Tertiary basins of Spain the stratigraphic record of crustal kinematics Edited by PETER F. FRIEND AND CRISTINO J. DABRIO CAMBRIDGE UNIVERS1TY PRESS Tertiary basins of Spain the strati graphic record of crus tal kinematics EDITED BY PETER F. FRIEND Department of Earth Sciences, University af Cambridge AND CRISTlNO J. DABRIO Departamento de Estratigrafia, Facultad de Ciencias Geo16gicas and Instituto de Geologia Economica, CSIC, Universidad Compiutense, Madrid, Spain _CAMBRIDGE ::: UNIVERSITY PRESS Published by the Press Syndicate of the University of Cambridge The Pitt Building, Trumpington Street, Cambridge CB2 1 R P 4 0 West 20th Street, New York, NY 10011--4211, USA 10 Stamford Road, Oakleigh, Melbourne 3166, Australia © Cambridge University Press 1996 First published 1996 Printed in Great Britain at the University Press, Cambridge A catalogue record for this book is available from the British Library Library of Congress cataloguing in publication data Tertiary basins of Spain : the stratigraphic record of crusta] kinematics / edited by Peter F. Friend and Cristino J. Dabrio. p. cm. - (World and regional geology series) Includes bibliographical references. SBN 0 521 461715 1. Geology, Stratigraphic - Tertiary. 2. Geology, Structural­ Spain. 3. Basins ( Geology) -Spain. I. Friend, P.F. H. Dabrio, Cristino J. Ill. Series. QE69l .T465 1995 551.7'S'0946 - dc20 94-21724 CIP ISBN 0 521 46 l 7 l 5 hardback SE Contents List of contributors ix Preface P.F. FRIEND and c.]. DABRIO xiii Dedication 10 Professor Oria! Riba I Arderiu c. PUlGDEFABREGAS xv Memorial, Etienne Moissenet 1941-1994 P. ANAD6N, N. MOISSENET and O. RIBA PARTGGENERAL GI. Tertiary stages and ages, and some distinctive stratigraphic approaches P.F. FRiEND G2. Cenozoic latitudes, positions and topography of the Iberian Peninsula A.G. SMITH G3. Tertiary tectonic framework of the Iberian Peninsula C.M. SA NZ DE GAlDEANO G4. Deep crusta I expression of Tertiary basins in Spain E. BANDA GS. Oil and gas resources of the Tertiary basins of Spain F. MELENDEZ-HEvIAand E. ALVAREZ DE BUERGO G6. Mineral resources of the Tertiary deposits of Spain M.A. GARciA DEL CURA, C.l. DABRlO and S. ORD6NEZ PART E EAST El. Geological setting of the Tertiary basins of Northeast Spain P. ANA DON and E. ROCA E2. The lithosphere of the Valencia Trough: a brief review M. TORNE E3. 'Depositional sequences in the Gulf of Valencia Tertiary E4. ES. E6. E7. basin w. MARTiNEZ DEL OLMO Neogene basins in the Eastern Iberian Range P. ANAD6N and E. MOISSENET The Tertiary of the Iberian margin of me Ebro basin: sequence stratigraphy 1. VllLENA, G. PARDO, A. ptREZ, A. MUNOZ and A. GONZALEZ Tertiary of the Iberian margin of the Ebro basin: paleogeography and tectonic control J. VILLENA, G. PARDO, A. PEREZ, A. MUNOZ and A. GONZALEZ Stratigraphy of Paleogene deposits in the SE margin of the Catalan basin (St. Feliu de Codines-St. L1oren� del Munt sector, NE Ebro basin) 1. CAPDEVILA, E. MAESTRO-MAIDEU, E. REMACHA and J. SERRA ROW xvii 3 6 9 15 20 26 43 49 55 68 77 83 89 EB. Onshore Neogene record in NE Spain: Valles-Penedes and El Camp half-grabens (NW Mediterranean) L. CABRERA and F. CALVET E9. The Paieogene basin of the Eastern Pyrenees ].M. COSTA, E. MAESTRO-MAIDEuand CH. BETZLER EIO. The