Proceedings Volume Cover
SQCIEI’OYF PEI’RO- ENGINEERSOF AIME  
6300 North CentralExpressway  
Dallas,Texas 75206  
&R:SpE  
1018  
THIS IS A PREPRlIW2--- SUBJECTTO CORRECTION  
GAS PRORATION  
IN THE SAN JUAN BASIN  
By  
Emery C. Arnold,New MexicoOil ConsecratioCnommission  
PublicationR&hts Reserved  
This paper is to be presentedat the Four CornersRegionalMeetingof the Societyof Petroleum  
Engineersto be held in Farmington,N. M., on Sept. 18- 18, 1964, and is consideredthe propertyof  
the Societyof PetroleumEngineers.  
Permissionto publishis hereby restricted$0 an abstractof  
not more than 300 words,with no illustrations,unlessthe paper is specificallyreleasedto the  
press”-btyhe Edf%orof Journalof PetroleumTechnologyor %he ExecutiveSecretary. Such abstract  
shoulcicontainconspicuousacknowledgmentof where and by whom the paper is presented.  
Publication  
elsewhereafter publicationin JournalofPetroleumTechnologyor societyof PetroleumEngineers  
Journalis grantedon r:xluest,  
presentationof the paper.  
providingthe proper creditis given that publication&nd the original  
Discussionof *his paper is invited.  
Three copiesof anY discussionshouldbe sent to the Societw  
.
.
of PetroleumEngineersoffice.  
Such discussionma ~ be prese;tedat the above meetingsand considered”  
for publicationin one of the two SPE magazineswith the paper.  
shale sectionswith interveningsandstones.With.  
TNTRODUCTTON  
in specifiedareas,whereverthese sandstones  
developsufficientporosityand permeability,  
Naturalgas has been producedcommerciallyin  
the San Juan Basin of NorthweetNewMexico since  
the early 1920’s.  
late 1951, when our firstmajor market was estab-  
lishedin Californiaby the El Paso NaturalGas  
na tura l  
ga s has accumulated. For this reason,  
the occurrenceof gas is very wide-spreadgee-  
graphicallyand the dry hole ratio for devel-  
opmentwells is very law.  
Developmentwas minor until  
Ninety-fiveper cent of our naturalgas  
co.  
The PicturedCliffsSandstoneis the  
developmenthas takenplace since 1. 951.  
shallowestof the major producingzonesand rang(  
Id depth withinthe producingareas from 1,000  
As of Jan. 1, 1952,there were about 300  
to 4, 000 f t .  
There are 10 Ptcturea  
Cliffs Pools  
producinggas wells servinglocalNew Mexicoand  
as definedby the O“ilConservationCommission,  
all of which representsandbaraccumulations  
along burietishore lines. Approximately2,500  
.Asof Jan. 1, 1.964,there were  
Coloradomarkets.  
5,920wells.producinggas. Total cumulativepro-  
ductionto Jan. 1, 1964,was 2~973~010~197Mcf’o  
Theee wells  
wells are producingfrom this zone.  
were all developed on 16r)-acrsepacing.  
Mesa-  
PICTUREDCLIFFS SANDSTONE,MESAVERDEFORMATTON,  
AND DAKOTA WUWXWONE  
verde gas productioncomes from a huge, fairly  
well definedstratigraphicreservoirwhich is  
approximately70 miles long aud kO miles wide.  
Depth rangeafrom 4,000 to 6,OOO ft. Approxi-  
mately 1,900wells are now producingin the Blan.  
co hlesaverdPeool..Thie pool Is developedon  
320-acrespacingand is still,not fully developed  
Qas developmentsince 1952 has been at a  
steadyrate of from 300 to 650 wells per year at  
Ninety-  
an averagerate of 500 wells per year.  
sevenper cent of our gas productioncomesfrom  
three geologicformations,all within the Cre-  
taceousSystem. These are the PicturedCliffs  
S%ndstone,MesaVerdeF@mation and the Dakota  
San&stone.  
The thirt majorgas producinghorizon iS the  
DakotalRmmation,which varies in depth from  
6,OOO to 8,OOO ft. within the producingarea.  
The BasinDakotaPool is definedby the Co!mu.is-  
eion as betng that area which is productiveof  
gas.fromthe Dakota in San Juan$ Rio Arriba  
and SandovalCounties. Most of the productive  
The most importantcontrollingmechanismfor  
the accumulationof gas In each of these forma-  
tions is rock characteristics.The Cretaceous”  
Systemin the San Juan Basin consistsof thick  
.-,