175 Revista de la Asociación Geológica Argentina 75 (2): 175-187 (2018)

Toward a multidisciplinary chronostratigraphic calibration of the - transition in the Neuquén Basin

Diego A. KIETZMANN1, María Paula IGLESIA LLANOS1, Daría K. IVANOVA2, Melisa KOHAN MARTÍNEZ1, and Magalí A. STURLESI1

1Instituto de Geociencias Básicas, Ambientales y Aplicadas, Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Uni- versidad de Buenos Aires - Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires Email: [email protected]; mpigle- [email protected]; [email protected] [email protected] 2Department of Paleontology, Stratigraphy and Sedimentology, Geological Institute, Bulgarian Academy of Sciences, Sofia, Bulgaria. Email: dariaiv@ geology.bas.bg

ABSTRACT

Detailed systematic studies have been carried out in the Formation in order to achieve an integrated multidisciplinary calibration of the Jurassic/Cretaceous transition in the Neuquén Basin. Although this unit has a very well-established ammonite , the temporal distribution of biozones is yet a matter of hot debate. In this contribution we present the results of a well constrained integrated data from the Arroyo Loncoche section (southern Mendoza), where comprehensive cyclostratigraphic, paleomagnetic and biostratigraphic sampling/data allowed us to elaborate a very strong chronostratigraphic scheme for the Titho- nian- interval. The proposed stratigraphic calibration of the -Berriasian Andean succession brings foward two key points: 1) The base of the Vaca Muerta Formation shows a polarities pattern which would only be compatible to the uppermost part of Hybonotum Zone (lowermost Lower Tithonian). 2) The position of the Jurassic - Cretaceous boundary is located within the lower third of the S. koeneni Zone.

Keywords: Vaca Muerta Formation, Tithonian, Berriasian, chronostratigraphy

RESUMEN

Calibración estratigráfica multidisciplinaria de la transición Jurásico-Cretácico en la Cuenca Neuquina Se realizaron estudios sistemáticos de detalle en la Formación Vaca Muerta con el fin de lograr una calibración multidisciplinaria integrada de la transición jurásico/cretácica en la Cuenca Neuquina. Aunque esta unidad se caracteriza por presentar una bioestra- tigrafía basada en amonites, la distribución temporal de las biozonas es todavía un tema de importante debate. En esta contribución se presentan los resultados integrados de la sección Arroyo Loncoche (sur de Mendoza), en donde exhaustivos estudios cicloestra- tigráficos, paleomagnéticos y bioestratigráficos han permitido elaborar un robusto esquema de correlación cronoestratigráfico para el intervalo Tithoniano-Berriasiano. La calibración estratigráfica propuesta para la sucesión tithoniano-berriasiana andina presenta dos puntos clave: 1) La base de la Formación Vaca Muerta muestra un patrón de polaridades que solo sería compatible con la parte superior de la Zona de Hybonotum (Tithoniano Inferior bajo). 2) La posición del límite Jurásico - Cretáceo está ubicada dentro del tercio inferior de la Zona de S. koeneni.

Palabras clave: Formación Vaca Muerta, Tithoniano, Berriasiano, cronoestratigrafía

INTRODUCTION marlstones, and limestones deposited as important oil and gas resources, as well result of a rapid and widespread Paleo-Pa- as its abundant fossil content and tempo- The Vaca Muerta Formation is a thick rhyth- cific Early Tithonian marine transgression ral continuity along several hundred me- mic alternation of dark bituminous shales, in the Neuquén Basin. It is famous for its ters of section that comprise the Jurassic/ Jurassic-Cretaceous transition in the Neuquén Basin 176

