September 21 – Cross-Bedding in Sedimentary Rock
When traveling in the western states, you may come across cross-bedding. Cross-bedding is found in sedimentary rock; it is a series of visible layers within the rock that suddenly change direction. Most layers are horizontal; however, cross-bedding has layers that are at a distinct angle to the horizon. Cross-bedding is found most often in sandstone. Cross-beds exist because of Noah’s Flood.
Desert sand dunes have steep faces with sand beds at an angle greater than 25 degrees. If the sand bed angle is less than 25 degrees, most likely it was water-deposited. By measuring the angle of the sand layers in these cross beds, we can determine if the sandstone came from an ancient desert or a flood. You can do an experiment to establish whether a cross-bedded sand dune was created by wind or water. First, establish the horizon, lay a protractor on that, and determine the angle of the cross-bed. If the angle of the sand bed is greater than 25 degrees, it formed in a dry environment. If the angle of the sand bed is less than 25 degrees, the sand was most likely laid down in a flood environment. If you do not have a protractor with you, take a picture and do the measurements at home. It is the wide extent of cross-bedding throughout sandstone layers of the western United States that testify to the worldwide nature of the Flood that laid these rock layers down. So, the next time you visit national parks in the West, take along your protractor, and do the protractor test. Sedimentary rock layers with cross-bedding are a testimony to Noah’s Flood!
Psalm 139:12-18
Reference
Thomas, Brian. September 2014. “Do Sand-Dune Sandstone Disprove Noah’s Flood?” Acts & Facts. I.C.R.: Houston, Texas. p. 18-19.
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