in Jurassic and Cretaceous Stratigraphy

More documents

Recommendations

Info

Earth Science Frontiers, Vol. 17, Special Issue, Aug. 2010 ISSN 1005-2321 48 Fig.1 Lithological and palaeontological characteristic of the Dalichay Formation in northeast of Emamzadeh Hashem, Central Alborz, North Iran
Earth Science Frontiers, Vol. 17, Special Issue, Aug. 2010 ISSN 1005-2321 The Ostracod Fauna of the Section Albstadt-Pfeffingen (Baden-Württemberg) M. Franz 1 , E. Beher 2 , E. Brand 3 , E. Mönnig 4* 1. Regierungspraesidium Freiburg, Abt. 9, Albertstrasse 5, 79104 Freiburg i. Br., Germany (E-mail: matthias.franz@rpf.bwl.de) 2. Goebelstrasse 4, 68776 Ketsch, Germany (E-mail: ebeher@gmx.de) 3. Wilhelmshoeher Weg 49, 34128 Kassel, Germany 4. Naturkunde-Museum Coburg, Park 6, D - 96450 Coburg (E-mail: e.moennig@naturkunde-museum-coburg.de) The ostracod fauna from the Bathonian and lower Callovian of Albstadt-Pfeffingen (Baden-Wuerttem- berg, S Germany) has been studied. The Pfeffingen section is outstanding for its richness in ammonites and therefore has been proposed as Callovian GSSP by Callomon & Dietl (1990, 2000). The study of 13 samples yielded five faunal assemblages, reflecting the major stratigraphic units of the section: the lower Bathonian (Zigzag zone), the middle Bathonian belonging to the Progracilis zone, the upper Bathonian of the Orbis zone (the Discus zone was not sampled) and the lower Callovian belonging to the Herveyi and Koenigi zones. In general the Bathonian assemblages are more diverse than those from the Callovian. At the Bathonian/Callovian boundary a significant number of last occurrences of taxa are recorded. In the Keppleri subzone of the lower Callovian poor micro- faunal assemblages indicate infavourable benthic conditions. In the upper Herveyi and the lower Koenigi zones the number of individuals and the diversity both increase again. The ostracod fauna of the Orbis zone is characterized by the first appearance of several species, e.g. Neurocythere plena, Cytherella limpida, Procytherura ovaliformis, Eucytherura parairregularis and Pleuro- cythere kurskensis. According to Franz et al., (2009) Neurocythere plena is the index species of the N. plena ostracod zone. 25 species were found only in the Orbis zone, 17 of which are represented by a single specimen (see above). 9 further species of the genera Blaszykina, Glyptocythere, Morkhovenicythereis and Oligo- cythereis have their last occurrence in the upper Bathonian. Despite of the very poor fauna – a total of only 13 specimens was obtained from 3 samples – the keppleri horizon of the Herveyi zone can be characterized by its ostracod fauna: the most significant genus is Neurocythere (5 specimens), represented by three subspecies of N. cruciata. Neurocythere cruciata cruciata, which sharply characterizes the Bathonian/ Callovian boundary (Buck et al., 1966: 43), appears in a thin marly layer immediately above the Bathonian/ Callovian boundary at the base of the keppleri horizon, but is very scarce. Franz et al., (2009) recently defined a Neurocythere cruciata ostracod zone for the basal Callovian. The assemblage of the suevicum horizon of the Herveyi zone and the Koenigi zone is also dominated by the genus Neurocythere (31 specimens from a total of 77). The Bairdiidae play a subdominant role, represented by 11 specimens. N. cruciata alata, Terquemula flexicosta and Praeschuleridea subtrigona appear in the suevicum horizon for the first time in this section, Micropneumatocythere aff. convexa and Progono- cythere polonica have their last occurrences. Neuro- cythere caesa caesa, Bythoceratina stimulea, Hutsonia sp. and Pontocyprella atypica appear for the first time in the Koenigi zone. In general the ostracod zonation shows a lower stratigraphical resolution than the ammonite zonation (see e.g. Bate, 2009, Brand & Mönnig, 2009, Bodergat, 1997, Franz et al., 2009, Wilkinson & Whatley, 2009). In Pfeffingen the most prominent boundary is lying at the transition upper Bathonian/lower Callovian. 