MARK & SANDRA UNIT
Operated by ATLAS OPERATING LLC (P-5 36587) in the BRISCOE RANCH (EAGLEFORD) field. Every figure below is a volume the Railroad Commission published, multiplied by a monthly price you can check.
The Railroad Commission's own record for the field this lease produces from, including the spacing rule that governs how close together its wells may be drilled.
These are facts about the field, not about this lease. The field holds 5,584 leases and 8,017 wells, and the rule below applies to all of them.
A drilling unit in this field needs at least 40 acres. The field rule took effect on 2013-04-09.
The register flags this field for hydrogen sulphide. That is a poisonous gas that occurs naturally in some formations. The flag is a property of the field as the Commission records it. It is not a measurement taken at this lease, and it is not a statement that gas is escaping anywhere.
The Commission's schedule remark for this field reads: “MAY ELECT TO CLASSIFY AS PERMANENT GAS WELL”
What this lease produced, and what it was worth
Oil and condensate are valued on the volume the state records as disposed of; gas and casinghead gas on the volume produced. They are different columns of different files, and the difference is not cosmetic.
| Stream | Basis | Volume | Value |
|---|---|---|---|
| Oil | Disposition | 272,442 bbl | $20,450,228 |
| Casinghead gas | Production | 64,033 Mcf | $236,697 |
| Total | $20,686,925 | ||
Wells on this lease (2)
Every wellbore the Railroad Commission records against this lease key, with the depth, the last completion and the plug date exactly as filed. A well with no plug date is not stated to be producing — the state files no such flag.
These wells centre on 28.7048, -99.9289. A lease has no coordinate of its own — that point is the mean of its wells, and they span 1.0 miles.
What these wells add up to
Every figure below is counted over all of this lease's wells, not over the rows listed above. The Railroad Commission files two facts about a well's state — a plug date and a proration-schedule flag — and a well can carry both, so they are published as separate counts and never merged into a status.
What the state filed about each well
A plug date is the date the Commission recorded the wellbore as sealed with cement and abandoned. It is the only end-of-life fact Texas files. There is no "active" flag on a well, so this page does not print one — a well with no plug date is not stated to be producing.
How deep they were drilled
Between 5,843 and 5,896 ft, median 5,870 ft, over the 2 wells that filed a depth.
2 wells
| 42-50732943 | 3H | 5,843 ft | Dec 2012 | — | — |
| 42-50732900 | 2H | 5,896 ft | Jul 2012 | — | — |
The API number is the state's, prefixed 42 for Texas. A well is matched to this lease by the lease key the Commission files on the wellbore record, so a well that has moved between leases appears under each one it was filed against.
Every month this lease reported (168)
Volume × price = value, one row per cycle. The price columns are the same series published on the prices page — nothing here is modelled.