Cretaceous boundary (Leanza and Hugo proximately equivalent to the base of the biagi et al. 2008). 2) Thermal subsidence 1977, Legarreta and Uliana 1991, Uliana Zone and correlated with the with local tectonic events established in the y Legarreta 1993, Desjardins et al. 2016). upper part of M19n.2n Subchron. 3) The Early Jurassic - Late Cretaceous was char- Jurassic-Cretaceous Andean biostratigra- last definition corresponds to the base of acterized by regional deposition of ma- phy is well defined by ammonites (Leanza the Occitanica ammonite Zone, correlat- rine sequences, included in the Mendoza and Hugo 1977, Riccardi 2008, 2015) and ed with the middle part of the Calpionella Group. The Vaca Muerta Formation (Early to a lesser extent, by (Ballent Zone and the lower part of M17r Subchron Tithonian - Early ) represents et al. 2011). Andean ammonite zones are (Hoedemaeker 1990). Recently, the Berri- the most distal deposits (e.g., Legarreta essentially based on the works of Lean- asian Working Group of the International and Uliana 1991). 3) A compressive defor- za (1945) and Leanza (1980), with minor Commission on Stratigraphy has defined mation regime was established during the modifications. Such zones have high bio- the Jurassic/Cretaceous boundary at the Late Cretaceous, and continued through- stratigraphic resolution, even though their base of the Calpionella Zone in the middle out the Cenozoic, although alternating with autochthony prevents a straightforward part of M19n.2n Subchron (e.g. Ogg et al. extensional events (Ramos and Folguera correlation with the Tethys and prompts 2016, Wimbledon 2017). 2005, Ramos 2010). This Andean defor- the occurrence of different correlation In addition to this global problem, absolute mation resulted in the development of a schemes between Andean and Tethyan ages coming from the Neuquén Basin are series of N-S-oriented fold and thrust belts ammonite Zones (e.g. Leanza 1980, 1996, non-consistent with those of the geologi- (Aconcagua, Malargüe and Agrio fold and Riccardi 2008, 2015, Vennari et al. 2014). cal time scales (Ogg and Hinnov 2012, thrust belts) where extensive outcrops of The study of microfossils has advanced Ogg et al. 2016). A TIMS age of ~139.5 the Mesozoic successions are exposed. considerably since the first synthesis Ma for the middle part of the Argentinic- In the southern Mendoza area of the works of Musacchio (1978). An extremely eras noduliferum ammonite Zone obtained Neuquén Basin, the Lower Mendoza Sub- detailed work that characterize the Juras- by Vennari et al. (2014) led these authors group (Leanza 2009) consists of aggrada- sic – Cretaceous microfossils from out- to suggest a difference of c. 5 Ma with the tional sequences, with a maximum thick- crops and subsurface sediments is found present geologic time scale, based on ness of 500 m towards the center of the in Ballent et al. (2011). Particularly, the oceanic basalts dating. basin (Legarreta and Gulisano 1989). It studies of calcareous nannofossils (Bown The aim of this work is to combine different includes continental deposits of the Tordil- and Ellison 1995, Scasso and Concheyro methods in order to improve the reliability lo Formation (Kimmeridgian-Early Titho- 1999, Bown and Concheyro 2004, Lesca- and accuracy of chronocorrelation in the Ti- nian?), basinal to middle carbonate ramp no and Concheyro 2009, 2014, Vennari et thonian–Berriasian of the Neuquén Basin, deposits of the Vaca Muerta Formation al. 2014), as well as other Tethyan calcar- using biostratigraphy (Kietzmann 2017, (Early Tithonian-Early Valanginian) and eous microfossils, such as calpionellids, Ivanova and Kietzmann 2017), cyclostra- middle to inner ramp oyster-deposits of the saccocomid microcrinoids and calcareous tigraphy (Kietzmann et al. 2011b, 2015) Chachao Formation (Early Valanginian), dinoflagellate cysts (Fernández Carmona and magnetostratigraphy (Iglesia Llanos which form a homoclinal carbonate ramp et al. 1996, Fernández Carmona and Ric- et al. 2017). We consider that the only way system (e.g. Carozzi et al. 1981, Mitchum cardi 1998, 1999, Kietzmann and Palma to resolve such discrepancies with abso- and Uliana 1985, Kietzmann et al. 2014). 