Permo-carboniferous Magmatism And Rifting in Europe (Geological Society Special Publication No. 223)

Contents......Page 6
Preface......Page 8
Permo-Carboniferous magmatism and rifting in Europe: introduction......Page 10
Fig. 1. Plate tectonic reconstructions for the Variscan belt and its foreland .........Page 11
Fig. 2. Relative timing of Permo-Carboniferous magmatism, extensional tectonics, basin inversion .........Page 12
Carboniferous-Permian rifting and magmatism in southern Scandinavia, the North Sea and northern Germany: a review......Page 20
Fig. 1. Map of Permo-Carboniferous magmatism, tectonic elements and main structures .........Page 22
Fig. 2. Simplified map showing tectonic framework, and sample locations discussed in .........Page 23
Fig. 3. Bouguer anomaly map with a 50 km low-pass filter, based .........Page 24
Fig. 4. Simplified map of the Oslo Graben showing different rock types .........Page 25
Fig. 5. Initial Sr isotope ratios plotted against ages (obtained from Rb–Sr .........Page 27
Fig. 6. Petrochemical classification diagram for Permo-Carboniferous magmatic rocks in different .........Page 28
Fig. 7. Trace-element concentrations in mafic lavas, dykes and sills in .........Page 30
Fig. 8. (Nb/Ce)[sub(N)] plotted against (Zr/Nd)[sub(N)] for Carboniferous–Permian basaltic lavas and .........Page 31
Fig. 9. Th/Yb plotted against Ta/Yb for Carboniferous–Permian basaltic lavas and .........Page 32
Fig. 10. (a) Initial Nd-Sr isotopic ratios for magmatic rocks in .........Page 33
Fig. 11. Trace-element concentrations in mafic dykes in Scania and Bornholm .........Page 36
Fig. 12. Trace-element concentrations in mafic dykes in the North Sea .........Page 37
Fig. 13. A summary of the magma types, periods of magmatism, estimated .........Page 44
Table 1. Age determinations on Permo-Carboniferous magmatic rocks in different parts .........Page 26
Table 2. An overview over estimated volumes of Permo-Carboniferous magmatic rocks .........Page 29
Timing, geodynamic setting and character of Permo-Carboniferous magmatism in the foreland of the Variscan Orogen, NW Europe......Page 50
Fig. 1. Distribution of Late Carboniferous and Early Permian magmatic rocks in .........Page 51
Fig. 2. Overview of Europe at the end of the Carboniferous, with .........Page 52
Fig. 3. Stratigraphic range of Permo-Carboniferous magmatic rocks in Europe (based .........Page 53
Fig. 4. Dinantian basins in Great Britain and Ireland, with locations of .........Page 54
Fig. 5. Distribution of magmatic rocks of (A) Dinantian and (B) Namurian-Westphalian .........Page 55
Fig. 6. Visean volcanic rocks and Westphalian–Namurian dolerite sills in Derbyshire, .........Page 56
Fig. 7. Visean volcanic and intrusive rocks in the Limerick Basin, SW .........Page 57
Fig. 8. Simplified geological map of SW England showing the location of .........Page 58
Fig. 9. Distribution and thickness variations of the Stephanian–Autunian volcanic rocks .........Page 60
Fig. 10. (a) General geological map of the Whin Sill Complex in .........Page 62
Fig. 11. Distribution of Stephanian–Autunian sedimentary and volcanic rocks in the .........Page 64
Fig. 12. Distribution of Westphalian–Autunian sedimentary and volcanic rocks in the .........Page 65
Fig. 13. The Stephanian and Permian basins of the Massif Central, France .........Page 68
Late Carboniferous-Permian of NW Europe: an introduction to a new regional map......Page 84
Fig. 1. Map showing the distribution of Late Carboniferous–Early Permian magmatic .........Page 85
Fig. 2. Overview map for the Late Carboniferous–Early Permian with structural .........Page 94
Fig. 3. Summary of the timing of the main events during the .........Page 95