168 months
| May 2026 | 437 | 0 | 106.41 | 3.05 | $46,501 |
| Apr 2026 | 761 | 0 | 98.93 | 2.87 | $75,286 |
| Mar 2026 | 173 | 0 | 89.75 | 3.15 | $15,527 |
| Feb 2026 | 481 | 0 | 63.50 | 3.75 | $30,544 |
| Jan 2026 | 318 | 0 | 59.13 | 8.00 | $18,803 |
| Dec 2025 | 178 | 0 | 56.66 | 4.41 | $10,085 |
| Nov 2025 | 343 | 0 | 58.59 | 3.93 | $20,096 |
| Oct 2025 | 287 | 0 | 59.38 | 3.30 | $17,042 |
| Sep 2025 | 563 | 0 | 62.74 | 3.08 | $35,323 |
| Aug 2025 | 440 | 0 | 63.93 | 3.01 | $28,129 |
| Jul 2025 | 253 | 0 | 66.74 | 3.32 | $16,885 |
| Jun 2025 | 484 | 0 | 66.48 | 3.13 | $32,176 |
| May 2025 | 536 | 0 | 60.55 | 3.23 | $32,455 |
| Apr 2025 | 632 | 0 | 62.36 | 3.54 | $39,412 |
| Mar 2025 | 633 | 0 | 67.70 | 4.27 | $42,854 |
| Feb 2025 | 623 | 0 | 70.88 | 4.34 | $44,158 |
| Jan 2025 | 756 | 0 | 74.32 | 4.28 | $56,186 |
| Dec 2024 | 564 | 0 | 68.99 | 3.12 | $38,910 |
| Nov 2024 | 675 | 0 | 69.05 | 2.20 | $46,609 |
| Oct 2024 | 662 | 0 | 71.37 | 2.28 | $47,247 |
| Sep 2024 | 664 | 0 | 69.61 | 2.36 | $46,221 |
| Aug 2024 | 500 | 0 | 75.63 | 2.06 | $37,815 |
| Jul 2024 | 746 | 0 | 79.93 | 2.15 | $59,628 |
| Jun 2024 | 614 | 0 | 78.08 | 2.63 | $47,941 |
| May 2024 | 648 | 0 | 78.81 | 2.20 | $51,069 |
| Apr 2024 | 830 | 0 | 84.45 | 1.66 | $70,094 |
| Mar 2024 | 655 | 0 | 80.30 | 1.55 | $52,597 |
| Feb 2024 | 659 | 0 | 76.09 | 1.78 | $50,143 |
| Jan 2024 | 325 | 0 | 73.02 | 3.30 | $23,732 |
| Dec 2023 | 670 | 0 | 71.26 | 2.61 | $47,744 |
| Nov 2023 | 1,050 | 0 | 77.89 | 2.81 | $81,785 |
| Oct 2023 | 822 | 0 | 85.44 | 3.09 | $70,232 |
| Sep 2023 | 506 | 0 | 89.04 | 2.74 | $45,054 |
| Aug 2023 | 662 | 0 | 80.52 | 2.67 | $53,304 |
| Jul 2023 | 664 | 0 | 74.85 | 2.64 | $49,700 |
| Jun 2023 | 509 | 0 | 68.96 | 2.26 | $35,101 |
| May 2023 | 669 | 0 | 70.62 | 2.23 | $47,245 |
| Apr 2023 | 348 | 0 | 78.12 | 2.24 | $27,186 |
| Mar 2023 | 679 | 0 | 72.85 | 2.39 | $49,465 |
| Feb 2023 | 181 | 0 | 75.11 | 2.47 | $13,595 |
| Jan 2023 | 691 | 0 | 76.53 | 3.39 | $52,882 |
| Dec 2022 | 720 | 0 | 76.41 | 5.73 | $55,015 |
| Nov 2022 | 515 | 0 | 85.00 | 5.65 | $43,775 |
| Oct 2022 | 836 | 0 | 87.18 | 5.86 | $72,882 |
| Sep 2022 | 475 | 0 | 84.88 | 8.16 | $40,318 |
| Aug 2022 | 515 | 0 | 94.52 | 9.13 | $48,678 |
| Jul 2022 | 849 | 0 | 101.58 | 7.54 | $86,241 |
| Jun 2022 | 689 | 0 | 115.09 | 7.98 | $79,297 |
| May 2022 | 634 | 0 | 109.37 | 8.43 | $69,341 |
| Apr 2022 | 990 | 0 | 104.22 | 6.84 | $103,178 |