2009, Kietzmann et al. 2011a, Kietzmann lute ages is in the first place, to build up In this work, a detailed stratigraphic anal- 2017, Ivanova and Kietzmann 2017). a refined chronostratigraphic scheme that ysis of the Arroyo Loncoche section is The remarkable increase of faunal provin- could allow a reliable correlation between presented. This corresponds to a classi- ciality, as well as the uncertainties in the the Andean and Tehyan realms. cal Jurassic-Cretaceous section from the inter-regional correlation constitutes a ma- Neuquén Basin, where the Lower Mendo- jor classic problem for the Tithonian-Ber- za Subgroup includes the Tordillo Forma- riasian across the world (e.g., Ogg and GEOLOGICAL SETTING tion (~150 m), the Vaca Muerta Formation Hinnov 2012). The definition of the base of (~280 m) and the Chachao Formation (~25 the Cretaceous System is still controver- The Neuquén Basin was a retro-arc basin m). The biostratigraphy has also been de- sial. Historically, at least three definitions developed in Mesozoic times along the Pa- rived from complementary outcrops (Tres are considered (Remane 1991, Wimble- cific margin of South America (Fig. 1). Dif- Esquinas in the Atuel depocenter, and Río don 2008, Grabowski 2011, Gradstein et ferent tectonic regimes exerted a first-order Seco de Tosca, and Río Seco del Altar in al. 2012): 1) one is the base of the Grandis control in basin development and sedimen- Sierra de la Cara Cura), as well as subsur- ammonite Zone defined in the Colloque tary evolution (Legarreta and Uliana 1991, face data (Fig. 1). sur la Crétacé inferieur (1963) that corre- 1996): 1) Extension was established during sponds to the lower part of the Calpionella Late -Early Jurassic, that prompted Zone, almost coinciding with the base of the formation of narrow, isolated depocen- METHODOLOGY M18r Subchron. 2) The second is the base tres controlled by large transcurrent fault of the Jacobi ammonite Zone, defined in the systems filled mainly with continental de- Several studies were carried out at the Colloque sur la limite Jurassique-Crétacé posits of the Precuyo Group (Manceda and Arroyo Loncoche section including facies (1973), which is often regarded as ap- Figueroa 1993, Vergani et al. 1995, Giam- analysis, and sequence stratigraphy (Ki- Jurassic-Cretaceous transition in the Neuquén Basin 177 etzmann et al. 2008, 2011b, 2014), cy- onellids. Ammonites come from 80 levels formation were studied under a petro- clostratigraphy, magnetostratigraphy (Ki- that restrain the deposition of the Vaca graphic microscope for taxonomic identifi- etzmann et al. 2015, Iglesia Llanos et al. Muerta Formation to the Early Tithonian cations of calcareous dinoflagellate cysts 2017) and calcareous biostra- – Late Berriasian (Virgatosphinctes ande- and calpionellids (Kietzmann 2017, Ivano- tigraphy (Kietzmann 2017, Ivanova and sensis to Spiticeras damesi Assemblage va and Kietzmann 2017). Kietzmann 2017). Zones; Leanza et al. 1977, Kietzmann et Cyclostratigraphic analysis is based on Biostratigraphy is based on ammonites, al. 2011b, 2014). In addition, a total of 85 the differentiation of dm-scale carbonate/ calcareous dinoflagellate cysts and calpi- thin-sections distributed along the whole siliciclastic lithofacies couplets or elemen-

