The present project generated a substantial amount of geological, geochemical, geophysical data interpretations in the study area with the objective of making an identification of oil and gas shales plays. The study area is the Camaçari Low which is the deepest depocenter of the Recôncavo Basin, an extremely faulted and complex asymmetric graben. The sedimentation of reservoir rocks was controlled by the tectonic framework of the graben, shale diapirism and listric faults.

A large set of geochemical data was used to characterize the traditional source rocks of the basin, Gomo and Tauá members. The geochemical characterization was able to describe the distribution of rich organic intervals in depth and across the studied area. A compilation of rock-eval analyses from many wells of the area was useful to define the top of oil generation peak based on the variation of HI and TOC of the Candeias Fm rocks and on the increase of Tmax and PI (production index) with depth. Using the impressive amount of geochemistry on source rocks data and the stratigraphical framework built in this project, the amount of petroleum generated was computed with a 3D basin modeling that yielded a useful map showing the distribution of the accumulated bulk mass of petroleum generated in the area.

Full references of all images are listed in the reports

1. Introduction
   1. Location of the Study Area
   2. Objectives and Main Tasks
   3. Geological and Geophysical Data
   4. Oil and Gas Reserves
2. Geology of the Recôncavo Basin
   1. Tectonic and stratigraphic general considerations
   2. Main Faults and Fractures
   3. Geochemistry
      1. Geochemical Database
      2. Oil Characteristics
      3. Source rocks and Organic Richness
      4. TOC Maps
      5. Hidrogen Index Maps
      6. Maturity and Transformation Ratio of the Source Rocks
      7. Rock-Eval – Tmax
   4. Petroleum Model – Migration Models in the Recôncavo Basin
      1. Seals
      2. Bulk Migration
   5. Macro Facies Interpretation (Sandstone/Shale Ratio Maps)
   6. Suite of Regional Cross Sections
   7. Porosity Estimated from Logs
   8. Play Types
      1. Conventional Plays
      2. Unconventional, Near Conventional Plays
   9. Hydrocarbon Shows Maps
3. Seismic interpretation
   1. Seismic-Based Structural Maps (in Time)
   2. Quality Check of the Depth Conversion
   3. Seismic-Based Structural Maps (in Depth)
4. Estimates of Hydrocarbon Volumes
5. Marginal Fields Introduction
6. Marginal Fields Geological Description
   1. Jacuipe Field – A model for the sedimentary processes in the study area
   2. Dias D’Ávila Marginal Field
   3. Camaçari and Bom Viver Marginal Fields
   4. Mapele and Aratu Marginal Fields
      1. Summary of the Tests in the Mapele Area
      2. Summary of Tests in the Aratu Area
      3. Seismic View of the Mapele Marginal Field
   5. Cinzento Marginal Field
      1. Summary of the 1CZ-2 well
      2. Well 1-CZ-3-BA (report summary)
      3. Cinzento Marginal Field Seismic View
   6. Cantagalo Marginal Field
   7. Marginal Fields Fazenda Sori (FS); Pedrinhas (PDR); Brejo Preto (BRP) and Fazenda Panelas (FAP)
      1. Fazenda Alto das Pedras (FAP) and Brejo Preto (BRP) Marginal FieldS
      2. Pedrinhas (PDR), Brejo Preto (BRP) and Fazenda Sori (FS) Marginal Fields
   8. Summary of the Marginal Petroleum Fields Production History and the Camaçari Low Exploration Potential
      1. Dias D’ávila Marginal Field
      2. Fazenda Alto das Pedras Margina Field (FAP)
      3. Pedrinhas Marginal Field (PDR)
      4. Fazenda Sori Marginal Field (FS)
      5. Cantagalo Marginal Field (CGL)
   9. Summary of the Petroleum Fields Characteristics
7. Conclusions and Recommendations
8. References

1. Location of the study area and the blocks that were offered in ANP Bid Round 10. The urban areas, as well as water reservoirs are also indicated.
2. Location of regional geological cross-sections interpreted for this study.
3. Map of the southern Recôncavo Basin showing an outline of the area of interest for this study. The black dots are exploratory wells of ANP and the blue dots are the wells in the database.
