Petroleum Geology of. Southern Iraq. Petroleum Geology of. Studied Area. Target Exploration Target Exploration. barr. A Target Exploration Report

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1 Page1 barr Target Exploration barr Target Exploration Target Exploration Petroleum Geology of Southern Iraq Petroleum Geology of Studied Area Southern A Target Exploration Report Iraq

2 Page2 The Report This is an extensive study of the petroleum geology of southern Iraq; covering stratigraphy, structural styles, geothermal gradients, potential source rocks and hydrogeology. The report concludes with an evaluation of the exploration potential of the entire Phanerozoic sequence of South Iraq. The report is in two volumes, 350 pages of text, 133 maps and figures, 103 pages of appendices, 14 pages of references and 19 enclosures. Contents ITEM VOLUME ONE CHAPTER I: INTRODUCTION 1.1 Location and Physiography Regional Geological Setting Previous Work Aim and Materials of Study Method of Study 28 CHAPTER II: PRE-CAMBRIAN, INFRA-CAMBRIAN AND PALEOZOIC SYSTEMS P.1. Introduction Pre-Cambrian Basement 48 II. 2 Infra-Cambrian The Cambrian-Ordovician Rocks The Silurian Rocks PAGE

3 Page The Lower-Middle Devonian Rocks The Famennian-Lower Tournaisian Rocks The Upper Tournaisian Autuniatin Rocks The Kungurian-Kazanian Rocks The Tatarian Sediments 79 CHAPTER III THE MESOZOIC SYSTEM The Tatarian Ladinian Rocks The Carian-Rhaetian Rocks The Hettangian Pliensbachian Rocks The Toarcian? Lower Aalenian Rocks The Upper Aalenian Bathonian Rocks 105 III.6 The Callovian Lower Tithonian Rocks The M.Tithonian Aptian Rocks The Albian Basal Cenomanian Rocks The Cenomauian Lower Turonian Rocks 153 III.10 The Coniacian Lower Maestrichtian Rocks The Maestrichtian Rocks 179 CHAPTER IV: THE CENOZOIC SYSTEM The Paleocene Ypresian Rocks 192 IV.2 The Lutetian Priabonian Rocks 203 IV.3 The Oligocene Rocks 213 IV.4 The Aquitanian Rocks 221 IV.5 The Burdigalian Rocks 229 IV.6 The? Lower-Middle Miocene Rocks 236 IV.7 The Upper Miocene-Pleistocene Rocks 244 IV.8 The Holocene Sediments

4 Page4 CHAPTERV: PRESENT STRUCTURAL CONDITIONS 263 P.II.1 Introduction 264 V.1 Present Surface Structural Features 266 V.2 Present and Historical Seismicity 268 V.3 Geophysical Data 268 CHAPTER VI: STRUCTURAL GROWTH AND DEVELOPMENTS 275 VI.l Anticlinal Growths 275 VI.2 The Effects of Structural Features on Sedimentation 287 CHAPTER VII: PETROLEUM EXPLORATION AND PROSPECTS OF SOUTHERN IRAQ 292 P.III. Introduction 293 VII.l Exploration Elements 298 VII.2 Petroleum Traps 316 VII.3 Petroleum Prospects of Southern Iraq 344 CHAPTER VIII: SUMMARY AND CONCLUSIONS 347 REFERENCES 351 FIGURES Location map Physiographic map of S. Iraq Topographic map of S. Iraq Generalised tectonic map of Iraq Main tectonic and structural elements of Iraq Regional rock units correlation (Naqib, 1967) 26 I Location map 32 I Well location map of N. Iraq 33 I Lithological log heading 35 P Stratigraphic grouping, Basrah area (Owen and Nasr, l958) PAGE 16 32

5 Page Generalized geological map of Hijaz area (Helal, 1968) Geological map of Jabal Sanam (Naqib, 1970) Nomenclature and correlation of the Cambrian rocks around the Arabian Shield Age relationships of Paleozoic rock units in S. Iraq and circumferential territories Correlation diagram of Paleozoic formations around S. Iraq Sigillaria (Stylodendron) stem from NijiJi Formation, Ga ara area Age relationships of Triassic-Jurassic Formations in S. Iraq and circumferential areas Stratigraphic correlation diagram of the Tatarian-Ladinian rocks Inferred isopach lithofacies map (Tatarian Ladinian rocks) Inferred isopach lithofacies map (Carnian Rhaetian rocks) Stratigraphic correlation diagram of the?hettangian-bathonian rocks 96 III.3.2 Generalised isopach lithofacies map (Hettangian-Pliensbachian rocks) Generalised isopach lithofacies map (Toarcian-? L.Aalenian rocks) 103 III.5.l Generalised isopach lithofacies map (? U.Aalenian-Bathonian rocks) 109 III.6.l Isopach and quantitative lithofacies map (Callovian-L.Tithonian rocks) Stratigraphic cross section (Callovian L.Tithonian rocks) Dominant environments of deposition (Callovian-L.Tithonian rocks) 116 III.7.la Stratigraphic cross section (M. Tithonian Aptian rocks) 119 III.7.lb Stratigraphic cross section (M. Tithonian Aptian rocks) Isopach and quantitative lithofacies map (M. Tithonian- L.Valanginian rocks) Dominant environments of deposition (M.Tithonian-L.Valanginian rocks) 126 III.7.4a Isopach and quantitative lithofacies map (Valanginian-Aptian rocks) 130 III.7.4b Enlargement of the eastern part of Figure III.7.4a Stratigraphic cross section (Valanginian Aptian rocks) Dominant environments of deposition (Valanginian-Aptian rocks) 134 III.8.la Isopach and quantitative lithofacies map (Albian Basal Cenomanian rocks)