| Mar 2022 | 675 | 0 | 108.88 | 5.08 | $73,494 |
| Feb 2022 | 688 | 0 | 91.05 | 4.86 | $62,642 |
| Jan 2022 | 854 | 0 | 81.84 | 4.54 | $69,891 |
| Dec 2021 | 874 | 0 | 71.32 | 3.90 | $62,334 |
| Nov 2021 | 707 | 0 | 77.43 | 5.24 | $54,743 |
| Oct 2021 | 699 | 0 | 79.79 | 5.71 | $55,773 |
| Sep 2021 | 848 | 0 | 69.86 | 5.35 | $59,241 |
| Aug 2021 | 989 | 0 | 66.02 | 4.22 | $65,294 |
| Jul 2021 | 864 | 0 | 70.78 | 3.98 | $61,154 |
| Jun 2021 | 849 | 0 | 69.49 | 3.38 | $58,997 |
| May 2021 | 881 | 0 | 63.48 | 3.02 | $55,926 |
| Apr 2021 | 813 | 0 | 60.36 | 2.76 | $49,073 |
| Mar 2021 | 972 | 0 | 61.30 | 2.72 | $59,584 |
| Feb 2021 | 657 | 0 | 57.80 | 5.55 | $37,975 |
| Jan 2021 | 1,121 | 0 | 50.41 | 2.81 | $56,510 |
| Dec 2020 | 978 | 0 | 44.64 | 2.68 | $43,658 |
| Nov 2020 | 648 | 0 | 38.77 | 2.71 | $25,123 |
| Oct 2020 | 969 | 0 | 36.97 | 2.48 | $35,824 |
| Sep 2020 | 1,133 | 0 | 37.09 | 1.99 | $42,023 |
| Aug 2020 | 797 | 9 | 39.98 | 2.39 | $31,886 |
| Jul 2020 | 1,139 | 0 | 38.37 | 1.83 | $43,703 |
| Jun 2020 | 643 | 0 | 34.90 | 1.69 | $22,441 |
| May 2020 | 1,129 | 0 | 16.92 | 1.81 | $19,103 |
| Apr 2020 | 664 | 0 | 14.75 | 1.80 | $9,794 |
| Mar 2020 | 1,161 | 5 | 30.34 | 1.86 | $35,234 |
| Feb 2020 | 969 | 105 | 49.88 | 1.98 | $48,542 |
| Jan 2020 | 1,173 | 62 | 57.25 | 2.09 | $67,284 |
| Dec 2019 | 806 | 58 | 59.01 | 2.30 | $47,696 |
| Nov 2019 | 988 | 60 | 55.30 | 2.75 | $54,801 |
| Oct 2019 | 1,001 | 126 | 53.47 | 2.42 | $53,828 |
| Sep 2019 | 881 | 179 | 55.05 | 2.66 | $48,975 |
| Aug 2019 | 1,022 | 102 | 53.11 | 2.30 | $54,513 |
| Jul 2019 | 856 | 62 | 56.27 | 2.46 | $48,320 |
| Jun 2019 | 1,032 | 60 | 52.78 | 2.49 | $54,618 |
| May 2019 | 1,101 | 124 | 58.48 | 2.74 | $64,726 |
| Apr 2019 | 979 | 126 | 62.63 | 2.75 | $61,661 |
| Mar 2019 | 1,189 | 86 | 56.80 | 3.06 | $67,799 |
| Feb 2019 | 1,005 | 54 | 50.85 | 2.79 | $51,255 |
| Jan 2019 | 1,044 | 79 | 46.03 | 3.23 | $48,310 |
| Dec 2018 | 900 | 22 | 46.59 | 4.19 | $42,023 |
| Nov 2018 | 874 | 60 | 52.93 | 4.24 | $46,515 |
| Oct 2018 | 1,262 | 95 | 61.44 | 3.40 | $77,860 |
| Sep 2018 | 1,055 | 94 | 59.54 | 3.11 | $63,107 |
| Aug 2018 | 1,046 | 117 | 59.40 | 3.07 | $62,491 |
| Jul 2018 | 1,200 | 132 | 65.14 | 2.93 | $78,555 |
| Jun 2018 | 1,170 | 102 | 60.18 | 3.08 | $70,724 |
| May 2018 | 1,120 | 99 | 65.38 | 2.90 | $73,513 |
| Apr 2018 | 1,020 | 90 | 63.84 | 2.90 | $65,378 |
| Mar 2018 | 1,083 | 88 | 61.22 | 2.79 | $66,547 |
