.777 4.013 Table 1. Surface area (km2), volume of sediment (km3), and average thickness (km) by individual continent and by individual megasequence, including total values for all five continents. Surface area totals and average thickness totals are affected by overlap and/or missing megasequences. continents show a maximum peak in both coverage and volume in the last few megasequences. Differences may be related to the preFlood topography (Clarey 2019b). For this reason, we created a new diagrammatic sea level curve that better matches the rock data (Fig. 13). We also constructed a graph of the percent volume deposited by megasequence (Fig. 14) and a graph of the percent total surface area covered by each megasequence across the five continents (Fig. 15). V. DISCUSSION A. New Global Sea Level Curve Vail et al. (1977) first identified global sea level as the dominant driving mechanism for megasequence development. Megasequences are thought to have formed as sea level repetitively rose and fell, resulting in flooding of the continents up to six times in the Phanerozoic (Sloss 1963). Upper erosional boundaries were created as each new sequence eroded the top of the earlier sequence as it advanced. The result was the uniformitarian global sea level curve for the Phanerozoic (Fig. 1). To construct this curve, Vail et al. (1977) and Haq et al. (1988) CLAREY AND WERNER Progressive Flood model 2023 ICC 422
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