Figure 1. a) Sketch map of the Neuquén Basin with detail of the mentioned localities; b) Stratigraphic chart for the Neuquén Basin; c) Lithostratigraphic subdivision of the Lower Mendoza Subgroup in Southern Mendoza. Ki: Kimmeridgian, Ti: Tithonian, Be: Berriasian, Va: Valanginian. Jurassic-Cretaceous transition in the Neuquén Basin 178 tary cycles, and bundles and superbundles Neuquén Basin reveal a relatively rich 1968): The base of this zone is defined at differentiated in the field. Lower frequen- micropaleontological assemblage of 24 the first occurrence (FO) of the species cies are searched using spectral analysis known species of calcareous dinoflagel- Parastomiosphaera malmica (Fig. 3b) and with the software POWGRAF2 (Pardo-Ig- late cysts, as well as levels with poor pre- its top at the FO of the species Colomis- úzquiza and Rodríguez-Tovar, 2004) using served 18 known species of calpionellids phaera tenuis. This zone corresponds to Blackman-Tukey method. For further ex- (Ivanova and Kietzmann 2017, Kietzmann the Early Tithonian (Ivanova in: Lakova et planation, see Kietzmann et al. (2015). 2017). Different bioevents of global impor- al. 1999, Reháková 2000a, b). In the Vaca Magnetostratigraphy derived from 56 sam- tance are recognized that allowed to dis- Muerta Formation, this zone is recognized pling horizons or sites with an average tinguish 6 calcareous dinoflagellate cyst in the upper part of the Virgatosphinctes site-distance of ~5 m. At each site, four zones and 2 calpionellid zones (Fig. 2). andesensis and Pseudolissoceras zitteli oriented cores were obtained using a por- Zones. table core drill, with at least two standard Calcareous dinoflagellate cysts Colomisphaera tenuis Zone (Řehánek specimens, making a total of 8 specimens Calcareous dinocysts are important strati- 1992): The FO of the index-species Colo- per site. Altogether, c. 450 specimens have graphic markers for the Upper Jurassic misphaera tenuis (Fig. 3c) marks the base been obtained and processed. Paleomag- - Lower Cretaceous time interval in the of this zone in the Tethyan region and cor- netic treatment and analysis of specimens Tethys. In the Vaca Muerta Formation, responds to the latest Early Tithonian (Iva- were performed using alternating fields (AF) Ivanova and Kietzmann (2017) report the nova in: Lakova et al. 1999). In the Vaca and high temperatures (TH) demagnetizing following dinocysts zones: Muerta Formation, this zone is recognized methods. The AF method was carried out Carpistomiosphaera tithonica Zone (Iva- for the moment within the Aulacosphinctes using a 2G demagnetizing device, whereas nova in: Lakova et al. 1999): The estab- proximus and Windhauseniceras interni- the TH with a Schoenstedt furnace. Resid- lishment of this zone is defined by the spinosum Zones. ual magnetizations were measured in a 2G presence of Committosphaera pulla (Fig. Colomisphaera fortis/Stomiosphaerina DC SQUID magnetometer (see Iglesia Lla- 3a), species that spans the Early Titho- proxima Zones (Řehánek 1992): In the nos et al. 2017 for more details). nian, and occurs in association with the Tethyan realm, these correspond to two index-species Carpistomiosphaera ti- separate zones, but in the present study, thonica. The C. tithonica Zone spans the it is not possible to separate one from CALCAREOUS Kimmeridgian-Tithonian boundary interval each other. The lower boundary of Colo- MICROFOSSIL (Ivanova in: Lakova et al. 1999, Reháková misphaera fortis Zone is defined by the BIOSTRATIGRAPHY 2000a, b). This zone is recognized in the FO of the index-species (Fig. 3d). The lower part of the Virgatosphinctes ande- Fortis Zone coincides with the upper part Detailed micropaleontological studies sensis Zone. of the calpionellids Praetintinopsella Zone in the southern Mendoza area of the Parastomiosphaera malmica Zone (Nowak and the lower Crassicollaria Zone (Late

