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What I don't understand is why there is no Tex under TK in the fault block. If the section was drawn up before 1999 maybe they didn't look hard enough. TK is older Tertiary and Cretaceous formations. Perhaps TK to the left is Cretaceous, but TK over Tex has to be younger than 34my. Te, marine, sand and clay, may have been the deposition over the entire area as marine sediments covered the disaster area.

I more or less follow what you're saying, but if you're basing your opinion on this particular graphic, there's always the possibility the graphic itself is not all that accurate; maybe more of a generalized stratigraphy representation. I dunno. It would probably take some detective work to determine that but I'm not up to the task.

Of course the age of TK in the fault block and the age of Te would be useful information.

Probably so, but I can't follow the timeline, presuming there is one even implied in the graphic. The labels of the different layers don't even register with me. IOW, I can't make heads or tails out of it ;^)

"The labels of the different layers don't even register with me."

Let me see if I can make it a little more clear. Start with "Igneous and Metamorphic Basement". (This is very old bedrock formed by volcanic activity or extreme pressure.) It has been eroded over time, and then various layers of sedimentary rock have been deposited on it at different times. Normally, the lower layers are older than the layers above.

Now, let's find a layer we can date either by knowledge or description. Cretaceous refers to a time before 65 million years ago. Older Tertiary refers to time after 65 mya, but still a long time ago. Quarternary refers to the time of the Ice Ages, less than two million years old. The one formation that I can date by knowledge is Tex - Exmore Breccia. This jumble of broken rock (breccia) was formed by the great Chesapeake boloid which struck about 34 million years ago, when all the debris fell back into the great crater. Since Poag an associates first published their hypothesis that the breccia was crash debris in 1995, anything older and even for a few years after would not include that concept in its charts and literature. Now it is well accepted by people working in that area.

At any rate, back to the chart. The fault lines to the right were caused by slumping along the rim of the great crater. The age of TK in the slump block is unknown, and the lack of Tex is puzzling. The TK over Tex has to be younger than 34 million years, as does Te and Ty. Since the fault lines extend up into Te and part way into Ty, then the block must have continued to slip over an extended period of time. I hope this makes things a little clearer.