TEXAS · WELLS · ATASCOSA COUNTY · GUAJILLO UNIT 16 NORTH LEASE · API 42-013-35476 · DISTRICT 01

Guajillo Unit 16 North #1H

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Atascosa County · Eagleville (Eagle Ford-1) field · Producing  · Horizontal

Guajillo Unit 16 North #1H (API 42-013-35476) is a horizontal well in Atascosa County operated by Marathon Oil EF LLC, completed January 9, 2020 and listed as producing on the RRC schedule.

The RRC has issued one drilling permit, issued May 5, 2017, permitted to 11,059 ft.

Completion filings report 10 formation tops, including Queen City, Reklaw, Bartosh, Carrizo.

Its lease has reported 1.23M barrels of oil and 1.5M mcf of gas since October 2018, last reporting in July 2026. The lease carries 4 wells, so these are lease totals, not this well alone.

Operator of record

Marathon Oil EF LLC

Based in
Houston, TX
P-5 status
Active (A)
P-5 last filed
Sep 26, 2025
Permits on file
3,191
Phone
(832) 486-2737

SOURCE · RRC EWA WELLBORE SCHEDULE

What each RRC source says

Wellbore scheduleMarathon Oil EF LLC
Production reportsMarathon Oil EF LLCthrough Apr 2026
Latest permitMarathon Oil EF LLCMay 5, 2017
11,059
total depth, ft
1
permits on file
May 5, 2017
last permit issued
Jan 9, 2020
completed
1.23M
cumulative oil, bbl
1.5M
cumulative gas, mcf

PRODUCTION FROM PDQ LEASE REPORTS · Oct 2018 THROUGH Jul 2026

Regulatory status · RRC wellbore file

Schedule
ON SCHEDULE
Completed
Jan 9, 2020
Shut in
—
Plugged
—

Operator's P-5 on the schedule: Active – Extension (X)

Surface location

No coordinates on the permit record yet. The RRC's GIS record usually lands within days of issuance; historical master-file permits never carry one.

Lease production

PDQ LEASE REPORTS · REPORTED THROUGH APR 2026

Texas reports oil by lease, not by well. These are the lease this well is completed on; they carry 4 wells in total, so volumes are shared.Why →

LeaseFieldReporting operatorWellsOil, bblGas, mcfReported
Guajillo Unit 16 North O-1-19500Eagleville (Eagle Ford-1)Marathon Oil EF LLC41.23M1.5MOct 2018 – Jul 2026

Oil, barrels lease total

Last 12 months 16,347 · prior 12 36,128(-55%)

05K10K202420252026

Gas, mcf lease total

Last 12 months 40,200 · prior 12 46,723(-14%)

05K10K202420252026

Chain of custody

Every operator that reported production on this well's lease, in order.

  1. 1Marathon Oil EF LLCApr 2019 → Apr 2026

Permits

PermitTypeOperatorReceivedIssuedSpudDepth
825783-99DrillMarathon Oil EF LLCApr 21, 2017May 5, 2017Mar 10, 201919,400

Completions

CompletedLeaseFieldOperatorStatusDepth
Jan 9, 2020Guajillo Unit 16 North O-1-19500Eagleville (Eagle Ford-1)Marathon Oil EF LLCProducing11,059

Formation tops

As filed on W-2/G-1. Subsea from 256 ft elevation.Download CSV →

FormationMD ftSubsea
Queen City2,991-2,735
Reklaw3,353-3,097
Bartosh3,752-3,496
Carrizo3,993-3,737
WilcoxWILCOX - DISPOSAL5,281-5,025
NavarroNAVARRO - H2S8,943-8,687
OlmosOLMOS - DISPOSAL9,279-9,023
AnacachoANACACHO - H2S10,791-10,535
Austin ChalkAUSTIN CHALK - H2S, DISPOSAL11,042-10,786
EscondidoESCONDIDO - H2S, DISPOSAL——

Perforations

Perforated and open-hole intervals.

FromToType
11,43118,143Perforated

Casing

Strings as reported, shallowest first.

Casing inSet atHole inCement
9.6255,40112.251,732 S
5.518,2468.753,625 S

Completion filings

W-2 and G-1 reports on record in the RRC wellbore file, newest first. The suffix identifies the wellbore or completion event. About these reports →

SuffixFiledW-2 / G-1 dateLogs referenced
00May 15, 2020Jan 29, 2020Yes
00Apr 26, 2019Apr 18, 2019Yes
00Jan 23, 2019Dec 10, 2018Yes

The source documents

Petrora holds the structured record. The scanned filings live at the RRC; these links open its search already filled in for this API.

Log images are in archives with no per-well link: the RRC's Neubus archive (2004 onward). then paste it into their search.

About this data

Permits from the RRC OGA049M master and daily daf420 files; wellbore and operator of record from the EWA schedule, weekly; completions, formation tops, casing, and perforations from the dbf900 wellbore file; production from PDQ lease reports, which lag two to three months; injection from UIC permits, H-10 reports, and TexNet daily volumes; earthquakes from the TexNet catalog.

New to these records? How to read a well page · API numbers · completion reports and tops · why production is by lease

Developers: this page as JSON is GET /v1/data/wells/01335476, documented in the API reference.