Neogene Cerdanya and Seu d'UrgeU intramontane basins (Eastern Pyrenees) E. ROCA Ell. Eocene-Oligocene thrusting and basin configuration in the 97 106 114 eastern and central Pyrenees (Spain) 120 J. VERGES and D. w. BURBANK E12. The Late Eocene -Early Oligocene deposits of the NE Ebro basin, west of the Segre River 134 E. MAESTRO-MAlDEU and 1. SERRA ROIG Eil. Chronology of Eocene foreland basin evolution along the weslern oblique margin of the South-Central Pyrenees 144 P. 8ENTHAMand D.W. BURBANK E14. Evolution of the Jaca piggyback basin and emergence of the External Sierra, southern Pyrenees 153 P.l. HOGANand D.W. BUR BANK EIS. Long-lived fluvial palaeovalleys sited on structural lineaments in the Tertiary of the Spanish Pyrenees 161 S.l. ViNCENT and T. ELLIOTT E16. Evolution of the central part of the northern Ebro basin margin, as indicated by its Tertiary fluvial sedimentary infill P.F. FRIEND, M.J. LLOYD, R. MCELROV, J. TURNER, A. VAN GELDER and S.l. VINCENT Et7. The Rioja Area (westernmost Ebro basin): a ramp valley with neighbouring piggybacks M.l. JURADO and o. RIBA PART W WEST W I. The Duero Basin: a general overview 1.1. SANTISTEBAN, R. MEDIA VILLA, A. MART1N-SERRANO and C.l. DABRlO 166 173 183 . W2. Alpine tectonic framework of south-western Duero basin 1.1. SANTISTEBAN, R. MEDIAvILLAand A. MARTiN­ SERRANO 188 vii W3. South-western Duero and Ciudad Rodrigo basins: infill and dissection of a Tertiary basin 1.1. SANTlSTEBAN, A. MARTiN-SERRANO, R. MEDIAVILLA and c.J. DABRIO W4. Teetono-sedimentary evolution of the Ajmazan basin, NE Spain 1. BOND 196 203 Vlll W5. Tertiary basins and Alpine tectonics in the Cantabrian Mountains (NW Spain) J.L. ALONSO, l.A. PULGAR, J.C. GARciA-RAMOS and P. BARBA W6. Lacustrine Neogene systems of the Duero Basin: evolution and controls R. MEDIAVILLA, C.l. DABRlO, A. MARTIN-sERRANoand l.l. SANTISTEBAN W7. North-western Cainozoic record: present knowledge and the correlation problem A. MARTiN-SERRANO, R. MEDIA VILLA and J.I. SANTISTEBAN W8. Onshore Cenozoic strike-slip basins in NW Spain L. CABRERA, B. FERRUS, A. SAEZ, P.F. SANTANACH and J. BACELAR W9. Tertiary of Central System basins A. MARTiN-SERRANO, 1.1. SANTISTEBAN and R. MEDIA VILLA PART C CENTRE Cl. Structure and Tertiary evolution of the Madrid basin G. DE VICENTE, J. M. OONZALEZ-CASADO, A. MUNOZ­ MARTiN, 1. GINER and M.A. RODRIGUEZ-PAscuA C2. Neogene tectono-sedimentary review of the Madrid basin G. DE VICENTE, l.P. CALVO and A. MUNOZ-MARTIN C3. Sedimentary evolution of lake systems through the Miocene of the Madrid Basin: paleoclimatic and paleohydrological constraints J.P. CALVO, A.M. ALONSO ZARZA, M.A. GARciA DEL CURA, S. ORDONEZ, l.P. RODRlouEz-ARANDA and M.E. SANZ-MONTERO C4. Paleomorphologic features of an intra-Vallesian paleokarst, Tertiary Madrid Basin: significance of paleokarstic surfaces in continental basin analysis 1.C. CANAVERAS, 1.P. CALVO, M. Hoyosand S. ORD6NEZ C5. Tectono-sedimentary analysis of the Loranca Basin (Upper Oligocene-Miocene, Central Spain): a 'non-sequenced' foreland basin 1.1. 