22 species have their last occurrences in the Orbis zone – not including taxa, which are represented by single specimens. Neurocythere cruciata cruciata, N. cruciata franconica, Praeschuleridea subtrigona and Ter- quemula flexicosta have their first occurrences in the Herveyi zone. The ostracod assemblages of the Bathonian and lower Callovian in the section Albstadt-Pfeffingen are fully marine, but in general are made up of a small number of specimens. The scarcity of specimens in the samples might be due to unfavourable benthic conditions, but this needs further studies. Specimens of the family Progonocytheridae dominate all the studied samples. However, in the Bathonian they are accom- panied by the subdominant families Cytheruridae, Trachyleberididae, Schulerideidae and, less important, Protocytheridae, all of which show a remarkable decrease at the Bathonian/Callovian boundary. The ostracod zonation as established by Franz et al., (2009) – Connexa zone, Capreolata subzone, Plena zone and Cruciata zone – is recognizable in the Batho- nian and the Callovian of Pfeffingen. The highest number of last occurrences is con- centrated in the upper Bathonian. This could probably represent a significant faunal turnover, which requires confirmation through the study of ostracod assemblages from the same time interval in other areas. 49
Page 4 and 5: THE 8 TH INTERNATIONAL CONGRESS ON
Page 6 and 7: EARTH SCIENCE FRONTIERS Short paper
Page 8 and 9: Earth Science Frontiers, Vol. 17, S
Page 104 and 105:
Earth Science Frontiers, Vol. 17, S
Page 106 and 107:
Page 108 and 109:
Page 110 and 111:
Page 112 and 113:
Page 114 and 115:
Page 116 and 117:
Page 118 and 119:
Page 120 and 121:
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
Page 128 and 129:
Page 130 and 131:
Page 132 and 133:
Page 134 and 135:
Page 136 and 137:
Page 138 and 139:
Page 140 and 141:
Page 142 and 143:
Page 144 and 145:
Page 146 and 147:
Page 148 and 149:
Page 150 and 151:
Page 152 and 153:
Page 154 and 155:
Page 156 and 157:
Page 158 and 159:
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
Page 186 and 187:
Page 188 and 189:
Page 190 and 191:
Page 192 and 193:
Page 194 and 195:
Page 196 and 197:
Page 198 and 199:
Page 200 and 201:
Page 202 and 203:
Page 204 and 205:
Page 206 and 207:
Page 208 and 209:
Page 210 and 211:
Page 212 and 213:
Page 214 and 215:
Page 216 and 217:
Page 218 and 219:
Page 220 and 221:
Page 222 and 223:
Page 224 and 225:
Page 226 and 227:
Page 228 and 229:
Page 230 and 231:
Page 232 and 233:
Page 234 and 235:
Page 236 and 237:
Page 238 and 239:
Page 240 and 241:
Page 242 and 243:
Page 244 and 245:
Page 246 and 247:
Page 248 and 249:
Page 250 and 251:
Page 252 and 253:
Page 254 and 255:
Page 256 and 257:
Page 258 and 259:
Page 260 and 261:
Page 262 and 263:
Page 264 and 265:
Page 266 and 267:
Page 268 and 269:
Page 270 and 271:
Page 272 and 273:
Page 274 and 275:
Page 276 and 277:
Page 278 and 279:
Page 280 and 281:
Page 282 and 283:
Page 284 and 285:
Page 286 and 287:
Page 288 and 289:
Page 290 and 291:
Page 292 and 293:
Page 294 and 295:
Page 296 and 297:
Page 298 and 299:
Page 300 and 301:
Page 302 and 303:
Page 304 and 305:
Page 306 and 307:
Page 308 and 309:
Page 310 and 311:
Page 312 and 313:
Page 314 and 315:
Page 316 and 317:
Page 318 and 319:
Page 320 and 321:
Page 322 and 323:
Page 324 and 325:
Page 326 and 327:
Page 328 and 329:
Page 330 and 331:
Page 332 and 333:
Page 334 and 335:
Page 336 and 337:
Page 338 and 339:
Page 340 and 341:
Page 342 and 343:
Page 344 and 345:
Page 346 and 347:
Page 348 and 349:
Page 350 and 351:
Page 352 and 353:
Page 354 and 355:
Page 356 and 357:
Page 358 and 359:
Page 360 and 361:
Page 362 and 363:
Page 364 and 365:
Page 366 and 367:
Page 368 and 369:
Page 370 and 371:
Page 372 and 373:
Page 374 and 375:
Page 376 and 377:
Page 378 and 379:
Page 380 and 381:
Page 382 and 383:
Page 384 and 385:
Page 386 and 387:
Page 388 and 389:
Page 390 and 391:
Page 392 and 393:
Page 394 and 395:
Page 396 and 397:
Page 398 and 399:
Page 400 and 401:
Page 402 and 403:
Page 404 and 405:
Page 406 and 407:
Page 408 and 409:
Page 410 and 411:
Page 412 and 413:
Page 414 and 415:
Page 416 and 417:
410 EARTH SCIENCE FRONTIERS Short P
Page 418 and 419:
P.A. Selden 191 V.I. Katkova 309 P.
show all

in Jurassic and Cretaceous Stratigraphy

Create successful ePaper yourself

Delete template?

Save as template?