Thank you for the question on the formation of the earth, “Is it possible that the plate tectonics were created during Noah’s flood and were still shifting after for a while longer?”
According to Genesis 1:9–10 that verse says this, “9 And God said, “Let the water under the sky be gathered to one place, and let dry ground appear.” And it was so. 10 God called the dry ground “land,” and the gathered waters he called “seas.” And God saw that it was good.” (A searchable online Bible in over 150 versions and 50 languages). Bible citations are in the New International Version.
The Scriptures depict that the earth was submerged under the water. Geologists have pointed out that there are sea life form on mountain tops as Mount Everest, The Rocky Mountain, as well as the Andes Mountain Range. In my opinion, if the earth was not submerged underneath the waters, then there wouldn’t be any sea life on the mountain tops. In other words, the presence of sea life may well indicate that the earth land mass was submerged underneath the waters.
When God commanded the dry land to appear, the water must have receded into the earth. Today geologists are postulating that there may be as much water in the earth’s crust as there is water in the ocean. See for example this website or others: Is there water underneath the earth’s crust. God further commanded to let the dry ground appear. The height of the land mass arising is not stated. This appearance of the land above the water may be considered what is called the tectonic shifts in the early formation of the earth.
The Flood in Genesis 6–9 may have increased the tectonic shifts as the Scriptures described this event in Gen. 7. The text says this, “11 In the six hundredth year of Noah’s life, on the seventeenth day of the second month—on that day all the springs of the great deep burst forth, and the floodgates of the heaven were opened. (NIV). The releasing of the springs of the great deep of the earth bursting forth would most likely affected the ocean floor and the land mass depending on the location of the waters bursting forth.
As a side comment, it is interesting to note that the Scripture description of the formation of the earth has some correlation with geologists description of the earth.
SUMMARY: From a Scriptural point of view, the “tectonic shifts” happened in the early formation of the earth and increased during the time of the Flood.
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