The code names YPF S.A., which operated the area when the well was drilled; Petrolera Pampa operates it today.
Spudded before Resolución SE 1040/2009: the code followed the earlier rules, from 1969.
A well code has up to six parts, separated by dots and a dash: the operator, the province, the field, the well type, the number and, in brackets, a characteristic.
| Code | Province | Wells in the register | Also written |
|---|---|---|---|
| SC | Santa Cruz | 22,392 | |
| Ch | Chubut | 19,455 | CH |
| Nq | Neuquén | 14,594 | NQ |
| Md | Mendoza | 4,954 | MD |
| RN | Río Negro | 4,380 | Rn |
| MdN | Mendoza, Neuquén Basin | 2,002 | |
| LP | La Pampa | 1,979 | |
| TF | Tierra del Fuego | 1,068 | |
| SCA | Santa Cruz, Austral Basin | 646 | |
| St | Salta | 376 | ST |
| Fr | Formosa | 51 | |
| Jj | Jujuy | 11 | |
| SJ | San Juan | 6 | |
| SL | San Luis | 5 | |
| BA | Buenos Aires | 3 | |
| ChCA | Chubut, Cañadón Asfalto Basin | 1 | |
| SCET | Santa Cruz, El Tranquilo Basin | 1 | |
| SF | Santa Fe | 1 |
| Letter | Type | What it is | Wells in the register |
|---|---|---|---|
| No letter | Development well | No letter: drilled inside the proven zone of a producing field. | |
| x | Exploration well | Looks for oil or gas in a trap not drilled before. | 3,694 |
| e | Extension well | Outlines the zone an exploration well discovered. | 643 |
| a | Step-out well | Drilled beyond the edge of the zone with proven hydrocarbons. | 5,839 |
| xp | Deep exploration well | Looks for hydrocarbons below a zone that already produces. | 239 |
| xs | Shallow exploration well | Tests a shallower level another well detected. | 7 |
| es | Study well | Studies the layers of a region with no other wells. | 76 |
| r | Re-entry well | A new well opened from another well's casing; it keeps that well's number. | 8 |
| p | Deepened well | The new, deeper section of an existing well; it keeps that well's number. | 10 |
| s | Disposal well | A service well that takes formation water or other fluids. | 86 |
| ia | Water injection well | Injects water to push the oil towards the producing wells. | 2,035 |
| ig | Gas injection well | Injects gas for secondary recovery. | 3 |
| iv | Steam injection well | Injects steam for secondary recovery. | 7 |
| it | Tertiary injection well | Injects polymers, gels or other tertiary recovery fluids. | 28 |
| c | Monitoring well | A service well for measuring pressures and taking samples. | 34 |
| Mark | Meaning | Detail |
|---|---|---|
| (h) | Horizontal | The well turns horizontal on its way to its target. |
| (d) | Directional | Deviated towards its target without turning horizontal. |
| (I), (II) | Replacement | Replaces a well of the same number abandoned for technical reasons. |
| (bis) | Replacement | A spelling from before 2009; the rules forbid it. |
The code names the company that operated the area when the well was drilled, not the one operating it today.
| Code | Company | Source | Wells in the register |
|---|---|---|---|
| YPF | YPF S.A. | Annex II | 43,245 |
| PAE | Pan American Energy LLC (Sucursal Argentina) | Annex II | 5,285 |
| AST | No published meaning | 1,671 | |
| AOC | No published meaning | 1,629 | |
| PC | No published meaning | 1,624 | |
| PBE | Petrobras Energía S.A. | Example in the rules | 1,385 |
| TPT | Tecpetrol S.A. | Annex II | 1,329 |
| CAP | Capex S.A. | Annex II | 1,327 |
| CFP | No published meaning | 1,267 | |
| PLU | Pluspetrol S.A. y Pluspetrol Energy S.A. | Annex II | 1,163 |
| SHE | No published meaning | 969 | |
| PAR | Petro Andina Resources Limited (Sucursal Argentina) | Annex II | 852 |
| AS | No published meaning | 809 | |
| PCR | Petroquímica Comodoro Rivadavia S.A. | Annex II | 799 |
| OXY | Occidental Argentina Exploration and Production Inc. | Annex II | 780 |
| CSJ | No published meaning | 760 | |
| PPC | No published meaning | 652 | |
| VOA | Vintage Oil Argentina | Register | 624 |
| PNR | Pioneer Natural Resources | Register | 548 |
| APS | No published meaning | 515 | |
| BRI | No published meaning | 451 | |
| PEL | Petrolera Entre Lomas S.A. | Annex II | 438 |
| SJ | No published meaning | 409 | |
| Pp | Pluspetrol | Register | 408 |
Unnamed codes are not in Annex II of the rules, and the register is not enough to attribute them to a company.