Table 1. Wells with Lower Rotliegend volcanic and/or intrusive rocks.......Page 97
Diachronous Variscan late-orogenic collapse in response to multiple detachments: a view from the internides in France to the foreland in the Irish Sea......Page 106
Fig. 1. Location of the study area (rectangle) along the Alleghanian–Variscan .........Page 107
Fig. 2. Schematic summary of orogenic collapse as a response to the .........Page 109
Fig. 3. Distribution of late-orogenic (Stephanian–Early Permian) basins across the .........Page 112
Fig. 4. Transect from the Massif Central to the northern Irish Sea, .........Page 117
Fig. 5. Carboniferous basins of the Armorican Massif: (a) distribution of Dinantian .........Page 121
Fig. 6. Summary of information on Variscan late-orogenic features in the .........Page 125
Fig. 7. Schematic time sections on the Early Carboniferous to Early Permian .........Page 132
Fig. 8. A model of Variscan late-orogenic collapse in response to .........Page 139
Table 1. Summary information on the age and thickness of strata in .........Page 116
Table 2. Summary information on the age and thickness of strata in .........Page 120
Asymmetric lithosphere as the cause of rifting and magmatism in the Permo-Carboniferous Oslo Graben......Page 156
Fig. 1. (a) Simplified structural map of southern Scandinavia. C.D.F., Caledonian Deformation .........Page 157
Fig. 2. (a) Moho depth in km in southern Scandinavia (Kinck et .........Page 159
Fig. 3. Ansys model set-up. Left panel: boundary conditions for the .........Page 160
Fig. 4. Horizontal strain ε[sub(xx)] distributions computed for the last million years .........Page 163
Fig. 5. Modelled thinning (%) as a function of the lithosphere thickness .........Page 164
Fig. 6. Horizontal strain ε[sub(xx)] distributions computed for different lithosphere thickness contrasts .........Page 165
Fig. 7. Modelled thermal evolution for model Δthi = 55 km. Left panel: .........Page 167
Fig. 9. Computed geotherms for the lithosphere, after 10 Ma of stretching .........Page 168
Fig. 10. Model Δthi = 55 km. (a) Maximum base lithosphere uplift predicted for .........Page 169
Table 1. Parameters used in the modelling. Thermal parameters after Balling (1995), .........Page 162
Late Carboniferous-Permian tectonics and magmatic activity in the Skagerrak, Kattegat and the North Sea......Page 174
Fig. 1. Overview map for the Late Carboniferous–-Early Permian with structural .........Page 176
Fig. 2. Overview map of the study area with the main structural .........Page 177
Fig. 3. Line drawing profiles of seismic sections. Locations of the profiles .........Page 179
Fig. 5. Interpretation of seismic line K83–-005 through the Hans-1 well .........Page 181
Fig. 6. Interpretation of seismic line DN84D-3 with a projection of the .........Page 182
Fig. 7. (a) Well correlation panel of Danish wells from the Kattegat .........Page 183
Fig. 8. Interpretation of a part of seismic line CAST-118A through .........Page 184
Fig. 9. Interpretation of a part of seismic line GLD92–401 (courtesy .........Page 185
Fig. 10. Interpretation of a part of seismic line GLD92–204A (courtesy .........Page 186
New constraints on the timing of late Carboniferous-early Permian volcanism in the central North Sea......Page 194
Fig. 1. Map showing the distribution of Lower Rotliegend volcanic rocks, Upper .........Page 196
Fig. 3. (a) Map showing the location of offshore wells that penetrate .........Page 197
Fig. 4. (a) Total alkalis v. SiO[sub(2)] (wt%) plot of selected samples .........Page 199
Fig. 5. (a) [sup(40)]Ar/[sup(39)]Ar step-heating spectrum for whole-rock sample 9125.5 .........Page 202
Fig. 6. Two-dimensional migrated seismic section (courtesy of Amerada Hess) and .........Page 203