6 Page6 III.8.lb Enlargement of the eastern part of Figure III.8.la Stratigraphic cross section of the Albian-Basal Cenomanian rocks Inferred distribution of dominant sedimentary environments; Albian-B. Cenomanian rocks Isopach map of Nahr Umr Formation Stratigraphic cross section of the Albian-Basal Cenomanian rocks Shale isolith map (Cenomanian-L. Turonian rocks) Sand isolith map (Cenomanian-L. Turonian rocks) 158 III.9.3a Isopach and quantitative lithofacies map (Cenomanian-L. Turonian rocks) 161 III.9.3b Enlargement of the eastern part of Figure III.9.3a Stratigraphic cross section (Cenomanian L. Turonian rocks) Stratigraphic cross section (Cenomanian L. Turonian rocks) Inferred depositional environments (Cenomanian L. Turonian rocks) 166 III.10.la Isopach-lithofacies map (Coniacian L.Maestrichtian rocks) 174 III.l0.lb Enlargement of the eastern part of Figure III.l0.la Stratigraphic cross section (Coniacian L. Maestrichtian rocks) Inferred deposition environments (Coniacian L. Maestrichtian rocks) 178 III.1l.la Isopach and quantitative lithofacies map (Maestrichtian rocks) 185 III.ll.lb Enlargement of the eastern side of Figure III.ll.la Stratigraphic cross section (Maestrichtian rocks) 187 III.ll.3 Inferred environments of deposition (Maestrichtian rocks) 189 IV.l.la Isopach and quantitative lithofacies map (Paleocene-Ypresian rocks) IV.1.lb Enlargement of the eastern side of Figure IV.1.la 196 IV.l.2 Stratigraphic cross section (Paleocene Ypresian rocks) 197 IV.l.3 Inferred dominant environments of deposition (Paleocene-Ypresian rocks) 200 IV.2.la Isopach and quantitative lithofacies map (Lutetian-Priabonian rocks 205 IV.2.lb Enlargement of the eastern side of Figure IV.2.la 207

7 Page7 IV.2.2 Stratigraphic cross section (Lutetian-Priabonian rocks) 208 IV.2.3 Dominant environments of deposition (Lutetian-Priabonian rocks) 210 IV.3.la Isopach and quantitative lithofacies map (Oligocene rocks) 216 IV.3.lb Enlargement of the eastern side of Figure IV.3.1a 217 IV.3.2 Stratigraphic cross section (Oligocene rocks) 218 IV.3.3 Dominant environments of deposition (Oligocene rocks) 220 IV.4.la Isopach and quantitative lithofacies map (Aquitanian rocks) 223 IV.4.1b Enlargement of the eastern side of Figure IV.4.la 224 1V.4.2 Stratigraphic cross section (Aquitanian rocks) 225 IV.4.3 Inferred environments of deposition (Aquitanian rocks) 227 IV.5.la Isopach and quantitative lithofacies map (Burdigalian rocks) 231 IV.5.lb Enlargement of the eastern side of Figure IV.5.la 232 IV.5.2 Stratigraphic cross section (Burdigalian rocks) 233 IV.5.3 Inferred environments of deposition (Burdigalian rocks) 235 IV.6.la Isopach and quantitative lithofacies map (? L-M. Miocene rocks) 238 IV.6.lb Enlargement of the eastern side of Figure IV.6.la 239 IV.6.2 Stratigraphic cross section (? L.-M. Miocene rocks) 240 IV.6.3 Inferred dominant environments of deposition (? L.-M. Miocene rocks) 242 IV.7.la Isopach and quantitative lithofacies map (U. Miocene-Pleistocene rocks) 246 IV.7.lb Enlargement of the eastern side of Figure IV.7.la 247 IV.7.2 Stratigraphic cross section (U. Miocene Pleistocene rocks) 248 IV.7.3 Inferred dominant environments of deposition (U. Miocene-Pleistocene rocks 251 IV.8.1 Isopach map of the Holocene sediments 257 IV.8.2 Stratigraphic cross section (Holocene rocks) 258 V1.1 Inferred surface structural alignments in S. Iraq 267 VI.1 The sub-surface structural (style) zones in S. Iraq