06MEZ FERNANDEZ, M. DiAZ MOLINA and A. LENDiNEZ C6. Paleoecology and paleoclimatology of micromammal faunas from Upper Oligocene - Lower Miocene sediments in the Loranca Basin, Province of Cuenca, Spain R. DAAMS, M.A. ALVAREZ SIERRA, A.J. VAN DER MEULEN and P. PELAEZ-CAMPOMANES C7. Fluvial fans of the Loranca Basin, Late Oligocene - Early Miocene, central Spain M. DiAZ-MoLINAand A. TORTOSA Contents C8. Saline deposits associated with fluvial fans. Late Oligocene - 214 Early Miocene, LOTanca Basin, Central Spain 1. ARRIBAS and M. DIAZ-MOLINA e9. Shallow carbonate lacustrine depositional controls during the Late Oligocene -Early Miocene in the Loranca Basin 228 (Cuenca Province, central Spain) 237 M.E. ARRIBAS, R. MAsand M. DiAZ-MOLlNA PART S SOUTH SI. The Betic Neogene basins: introduction 247 CH. MONTENAT 255 263 268 272 278 285 295 300 S2. Neogene palaeogeography of the Betic Cordillera: an attempt at reconstruction C.M. SANZ DE GALDEANO and 1. RODRiGUEZ­ FERNANDEZ S3. Depositional model of the Guadalquivir - Gulf of Cadiz Tertiary basin c. RIAZA and w. MARTINEZ DEL OLMO S4. Late Neogene depositional sequences in the foreland basin of GuadaJquivir (SW Spain) F.l. SIERRO, LA. GONZALEZ DELOADO, C.l. DABRIO, J.A. FLORES and J. CIYIS SS. Miocene basins of the eastern Prebetic Zone: some tectono­ sedimentary aspects CH. MONTENAT, P. OTT D'ESTEVOU and L. PIERSON D' AUTREY S6. Stratigraphic architecture of the Neogene basins in the central sector of the Betic Cordillera (Spain): tectonic control and base-level changes 1. FERNANDEZ, 1. SORIA and c. VISERAS S7. Pliocene-Pleistocene continental infiUing of the Granada and Guadix basins (Betic Cordillera, Spain): the influence of allocyclic and autocyc1ic processes on the resultant stratigraphic organization J. FERNANDEZ, C. VISERAS and 1. SORIA S8. Late Neogene basins evolving in the Eastern Betic transcurrent fault zone: an illustrated review CH. MONTENAT and P. OTT D'ESTEVOU S9. Tectonic signals in the Messinian stratigraphy of the Sorbas basin (Almeria, SE Spain) J.M. MARTIN and 1.C. BRAGA StO. Basinwide interpretation of seismic data in the Albonin Sea c. DOCHERTY and E. BANDA Index 308 313 321 323 330 339 346 353 366 372 387 392 399 W2 Alpine tectonic framework of south-western Duero basin J.1. SANTlSTEIJAN. R. MEDIA VILLA AND A. MARTiN-SER RANO AbsCnl\:1 The teclonic activity in the south-western area of the Spanish Nonhern Mcsela (Ciudad Rodrigo ilnd Ducro basins) during most of Ihe Tertiary was determined by u Iransprcssivc regime that reactivated Hercynian 10 Llllc·Hcrcyruan faults. The record of the Alpine Orogcny is complex because the sedimenTary record indicat!."S 1I (, .. omprcs�ive regime in tbe source areas coeval with tlu: cxtcnsionallO Irdnspressl\'c regime indicated by normal or strike-slip faultlt. This duality is due 10 the geotectonk position of Ihis area between IWO compressive areas. the CUllIabrian Range and the Central System. and the c;o:;tcnsional Atlantic margin. Inlroouclion The Duero basin is an intmcolltiucntal basin of cratoOlc type (St'I1$1I Sloss & Spt:�. 1974) bounded by mountain range� that evolved relatively im.kpcndently during the Teni:lrY (Fig. I). Thc northern border is the Cantahrian Mountains. made up of Mesozoie and l'a!acoz01e rocks affected by thrusts and low-::II1Klc rcvcr�c rault�. [t� history is related to the Alpine evolution of thc Pyrenees. The eastern border is tbe Iberian RanKe that extends between the Pyrenc:es and Ihe Belies. the main Spanish compressive orogens. The southern border is the Centra! System, bounded by high­ unglc reverse and stnke-shp f;tults ofHercynian to Late Herqniull IlKC. reactivated during Alpine Orogeny. The western horder is the PU!