Fig. 7. Two-dimensional migrated seismic section (courtesy of TGS NOPEC AS) .........Page 204
Table 1. Major-, trace- and rare earth element data of basalt samples from well 39/2-4.......Page 200
Table 2. [sup(40)]Ar/[sup(39)]Ar data for samples 9125.5 and 9115.0.......Page 201
Carboniferous and Permian magmatism in Scotland......Page 212
Fig. 1. Map of the Midland Valley and southern Scotland showing the .........Page 213
Fig. 2. Lithostratigraphical and geographical distribution of Carboniferous and Early Permian volcanic .........Page 214
Fig. 3. Distribution of alkali dolerite sills in the Scottish Midland Valley. (After Cameron & Stephenson 1985.)......Page 217
Fig. 4. Map showing the location and azimuth distribution of the main .........Page 219
Fig. 5. Distribution of Stephanian tholeiitic dykes and sills in the Scottish .........Page 220
Fig. 6. Total alkali–silica diagram for Scottish Carboniferous and Permian basic .........Page 222
Fig. 7. εNd v. εSr for Scottish Carboniferous and Permian igneous rocks .........Page 223
Fig. 9. Al[sub(2)]O[sub(3)] v. MgO wt% variation diagram for Dinantian and Silesian–Permian .........Page 224
Fig. 10. Ce/Y v. Zr/Nb for Scottish Carboniferous and Permian basic (MgO > 4 wt%) igneous rocks .........Page 226
[sup(40)]Ar/[sup(39)]Ar geochronology of Carboniferous-Permian volcanism in the Midland Valley, Scotland......Page 236
Fig. 2. Summary chart showing Midland Valley stratigraphy (modified after Browne & 1989; .........Page 237
Fig. 3. Placed against the Gradstein & Ogg (1996) timescale, a comparison .........Page 240
Fig. 4. Age and K/Ca spectra for the Garleton Hills Volcanic Formation, .........Page 247
Fig. 5. Age and K/Ca spectra for the Clyde Plateau Volcanic Formation .........Page 248
Fig. 6. Age and K/Ca spectra for the NW Edinburgh intrusions. Horizontal .........Page 249
Fig. 7. Age and K/Ca spectra for the western MVS intrusions. Horizontal .........Page 251
Fig. 8. Relative frequency distribution analysis calculated by summing the individual Gaussian .........Page 252
Table 1. Sample location, type and mineral separate for the De Souza .........Page 239
Table 2. Summary of K–Ar and [sup(40)]Ar/[sup(39)]Ar ages for igneous rocks .........Page 241
Helium isotope signature of lithospheric mantle xenoliths from the Permo-Carboniferous magmatic province in Scotland - no evidence for a lower-mantle plume......Page 260
Fig. 1. Location map of the British Isles showing the xenolith and .........Page 261
Fig. 2. Photomicrographs of primary, high-pressure CO[sub(2)] inclusions in olivine from .........Page 265
Fig. 3. The variation in [sup(3)]He/[sup(4)]He (R) normalized to the atmospheric ratio (R[sub(a)] .........Page 267
Table 3. Helium isotope data and [sup(20)]Ne concentrations for the Scottish xenolith .........Page 268
Table 1. Selected microprobe analyses illustrating the compositional variation in olivine from .........Page 263
Table 2. Fluid inclusion data.......Page 266
Table 4. Model calculations of source enrichment at different times using standard .........Page 270
Permo-Carboniferous extension-related magmatism at the SW margin of the Fennoscandian Shield......Page 276
Fig. 1. Distribution of Permo-Carboniferous igneous rocks in central and western .........Page 277
Fig. 2. (a) Fault pattern along the SW margin of the Fennoscandian .........Page 278
Fig. 3. Microprobe analyses of pyroxenes plotted in the pyroxene quadilateral to .........Page 284
Fig. 4. Total alkalis v. SiO[sub(2)] classification diagram for volcanic rocks (Le Maitre 2002).........Page 290
Fig. 5. Major-and trace-element variation diagrams v. Mg-number for .........Page 291
