Some technical infoOK, here's what I've learned so far reviewing comments and asking questions on a FB group called Rig Pics where rig hands post pics and comment: The Eagle Ford has soft formations all the way down to TD. They can drill 20,000 foot wells (spud to TD) in 10 days. From the vertical section they can build angle and drill the horizontal section with one bit.
So the producing zone must be soft. My guess is that it's probably some porous, yet tight, fine grained siltstone/sandstone/carbonate but not rock made up of many clay type minerals. Supporting that interpretstion is the fact that for them to knock out these wells in 10 days then must must be tripping pipe into and out of the hole at a very high rate. For them to do that then they're obviously not worried about swabbing in a kick or creating hole instability problems like sloughing shale. They then frac the formation in order to open up flow paths for oil to flow to the producing wells.
If the above is indeed the geology of the Eagle Ford, then it has some pretty positive implications in that the rock is such that it might be possible to water/polymer flood it in order to produce much more OOIP (original oil in place). I keep on reading that the water/polymer flooding of shale wells is the next big boom. The call it the next "shale revolution".
Right now the Eagle Ford has only had between 8% and 10% of its OOIP produced. If they can water/polymer flood the Eagle Ford then they reckon that they can recover up to 30% of the OOIP. In other words hundreds of millions of barrels more recoverable reserves if they can unlock that value. So let's see if they can pull it off.
I could go into much more technical detail but I first want a block button.