in Jurassic and Cretaceous Stratigraphy

More documents

Recommendations

Info

Earth Science Frontiers, Vol. 17, Special Issue, Aug. 2010 ISSN 1005-2321 Lower Kimmeridgian Biostratigraphy and Correlation in the NE Iberian Chain (Spain) Based on Ataxioceratinae Ammonites 114 L. Moliner 1 , F. Olóriz 2 1. Luis Moliner, ENSAYA Laboratory, Aneto n_ 8, 50410 Cuarte de Huerva, Zaragoza, Spain (E-mail: lmoliner@ensaya.es) 2. Federico Olóriz Departamento de Estratigrafía y Paleontología, Facultad de Ciencias, Universidad de Granada, Campus Universitario de Fuente Nueva, 18002, Granada, Spain (E-mail: foloriz@ugr.es) The sections analyzed in the eastern Iberian Chain correspond to neritic sites within a large epicontinental shelf system that occupied eastern and southern Iberia during the Late Jurassic (e.g., Aurell et al., 2002 for an overview). The palaeogeographic setting resulted in environmental conditions related to distance and/or relative poor connection to open waters belonging to outer shelves adjacent to the northwest-Tethyan oceanic fringe (e.g., Moliner and Olóriz, 1999). Thus, water masses during the early Kimmeridgian were inner than those covering typical continental, structured slopes not underpinned by oceanic crust in Tethyan margins, and identified as epioceanic environments (e.g., Olóriz, 1997 and 2000 for extended treatment). A low-energy, mixed carbonate-siliciclastic ramp covered by turbid, nutrient-rich water masses and depths in the range of 30-80m, which was commonly supplied with shedding of fine clastics and carbonates from inner- shelf areas, well adapts sedimentary conditions as interpreted from stratigraphic sections in which the Loriguila Fm. crops out (e.g., Moliner and Olóriz, 1999; Olóriz, 2000; Bádenas and Aurell, 2001; Aurell et al., 2002, and References therein). Shallower environments located northwards and westwards, and locally east- wards, and bottom irregularity was locally conspicuous revealing tectonic instability also determining tectono- eustatic interactions (e.g., Pérez-Urresti and Delvene, 1998; Salas et al., 2001; Benito and Mas, 2006; Delvene et al., 2007; Climent-Domenech et al., 2009). In such an environmental context, ecological pressure on ammonite populations occurred and resulted in common endemism. More than two decades of improving knowledge on ataxioceratin ammonites gathered bed-by-bed from lower Kimmeridgian deposits in the eastern Iberian Chain, E–NE Spain (e.g., from to Moliner and Olóriz, 1984 to 2009a,b and Moliner 2009, and References therein), allow to propose a biostratigraphic chart based on their precise ranges and to evaluate its correlation potential with respect to the Secondary Standard for the Submediterranean Province (e.g., Hantzpergue et al., 1997). Lower Kimmeridgian biostratigraphy has been approached favouring delimitation of biostratigraphic units based on first appearance data (FAD), and three ranges of biostratigraphic divisions have been identified to refine biostratigraphic resolution to the upmost: the biozone, subbiozone and biohorizon (or faunal horizon s. Callomon, 1984) levels. Due to meager ammonite record in marly deposits below the Loriguilla Fm. in lower-to-lowermost horizons of the Sutneria platynota biozone, no precise data about the lowermost Kimmeridgian have been available. The Sutneria platynota biozone has been subdivided, from bottom to top, in the “Orthosphinctes”, Ardescia desmoides, and Schneidia guilherendense subbiozones. No subbiozone subdivision was possible within the “Orthosphinctes” subbiozone, but the Ardes- cia enayi and Ard. desmoides biohorizons were identified within the Ard. desmoides subbiozone, and the Olorizia olorizi and Scneidia guilherandense biohorizons within the Schneidia guilherandense subbiozone. Based on reinterpreted systematics, endemism among ataxioceratins, as it is identified in taxonomic terms, is close to 30% in the Sutneria platynota biozone. The Ataxioceras lothari biozone has been subdivided in the lower Atax. hippolytense and the upper Atax. lothari subbiozones. Within the Atax. lothari subbiozone, the Atax. lothari biohorizon below and the Geyericeras aragoniense biohorizon above have been recognized. Based on reinterpreted systematics, taxonomically expressed endemism among ataxioceratins is close to 50% in the Ataxioceras lothari biozone. The Crussoliceras divisum biozone embraces the upper Lower Kimmeridgian in the area and has been subdivided in the lower C. divisum subbiozone and the upper subbiozone of Orthaspidoceras uhlandi/Gar- nierisphinctes virgatocostatum. Within the Crusso- liceras divisum biozone, and therefore within the stratigraphic range of the index species, no records of Idoceras balderum have been obtained, hence no formal identification of the corresponding and wide- spread recognized subbiozone and/or biohorizon has been realized. Based on reinterpreted systematics, the endemism expressed in taxonomic terms is close to 17% among ataxioceratins in this biozone. FAD based biostratigraphy provides high correlation potential at the biozone and subbiozone levels, and determines the reinterpretation of the lower boun- dary of the Crussoliceras divisum biozone as well as local subbiozone division. Local biohorizons shows their highest correlation potential in the Sutneria platynota Biozone. Higher correlation potential has