Fig. 6. Different trends in bivariate element plots indicating the existence of .........Page 293
Fig. 7. Primitive mantle-normalized trace-element variation diagrams for the Scania .........Page 294
Fig. 9. (a) Variation of SiO[sub(2)] v. Mg-number (Mg#). Relatively constant .........Page 295
Fig. 10. (a) Mantle-normalized trace-element patterns for the mafic dykes .........Page 296
Fig. 11. Selected bivariate plots of major (wt%) and trace (ppm) elements .........Page 299
Fig. 13. Normalized trace-element patterns of the Vastergotland dolerites (data: this .........Page 300
Fig. 14. Sketch (not to scale) of the tectono-magmatic processes that .........Page 301
Table 1. Representative analyses of major and minor minerals in the Scania .........Page 281
Table 2. Concentrations of major (wt%) and trace elements (ppm) in dolerite .........Page 286
Table 4. Results of Sm–Nd isotope analyses of Scania dykes (D I/II .........Page 289
Post-Variscan evolution of the lithosphere in the Rhine Graben area: constraints from subsidence modelling......Page 306
Fig. 1. Location map of Rhine rift system in the northern Alpine .........Page 307
Fig. 2. Depth map of Moho discontinuity within Central Europe (after Dèzes .........Page 308
Fig. 3. Variscan tectonic framework of the Rhine rift area, showing the .........Page 310
Fig. 4. Stephanian–Early Permian tectonic framework of Rhine rift area, showing .........Page 313
Fig. 5. Central segment of the deep reflection-seismic line DEKORP 2S, .........Page 317
Fig. 6. Restored isopach map of Triassic series, contour interval 500m (after .........Page 319
Fig. 7. Air-loaded tectonic subsidence curves for selected wells. Black squares .........Page 320
Fig. 8. Modelled subsidence curves for wells in the Paris Basin.Black .........Page 321
Fig. 10. Modelled subsidence curves for wells on the Franconian Platform. Black .........Page 322
Fig. 11. Conceptual model for the Late Carboniferous–end of Cretaceous evolution .........Page 327
Table 1. Input parameters and modelling results for Permo-Carboniferous thermal destabilization of the lithosphere.......Page 323
Timing of Upper Carboniferous-Permian horst-basin formation and magmatism in the NW Thuringian Forest, central Germany: a review......Page 336
Fig. 2. Distribution of crystalline basement and molasse basins, as well as .........Page 337
Fig. 3. (a) Geology of the NW Thuringian Forest, (b) Geological map of the Ruhla Crystalline Complex.......Page 338
Fig. 4. Synopsis of age data and orientation of intrusions in the .........Page 340
Fig. 5. Schematic geological profile through the Ruhla Crystalline Complex and its .........Page 342
Fig. 6. Stratigraphy, lithology, volcanism and ages of the Upper Carboniferous and .........Page 343
Fig. 7. Schematic block diagrams illustrating the structural–magmatic evolution between the .........Page 347
New [sup(40)]Ar/[sup(39)Ar ages and geochemistry of late Carboniferous-early Permian lamprophyres and related volcanic rocks in the Saxothuringian Zone of the Variscan Orogen (Germany)......Page 352
Fig. 1. Tectonic overview map and the geological setting of the studied .........Page 354
Fig. 2. (a)–(e) Step-wise heating age spectra of amphibole and .........Page 361
Fig. 3. (a)–(f) Step-wise heating age spectra of tri-octahedral .........Page 362
Fig. 4. Photomicrographs of textures of lamprophyres from the Saxothuringian Zone, (a) .........Page 363
Fig. 5. Whole-rock concentrations of Ni (ppm) v. Mg# (FeO = FeO[sub(tot)]) .........Page 368
Fig. 6. (a)–(e) Primitive mantle-normalized incompatible element patterns of Permo-Carboniferous .........Page 369
Fig. 7. (a)–(e) Chondrite-normalized REE patterns of Permo-Carboniferous, post-kinematic .........Page 370
