ZONE 21-B TREND, District 04, Texas

A field is the Railroad Commission's unit of geology and of regulation. Its spacing rule is what decides how many wells an acreage can hold.

Leases

with a page here

Operators

Value, all time

$161.8 M

13% of the register's 267

Discovered

1974-12-01

Gas

Our estimate: volumes the operator filed with the Commission, valued at the EIA first-purchase price for that month. It is not a payment anyone received, and it is not a royalty. It sums the 35 leases in this field that have a page here — 13% of the register's 267 — so it understates the field.

Production, 2025

The Railroad Commission's Oil and Gas Annual Report for 2025, its most recent. These are the state's figures for the whole field, not ours.

Wells	In the field	Producing	Produced in 2025	Also produced	Cumulative
Gas	37	11	1,206,544 mcf	17,300 bblcondensate	1,349,806,595 mcfsince 1970

Spacing rule

What the Commission requires of a well on this field.

Wells	Rule	Effective	From the lease line	Between wells	Acres per unit	Max diagonal
Gas	B	2003-05-06	330 ft	660 ft	640	11,000 ft
Gas	O	2003-05-06	330 ft	660 ft	40	2,100 ft

Commission remarks: FORMULA REMAIN SUSPENDED.

County

Jim Wells County

Leases in this field

Every lease here files this field's number with the Commission and has a page on this site.

Lease	Operator	Value
KING RANCH BORREGOS	EOG RESOURCES, INC.	$61.4 M
SEELIGSON ZONE 21-B UNIT	LOGAS ENERGY, LLC	$32.4 M
KING RANCH TIJERINA	EXXON MOBIL CORPORATION	$13.6 M
SEELIGSON ZONE 21-B UNIT	LOGAS ENERGY, LLC	$9.4 M
SEELIGSON 21-B UNIT	LOGAS ENERGY, LLC	$7.2 M
SEELIGSON /ZONE 21-B/ UNIT	LOGAS ENERGY, LLC	$6.7 M
KING RANCH BORREGOS	EOG RESOURCES, INC.	$5.9 M
SEELIGSON /ZONE 21-B/ UNIT	LOGAS ENERGY, LLC	$4.3 M
SEELIGSON ZONE 21-B UNIT	LOGAS ENERGY, LLC	$2.6 M
KING RANCH BORREGOS	EOG RESOURCES, INC.	$2.4 M
SEELIGSON /ZONE 21-B/ UNIT	LOGAS ENERGY, LLC	$2.2 M
SEELIGSON /ZONE 21-B/ UNIT	LOGAS ENERGY, LLC	$2.0 M
DE TIJERINA, H.C.	AXIO PRODUCTION COMPANY, L.P.	$2.0 M
SEELIGSON ZONE 21-B UNIT	LOGAS ENERGY, LLC	$1.9 M
KING RANCH TIJERINA	EOG RESOURCES, INC.	$1.5 M
KING RANCH BORREGOS	EOG RESOURCES, INC.	$1.4 M
SEELIGSON/ZONE 21-B/UNIT	LOGAS ENERGY, LLC	$1.3 M
DE TIJERINA	REMORA OPERATING, LLC	$949 k
KING RANCH BORREGOS	EOG RESOURCES, INC.	$771 k
STEWART - JONES UNIT NO. 2	MOBIL PRODUCING TX. & N.M. INC.	$719 k
KING RANCH SEELIGSON	EXXON MOBIL CORPORATION	$272 k
KING RANCH TIJERINA	EOG RESOURCES, INC.	$256 k
KING RANCH BORREGOS	EOG RESOURCES, INC.	$223 k
CANALES, A. T.	REMORA OPERATING, LLC	$101 k
KING RANCH TIJERINA	EOG RESOURCES, INC.	$87 k
KING RANCH BORREGOS	EOG RESOURCES, INC.	$72 k
SEELIGSON, A.A.	SUE-ANN OPERATING, L.C.	$56 k
WILKINSON, A. D.	LOW-END OIL LLC	$42 k
KING RANCH BORREGOS	EOG RESOURCES, INC.	$26 k
CANALES, A.T.	FOREST OIL CORPORATION	$23 k
DE TIJERINA, H. C.	REMORA OPERATING, LLC	$11 k
DE TIJERINA, H. C	CHESAPEAKE OPERATING, INC.	$8 k
DE TIJERINA, H.C.	REMORA OPERATING, LLC	$6 k
KING RANCH BORREGOS	EXXON CORP.	$5 k
BLUCHER, C.F.H.	MOBIL PRODUCING TX. & N.M. INC.	—

Field number 99880380, from the Railroad Commission's field register. The register's own index resolves 267 leases and 267 wells to this field by name, over every lease in Texas rather than only those with a page here. It resolves a lease by NAME and refuses an ambiguous one, so it counts nothing for a field that shares its name with another — which is why the lease count above comes from the field number instead.