(Jcolook metasedimentary and igneous rock.s of the western SPilllish Mt."SCta. It has a rel,nively passive tectonic history but was ,Iffccted by the evolution or the Atlantic: marKin. SQulh-Wl'st"", bnn/('r The south-west corner of the Duero basin is at the junction of two t�tonic(ll1y dilTcrI.:nt borders: one domin:tted by rewrS/: auu strikt. ... slip faults (the soutbern edge). and the other dQlllinatl.-d by vertical, low-magnitude movementS (the westefll border). The morphological expression of tin: jUllction area is a half-graben oriented NE-SW. and filled witb PaleogeJ}c and Nco­ gene sedimc:nts: it is referred to as the Cilldad Ru(lrigo GrulHlI fFosa de Ciudad Rodrigo'). The 'classic' relative chronology or alpine mo"emen1.� is based upon the assumption that the slratiKrllphie frameworks of the lJuero and Ciudad Rodrigo basins arc different. As a consequence, many authors consider that the palaeogeographic and tectonic evohltion of these two basins was indepenc1enl (Jimenez ('I a/ .. 1983: Corrochano & Carballclra, lYt!3). Howe\·cr. detailed mapping by the present authors has rc\'ealcd similar succes.�ions of Tertiary mnterials ill the Ducro and Ciudad Roorigo basins (Fig. 2). This implies Ihllt they were connected dunng the Tertiary and underwent a common evol Ulion (S,ltlliste­ han N al .. 1991: sce also Chapter W3). The Alpine teclonic.� Sauthn" bord", The southc:rl1 bvrder of tbe basin can be divided into two structural domains with different tectonic behaviour during the Alpine Orogeny: the Central System and a �ries of structures that will be refelTCd to as The norder Massifs (Fig. 3). Till! Ct't/lral SYS/('I/I The evolution orthe Central System bas been explained In several ways: rclalt.-d to an intracontinenta! �hear zone (Vegas rllll .. 1986). a:i a rhombus-grabcn (Pnrtero & Aznar. 19S4). and related to thrust nappcs or reverse faults (Warburton & Alvare:t.. 1989; Babin el Ill .. 1992: Vicenle er (11 .• 1992). Diverse stages ha\';: been estab­ hshed for the Alpine Orogeny in the northern IInd southern margins o('tbe Central System (Portero & Aznar. 1984; Vegas PI a/ .• 19)56; Capote ef (If., 1990;COllvo('tai .. 1991: Vicentc n aI., !992)(Fig.3). Capote el tll. (1 990) differentiated three faulting episodes or stages, and this is the most generally accepted division: ItKrian Stage: Mean horizontal compression N45-55E that ended with an almost rudial dislension with thc same axis orientation. The "KC coincides with lhe 188 W2 Alpine tcctonic framework of SW Duero uasin IRQ .. ' '" " " " " 0' " " <> n' ,� c::/" " '" '" ,.. (A) ,.' " " " " 0' " '" g � 3 � 5 A .',' . , ' . . . ' . . .. .. p . . . . . ' . - - . .... '. . . . . . . . . �· .B: . ' So .. : . . ' . . • • • • , • • • G:l 0 � . <$" � • 2 4 6 ' . . : .. • (8) FI�. I. A. Locadoll mal'OrOUtro Ruin In tll� Ihforian Prni'lSI.la: I: Ciud.ul RoxIrigu B.sin. Z: Almuim Hasin. 3: La Durtba Corridor. 8. Stud) Itru in UIH.