| Feb 2018 | 891 | 70 | 61.78 | 2.77 | $55,240 |
| Jan 2018 | 1,071 | 79 | 62.87 | 4.01 | $67,651 |
| Dec 2017 | 1,226 | 68 | 57.27 | 2.92 | $70,412 |
| Nov 2017 | 1,056 | 75 | 55.42 | 3.12 | $58,757 |
| Oct 2017 | 1,256 | 74 | 49.29 | 2.98 | $62,129 |
| Sep 2017 | 1,047 | 49 | 47.52 | 3.09 | $49,905 |
| Aug 2017 | 1,019 | 68 | 45.37 | 3.00 | $46,436 |
| Jul 2017 | 1,042 | 90 | 43.87 | 3.09 | $45,990 |
| Jun 2017 | 1,200 | 112 | 42.49 | 3.09 | $51,334 |
| May 2017 | 997 | 82 | 45.37 | 3.26 | $45,501 |
| Apr 2017 | 1,367 | 115 | 47.93 | 3.21 | $65,890 |
| Mar 2017 | 1,189 | 128 | 46.77 | 2.98 | $55,991 |
| Feb 2017 | 1,006 | 116 | 50.45 | 2.95 | $51,095 |
| Jan 2017 | 1,190 | 133 | 49.41 | 3.42 | $59,253 |
| Dec 2016 | 1,242 | 208 | 48.76 | 3.72 | $61,334 |
| Nov 2016 | 1,159 | 148 | 42.49 | 2.64 | $49,637 |
| Oct 2016 | 1,239 | 154 | 46.19 | 3.09 | $57,705 |
| Sep 2016 | 1,020 | 149 | 41.55 | 3.10 | $42,843 |
| Aug 2016 | 1,418 | 154 | 41.44 | 2.92 | $59,212 |
| Jul 2016 | 879 | 208 | 41.62 | 2.92 | $37,192 |
| Jun 2016 | 1,416 | 233 | 45.35 | 2.69 | $64,841 |
| May 2016 | 871 | 65 | 42.52 | 1.99 | $37,164 |
| Apr 2016 | 1,058 | 36 | 36.56 | 1.99 | $38,752 |
| Mar 2016 | 860 | 38 | 33.01 | 1.79 | $28,457 |
| Feb 2016 | 1,342 | 174 | 26.47 | 2.06 | $35,882 |
| Jan 2016 | 2,014 | 210 | 27.35 | 2.36 | $55,579 |
| Dec 2015 | 1,719 | 203 | 32.36 | 2.00 | $56,033 |
| Nov 2015 | 2,315 | 218 | 38.79 | 2.17 | $90,271 |
| Oct 2015 | 1,850 | 278 | 43.55 | 2.43 | $81,242 |
| Sep 2015 | 1,655 | 336 | 42.99 | 2.76 | $72,075 |
| Aug 2015 | 2,004 | 325 | 40.16 | 2.87 | $81,414 |
| Jul 2015 | 2,039 | 335 | 48.15 | 2.95 | $99,164 |
| Jun 2015 | 2,044 | 309 | 56.15 | 2.88 | $115,661 |
| May 2015 | 2,320 | 289 | 55.21 | 2.96 | $128,941 |
| Apr 2015 | 1,799 | 287 | 49.82 | 2.71 | $90,403 |
| Mar 2015 | 2,285 | 304 | 42.89 | 2.93 | $98,896 |
| Feb 2015 | 2,267 | 262 | 44.66 | 2.98 | $102,024 |
| Jan 2015 | 1,890 | 1,249 | 43.43 | 3.10 | $85,955 |
| Dec 2014 | 2,624 | 2,115 | 54.69 | 3.59 | $151,102 |
| Nov 2014 | 2,631 | 2,007 | 70.46 | 4.25 | $193,914 |
| Oct 2014 | 2,827 | 2,012 | 78.30 | 3.90 | $229,203 |
| Sep 2014 | 2,433 | 1,911 | 86.16 | 4.05 | $217,358 |
| Aug 2014 | 2,823 | 1,886 | 89.39 | 4.04 | $259,958 |
| Jul 2014 | 3,140 | 1,745 | 96.56 | 4.18 | $310,492 |
| Jun 2014 | 3,161 | 1,534 | 98.16 | 4.74 | $317,550 |
| May 2014 | 2,988 | 1,242 | 94.73 | 4.73 | $288,924 |
