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WESTERN N. AMERICAN SEDIMENT ORIGINS IN EASTERN N. AMERICA (OR EAST OF AFRICA?)
Long-distance transport of sediments
https://creation.com/long-distance-tran ... -sediments
Sand transport for thousands of kilometres
_In 1992, Rainbird et al. deduced that sands in sandstones from various areas of north-west Canada mostly originated from south-eastern North America, travelling from one side of North America to the other.5 The sediments analyzed were originally deposited in two arcuate Precambrian basins — the Mackenzie and the Amundsen basins. These basins contain thousands of metres of sedimentary rocks.... Portions of the basins have uplifted into mountains, where the sedimentary rocks can be sampled. The paleocurrent directions in the sandstones are also consistently from the south-east, supporting their conclusions.
_... in their most recent research they ... obtained the same results (though more local sources were found in the lowest sandstones just above the upper crustal igneous and metamorphic rocks). They found sand grains embedded throughout considerable thicknesses of strata, over 4,000 m thick in the Amundsen Basin, likely originated from the area of the Grenville orogeny and other faraway Precambrian terranes near the Appalachian Mountains, about 3,000 km [2,000 mi.] away. They emphasize that the ‘river’ or ‘rivers’ that flowed toward the north-west were at least 1,200 km [800 mi.] wide! This is “much wider than any modern fluvial system on Earth”.7
_Rainbird et al. claim that the sand had travelled such long distances based on the ‘ages’ of zircon crystals in the sand.
_Sandstones of south-west North America and Alberta also mostly from Grenville orogeny
_Not only are the sand and other sediments of north-west North America believed to have originated from eastern North America, but so are most of the sands in south-west North America and Alberta.12
_Neoproterozoic and Cambrian strata in the south-west United States and north-west Mexico are believed to come from the Grenville orogeny....14 In this case, the nearest Grenville terrane is in Texas about 1,000–1,500 km away [700-900 mi.].
_The huge Permian and Jurassic ‘eolian’ sandstones on the Colorado Plateau of the south-west United States are believed to have blown in from the north, as far as Canada, according to paleocurrent directions. Nearly half of the original sand is believed to have been transported 1,000–2,000 km from the east, from around the Appalachian Mountains. 15-17 Rainbird et al. think this westward-transported sand was then picked up by northerly winds and spread into south-west United States. Most of the upper Paleozoic sands from Grand Canyon are also thought to have come from the Appalachian region and been spread by large rivers.18 Some of the strata from the western Canadian Sedimentary Basin in Alberta are also deduced to have come from the Grenville orogeny and the Appalachian area.19 It appears all the sandstones (as well as other sediments) from north-west Canada to north-west Mexico originated from the eastern part of North America.
_Unfortunately for the secular model, evidence for their postulated ancient transcontinental rivers does not show up in the sedimentary rocks of middle North America.20
_[An] explanation ... is that the sand and other sediments were transported westward long distances over wide areas during the Genesis Flood. This evidence is better explained by wide, fast water currents picking up the sand and depositing it during the Flood. All this sediment in western North America transported from eastern North America does imply a large mountain uplift in the east.
_... it seems this cataclysmic sediment transport would better fit the early part of the Genesis Flood.22
RELATED ARTICLES
Colorado Plateau sandstones derived from the Appalachians?
https://creation.com/colorado-plateau-sandstones
Granite formation: catastrophic in its suddenness
https://creation.com/granite-formation- ... suddenness
THINKING ABOUT SEDIMENT ORIGINS
_In the first article above, Oard said: "All this sediment in western North America transported from eastern North America does imply a large mountain uplift in the east."
_Mike Fischer's model at
https://www.newgeology.us/ says the Shock Dynamics asteroid impact that broke up the supercontinent and caused rapid continental drift and mountain building occurred a few centuries after the Great Flood. But I mentioned to him a few years ago that Oard, I think, said the Grand Canyon formed during the recession stage of the Flood, which makes sense to me, and I think it had to form as the Colorado plateau was uplifting. So the asteroid impact and rapid continental drift and mountain building had to occur during the Flood. But it only took one day for the Rockies to uplift after the Appalachians uplifted, which would be way too fast for the waters from the East to deposit sediments in the West and immediately uplift the western sediments too.
_It appears, therefore, that Oard was wrong about mountain uplift in the East causing the sediment flow to the West. The Atlantic must not yet have formed and the waters that carried eastern sediments to the West must have come from southeast of Africa via tsunamis.
_PS, another important point Mike Fischer made is that the Flood sediments hardened pretty strongly because the atmosphere was reduced by impacts and degassing caused CO2 to combine with calcium to form lime, which acted as a cement for forming rock from the sediments. And Cardona has an explanation in one of his books about how impacts would remove portions of the atmosphere.
HEIGHT & VELOCITY OF SOME FLOOD WAVES
Startling evidence for Noah’s Flood: Footprints and sand ‘dunes’ in a Grand Canyon sandstone!
https://creation.com/startling-evidence-for-noahs-flood
_ Coconino Sandstone (see Figures 1 and 2). It is estimated to have an average thickness of 96 m (315 ft) and, with equivalent sandstones to the east, covers an area of about 519,000 sq km (200,000 sq miles).2 [It covers northern Arizona, northwest Colorado, Nevada, and Utah.]
_The thickest sets of cross beds in the Coconino Sandstone so far reported are 9 m (30 ft) thick.16 Cross beds of that height imply sand waves at least 18 m (60 ft) high and a water depth of around 90 m to 95 m (300 ft). For water that deep to make and move sand waves as high as 18 m (60 ft) the minimum current velocity would need to be over 95 cm per second (3 ft per second) or 3.2 km (2 miles) per hour. The maximum current velocity would have been almost 165 cm or 1.65 m per second (5.5 ft per second) or 6 km (3.75 miles) per hour. Beyond that velocity experimental and observational evidence has shown that flat sand beds only would be formed.
_Cross beds within the Coconino dip consistently toward the south, indicating that the sand came from the north.
_Consequently, this enormous volume of sand would have to have been transported a considerable distance, perhaps at least 320 km to 480 km (200 or 300 miles). At the current velocities envisaged sand could be transported that distance in a matter of a few days!
SOME MAINSTREAM INFO ON SEDIMENT ORIGINS
A review of fine-grained sediment origins, characteristics, transport and deposition
https://sp.lyellcollection.org/content/15/1/17
_Fine-grained sediments and sedimentary rocks make up as much as 75% of the present and past sedimentary records. River [or Tsunami?] discharge is the largest single source of fine-grained material, followed by biological, volcanic and aeolian sources.
HOW DELICATE FOSSILS FORMED
Are soft-sediment trace fossils (ichnofossils) a time problem for the Flood?
https://creation.com/images/pdfs/tj/j20 ... ion_detail
_... zones of rapid lithification alternated with Flood deposition, thus temporarily protecting deeply-buried organisms from the immobilizing effects of thick sediment overburden. This allowed for the simultaneous bioturbation of considerable thicknesses of Flood sediment soon after its deposition.