·,u Ibsin: L: UOn. 8: 8urROS. P: I'lIltncia, So: Soria, Z: 7.amora. S: s..t3m�'1<:a: t: AI<'nl<'ju-Plltscncilt Fault. A: Cantabriu R�t, 0: Iberi311 Ra,,�e, C: O:nt"d S}'stl'm.U: W('$I('m ijordl'r. io;: Ciudad Rodrigo Basin. Kt},: PaleozoK:. I: mtlamflrphic rocks; Z: ilo;lM. ... "s rucks: I\ll'Wtok. J: carbonall!llllnd �i1i('kllsti<'l>: Cninolok. 4: �akkINSlil"S. carbonaln and c'aporllts: t-·aulls. 5: Inl·ttse faull: 6: norm al faull. Fill_ 2. TI',tilt'y units ofS\\' D�ro O��in, F'o!'''il�, 0: Absolute ale (Kr/Ar) 58 Ma (BI •• M. ... I'I uf., 1982). I: Sanlolf!' and "�edillo (Znmur.). Z: T�'SU de la Flfthll (Salamlnca) and CurrMI� 11 (Z.amora). 3: Molino de Pieo and Sltll MO'llt� (S.lamll1<:I). 4: C�l1IillO FlK'lIt� and io;l i\lolino (Cindnd Rodrigu BMsin), 5: El Guijo (SlIllInlanc.). 6: Rt-nan.'nt<· (Zamora). (Modified from SOInlislcbMD et al •• 1991.) Oligocenc-Early Mioccne boundary. but movements affected Paleogen� scdimellU'lliOll more gcnerally, GU.lldarrama Srage: Maximulll hurizontal compre.\sion N 1 40- 1 55E Ihal diminished with time. II look piaet' in Ihe Early Late Mior.:enc bound.'1ry (intra-Aragonian $efl,�r, Sinew) and was responsible ror the present n:vcfliC horst-grahen �t TtletuTe. Torrclaguna �Iage: This was a minor phase with compres· SlOn NI fIO-2oo!!. probably relate-cl lu the prevIOus onc. Lale Mioccne 10 Quaternary. The dall":> or Ihese �t!lgcs were deduced from Ihe sediments of the doses\ basins IIffcctcd by the fauhing. This r:1ises SOIlIC doubt .... p.nlil:ulltrly about the northern border or the G:ntral System, because there IS controversy concerning Ihe age of sedlmcnts affected hy the reverse faults of the Guadarrama Stage. Some authors (Corrales. 1982: Portero et (1/., 1982: Corrochano "/ "I.. 1983) consider these sedlments as Early-Latc Mioccne. whereas others (Olmo & Martinel·Salanova. 1989: Sunlislcban n 01.. 1991 : see Chapter W3) consider thcm :"tsOligOl.'l:nc in ugc (Fig. 2). The laSl dating implies llt:H Ihe lberiun Slugc was prc-Ohgoccne (rossih1y;\1 the Eoccne-Oligmocne boundary. I.C. thc I'yrene:m phase of Brink­ moruIII, 1931) and the Guadarrama Stage was Oligocene Early Mioccnc (the Saavic phase of Urinkmann, 1931). 190 J,1. Sanlis\cnan 1'1 (/1. !TITI 1 fill' 1'9' Cl- D' • ---(\: [T--- -- , --- . -- FlJ::. J. rrrl'loo� Intttprtlalillm of the Sfru"l"r.1 dr"l'lopn�nI of Ihl' Cwlral System. TIlt upper dlal,:filltl MowlI lhot loullnn Illtlle main I,:ttllOf,ic Wile!!; I - Border Massif$, 2 - Ira�,KlIl16nt . .1- CeRlral System ( ........... ucro basin have survi"N (Fig. 3), The structure ufthl:SC rml�sifs is quite different from the Centrul Sy�tem St'II.fII.uricto. They arc bounded hy normal or .!itTlke-slip f:tults with domi· nantly vCrlical mo\'ements :tnd a configuration of horsls and grabcns thatcxtends NE SW. Thl..'SC fault-bloc.:ks were horizontally displal.. .... -d by faults trending NNE-SSW and they are also bounded by WNW-F_'m faull� (Fig. 4). The border massifs preserve the bo:st r«ord ofthc alpine defor· tnation of Ihis an:u (Jimcncl. 1972: Jimcncz, 197:1; ("orrochano l'1 � I! FI(!..4. Falllting !ikrtrh nf WelHJI OuHo Rasin Hd� rrolll tic-Id .'orl; and ttltdtte<:linaMlidia 7.: Zanmn. F: FlNn_UI!, S: Salam..-,ca, CR: CilHlad Rodril:o. G: GuijllHo. (.'rnm Santisttbln�' .1 .. in pl"ts5.) tll .