Figure 2. Calcareous dinocysts index-species from the Vaca Muerta Formation: a) Committomiosphaera pulla (Borza); b) Parastomiosphaera malmica Nowak; c) Colomis- phaera tenuis (Nagy); d) Colomisphaera fortis Řehánek; e) Stomiosphaerina proxima Řehánek; f) Stomiosphaera wanneri Borza; g) Colomisphaera conferta Řehánek; h) Carpistomiosphaera valanginiana Borza. Jurassic-Cretaceous transition in the Neuquén Basin 179

Tithonian). The lower boundary of Stomi- its very top). In the Vaca Muerta Forma- coincides with the first occurrence of chi- osphaerina proxima Zone is defined by tion this zone is recognized from the upper tinoidellids in the Vaca Muerta Formation the FO of Stomiosphaerina proxima (Fig. part of the Argentiniceras noduliferum to at the middle part of the Virgatosphinctes 3e). The zone is a relatively long-ranging the upper part of Spiticeras damesi Zones. andesensis Zone. The upper boundary is from the latest Late Tithonian to the middle Colomisphaera conferta Zone (Ivanova in: defined by the FO of hyaline calpionellids Late Berriasian (Ivanova in: Lakova et al. Lakova et al. 1999): This zone is defined in the transition between the Windhau- 1999). In the Vaca Muerta Formation this as the interval between the FO of Colo- seniceras internispinosum and Corongo- zone is recognized for the moment from misphaera conferta and the FOs of Carp- ceras alternans Zones. This zone can be the lower part of the Corongoceras alter- istomiosphaera valanginiana (Fig. 3h) divided in two subzones. The lower one is nans to the upper part of the Argentinic- and/or Colomisphaera vogleri (Ivanova characterized by Borziella slovenica and eras noduliferum Zones. in: Lakova et al. 1999). The range of the Dobeniella cf. pinaraensis (Fig. 4a-b), typ- Stomiosphaera wanneri Zone (Ivanova in: zone is Late Berriasian - Early Valanginian ical components of the Longicollaria dobe- Lakova et al. 1999): This zone is defined (Grabowski et al. 2016). In the Vaca Muer- ni Subzone. The upper one, corresponds by the FO of the index-species Stomios- ta Formation this zone is recognized from to the Chitinoidella boneti Subzone, and phaera wanneri (Fig. 3f) at the base and the upper part of the Spiticeras damesi coincides approximately with the Wind- FO of Colomisphaera conferta at the top. to the lower part of the Neocomites wich- hauseniceras internispinosum Zone. It The Stomiosphaera wanneri Zone corre- manni Zones. contains Chitinoidella boneti, Ch. hegarati sponds to the latest Late Berriasian and and Ch. elongata (Fig. 4c-e). Early Valanginian (Ivanova in: Lakova et Calpionellids Crassicollaria Zone (Alleman et al. 1971): al. 1999). However, due to the correction The distribution of calpionellid species The base of this zone is represented by in the FO of the species Colomisphaera allows recognizing two of the calpionellid the FO Calpionellidae, including Tintin- conferta (Fig. 3g) in the uppermost Berria- standard zones: Chitinoidella and Crassi- nopsella carpthatica, Calpionella alpina, sian (Grabowski et al. 2016), Ivanova and collaria Zones. Crassicollaria intermedia, Cr. massutin- Kietzmann (2017) change the range of the Chitinoidella Zone (Enay and Geyssant iana, and some chitinoidellids (Fig. 4f-j). zone to the latest Late Berriasian (except 1975): The base of the Chitinoidella Zone It coincides approximately with the Coro-

Figure 3. Chitinoidellids and calpionellids from the Vaca Muerta Formation: a) Borziella slovenica (Borza); b) Dobeniella cf. pinaraensis (Furazola Bermudez and Kreisel); c) Chitinoidella boneti Doben; d) Chitinoidella hegarati Sallouhi, Boughdiri, and Cordey; e) Chitinoidella elongata Pop; f) Carpathella rumanica Pop; g) Crassicollaria intermedia (Durand-Delga); h) Crassicollaria massutiniana (Colom); i) Tintinnopsella carpathica (Murgeanu and Filipescu); j) Calpionella alpina Lorenz. Jurassic-Cretaceous transition in the Neuquén Basin 180 ngoceras alternans Zone, but its upper CYCLO- AND MAGNETO- to the base of Microcanthum Standard boundary has not been identified yet in STRATIGRAPHIC SCALES Zone). the Arroyo Loncoche section. In the sub- surface this boundary was identified by In order to anchor these scales to the Cyclostratigraphy the last occurrence of Calpionella ellip- geological time scale of the Interna- The Vaca Muerta Formation has decime- talpina at the upper part of the Corongo- tional Commission on Stratigraphy, we ter-scale rhythmicity, showing a well-or- ceras alternans Zone (Kietzmann 2013 in followed the criterion chosen in Kietz- dered hierarchy of cycles within the Mi- Gonzalez Tomassini et al. 2015), however, mann et al. (2015) that uses the base lankovitch frequency band (Scasso et al. the acme of C. alpina has not been recog- of the Windhauseni- ceras internispino- 2005, Kietzmann et al. 2011b, 2015). El- nized in the studied sections. sum Zone as primary datum (equivalent ementary cycles have a relatively regular

