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Map Of the Month

For this discussion we're zero'd in on Lea and Eddy Counties in New Mexico, the source of 33% of all Permian tight oil production. Everybody by now should know where Lea and Eddy Counties are, left, above.

High grading Tier 1 & 2 stuff is still the order of the day. In 2021-2022 when we were over $100 oil and $5 natty...nobody wandered far from their sweet spots; now, as gas and NGL's have come way down, more wells are being drilled in crowded places. When you look at this map you can begin to see where those sweet spots are by the intense cluster of green and red dots...but you have to look with the productive limits of the Bone Springs/Wolfcamp HZ play, with is pretty much confined to the SW corner of Lea and SE corner of Eddy, see below. For instance its a good idea to ignore semi-circular reef play in northern Eddy County. There are "unconventional" HZ wells up there but its not the stuff everybody is focused on

All the little yellow dots are pending drilling permits, a surprising number of which have been canceled or are still pending after a year or more. But those little yellow dots are confined to areas in SW Lea County suggesting, again, that nobody wants any part of the 3 and 4 stuff.

Why in this map most all of the Central Platform is labeled Tier 2 in the HZ play (?) is beyond me.

The Map of the Month above is good because it shows clearly how large undrilled sweet spots are in Lea and Eddy Counties because of potash and Federal (BLM) control over those mining areas, left. This stuff can be leased and drilled through, but if you mess up the potash mining the Feds will have you whacked.

Use this map on the right to correlate to the Map of the Month at the top to get a better idea of the productive limits of Delaware Basin Bone Springs and Wolfcamp HZ play. This is a good map for liquids gravity production and shows where in the Delaware the +51 light oil is, that is getting lighter, and creeping to the east northeast.

This map and the one below might give you some idea of why Reeves County in Texas is already in decline.

On the left is another good map of the Delaware Basin delineating the current productive limits of the HZ play.

This is important because it shows how GOR increases in New Mexico from the east to the west. This map is several years old, it would look different today because the upper two benches in the Bone Springs, and they upper two benches in the Wolfcamp, the four that get the majority of wells drilled in them, are getting gassier.

This map on the right is important too because when compared with the Map of the Month it clearly shows how many thousands of vertical conventional wells lie in the eastern part of Lea county, on the Platform, and in north Eddy County in the Capitan Reef Complex and even farther north on the shelf margin of the sub-basin (backreef). Eastern Lea County has had large fields like Hobbs and Eunice that produced from San Andreas and Grayburg There are several thousand wells in both Lea and Eddy Counties that have nothing to do with the Bone Springs and Wolfcamp HZ play. These wells make appreciable amounts of oil and little gas. And lots of water. There are currently 10,200 some odd producing HZ wells (Novi), some approaching 9 years old,* in Lea and Eddy Counties and appear to be over 14,400 total active producing wells in the same counties. Lots of HZ wells in the area have OWR of <15%.

GOR is essentially a diagnostic metric for individual well performance and now, in the HZ play, a metric used to determine the health and well being of densely drilled sweet spots. Using gas over oil for an entire country is meaningless if trying to analyse tight oil. Initial GOR's in these two counties do not appear to be getting higher, but rise as the well gets older; And, lest us not forget, that in solution/depletion gas driven shaley carbonate containers (SRV's), as the well depletes gas goes up, oil goes down, and then gas goes down.*

Clearly there is still room to run in Lea and Eddy counties from the standpoint of space, but we need to put a big question mark on all that potash stuff. What's left will be gassy and the liquids will be light. And pretty much all of it exported to foreign countries. But when Lea and Eddy Counties get to the Tier 3 & 4 stage, unless oil is $150 and gas $+5, or D & C costs go down to 1990 levels, the Permian Basin HZ play will be on the downhill slide. Personally I don't believe much of that "fringe" stuff will ever be drilled, regardless of product prices. Knowing its there has sure caused a lot of people relief, however.

Maps are cool and often just as, or more informative as charts with bad input data.


This is a USGS groundwater monitor well in the Pecos River Drainage Basin in Eddy County, in the guts of the Bone Springs fray. We better all start worrying about water in arid West Texas and New Mexico. Or perhaps I should suggest that the Netherlands and Great Britain need to worry, since it's pretty much their oil.


Food for thought from Oily Stuff. We urge you, strongly, to gather as much stuff as possible and think for yourself. Sometimes that means breaking from the flock.

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