Earth Science Frontiers, Vol. 17, Special Issue, Aug. 2010 ISSN 1005-2321 been proved with epicontinental than with epioceanic sections. Ammonitina abundance is highest in the Sutneria platynota biozone, as well as it is the relative abundance of ataxioceratins, which show their lowest value in the Ataxioceras lothari biozone. In contrast, the registered trend in taxonomically expressed endemism at the biozone level indicates maximal values for ataxioceratins in the Ataxioceras lothari biozone. Hence, no direct relationships have been recognized between Ammonitina abundance and the degree of taxonomically expressed endemism in Ataxioceratinae. In two cases endemic taxa serve to characterize biostratigraphic units at the lowest level – i.e., biohorizons. Table 1 Recognized biostratigraphic units for lower Kimmeridgian deposits in NE Iberian Chain and Maestrazgo, prov. Teruel, Spain (based on Moliner, 2009; Moliner and Olóriz, 2009a, b) BIOZONE SUBBIOZONE & BIOHORIZON Lower KIMMERIDGIAN Crussoliceras divisum Ataxioceras lothari Sutneria platynota Key words: Ammonites; Ataxioceratinae; Bio- stratigraphy; Kimmeridgian; Spain References: Aurell M., Meléndez M., Olóriz F. (coords.). The Jurassic. In: Gibbons W., Moreno T. (ed). The Geology of Spain, The Geological Society of London, 2002: 213-253. Bádenas B., Aurell M. Proximal–distal facies relationships and sedimentary processes in a storm dominated carbonate ramp (Kimmeridgian, northwest of the Iberian Ranges Spain). Sedimentary Geology, 2001, 139: 319-340. Benito M.I., Mas R. Sedimentary evolution of the Torrecilla Reef Complex in response to tectoni- cally forced regression (Early Kimmeridgian, Northern Spain). Sedimentary Geology, 2006, 183: 31-49. Callomon J.H. Biostratigraphy, chronostratigraphy and all that – again! In: Michelsen O., Zeiss A. (ed). International Symposium on Jurassic Stratigraphy, Erlangen, Geological Survey of Denmark, Copen- hagen, 1984, 3: 611-624. Climent-Domènech H., Martín-Closas C., Salas R. Charophyte-rich microfacies in the Barremian of the eastern Iberian Chain (Spain). Facies, 2009, 55: 387-400. Delvene G., Pérez-Urresti I., Meléndez G. Upper Jurassic at noroccidental area of Iberian Peninsula Orthaspidoceras uhlandi / Garnierisphinctes virgatocostatum Crussoliceras divisum Ataxioceras lothari Geyericeras aragoniense Ataxioceras lothari Ataxioceras hippolytense Schneidia guilherandense Ardescia desmoides “Orthosphinctes” Schneidia guilherandense Olorizia olorizi Ardescia Desmoides Ardescia Enayi (Spain): Biostratigraphy and main groups of bivalves. Revista Española de Paleontología, 2007, 22(1): 63-76. Hantzpergue P., Atrops F., Enay R., et al. Biostrati- graphie du Jurassique Ouest-Européen et Méditer- ranéen. In: Cariou E., Hantzpergue P. (ed). Zona- tions Paralléles et Distribution des Invertébrés et Microfossiles. Groupe Français Etude Jurassique. Bulletin du centre de recherches Elf Exploration– Production, 1997, Mémoir 17: 87-96. Moliner L. Ataxioceratinae (Ammonitina) del Kim- meridgiense inferior en el NE de la provincia de Teruel (Cordillera Ibérica oriental y Maestrazgo). Ph.D Thesis, Universidad de Granada, Godel S.L., Granada, 2009: 548 (in Spanish). Moliner L., Olóriz F. Fine biostratigraphy in the lowermost part of the Lower Kimmeridgian Platynota Zone of the Celtiberic Chain (Spain). In: Michel- sen O., Zeiss A. (ed). Erlangen: International Sym- posium on Jurassic Stratigraphy, 1984: 2: 503- 514. Moliner L., Olóriz F. The Lower Kimmeridgian Se- ction at Gallipuén. Ammonite Biochronostrati- graphy and Ecostratigraphic Remarks. Profil, 1999, 16: 95-106. Moliner L., Olóriz F. Correlation potential of Lower Kimmeridgian Platynota Zone deposits in north- east Spain. GFF, 2009a, 131: 205-213. Moliner L., Olóriz F. Updated biostratigraphy of Jura- 115
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 10 and 11:
Page 12 and 13:
Page 14 and 15:
Page 16 and 17:
Page 18 and 19:
Page 20 and 21:
Page 22 and 23:
Page 24 and 25:
Page 26 and 27:
Page 28 and 29:
Page 30 and 31:
Page 32 and 33:
Page 34 and 35:
Page 36 and 37:
Page 38 and 39:
Page 40 and 41:
Page 42 and 43:
Page 44 and 45:
Page 46 and 47:
Page 48 and 49:
Page 50 and 51:
Page 52 and 53:
Page 54 and 55:
Page 56 and 57:
Page 58 and 59:
Page 60 and 61:
Page 62 and 63:
Page 64 and 65:
Page 66 and 67:
Page 68 and 69:
Page 70 and 71: Earth Science Frontiers, Vol. 17, S
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

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?