8 Page8 VI.1.1 Percentage of present structural development (N. Umr structure) VI.1.2 Percentage of present structural development (Rumaila anticline) 279 VI.1.3 Percentage of present structural development (Zubair anticline) 280 VI.1.4 Thickness variations in two flank wells (Rumaila anticline) 281 VI.1.5 Percentage of present structural development (Buzurgan anticline) 282 VI.1.6 Percentage of present structural development (Buzurgan anticline) 283 VI.l.7 Ratio of Formational thickness of two flank wells (Buzurgan anticline) 284 VI.I.8 Percentage of present structural development (Kif1 structure) 285 VI.I.9 Ratio of formational thickness of two flank wells (Kifl structure) 286 P.III.I.I Oil fields localities VII.1.1 Total extract/non carbonate carbon of cuttings (Zubair Fm.) VII.1.2 Approximate geothermal gradient map of S. Iraq 305 VII.1.3 Oil window in S. Iraq, cross sectional diagram 306 VII.1.4a Isosalinity and potentiometric surface contours (Callovian-L. Tithonian rocks) 310 VII.1.4b Isosalinity and potentiometric surface (M. Tithonian L. Valanginian rocks) 311 VII.1.4c Isosalinity and potentiometric surface contours (Zubair Fm.) 312 VII.1.4d Isosalinity and potentiometric surface contours (N. Umr Fm.) 313 VII.1.4e Isosalinity and potentiometric surface contours (Cenomanian-L. Turonian rocks) 314 VII.1.4f Isosalinity and potentiometric surface contours L. Maestrichtian rocks) 315 VII.2.1 Correlation diagram of the quantitative lithological anomalies of structural developments and petroleum occurrences in S. Iraq 318 VII.2.2.1a Lap out map (Bathonian) 323 VII.2.2.1b Structural and sub-crop map (Bathonian) 324 VII.2.2.2a Lap out map (M. Tithonian) 325 VII.2.2.2b Structural and sub crop map (M. Tithonian) 326 VII.2.2.3a Lap out map (U.Aptian/L.Albian) 328

9 Page9 VII.2.2.3b Structural and sub-crop map (U.Aptian/L.Albian) VII.2.2.4a Lap out map (U.Albian/L. Cenomanian) 330 VII.2.2.4b Structural and sub crop map (U.Albian/L.Cenomanian) 331 VII.2.2.5a Lap out map (L., Turonian) 332 VII.2.2.5b Structural and sub-crop map (L. Turonian) 333 VII.2.2.6a Lap out map (L. Maestrichtian) 334 VII.2.2.6b Structural and sub-crop map (L. Maestrichtian) 335 VII.2.2.7a Lap out map (U. Maestrichtian) 336 VII.2.2.7b Structural and sub-crop map (U. Maestrichtian) 337 VII.2.2.8a Lap out map (L. Eocene) 338 VII.2.2.8b Structural and sub-crop map (L. Eocene) 339 VII.2.2.9a Lap out map (U. Eocene/M. Oligocene) 340 VII.2.2.9b Structural and sub-crop map (U. Eocene/M. Miocene) 341 VII a Lap out map (Burdigalian/M. Miocene) 342 VII b Structural and sub-crop map (Burdigalian/M. Miocene) 343 VII b Informal stratigraphic grouping of the rock stratigraphic units of S. Iraq 348 Appendix.III.7 Characteristic gamma log motifs (Selley, l976b) Appendix.III.11a Foraminiferal facies (reefal environments) Appendix.III.11b Foraminiferal facies (open neritic environments) Appendix.IV Geothermal gradient graphs of S. Iraq VOLUME TWO: APPENDICES AND ENCLOSURES APPENDICES I-VII A.I. Depth and thicknesses of the rock units at the control wells 3 3 A.II. Lithological percentages and ratios of the rock units in the control wells aid localities 41 A.III. Indicators of the environments of deposition 56 A.IV. Data of present structural developments in Southern Iraq 78

10 A.V. Geothermal gradient data of Southern Iraq 98 A.VI. Mud pressure data of some of the Mesozoic intervals in S. Iraq 101 A.VII Formation water resistivity and estimated NaC1 concentration 108 Enclosures I to XIX 1. Geological map of S. Iraq 2. Age relationships of the rock units in S. Iraq, SW Iran and N. Saudi Arabia 3. Lithological log of Well Ag-2 4. Lithological log of Well Af-1 5. Lithological log of Well Bu-2 6. Lithological log of Well Dujaila-1 7. Lithological log of Rutbah and Ga ara exposures 8. Lithological log of Well Kf-1 9. Lithological log of Well Musaiyib Lithological log of Well Rachi Lithological log of Well Ru Lithological log of Well Sf Lithological log of Well Sa Lithological log of Well Sb Lithological log of Well Ub Lithological log of Well Zu Tectonic map of Southern Iraq 18. Bouguer gravity anomalies in S. Iraq 19. Geochemical source rock analysis of Zubair formations shale Page10

11 Page11 barr This report is immediately available from Target Exploration Target Exploration Click here to order your copy For other information, contact: M. Casey Target Exploration Consultants 65 Kenton Court, London W14 8NW, UK. Revised 28/09/2017