The Brunswick permit states 17100' as the planned total depth which indicates a vertical hole. I'm assuming that the horizontal details will be added later. If not, then this could be a vertical pilot hole where conventional core might be obtained. At the surface location, the Base of the Austin Chalk should occur at approximately 16788' measured depth which provides about 300' of "rat hole". This will be their deepest well to date. Upon completion, EOG will have one well in each of their three lease areas.
As I detailed in a prior post on the "regions" across the play, this downdip area has much more complex geology than that of the updip fairway. Growth faults, that were initiated during the time of Tuscaloosa sand deposition, pose potential limitations on lateral length due to the fact that one wouldn't want to drill across a fault with throw ranging from 100-300'. The surface location of the Brunswick #1 is directly north of the first Tuscaloosa expansion fault. The geologic complexity increases dramatically south across that fault. EOG's lateral will occur between the Fredericksburg Shelf Edge and the first Tuscaloosa expansion fault. A local fault to the north traps a small accumulation of gas in the Tuscaloosa sands to the east. The structural dip orientation in the block might lead EOG to orient the lateral directly up structure. Another aspect of the downdip fairway is that dip direction changes within fault blocks.
The Chesapeake Schexnayder #1, an Austin Chalk horizontal well, was drilled in July, 1997 (3.65 miles east). It had an initial potential of 768 bopd and 300 mcfgd. It produced only 32 MBO and 8 MMCFG. This well was drilled during Austin Chalk 2.0 in the 90's when the theory was to drill an open hole lateral across natural fractures. From these well results, one might conclude that the well didn't intersect many oil saturated fractures.
Most significant, the Amoco Beaud #1 (2.1 miles east) drilled through the Austin Chalk. The logs reveal 85' of high resistivity, high log-calculated TOC, and oil saturated chalk/marl section. The bottom 150' of the Austin Chalk averages 3% on the density porosity log with "spikes" up to 6-7%. This location has lower porosities than that of the EOG Ironwood 37H-1, but is more likely to have natural fractures, higher pressure, and more natural gas. All three of those factors can assist with oil production.
The lowest 40' in the Austin Chalk appears to be very chalky which should present a good "landing zone". The interval above presents a cyclic chalk/marl sequence very similar to that seen in the Marathon Todd #1 core. The frac should be designed to impact the bottom 85' of the section.
This will be an exciting exploratory well. The "downdip" players (Devon, Marathon, Petroquest, Torrent, Blackbrush, and Cimarex) will be watching closely.