• 1983). (Figs. 5 and 6i\). Accordingly 10 Brinkmunn's (1931) nOlllcndature the 11..'Clonic stages of thIS area are: - Laramicphasc(lateCretaceous Palcoccllc): faulting of basement affected by the McsolOie lateritie weathering profile. - Neo-Lj;t in rchuion lu NNE.-SSW rHulls. - Saavic phase (01igocene-E�rly Miocene): movements of NE SW llnd E-W normtll f:ll1l1s that modified the basin cxtcn:;ion and lilti:d previously defined blocks. NNE-SSW faults lowered hlex.:ks towards th\: 1\I\:Sl. Major uplift in the e:lstern and soulh-c:lstern :treas gcm:rlltt:<1 (I configuration vcry close to thc present. Staine phase (Early-Late Mi(x:cne. PliOl.'Cne); sllIall extensional phenomena Ih:u lowered hlocks towards the west. This border has Ix:cn considered inactive due 10 the scarcity or Terli:uy deposits allowing the recognition of alpinc movements. and the fragmentation orlhe old. pl:tin landscape. However. detailed study of small Tertiary sediment3ry OUlcrops and weathering profiles has revealed at least three tectonic stages of post-Palcoccm:. prc.Oligoccne and post·Oligm.'Cl1e ages. Relaled vertical displaccmenls arc about 100111 (Figs . 5 :Ind 611). The first faulting stage affected igneous �lIld mctamol'phic rocks with a sup:.;rimposcd laleritie weathering profile and silicificalion proce.�ses or Meso7.0lc age. related 10 Ihe lOp or MC tcctonosedi­ menlary unil (MCTSU of Fig. 6). (Upper Cretaceous Paleoccne ) . EIS\:whcrc. thl.�e fuults arc fossilisl.,j by tlw sedimenls of the PI TSU (Lower Eocene); rault movements can hcdated as i'aleocene-E.1rly Eocene. However. it may be argued thal this is actually the result or a double raulting process (pre-Paleocene and PaJl'Ol.,\:lIl.'-Eurly EOI.."Cne). Scdiments or the younger "3 TSU (Oligoccne) 3re located in topographicnlly lowcr positions 10 the west of the previous units ou\: to NNE-SSW and NE-SW fault systems. Thcse strltl:tUrcS extend to the Valderaduey raultlllg ?one (Ma rl;n-Scrrano, 19t!t!). Igneous rocks often show S-C structures. related to these move­ ments. tlmt rC('ord nOTluul displm.:ements (Die/. Monh:s. IJI.:rs. commun .. 1992). The distrihution of scdiments or the 1'3 TSll rel ated 10 these r:.lulls. and the displacement orr:lults by other 1:1ult systems show that these movements are of pre·Oligocellc ugc. The last tectonic movements r�'Corded here lowered hlock� lIlelllding Ter1iary sediments 10wards the west. i.e. away from Valderaducy fracture ZOIle:". Two stilges e(in be differentiated: a first subsideuI.'C of the �edirncllts of Pl TSU towards lIw cust. followed by rotation (Iilting) of hlnck.� and suhsidence to the west. A minimllm age cannot so rar he given to these mOI'e:"n1e:"llts bccauscof the absellce of younger deposits. They an: thought to be of post­ OligOl..'Cne age. The Cill(/u(/ R(x/rigu Busill This is a half-grahen hounded 10 thesollth hya m:lIn NE­ SW fault. In fact, t his is not a single rault but a parallel system cut by a conjugate (secondary) NNE-SSW systellltilat disphll.:�� the main system. There are also searce NW SE and WNW ESE faults that displa�-c the fault (Figs. 5. 7A and 7B). Thc hasin horder therefore ha� a complex �trllctllrar history. The high·angle dip of the fault planes makes it very difficult to dt:terrnim: tb,· true l..:ompollents of l11ovenwnt. Grudll Plalll et al. (19RI) and Jimcne7. & Martin-I?