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v3.24.3

Supplementary Information for Exploration and Production Activities - Proved Developed and Undeveloped Oil and Gas Reserve Quantities (Details) Bcf in Thousands | 12 Months Ended |
--- | --- | ---
Sep. 30, 2024 MBbls MMcf Bcf | Sep. 30, 2023 MMcf MBbls Bcf | Sep. 30, 2022 MBbls MMcf Bcf | Sep. 30, 2021 MMcf MBbls
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved undeveloped reserve volume | Bcf |  | 1,267,000,000 | 985,000,000 | 858,000,000 |
Gas MMcf |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved Developed and Undeveloped Reserves, Beginning of Period |  | 4,535,084 | 4,170,662 | 3,723,433 |
Extensions and Discoveries |  | 601,679 | 670,438 | 837,510 |
Revisions of Previous Estimates |  | 7,046 | 32,379 | 2,953 |
Production |  | (392,047) | (372,271) | (342,911) |
Sale of Minerals in Place |  |  |  | (50,323) |
Purchases of Minerals in Place |  |  | 33,876 |  |
Proved Developed and Undeveloped Reserves, End of Period |  | 4,751,762 | 4,535,084 | 4,170,662 |
Proved developed reserves volume |  | 3,484,852 | 3,550,034 | 3,312,568 | 3,091,463
Proved undeveloped reserve volume |  | 1,266,910 | 985,050 | 858,094 | 631,970
Oil Mbbl |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved Developed and Undeveloped Reserves, Beginning of Period | MBbls |  | 216 | 250 | 21,537 |
Extensions and Discoveries | MBbls |  |  |  | 296 |
Revisions of Previous Estimates | MBbls |  | 8 | (4) | 787 |
Production |  | (31) | (30) | (1,604) |
Sale of Minerals in Place | MBbls |  |  |  | (20,766) |
Proved Developed and Undeveloped Reserves, End of Period | MBbls |  | 193 | 216 | 250 |
Proved developed reserves volume | MBbls |  | 193 | 216 | 250 | 20,941
Proved undeveloped reserve volume | MBbls |  | 0 | 0 | 0 | 596
Appalachian Region | Gas MMcf |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved Developed and Undeveloped Reserves, Beginning of Period |  | 4,535,084 | 4,170,662 | 3,693,148 |
Extensions and Discoveries | [1] | 601,679 | 670,438 | 837,510 |
Revisions of Previous Estimates |  | 7,046 | 32,379 | 2,882 |
Production | [2] | (392,047) | (372,271) | (341,700) |
Sale of Minerals in Place |  |  |  | (21,178) |
Purchases of Minerals in Place |  |  | 33,876 |  |
Proved Developed and Undeveloped Reserves, End of Period |  | 4,751,762 | 4,535,084 | 4,170,662 |
Proved developed reserves volume |  | 3,484,852 | 3,550,034 | 3,312,568 | 3,061,178
Proved undeveloped reserve volume |  | 1,266,910 | 985,050 | 858,094 | 631,970
Appalachian Region | Oil Mbbl |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved Developed and Undeveloped Reserves, Beginning of Period | MBbls |  | 216 | 250 | 11 |
Extensions and Discoveries | MBbls |  |  |  | 0 |
Revisions of Previous Estimates | MBbls |  | 8 | (4) | 255 |
Production |  | (31) | (30) | (16) |
Sale of Minerals in Place | MBbls |  |  |  | 0 |
Proved Developed and Undeveloped Reserves, End of Period | MBbls |  | 193 | 216 | 250 |
Proved developed reserves volume | MBbls |  | 193 | 216 | 250 | 11
Proved undeveloped reserve volume | MBbls |  | 0 | 0 | 0 | 0
West Coast Region | Gas MMcf |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved Developed and Undeveloped Reserves, Beginning of Period |  | 0 | 0 | 30,285 |
Extensions and Discoveries |  | 0 | 0 | 0 |
Revisions of Previous Estimates |  | 0 | 0 | 71 |
Production |  | 0 | 0 | (1,211) |
Sale of Minerals in Place |  |  |  | (29,145) |
Purchases of Minerals in Place |  |  | 0 |  |
Proved Developed and Undeveloped Reserves, End of Period |  | 0 | 0 | 0 |
Proved developed reserves volume |  | 0 | 0 | 0 | 30,285
Proved undeveloped reserve volume |  | 0 | 0 | 0 | 0
West Coast Region | Oil Mbbl |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved Developed and Undeveloped Reserves, Beginning of Period | MBbls |  | 0 | 0 | 21,526 |
Extensions and Discoveries | MBbls |  |  |  | 296 |
Revisions of Previous Estimates | MBbls |  | 0 | 0 | 532 |
Production |  | 0 | 0 | (1,588) |
Sale of Minerals in Place | MBbls |  |  |  | (20,766) |
Proved Developed and Undeveloped Reserves, End of Period | MBbls |  | 0 | 0 | 0 |
Proved developed reserves volume | MBbls |  | 0 | 0 | 0 | 20,930
Proved undeveloped reserve volume | MBbls |  | 0 | 0 | 0 | 596
Marcellus Shale Fields |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved undeveloped reserve volume | Bcf |  | 342,000,000 | 112,000,000 | 355,000,000 |
Marcellus Shale Fields | Gas MMcf |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Extensions and Discoveries | Bcf |  | 230 | 163 | 301 |
Production |  | (235,955) | (190,290) | (209,463) |
Percentage exceeding total reserve of production in proved developed and undeveloped reserves |  | 15.00% |  |  |
Utica Shale |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Proved undeveloped reserve volume | Bcf |  | 925,000,000 | 873,000,000 | 503,000,000 |
Utica Shale | Gas MMcf |  |  |  |  |
Proved Developed and Undeveloped Reserves [Roll Forward] |  |  |  |  |
Extensions and Discoveries | Bcf |  | 372 | 507 | 537 |
Production |  | (154,701) | (180,750) | (130,240) |
Percentage exceeding total reserve of production in proved developed and undeveloped reserves |  | 15.00% |  |  |
[1] | Extensions and discoveries include 301 Bcf (during 2022), 163 Bcf (during 2023) and 230 Bcf (during 2024), of Marcellus Shale gas (which exceed 15% of total reserves) in the Appalachian region. Extensions and discoveries include 537 Bcf (during 2022), 507 Bcf (during 2023) and 372 Bcf (during 2024), of Utica Shale gas (which exceed 15% of total reserves) in the Appalachian region.
[2] | Production includes 209,463 MMcf (during 2022), 190,290 MMcf (during 2023) and 235,955 MMcf (during 2024), from Marcellus Shale fields. Production includes 130,240 MMcf (during 2022), 180,750 MMcf (during 2023) and 154,701 MMcf (during 2024), from Utica Shale fields.

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- Definition Additions to proved reserves that result from (1) extension of the proved acreage of previously discovered (old) reservoirs through additional drilling in periods after discovery and (2) discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Form 20-F -Number Part II -Section Item 18 -Subparagraph (Instruction 2) -Publisher SEC Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 55 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477916/932-235-55-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-8 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-3 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-8 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-5 + Details
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- Definition The net quantity of proved reserves as of the balance sheet date. Proved oil reserves are the estimated quantities of crude oil and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Form 20-F -Number Part II -Section Item 18 -Subparagraph (Instruction 2) -Publisher SEC Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 55 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477916/932-235-55-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-8 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-3 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-8 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 932 -SubTopic 235 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477215/932-235-50-4 + Details
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