Figure 4. Summary of calcareous dinocyst and calpionellid events and zones identified so far in the southern Mendoza area of the Neuquén Basin (based in Kietzmann 2017 and Ivanova and Kietzmann 2017). Jurassic-Cretaceous transition in the Neuquén Basin 181 thickness in the order of 20 to 40 cm, so Regions, these polarities were calibrated The presence of the Carpistomiosphaera that they can be regarded as temporarily according to the last Geomagnetic Polar- tithonica calcareous dinoflagellate Zone equivalent units. Three types of elementa- ity Time Scale (GPTS) compiled by Ogg also supports this correlation (Lakova et ry cycles are recognized, which consists of and Hinnov (2012). Results show a good al. 1999, Reháková 2000). two hemicycles of similar thickness: lime- correlation between both magnetostrati- The Pseudolissoceras zittelli Zone shows stone/marlstone, marlstone/marlstone and graphic scales. a minimum duration of ~0.61 myr, and marlstone/shale (Kietzmann et al. 2011b, From base to top, the Virgatosphinctes spans the M22n to M21n Subchrons (up- 2015). Elementary cycles are grouped andesensis Zone comprises a set of re- per Darwini to lower Fallauxi Standard into sets of 4-5 elementary cycles (bun- verse, normal, reverse and normal po- Zones). This zone also contains calci- dles), and these are grouped into sets of larities, which we interpret to span the spheres of the Parastomiosphaera malmi- 4-5 bundles (superbundles). Such stack- M22r.2r to M22n Subchrons in the GPTS. ca calcareous dinoflagellate Zone, and in- ing pattern is used by different authors as The following Pseudolissoceras zitteli cludes the FO of Polycostella beckmannii diagnostic criteria to identify the influence Zone bears normal, reverse and normal (see Kietzmann et al. 2011b) which occur of orbital forcing (e.g., Goldhammer et polarities that would correspond to M22n at the upper M22n Subchron (Casellato al. 1990, Schwarzacher 1993, Anderson to the base of M21n Subchrons. Aulaco- 2010). 2004, Strasser et al. 2004). The 5:1 ratio sphinctes proximus Zone comprises a set The Aulacosphinctes proximus Zone (5 elementary cycles per bundles) is com- of normal and reverse polarities that are shows a minimum duration of ~0.61 myr, monly attributed to high frequency eccen- correlated with M21n to M20r Subchrons. and comprises the M21n and M20r Sub- tricity (95 ky and 125 ky), while the 4:1 The Windhauseniceras internispinosum chrons (upper Fallauxi to Ponti Standard ratio (4 bundles per superbundles) as low Zone bears only normal polarity that is Zones). Also contains the L. dobeni Sub- frequency eccentricity (410 ky). correlated with the M20n.2n Subchron. zone of the Chitinoidella Zone and the Co- The Arroyo Loncoche section involves 487 Above, the Corongoceras alternans Zone lomisphaera tenuis calcareous dinoflagel- elementary cycles, which are grouped in 98 includes normal, reverse, normal, reverse late Zone. bundles and 24 superbundles (Kietzmann and normal polarities which are interpret- The Windhauseniceras internispinosum et al. 2018). In this section, ammonite data ed to correspond to the upper M20n.2n to Zone has a minimum duration of ~1.21 point to a duration of about 10 myr on the M19n Subchrons. The Substeueroceras myr, and bears only the M20n Subchron, basis of the time scale of Gradstein et al. koeneni Zone comprises normal, reverse, which is consistent with the correlation to (2004, 2012) and Ogg et al. (2016), so that normal, reverse, normal, reverse, normal the Microcanthum Standard Zone (Zeiss the elementary cycle would have a period- and reverse polarities that are correlated and Leanza 2010, Riccardi 2015). Also icity attributable to the precessional cycle with M19n to M16r Subchrons. Further contains the Ch. boneti Subzone of the (~21 ky). Spectral analysis of time series above, the Argentiniceras noduliferum Chitinoidella Zone and the Colomisphaera constructed from thickness of elementary Zone includes a dominant reverse with a tenuis and Colomisphaera fortis calcare- cycles show a peak above the 95% confi- minor opposite polarity, which is correlated ous dinoflagellate Zones, supporting its dence level, and two peaks above the 99% with M16r Subchron. Finally, the Spiticeras early Late Tithonian age. confidence level (Fig. 4). The first one has damesi Zone comprises reverse, normal The Corongoceras alternans Zone has a periodicity of 410 ky, which is consistent and reverse polarities that are interpreted a minimum duration of (~1.21 myr), and with the low-frequency eccentricity cycle. to correspond to M16r to M15r Subchrons. comprises the M20n to M19n2 Subchrons The other two peaks have periodicities of Therefore, deposition of the Vaca Muerta (upper Microcanthum Standard Zone and 118 ky and 91 ky. These periodicities can Formation in the locality of Arroyo Lon- lower part of the “Durangites” Standard be also attributed to the high-frequency coche took place during M22r.2r to M15r Zone). It correlates with the Crassicollaria eccentricity cycle. Using high and low fre- Subchrons. calpionellid Zone and the Colomisphaera quency eccentricity cycles, we built a float- fortis/Stomiosphaerina proxima calcare- ing astronomical scale for the Lower Ti- ous dinoflagellate Zones. thonian-Upper Berriasian of the Neuquén TOWARDS A The Substeueroceras koeneni Zone would Basin, which allowed estimating minimum MULTIDISCIPLINARY have a minimum duration of ~2.43 myr, durations of ammonite zones (Fig. 5). CHRONOSTRATIGRAPHIC comprises the M19n2 to the lowermost CALIBRATION part of M16r Subchrons (upper part of “Du- Magnetostratigraphy rangites” to Occitanica Standard Zones). Virtual Geomagnetic Poles (VGP) were At the base of the Vaca Muerta Forma- This zone contains the Stomiosphaerina calculated from site mean directions, tion, the Virgatosphinctes andesensis proxima calcareous dinoflagellate Zone, yielding 11 reverse and 10 normal polarity Zone shows a minimum duration of 0.81 as well as elements of the Calpionella zones (Fig. 5). One interval at c. 30 m from myr, and comprises the M22r.2r to M22n Zone (Kietzmann 2013 in González To- the base bears no polarity, were a Ceno- Subchrons in the GPTS. The pattern of massini et al. 2015).Taking into account zoic sill was intruded. polarities isolated in this interval rather the two latest proposals of the Jurassic/ Based on the correlation between ammo- correlates to the uppermost Hybonotum Cretaceous boundary, these time-lines nite zones from the Andean and Tethys and lowermost Darwini Standard Zones. at Arroyo Loncoche are placed within the Jurassic-Cretaceous transition in the Neuquén Basin 182

