Notice bibliographique
Résumé
Editor's column Chevron's decision last month to put its North American land-based natural gas drilling on hold highlights not only how tough things have become for drillers but also this year's divergence in oil and gas prices. Chevron cited poor demand and said it does not make sense to continue drilling and producing gas at depressed prices. Other operators and service companies also were pessimistic about the outlook for gas drilling for the rest of this year when announcing second quarter earnings. Gas prices in the US are at about a fourth of their value compared with a year ago. Oil prices have rebounded to half of their highs from last year, but the gas market finds itself hampered by new competing supplies from unconventionals, pipeline constraints, and built-in barriers to trade that oil does not face. In addition to poor demand caused by the recession, drillers are a victim of their own success. The growth of new unconventional gas-shale resources has created a significant oversupply that has helped beat down gas prices. Shale development has become prolific—at Barnett in Texas, Haynesville in Louisiana, and Marcellus in Pennsylvania, among others. Unconventional gas supplies seem to be gradually displacing conventional gas production in the US, a pattern that could be repeated in many parts of the world. Recently, energy companies in Europe have begun to turn more to unconventionals in light of maturing gas fields and concerns of dependence on Russian gas supplies. Finding and development costs for unconventional production have fallen, and technology advancements have greatly improved unconventional development prospects. Unconventional gas production has been growing sharply since 1990, even as conventional offshore and onshore gas output has declined. In addition, last year's high gas prices led to stepped up drilling, efforts paying off this year in increased production. Gas is not as tradable or as "moveable" as oil, which is part of the reason efforts to form a global gas cartel, similar to OPEC, have not gotten far. In the US, there is often a disconnect among new gas supplies, gas demand centers, and pipeline infrastructure or capacity. That makes gas prices regionalized, unlike oil, which limits trade that would naturally follow supply and demand signals. The increasing efficiency in gas-shale development and the exciting new prospects have encouraged some operators to continue drilling this year, including Chesapeake Energy and Anadarko. Early results from the Marcellus-shale development—it is estimated to contain 3 billion to 6 billion cubic feet of recoverable gas—have led Anadarko to believe that it could be a star in its onshore portfolio. The short-term outlook for gas prices is not good, despite what oil prices do. Gas-shale producers are likely to keep drilling. And new liquefied natural gas imports, not to mention new promising Canadian production such as Horn River, should only add pressure on gas.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,004 | 0,036 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,001 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,001 | 0,001 |
| Études des sciences et des technologies | 0,005 | 0,003 |
| Communication savante | 0,006 | 0,005 |
| Science ouverte | 0,002 | 0,002 |
| Intégrité de la recherche | 0,030 | 0,032 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,028 | 0,014 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».