Banca de QUALIFICAÇÃO: ANDERSON HENRIQUE DE MELO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ANDERSON HENRIQUE DE MELO
DATE: 18/05/2021
TIME: 09:00
LOCAL: Videoconferencia -
TITLE:

STRATIGRAPHIC ANALYSIS FROM THE ALBIAN TO CAMPANIAN STAGE  OF THE POTIGUAR BASIN: FROM SEISMIC TO RESERVOIR SCALE

KEY WORDS:

Potiguar Basin; Sequence Stratigraphy; High-resolution Sequence Stratigraphy; Reservoir Management

PAGES: 146
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUMMARY:

A stratigraphic analysis integrating seismic, well data and biostratigraphic data led to  the definition of five third-order depositional sequences and their respective system tracts between the Albian and Campanian stages of the Potiguar Basin. As they  become younger, the falling stage and lowstand system tracts of depositional  sequences become thinner or are not interpreted, and transgressive and highstand  system tracts become thicker, which reflects the general transgressive trend of the  second order sequence in which they are inserted. The Depositional Sequence 1  comprises Albian siliciclastic and carbonate deposits. The Falling Stage System Tract  of Depositional Sequence 1 (FSST 1) is preserved in submarine canyon C1. The  Lowstand System Tract of Depositional Sequence 1 (LST 1) is composed of fluvial deposits restricted to valleys or non-confined and amalgamated and deltaic deposits basinward. Marine carbonate rocks (Ponta do Mel Formation) and their onshore fluvial  counterparts represent the Transgressive (TST 1) and Highstand (HST 1) system  tracts. Depositional Sequence 2 are mid- to early Cenomanian aged. The submarine  canyon C2 is filled with FSST 2 and LST 2. Onshore, LST 2 is composed of braided fluvial systems. TST 2 onlaps the Maximum Regression Surface (MRS 2) in the marine  section and is composed of meandering and tide influenced fluvial deposits onshore. The HST 2 downlaps the Maximum Flood Surface 2 (MFS 2) and is very restricted  onshore. Depositional Sequence 3 is late Cenomanian to mid-Turonian aged. TST 3  onlaps MRS 3 in the marine sections and is composed of meandering fluvial and  estuarine deposits onshore. HST 3 downlaps MFS 3 in the marine section and is  composed of carbonate deposits and their onshore siliciclastic counterparts. The  depositional sequences 4 and 5 are entirely inserted within the context of the  carbonate platform of the Jandaíra Formation and only transgressive and highstand  system tracts were interpreted. Açu Formation, the main oil-bearing formation of the  Potiguar Basin, is inserted into depositional sequences 1, 2 and 3 and is strongly  affected by the lateral and vertical variations of the depositional systems. The  stratigraphic framework defined on a seismic scale is a starting point for the  stratigraphic refinement on a reservoir scale. From the integrated analysis of rock data,  electric logs and production data of a mature heavy oil field, part of the fluvial section of TST 2 (inserted in the Açu Formation) was subdivided into 9 fourth-order  depositional sequences. The subaerial unconformities that limit them are interpreted at  the top of paleosol levels that are correlated throughout the study area and that control  the fluid flow within reservoirs. The nine high-frequency depositional sequences of TST  2 and the LST 2 now represent the reservoir zonation of the studied interval, replacing  the four previous lithostratigraphic zones. The new reservoir zonation allowed a more  detailed reservoir characterization and led to a better representation of fluvial systems  in 3D geological models and to the correction of mapping errors. The understanding of  the fluid flow pattern within the reservoirs led to the closing of intervals that are harmful  to production, as well as to the identification of remaining oil not produced, responsible  for increasing the useful life of wells submitted to cyclic steam stimulation. Such results  reinforce the importance of high-resolution sequence stratigraphy as a tool for the  improvement of mature fields recovery factors. The same methodology was used for  the stratigraphic refinement of part of the HST 1 carbonate platform (inserted in the  Ponta do Mel Formation), where four fourth-order genetic sequences were interpreted.  Although this interval does not contain hydrocarbons, the proposed stratigraphic  framework is useful as an analogy for the study and description of stratigraphic  heterogeneities in marine carbonate reservoirs. Such results can be replicated in other areas and stratigraphic intervals of the Potiguar Basin and in other basins, being able  to contribute to the oil industry both on an exploratory and reservoir scale 

BANKING MEMBERS:
Externo à Instituição - GUILHERME PEDERNEIRAS RAJA GABAGLIA - PETROBRAS
Externo à Instituição - CLAITON MARLON DOS SANTOS SCHERER - UFRGS
Presidente - 1161652 - FRANCISCO PINHEIRO LIMA FILHO