1. Grand Canyon Cambrian Tapeats Sandstone: How was it deposited?
Research by Arthur Chadwick, PhD
Collaborators from Geoscience Research Institute and Loma Linda University

2. Research approach:
A good theory in science is one that successfully predicts the outcome of untried experiments
Bible can be used to give direction to research efforts in a manner that will yield better results than the standard model
Scientists following the Standard Model (millions of years of evolutionary time) have suggested a layer of sandstone in Grand Canyon – the Tapeats Sandstone - was deposited in shallow water over millions of years
Biblical model suggests Tapeats may have been deposited in deep water rather quickly

3. Events at the Grand Canyon
1. Deposit the Tapeats Sandstone
Slow, or rapid?
2. Deposit the rest of the sediments
3. Cut the Canyon
Standard model – many millions of years
Biblical model – could have been rapid

4. Cambrian Sediments in Grand Canyon
Uppermost Cambrian - Muav Limestone
Below this - Bright Angel Shale
Below this - Tapeats Sandstone = lowest Cambrian sediment in the Grand Canyon region
Coarse-grained quartzose sand
100 meters thick
Described as Middle Cambrian

5. Standard model explanation of the Tapeats:
Shallow transgressing sea
Getting deeper and moving shoreward; suggested multiple cycles of deeper, then shallower
Based upon “shallow water” sedimentary structures
Based in large part on comparisons with modern environments

6. Locations of our observations
10 mi

7. The surface the Tapeats Sandstone was deposited upon was mostly flat, but one very large cliff was present

8. Below the cliff (background) the Tapeats was deposited with or upon a thick layer of angular rocks (breccia)

10. Relationship between Precambrian cliff and breccia prior to Tapeats deposition

16. If it had taken millions of years for the advancing sea to deposit the Tapeats, the sea waves would have destroyed the breccia and the cliff as well

17. The water had to be deep enough to cover the entire breccia slope all during the deposition of Cambrian sediments – to protect the breccia and the cliff from destruction

18. Comparison of the models: 1
Comparison of the models: Standard model – slow, shallow marine deposition in advancing sea 2. Revised model – rapid deposition in deep water

19. Standard model

23. Revised model

29. Conclusions : Tapeats was not deposited in a shallow setting.
Deposition was in deep water, and was rapid.
Sedimentary structures used to define Tapeats as shallow marine need to be reevaluated in the light of these findings.

30. Conclusions :
Research motivated by a biblical worldview resulted in notice of features not recognized by other geologists
Careful geological research confirmed the revised interpretation