4. Map of the area of interest in the southern Recôncavo Basin showing the available seismic lines to be interpreted.
5. Recôncavo Basin stratigraphic chart. The chronostratigraphic and formation tops that concern this study are outlined.
6. Simplified tectonic map of top Sergi Fm. Only the main faults are shown (from Destro, 2002).
7. Geologic sections across the Mata Catu Fault South (a) and North (b). Note that section (a) crosses Água Grande Field and (b) Buracica Field (from Destro, 2002).
8. Detailed geologic map along the Mata Catu Fault zone. Note that the fault is segmented and that the north segment dips northeast whereas the other segments dip northwest (from Destro, 2002).
9. Block diagram showing the main faults and structural compartments of the basin (Destro, 2002). The two parts of the Mata Catu Fault are outlined by dark blue lines. The faulted area in the Candeias Field is outlined by a dark red line.
10. Location of the Candeias Field.
11. Structural map in the Candeias Field area at the level of Marco 3Z (third production zone of the field). Note how intensively faulted this area is (Destro, 2002), which might be one of the reasons of the productivity of the field.
12. Contour lines (in barrels) of losses of drilling fluid in the Candeias Field.
13. Cross section along the Candeias Field emphasizing the 4th zone, which is a producing zone in fractured shale.
14. Fault zones oriented NW and NE intersecting sandstones of São Sebastião Formation. The hammer is pointing to north. The picture was taken near the Mata de São João city (Destro, 2002).
15. Location of diapirs (green circles) in the contour map. Simplified from Carlotto (2006).
16. Thickness map of the Gomo Member. Note how thick the source rocks are in eastern side of the south compartment (Camaçari Low) (picture modified from Figueiredo et al., 1994).
17. Map with the location of two organically rich wells (1-STM-1-BA; 1-SS-3-BA) and two lean wells (6CA-10-BA; 1-MP-2-BA).
18. Natural series plot of all samples of Candeias Formation. The red dashed line indicates the top of oil generation zone (figure from HRT BrazilGeodata).
19. Well 1-DA-0001-BA. This figure illustrates the position of the Rio da Serra and Gomo/Tauá layers (on the right) for which the geochemical data were generated.
20. Present day TOC map of the slice: Gomo-Rio da Serra-1.
21. Present day TOC map of the slice: Gomo-Rio da Serra-2.
22. Present day TOC map of the slice: Gomo-Rio da Serra-3.
23. Present day TOC map of the slice: Gomo-Rio da Serra-4.
24. Present day TOC map of the slice: Gomo-Rio da Serra-5.
25. Present day TOC map of the slice: Tauá-Gomo-1.
26. Present day TOC map of the slice: Tauá-Gomo-2.
27. Present day HI map of the slice: Gomo/Rio da Serra-1.
28. Present day HI map of the slice:Gomo/Rio da Serra-2.
29. Present day HI map of the slice:Gomo/Rio da Serra-3.
30. Present day HI map of the slice:Gomo/Rio da Serra-4.
31. Present day HI map of the slice:Gomo/Rio da Serra-5.
32. Present day HI map of the slice: Tauá/Gomo-1.
33. Present day HI map of the slice: Tauá/Gomo-2.
34. Geochemical log of the Santa Maria well (1-STM-1-BA). This is a typical well log of a organically rich Candeias Fm in the study area (ANP). The interpreted top and bottom of Gomo Member are indicated by the horizontal black lines (figure from HRT BrazilGeodata).
35. Maturation map of the top Candeias Formation. The colored lines represent: top oil window (green, %Ro=0.6), peak oil generation (red, %Ro=0.9) and wet gas generation (in yellow; %Ro=1.2) (HRT Internal Report; simplified from Coutinho, 2008).
36. Depth map of base Candeias Formation with oil and gas generation zones indicated by the thick lines. The dark red line is the top of gas window (~4,300m) whereas the top oil window is indicated by the dark green line (~2,500m). (Maturation Evaluation of Recôncavo Basin. HRT Internal Report)
37. On the left: present day transformation ratio map of the upper part of Candeias Fm. On the right: restored TOC map of Recôncavo Basin (Coutinho, 2008).
38. E-W cross section of Reconcavo Basin illustrating the main play types and migration pathways (modified from Braga, 2004).