Table 1. [sup(40)]Ar/[sup(39)]Ar data (MS 10 AEI, Leeds University).......Page 358
Table 2. Summary of [sup(40)]Ar/[sup(39)]Ar dating results; ages in Ma, preferred .........Page 364
Table 3. Selected, representative major and trace-element data for lamprophyres from .........Page 366
Magmatism of the late Variscan intermontane Saar-Nahe Basin (Germany): a review......Page 378
Fig. 1. (a) Position of the Carboniferous–Permian Saar–Nahe(–Lorraine) Basin .........Page 379
Fig. 2. Variation of FeO[sub(tot)]/MgO v. SiO[sub(2)] for the SNB magmatic .........Page 391
Fig. 3. (a) Ni v. Mg# (FeO = FeO[sub(tot)]) for basalts and basaltic andesites, .........Page 392
Fig. 4. Zr/TiO2 v. Nb/Y (Winchester & Floyd 1977) for the .........Page 393
Fig. 5. Cl-chondrite normalized REE patterns for igneous rocks of the .........Page 394
Fig. 6. MORB-normalized trace-element patterns for basalts and basaltic andesites .........Page 395
Fig. 8. δ[sup(18)]O(SMOW) v. ([sup(87)]Sr/[sup(86)]Sr)[sub(i)] for igneous rocks of the .........Page 396
Fig. 9. (a) R1-R2 diagram (De la Roche et al. 1980) .........Page 398
Fig. 10. (a) Nb/Y v. Th after Romer et al. (2001) .........Page 400
Table 1. Representative whole-rock analyses of major and trace-element compositions of SNB igneous rocks.......Page 387
Table 2. Whole-rock Nd, Sm, Rb, and Sr elemental abundances and .........Page 389
Table 3. Whole-rock and mineral separate δ[sup(18)]O (SMOW) [%o] values for .........Page 390
Geochemistry and mineralogy of Rotliegend metavolcanic mafic rocks from Poland: pervasive low-grade metamorphism versus parent rock signature......Page 410
Fig. 1. (a) Thickness of the volcanic sequence in the NE German .........Page 411
Fig. 2. Cross-section through the Permian rock sequence based on seismic .........Page 412
Fig. 3. (a) Pseudomorphic replacement after olivine (Ol ps) in altered mafic rock. .........Page 414
Fig. 4. Fragment of altered volcanic rock composed of pseudomorphic corrensite replacement .........Page 415
Table 4. Bulk-rock trace-element, carbon and sulphur contents of altered volcanic rocks from the GWR.......Page 420
Fig. 6. Nb/Y v. Zr/TiO[sub(2)] discrimination diagram (after Winchester & Floyd 1977) .........Page 421
Fig. 7. Zr v. Hf variation in GWR samples, East Brandenburg Mg-andesite .........Page 422
Fig. 8. Ta/Yb v. Th/Yb diagram (after Pearce 1983) for .........Page 423
Fig. 9. REE patterns normalized to Cl chondrite abundances compared with the .........Page 424
Fig. 11. Appearance of secondary minerals in altered GWR volcanic rocks with .........Page 425
Fig. 12. Petrogenetic grid for low-temperature and low-pressure metamorphic fades .........Page 426
Table 1. Mineralogy of altered Rotliegend volcanic rocks from the GWR.......Page 416
Table 2. Representative fluid inclusion results from quartz in altered volcanic rocks from the GWR.......Page 418
Table 3. Bulk-rock compositions of altered Permian volcanic rocks from the .........Page 419
Carboniferous-Permian mafic magmatism in the Variscan belt of Spain and France: implications for mantle sources......Page 432
Fig. 1. Schematic diagram depicting the Carboniferous–Permian European–NW African magmatic .........Page 434
Fig. 2. Sketch maps of the Iberian peninsula (a) and the Massif .........Page 435
Fig. 3. SiO[sub(2)] (wt%) v. Nb/Y classification diagram (Winchester & Floyd .........Page 443
Fig. 4. (a) K[sub(2)]O-SiO[sub(2)] diagram for all the non-lamprophyric volcanic .........Page 444
Fig. 6. MgO (wt%) v. Zr (ppm) contents for the studied Carboniferous .........Page 445
Table 3. Sr, Nd and Pb isotope composition of separated amphibole phenocrysts .........Page 446
Fig. 9. Th/Yb v. Ta/Yb discrimination diagram (Pearce 1982) for .........Page 447
