Except they weren’t searching. The facts you relate are ex post facto. Meaning: if you know you have stumped your toe after you stump your toe. . None of the Shell geologists had a clue of what they were dealing with until the independents started poking hole sin the ground. Ironically, they knew more about the deep formations they are now exploring than that did the sands in which oil was. Had been drilling in the La fields of course and the East Texas field lay to the west off the map. Anyway, a better place to look at is the appalachian fields, with their proximity to other “fossil” deposits. The deeper these fields get, the more one wonders how the deposits got there.
I don't know why you think that. Searching for oil in East Texas goes back to the Civil War time period. Oil Springs was named after the oil forming on the water indians had used far before that.
Boynton from the Gulf Production Company brought together people in Rusk county to search for oil in 1911. Columbus Marion “Dad” Joiner drilled a couple wells without success before his historic well produced. I don't know why you consider this by accident.
The deeper these fields get, the more one wonders how the deposits got there.
You do understand don't you that these deep layers are still sedimentary layers? And the beneath sedimentary layers, regardless of how deep or shallow, oil and gas has not been found.
THE HISTORY OF THE EAST TEXAS OIL FIELD
http://www.texasranger.org/E-Books/History_of_the_East_Texas_Oil_Field_(Silvey).pdf
This was the Master Thesis of Lucile Beard written in 1938, when the discovery of the field was still relatively current but the production had grown immense. Martial law was declared, overruled and the politics and economics became quite a mess.