39. Migration model in the Camaçari Low along a SW-NE seismic section. Horizontal migration is controlled by the shales of Maracangalha Fm and by those of Gomo Member. Vertical migration takes place along normal faults (NE) and oblique ones (NW).
40. Sandstone/shale ratio map of the lower part of Aratu Stage (slice Rio da Serra/Aratu-2). Note that most of the area has 70% shale.
41. Structural map of top Aratu stage (in TWT). The composite log of 1-DA-1-BA well shows the amount of shales of Maracangalha Fm in the NE part of the study area.
42. Well correlation showing large number of oil and gas shows in the Rio da Serra Stage.
43. Well 1-DA-0001-BA. This well is an example to illustrate the horizons (on the right) that were mapped in the area. The intermediate layers are the slices that were obtained by an equal division of the layer thickness.
44. Sand/shale ratio map of the sub-layer Tauá-Gomo-2. Note that most of the map has low sandstone content.
45. Sand/shale ratio map of the sub-layer Tauá-Gomo-1. Note that only the green and yellow areas have sandstone content above 20%.
46. Sand/shale ratio map of the lowermost sub-layer of Rio da Serra layer (Gomo – Rio da Serra-5).
47. Sand/shale ratio map of the lowermost sub-layer of Rio da Serra layer (Gomo – Rio da Serra-4).
48. Sand/shale ratio map of the intermediate sub-layer of the Rio da Serra layer (Gomo-Rio da Serra-3).
49. Sand/shale ratio map of the sub-layer 2 of the Rio da Serra layer (Gomo-Rio da Serra-1) .
50. Sandstone/shale map of the lower part of Aratu layer (Rio da Serra-Aratu-2).
51. Sandstone/shale map of the upper part of Aratu layer (Rio da Serra-Aratu-1).
52. Red circles represent average log porosity estimated only where sandstones exist within the Jiquiá layer.For illustration purposes, the structural map (in meters) of top Jiquiá is presented in the background.
53. Red circles represent average log porosity estimated only where sandstones exist within the Buracica layer. For illustration purposes, the structural map of top Buracica is presented in the background.
54. Red circles represent average log porosity estimated only where sandstones exist within the Aratu layer. For illustration purposes, the structural map of top Aratu is presented in the background.
55. Red circles represent average log porosity estimated only where sandstones exist within the slice Rio da Serra/Aratu – 1. For illustration purposes, the structural map of top Rio da Serra is presented in the background.
56. Red circles represent average log porosity estimated only where sandstones exist within the slice Rio da Serra/Aratu – 2. For illustration purposes, the structural map of top Rio da Serra is presented in the background.
57. Red circles represent average log porosity estimated only where sandstones exist within the slice Gomo/Rio da Serra – 1. For illustration purposes, the structural map of top Gomo is presented in the background.
58. Red circles represent average log porosity estimated only where sandstones exist within the slice Gomo/Rio da Serra – 2. For illustration purposes, the structural map of top Gomo is presented in the background.
59. Red circles represent average log porosity estimated only where sandstones exist within the slice Gomo/Rio da Serra – 3. For illustration purposes, the structural map of top Gomo is presented in the background.
60. Red circles represent average log porosity estimated only where sandstones exist within the slice Gomo/Rio da Serra – 4. For illustration purposes, the structural map of top Gomo is presented in the background.
61. Red circles represent average log porosity estimated only where sandstones exist within the slice Gomo/Rio da Serra – 5. For illustration purposes, the structural map of top Gomo is presented in the background.
62. Red circles represent average log porosity estimated only where sandstones exist within the slice Tauá/Gomo – 1. For illustration purposes, the structural map of top Gomo is presented in the background.
63. Red circles represent average log porosity estimated only where sandstones exist within the slice Tauá/Gomo – 2. For illustration purposes, the structural map of top Gomo is presented in the background.
64. Red circles represent average log porosity estimated only where sandstones exist within the Água Grande/Itaparica layer. For illustration purposes, the structural map of top Sergi Formation is presented in the background.
65. Red circles represent average log porosity estimated only where sandstones exist within the Sergi Formation layer. For illustration purposes, the structural map of top Sergi Formation is presented in color.
66. Comparison of log derived porosity with core porosity data in the interval 854-859 meters (well 3-ME-0006-BA). The average porosity in this interval, 19.25%, is very close to the average from well log, 19%.