| Apr 2014 | 3,184 | 756 | 95.94 | 4.81 | $309,109 |
| Mar 2014 | 3,359 | 697 | 95.89 | 5.06 | $325,619 |
| Feb 2014 | 3,206 | 568 | 97.40 | 6.19 | $315,781 |
| Jan 2014 | 3,624 | 711 | 90.40 | 4.86 | $331,066 |
| Dec 2013 | 3,245 | 1,239 | 91.82 | 4.35 | $303,351 |
| Nov 2013 | 3,873 | 1,239 | 88.85 | 3.74 | $348,748 |
| Oct 2013 | 4,056 | 1,890 | 97.42 | 3.78 | $402,279 |
| Sep 2013 | 4,020 | 1,909 | 104.11 | 3.72 | $425,619 |
| Aug 2013 | 4,614 | 2,136 | 104.25 | 3.52 | $488,534 |
| Jul 2013 | 4,682 | 2,166 | 102.52 | 3.72 | $488,051 |
| Jun 2013 | 5,106 | 2,332 | 94.40 | 3.93 | $491,179 |
| May 2013 | 5,736 | 1,483 | 94.83 | 4.15 | $550,098 |
| Apr 2013 | 6,312 | 3,165 | 93.96 | 4.28 | $606,630 |
| Mar 2013 | 8,692 | 3,719 | 93.62 | 3.91 | $828,297 |
| Feb 2013 | 8,089 | 2,160 | 91.23 | 3.42 | $745,346 |
| Jan 2013 | 10,516 | 2,979 | 91.60 | 3.42 | $973,454 |
| Dec 2012 | 5,581 | 1,850 | 86.77 | 3.42 | $490,591 |
| Nov 2012 | 4,140 | 1,359 | 86.95 | 3.62 | $364,899 |
| Oct 2012 | 5,952 | 1,811 | 89.38 | 3.40 | $538,147 |
| Sep 2012 | 5,557 | 1,550 | 94.67 | 2.92 | $530,605 |
| Aug 2012 | 11,017 | 2,275 | 92.66 | 2.91 | $1,027,451 |
| Jul 2012 | 5,349 | 1,960 | 85.13 | 3.02 | $461,281 |
| Jun 2012 | 1 | 0 | 79.82 | 2.52 | $80 |
How to read this page
The arithmetic is one multiplication per stream per month. Here it is, worked, on a real row from the table above.
Oil 437 bbl × $106.41 = $46,501 Casinghead gas 0 Mcf × $ 3.05 = $0 ──────────────────────────────────────────────────── Month total $46,501
The volumes are the state's, unchanged
Every barrel and every Mcf on this page is a number the Railroad Commission of Texas published in its monthly production query. Nothing is modelled, estimated or filled in.
The dollars are a multiplication, not a valuation
Volume × a published monthly price. It is not what the operator was paid: it takes no account of a contract, a differential, a transportation deduction, or the share any one owner holds.
Oil and gas are priced differently
Oil is a Texas realisation — the crude oil first purchase price. Gas is a benchmark, because no free Texas wellhead gas series exists at any date. The prices page publishes the difference rather than correcting it away.
A lease is not a well
The state reports oil on lease and gas on well, and this page is the lease grain. 01/O/16060 is the state's own key, not one this site invented.