FORMATIONS · RRC WELLBORE FILE

Caprock

Reported as a top in 721 wells across 19 counties, at a median depth of 1,073 ft (564 to 3,190 ft in most wells). 22 of those wells were permitted in the last three years.

A well counts if any of its completion filings report this formation, whether it produces from it or drilled through it. Depths are measured depth as filed; typo depths exist, which is why ranges are percentiles, not extremes. About completion reports →

721
wells reporting a top
22
permitted in last 3 years
19
counties
1,073
median top, ft

COMPUTED OCT 29, 2026 · REBUILT DAILY

Depth by county

Counties with at least five wells reporting the top. Bars are well counts.

CountyWellsMedian, ftP10–P90Last 3 yrs
Chambers
175
750493–1,3367
Brazoria
125
863580–1,9083
Hardin
89
1,550980–3,3813
Jefferson
66
1,068312–1,5922
Liberty
51
815325–2,6601
Washington
49
2,4102,410–3,3940
Matagorda
46
2,1001,725–2,5105
Harris
37
84030–2,5260
Fort Bend
25
3,5803,167–3,7460
Waller
23
1,9001,900–3,3560
Wharton
10
1,588653–2,8080
Smith
8
682622–7030
Milam
5
696696–6960

Operators

Current operator of record for wells reporting the top, ranked by wells permitted in the last three years.

Recently permitted wells reporting the Caprock

BY LAST PERMIT ISSUED

Last permitLeaseOperatorCountyTop, ftAPI
Mar 9, 2026Smith, Lewis Edwin et ALUnderground Services Markham,llcMatagorda2,56632132464
Nov 5, 2025Energy Transfer FuelEnergy Transfer CompanyAnderson1,31400132868
Oct 30, 2025H. SmithUnderground Services Markham,llcMatagorda1,58032132463
Jul 14, 2025BunkPonderosa Oil & Gas, LLCMatagorda2,10032132444
May 16, 2025FeeTarga Downstream LLCChambers66807132680
Apr 9, 2025Tarver HardinRadco Operations, L.P.Hardin2,27519933661
Apr 3, 2025NorrisPonderosa Oil & Gas, LLCMatagorda2,10032132437
Feb 24, 2025Central Storage TerminalMont Belvieu Caverns, LLCChambers71707132679
Jan 23, 2025Lone Star NGL MB Central TermEnergy Transfer MT Belv Ngls LPChambers96407132678
Dec 19, 2024Gulf Chambers FeeDrum Oil & Gas, Inc.Liberty81029132965
Nov 25, 2024Bennett EstateHG Operating LLCBrazoria58003933223
Oct 31, 2024Lone Star NGL MB Central TermEnergy Transfer MT Belv Ngls LPChambers1,00907132677
Oct 8, 2024Bennett EstateHG Operating LLCBrazoria50003933325
Sep 17, 2024NorrisPonderosa Oil & Gas, LLCMatagorda2,10032132427
Aug 23, 2024Central Storage TerminalMont Belvieu Caverns, LLCChambers61607132674
Jul 30, 2024Golden Triangle StorageGolden Triangle Storage, LLCJefferson1,02024532915
Jul 30, 2024Golden Triangle StorageGolden Triangle Storage, LLCJefferson93124532916
Jul 26, 2024Mont Belvieu StorageExxonmobil Pipeline Company LLCChambers1,27607132673
Jun 11, 2024Feldman, D. D. FeeSaratoga Production Company LLCHardin1,35519933658
Jun 5, 2024Feldman, D.D. FeeSaratoga Production Company LLCHardin1,75419933657
May 24, 2024BM-Mow-1U.S. Department of EnergyBrazoria78303933365
Feb 22, 2024FeeTarga Downstream LLCChambers1,11307132670
Sep 12, 2023Viper ChilekViper S.W.D., LLCMatagorda2,10032132459
Aug 10, 2023Clemens Salt DomeChevron Phillips Chemical Co LPBrazoria72203933377
Jun 27, 2023FeeOneok Hydrocarbon Southwest, LLCChambers82607132669

About this data

Formation tops, elevations, perforations, and casing from the RRC dbf900 wellbore file, refreshed weekly, with reported names normalized to Petrora's formation registry. County and operator breakdowns are rebuilt nightly.

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