67. Comparison of log derived porosity with core porosity data in the interval 1083-1087 meters (well 3-ME-0006-BA).
68. Depth map of the top of a source rock interval in the middle of Candeias Formation.
69. Distribution of hydrocarbons in the Gomo-Rio da Serra: slice 1 (it is the uppermost slice of this rock unit). The numbers represent percentage of net hydrocarbon shows relative to the layer thickness.
70. Distribution of hydrocarbons in the Gomo-Rio da Serra: slice 2.
71. Distribution of hydrocarbons in the Gomo-Rio da Serra: slice 3.
72. Distribution of hydrocarbons in the Gomo-Rio da Serra: slice 4.
73. Distribution of hydrocarbons in the Gomo-Rio da Serra: slice 5 (it is the lowermost part of this rock unit).
74. Distribution of hydrocarbons in the Tauá-Gomo: slice 1 (upper slice).
75. Distribution of hydrocarbons in the Tauá-Gomo: slice 2 (lower slice).
76. Distribution of wells and seismic lines (2D) in the study area.
77. Study area divided in domains (N,W, C, S, SE and SW) to facilitate the description of the 2D seismic lines quality.
78. 3D view of the 15 wells tied to the seismic. The contour map represents the TWT basement depth.
79. NW-SE section along the center part of the study area. The section goes through the Lamarão gas field, which has a mixed trap and produces in Aratu level. The chronostratigraphic markers are identified in the DA-1 well.
80. Isopach maps of Gomo Member (left) and Sergi Formation (right) – (Figueiredo, et al, 1994; figures extracted from HRT Onshore Chart).
81. NW SE section of the northeast part of study area. Note structural closure along the NW and SE directions.
82. Schematic geologic section showing the main elements of the petroleum systems of the Recôncavo Basin. (modified from Figueiredo et al., 1994; picture taken from HRT Onshore Chart).
83. Structural Map of top Jiquiá stage (in TWT).
84. Structural Map of top Aratu stage (in TWT).
85. Structural map of top Buracica stage (in TWT).
86. Structural map of top Gomo Member (in TWT).
87. Structural map of top Sergi Formation (in TWT).
88. Structural depth map of Top Basement (in TWT).
89. 3D view of the depth converted structural maps in Seistrat 3D. Top of Jiquia stage is shown in green.
90. Example of a well pick table in PetroMod Well Editor.
91. 3D view of the top Jiquiá stage that is adjusted to a well pick inside a circular area.
92. 3D view of the top Gomo Member. The areas in steep slopes (e.g. south of the study area) required more corrections.
93. Depth map (in meters) of top Jiquiá Stage.
94. Depth map (in meters) of top Buracica Stage.
95. Depth map of top Aratu Stage.
96. Depth map of top Rio da Serra Stage.
97. Depth map of top Gomo Member.
98. Depth map (in meters) of top Sergi Formation (it is closer to Itaparica Fm).
99. Depth map (in meters) of top Basement.
100. East-West geological section illustrating the effective source rock (green layer in the middle of the yellow layer) in the study area. The thin source rock interval, the green layer at the base of the Candeias Fm, was defined to test the maximum maturity reached by possible deep source rock intervals in this formation.
101. Isopach map of Candeias Formation.
102. Present day transformation ratio map of the top source rock in the middle Candeias Formation.
103. Present day transformation ratio map of a source rock at the base of Candeias Formation. The scale is the same as in Figure 102.
104. Bulk Mass of Petroleum generated from the source rock in the middle of Candeias Formation. (units: Megatons).
105. Bulk Mass of Petroleum generated from the source rock in the middle of Candeias Formation. Three contour lines are shown: 1, 2 and 3 Mtons.
106. Basin framework and study area (blue line).
107. Basin Framework and the contour lines represent the depth values of the Top of Sergi Fm structural map (from Magnavita, L.P, 1992).
108. South Reconcavo Compartment structural framework, study area and petroleum fields.
109. Basin Framework and main oil and gas fields.
110. Geological section of the Jacuipe field which was studied by Carlotto (2006).
111. Depositional dip oriented schematic facies distribution (Azambuja et al., 2006).
112. Conceptual modeling for the Maracangalha Fm deposition.
113. Location map of the seismic line 26-403
114. Seismic line 26-403 (in TWT) showing Lamarão field and Dias D’Ávila marginal field structural features and seismic patterns.