Table 1. Sample localities and characteristics of the studied samples. The mineralogy .........Page 436
Table 2. Major (wt%) and trace-element (ppm) analyses of the rocks .........Page 439
Permian magmatism and basin dynamics in the southern Pyrenees: a record of the transition from late Variscan transtension to the early Alpine extension......Page 456
Fig. 1. (a) Location of the Pyrenean Axial Zone in the context .........Page 457
Fig. 2. Schematic cross-section of a typical Stephanian-Permian basin in the .........Page 458
Fig. 3. Simplified geological maps of the studied areas, showing the location .........Page 459
Fig. 4. Stratigraphic sections for the studied areas, showing the emplacement relationships .........Page 460
Fig. 5. Schematic model of a dextral shear zone and the development .........Page 463
Fig. 6. Rose diagrams for (a) syn-sedimentary faults and dyke orientations in .........Page 464
Fig. 7. Composition and classification (Morimoto et al. 1988) of the analysed .........Page 468
Fig. 8. Total alkali-silica diagram (Le Maitre 2002) for the volcanic rocks .........Page 471
Fig. 9. SiO[sub(2)] wt% v. Nb/Y plot (Winchester & Floyd 1977) for .........Page 472
Fig. 10. Primordial-mantle-normalized (Sun & McDonough 1989) REE plots for (a) the .........Page 473
Fig. 11. Primordial-mantle-normalized (Sun & McDonough 1989) trace-element variation diagrams .........Page 474
Fig. 12. εNd[sub(t)] v. εSr[sub(t)] plot for the studied rocks (/ = 267 Ma) and .........Page 476
Table 1. Representative compositions and structural formulae of pyroxene phenocrysts in the .........Page 467
Table 2. Selected whole-rock compositions for Episode IV (trachyandesite) and Episode V .........Page 469
Table 3. Sr–Nd isotope composition of basalt (ELA–25) and dolerites of .........Page 475
Lower Permian magmatism of the Iberian Chain, Central Spain, and its relationship to extensional tectonics......Page 482
Fig. 1 . (a) Location of the Iberian Chain in the context of .........Page 483
Fig. 2. Simplified map of the Variscan outcrops of the Iberian Chain. .........Page 485
Fig. 4. Stratigraphic sections for selected outcrops (locations given in Fig. 2) with volcaniclastic deposits.......Page 486
Fig. 5. Geological sketch map of the Reznos area (Lago et al. .........Page 487
Fig. 6. Three-dimensional reconstruction of the Reznos outcrop, based on well-log .........Page 488
Fig. 7. Details of emplacement structures in andesitic dykes (Montalban Anticline area): .........Page 489
Fig. 8. Details of xenolith–rock relationships, (a) Partially assimilated garnet-bearing metapelitic .........Page 490
Fig. 9. Time and space sequence of the different intrusive and volcaniclastic .........Page 492
Fig. 10. SiO[sub(2)] v. Nb/Y plot (Winchester & Floyd 1976) for all .........Page 497
Fig. 11. Combined Na[sub(2)]O + K[sub(2)]O and CaO v. SiO[sub(2)] plot for the .........Page 498
Fig. 12. Oxide (wt%) variation trends v. SiO[sub(2)] for the studied rocks .........Page 499
Fig. 13. Primitive Mantle-normalized (Sun & McDonough 1989) multi-element plots for selected .........Page 500
Fig. 14. Chondrite-normalized (Boynton 1984) REE patterns for representative samples of the studied hypabyssal rocks.......Page 501
Fig. 15. εNd[sub(t)] v. [sup(87)]Sr/ [sup(86)]Sr[sub(t)] plot for the analysed Lower Permian .........Page 502
Fig. 16. Comparison of the late Variscan magmatic evolution in the Iberian .........Page 503
Table 1. Representative whole-rock major- and trace-element analyses for the magmatic .........Page 495
Table 2. Sr and Nd isotope compositions of selected andesitic (MON, MONT, .........Page 496
C......Page 508
H......Page 509
M......Page 510
O......Page 511
S......Page 512
V......Page 514
Z......Page 515