�1rd (1'>11<7) deserihed mike-shp components. whereas Alonso G:lVilan & Polo (1986 87) found normal components, The aeeullluluto.:d vertil;ul displlleC!l1\:llt amounts 10 300 m (limenez & Martin-l7.ard, 1987). No reverse components have been found so t;,r. The first Alpine movements in the Ciudad Rodrigo Basill. suppo�,j to be of the Laramie phuse. caused domes trending NE­ sw (Mingarro 1'/ (11 .. 1'>170). I l owever, alpine t:lltlting hcrore the Eocene cannot be clearly identified due 10 the lack of previous sediments . ThcCiudad Rodrigo Hasrn was generated In the I:-:arly Eocene hy the activity of the rault fonning the southern boundary. At the Eoccne Qligoccne transition. ni:W rellctivatiulI of faults 192 1.1. Sanlisleban et al. N s A' sw NE " lZ3""_Gauoo/WI str;("fO �hC)w lealures that indieall;" a close rclalion�hip between tectonics and sedimentation. Thc� fentures arc fractures and anomalous thickncs5l.'S of scdiment� related to buried fault systems (Figs. 5 and GAl. Upper Cretaceous to Paleocc(le sedimenlation took place in :l low-relief lalldscuPl' with irregular topography and a wdl·dcvel­ oped weathering profile. i\ younger episode 01' faulling broke up this llomogeneou.� pattern. This is oh�erved only in the margins of thc ha�in. During Early-Middle Eoccne times. the basin IIlted towilrds the cast and norln-east. Although the surface e�pres5ion of the faults wa� not strong. there were nOlable differences of subsidence related 10 deep faults. I n the trhysical datu show a erustal thickening in Ihe Central System and thinning towards the north-west (Martin Escor7 .. 1 . 1990; Babin N 01 .• 1992). However. these arc Ill(."rdy hypotheses and thcy now need to he lestr..-d by new sludic.�. COIK:lusiUII 'rhe SOl1l h-western area of tbe Spanish Northcrn Meseta (Ciudad Rodrigo and Ouero basins) is charactcri:;ed by tr..�tonically 194 J.1. SlIntisleb.1n ('( (11. active south and south-western boundaries and " rdallvdy tecloni­ cally pas!m'c ..... e..'lIcrn horder The tectonic activity in the area during most of the Tertiary was dClermin«i by 3. transpressive regime that reactivated Hi.:n:ynian tu Late-Hercynian faults. newly created faults tin: scan .. 'C. The: mum fauitio)! SIUgl':; hltv\! slrikl.-....slip 10 nonnal components. Unllle response of the lTusllIol materials favoured faulllng Instead of folding. However, wdlmentary unllS show a co.1r�ning-upwards trend related tn acceler.ued uphO oflhe source areas located to the south and SOUth·C3St. This cvidcoce indicates n compressi ve regime for areas located towards the cast (Cenlful Syslcru) during Pal<:o­ gene til11l,.'$. Nl'OgCUC dcpo�ition m:ords cxtcnsional regimes. The [1,.'Clonic activity 5tronllly ehanged the morphology and boundnrics of Ihls Area genwtttng and modifying sy�tems ofhorsts and grahcn�. There i� a complex rCCQrd of the Alpine Orogeny in the arca. bcc,1Ust the sedimelllary record indicates a comprcssivc regim.-: in Ibe SOIlrct: areAS, coeval with an extellsioll,,1 to 1["'.ul�pn:�sivc regime indio..-alt:d by nomllll or strik!.