The main subject of this paper is to discuss in detail the deltaic geologic model of the Rio Bonito Formation, already previously established, based only on studies of wire line log responses. The analysis of logs provided to separate five genetic sequences in the upper section of the Rio Tietê Série (Gama Jr. et al., 1982) represented by the Palermo, Rio Bonito and the top of the Itararé Formation. The research involved the Palermo and Itararé formations due to their close faciologic relationship in this sedimentary section. For each genetic sequence, a paleogeographic map was established, the stacking of which gives us the depositional evolution during the early Permian. Sequence I was deposited in a relative deep marine environment with glacial influences and the occurrence of turbiditic currents. The beginning of the deltaic system started within the top of this sequence, in the Rio Claro do Sui well area (RC-l-PR). Sequence II is characterized by deltaic progradation and consequent regression. The apex of the progradation occurred with sequence III which has coal and some limestones. During its deposition, the transgression came from the west and reworked the upper part of its sandstones, depositing marine bars with excellent reservoir characteristics, that constitutes sequence IV. The marine transgression deposited the Palermo Formation which is the youngest unit studied in this work. The present model fits to previously established concepts, like for instance, progradation coming from East-Northeast and the new geologic elements evidence the development of a delta inside the Palermo Formation with Northwest-Southeastward progradation.The main subject of this paper is to discuss in detail the deltaic geologic model of the Rio Bonito Formation, already previously established, based only on studies of wire line log responses. The analysis of logs provided to separate five genetic sequences in the upper section of the Rio Tietê Série (Gama Jr. et al., 1982) represented by the Palermo, Rio Bonito and the top of the Itararé Formation. The research involved the Palermo and Itararé formations due to their close faciologic relationship in this sedimentary section. For each genetic sequence, a paleogeographic map was established, the stacking of which gives us the depositional evolution during the early Permian. Sequence I was deposited in a relative deep marine environment with glacial influences and the occurrence of turbiditic currents. The beginning of the deltaic system started within the top of this sequence, in the Rio Claro do Sui well area (RC-l-PR). Sequence II is characterized by deltaic progradation and consequent regression. The apex of the progradation occurred with sequence III which has coal and some limestones. During its deposition, the transgression came from the west and reworked the upper part of its sandstones, depositing marine bars with excellent reservoir characteristics, that constitutes sequence IV. The marine transgression deposited the Palermo Formation which is the youngest unit studied in this work. The present model fits to previously established concepts, like for instance, progradation coming from East-Northeast and the new geologic elements evidence the development of a delta inside the Palermo Formation with Northwest-Southeastward progradation.