115. Log characteristics of the producing interval of 1DA1 well and its seismic response (in TWT).
116. Reservoir characteristics and log facies in the slump area of Jacuipe Field, Carlotto thesis.
117. Seismic structural map close to the top of the Ilhas Fm (Pojuca).
118. Geological section correlating the Camaçari and Bom Viver oil interval in the Pojuca Fm (modified from ANP well report).
119. Location map of the seismic lines 26-1363; 26-1576 and 26-1636
120. Structural interpretation and oil shows in the Camaçari and Bom Viver along the seismic line 26-1363.
121. Log (SP or Gama) and seismic patterns of HC shows intervals of the 1CA2 well.
122. Seismic line 26-1576 showing the Bom Viver structural feature.
123. Details of the 1BV2 intervals with HC shows in composite logs and seismic
124. South Recôncavo framework, gravimetric map and marginal fields (HRT &Petroleum Internal Report).
125. Structural seismic map of a “deep unconformity” in the Mapele and Aratu areas.
126. Structural map of the top of “conglomerate zone” that entered in blowout in the 1ME2
127. Location map showing the seismic lines 26-1132 and 26-1728 and the Mapele Field ring fence.
128. Composite line showing the flank of the Mapele Field.
129. Logs details of tested intervals in the 3ME4 well and seismic response.
130. Surface map showing the wells 1CZ1 and 1CZ2 located at the shale diapir and the position of 1CZ3 in the flank of the diapir.
131. Basement seismic structural map and location of the wells 1CZ1, 1CZ2 and 1CZ3
132. Location map of selected lines of Cinzento Field
133. Seismic section 26 – 1575 showing the Cinzento structural feature and an interpreted fault system cutting the blind area of the diapir.
134. Seismic section 26-1653 showing the “diapirs” of Santa Maria and Cinzento cut by an interpreted fault system.
135. Sandstone layer in a thick shale interval (diapir?).
136. Composite log showing the cores 04 and 05 oil bearing and the tested interval.
137. Sandstones, conglomerate and siltstones in a thick shale section (diapir?)
138. Oil shows at shallow depths – No interest.
139. Oil shows. Very tight interval.
140. Oil shows. Very tight interval.
141. Aratu oil shows and test.
142. Rio da Serra oil shows.
143. Rio da Serra formation test in shale high resistivity section
144. 1CGL-1D well structural and depositional location
145. Location map of seismic line 26-1853 and Cantagalo Field
146. Detail of the 1CGL producing interval.
147. Location and general geological context of FAP, FS, PDR and BRP marginal fields.
148. Depositional model for the marginal fields FAP, FS, PDR and BRP
149. Location map and line 26-1341 showing the stratigraphic sequences and structural features drilled by the wells 1FAP1 and 1BRP1 and also the seismic patterns of the sequences.
150. Seismic and log details of the Buracica, Aratu and R. da Serra intervals with HC shows in the 1FAP1 well.
151. Seismic and log details of the Aratu and R. da Serra intervals with hydrocarbon shows in the 1BRP1 well.
152. Seismic line 26-1105 showing the structural feature the Pedrinhas Field and the adjacent 1BRP-1 and Fazenda Sori petroleum discoveries.
153. Buracica sandstones – proximal delta front (?).
154. Aratu sandstones – mid to distal delta front (?).
155. Aratu sandstones Pro-delta to delta front, from base to top of the interval.
156. Aratu Pro-delta sandstones and R. da Serra proximal pro-delta system.
157. Rio da Serra 2700/2900m interval showing oil and gas tests and sandstones sequences.
158. Tested Buracica interval.
159. Some production information about the Dias D’Ávila Field.
160. Historical production of the Dias D’Ávila Field.
161. Some production information about the Camaçari Field.
162. Historical production of the Camaçari Field.
163. Some production information about the Fazenda Alto das Pedras Field.
164. Some production information about the Pedrinhas Field.
165. Historical production of the Pedrinhas Field.
166. Some production information about the Fazenda Sori Field.
167. Historical production of the Fazenda Sori Field.
168. Some production information about the Cantagalo Marginal Field.
169. Historical production of the Cantagalo Field.