--shp fault�. This dualilY IS due 10 I he gcotcclonil.: position of thill llrea bel ..... een IWO comprrt,;ve areas. the Cantahnao Ibnge and Ihe Central Syslem. and the extensional AII:mtic margin. Tbe 5Oulh·w�tern nuero 8..1sin is considered 10 ha\'c bl"'Cn a moderately active area of crotonic type (.reMit Sloss & SIX-"'Cd. 1974). It occupies an intermediate position �lween the largest areas of deformation of lhe Iberian Plate. Referenct'.41 AlollsuGa,·ilii.n. 0.11981 I. E-mllugralia 'J sedlmentolosia del Palco�no en cl horde .�Llrocddental de la Cuenl."lI del Dwro (I'rovlnela de !\3�m."lell) PhD Thesis. Salamanca Univ.: 435 pp. Alunso (Jltvtl'n. v. and Cantllno. M. (19117). u F()rm:,cion Arewscas de Ciudltd Rodngo: cJcmplo de �dimenlaeiim ennlrol:tda por p.lleorr ... lie .... 'S (EUl'O!IIU. rosa de CIUdlld RodnI!O). S/I·d. Grol. SalmU"II'"l'tl.lI". 24. 247 258. Alonso Gavil.ln. G. &.: Poln. M.A (19I1f,....jj71. EvoJucioll 1�'"Cto-�dlJlJeIIIUl"la ohgomioci:nicll del SOde la fo�, deCiurlad Roorigo. Sal;!lIIilllc". A("/(I (Jet,f. I/iJp .• 21-22: 419-426. R.1bin. R , !kri"min, J.F., Fcm;mdez Rodnsucl, C . • Gonrilez COIsado. lM .• HenHinde� Emile, J L. R,i'·II'. A . TCJcro. R. and vkcnu:. G, de (1992). MooetM gntvitMlrico:s 1>3ro III cork:.a< supo:riur �'1l cl borde SE del Si�temOl Cenlral E.\p-1Iiol GM1:"C('I.tellla Celllrul Eiipatiol (S.C.E.). CiroguWQ. 7: 20-22. Comdcs. I. (I')1I2). t;1 Mlot'rno al sur del rlo Duem (s.ector occirienlat). f &.,,,"';,, Johrl' lu GrolUfIiu ,� la Cr.ert<"o tkf fJutro. Saluma/rea 1979. r"""'J c.-ul. MIMruf . 6: 709 713. Corrochano. A. (1977). E.slraligrnfi.1 'J r.alimenrologia dd Pa�.,nu,Je Ilt, provtncia de lamOnt. PhD. Thesis, s..'!:lm:mc:> Univ . 336 pp. UnpubhJhcd. O;orrochano. A. anu C"rballcir�. J. (1')113). Las depresl0nel del borde �uroccidenlnl 11.: I" CUelll:M uel DueTU. In J.A Comba (cd. I. Libro JublJur i.M. Rim. TWill, If. (,<'(Ifr>giatk E.Jpmill. 5 1 3 521. IOM E. Madrid. COfl"OcllillIU, A., Catbu!lclry. 1 .. 1'01. <.;. �nd c.:orrales. J. (1983). Lo� sislemas dl'l)usiciulIlIl..s kn:H.lrio� �k In dcpICslon de Petiaranda .. Alh ("lL'm'j. M:lpa y Memonu expilcatlll1l: 12 pp. IGME. Madrid. Moreno. r. (1991) SlIpcrlicies dc erosion 'J tectoniC:d II<.-Qgcml en et elltemo occidtntal dd Si�telll� Ce1l11"al F.s""iiol GrogalYla. ,: 47-50. Ulmo, A. del and Martlnc7 ... Salanova, 1. (1989). El 1r:insilO Cretacico rcm.no en la SIC.'ITa de GU3darr.una y irea� pro,xim�$ de las r.ut)lca$dd Dueru 'JT IIIJo. ln C.l. Uabno(cd.). PQftOf{M$!.fI1jiu@ 11' M!'St.'tu ,vlJflrJ"runlr rf Ttrdllrw, Slvd. Grol. Sa[mUlllfct'fl.lia. \'01. 5: S5-#}. Purkru. J.M. and Aznar.J.M. ( 19&4). [vnlucion morfuleclonica ykIJu'lell" laaOlI en el Sistt'11lll ('enlllll ycuc-ncas limilrofa (Duero y Tajo). I CUlIJ(' E.l GI:"t>f .• 3: 253-263. Portero. J.M .. OlulO. P . ..k:1. RlI",ire� del Po�o. 1 and Vatgas. 1. (1982). SinlUIS del Tercillrin continental de I:l Cuelle" uel OUI:ro. I Rtrml6n sobrl' fQ Gf()lvgi� tit la Cwtffl"U J..I DlIl'rll, SlIfum(mrn 1979. /1.'fOIlD GtoI. MUlfral., 6: 1 1-37. Procnc;a Clluha, P.M R.R. IIm) Pen" dos Rei', R.P.D. ( 1 992). Sin leSt da evolu�ao gendin:imic;, e p.1leogeugnifK"1.I uo S(.'Clor nOTlC da Hllel;! LI.l�itanica. dumnle n Cre!3cicQ c Ten·i;'mu. III CaIlK" (iMf. t:spmiuy VI/I «mxr. /.alinoaml'f. iI(' (if'flf .. ACI3$, I' )07 1 1 2 W2 Alpine tectonic framework of SW Ouero b:lsin 195 Salllisteban. J.I.. Murtin-S<:rruno, A. unu Mcdi