Figure 5. Cyclostratigraphic and magnetostratigraphic scales for the Arroyo Loncoche section (modified from Iglesia Llanos et al. 2017). From left to right are indicated: fa- cies associations (1: distal outer ramp to basin. 2: bioclastic outer ramp. 3: bioclastic middle ramp to proximal outer ramp. 4: Oyster au- toparabiostrome dominated middle ramp), depositional sequences, se- dimentary log and ammonite zones (after Kietzmann et al. 2014), orbi- tal cycles (Kietzmann et al. (2015, 2018) and magnetostratigraphic interpretation (Iglesia Llanos et al. 2017). Grey-shaded bars in deposi- tional sequences are possible stra- tigraphic intervals where there may be condensation and omission of orbital cycles. Red/pink rectangles marks the Cenozoic sill bearing no polarity in the magnetostratigraphic scale Jurassic-Cretaceous transition in the Neuquén Basin 183 lower third of the Substeueroceras koene- tensive discussion about the correlation of of ammonite content, and also widely dis- ni Zone. the Virgatosphinctes andesensiss Zone, cussed in Riccardi (2015). Calpionellid re- Further above, the Argentiniceras nodu- concluding that it correlates most likely ported by Kietzmann (2017) within the A. liferum Zone shows a minimum duration with the Semiforme Zone. However, he proximus, W. internispinosum and C. alter- of ~0.81 myr, and includes a dominant re- does not discard the correlation with the nans fully support their correlation with the verse, which is correlated with M16r Sub- Mazapilites beds of Mexico (Zeiss and Fallauxi to “Durangites” Zones, since the chron (upper Occitanica to lower Boissieri Leanza 2010), a genus that ranges from presence of the Chitinoidella Zone (with Standard Zones). This zone contains the the Hybonotum to the Semiforme Zones. the L. dobeni? and Ch. boneti Subzones) Stomiosphaerina proxima and Stomios- Vennari (2016), on the other hand, pro- was identified for the A. proximus and W. phaera wanneri calcareous dinoflagellate posed to rename the Virgatosphinctes internispinosum Zones, respectively, and Zones being consistent with a Late Berri- andesensis Zone by Virgatosphinctes the Crassicollaria Zone was identified asian age. andesensis Zone, and divided two con- for the C. alternans Zone. Magnetostrati- Finally, the Spiticeras damesi Zone would secutive subzones (Pseudinvoluticeras graphic data indicates that the Jurassic - have a minimum duration of ~1.62 myr primordialis and Indansites malarguensis Cretaceous boundary would be restricted and spans the M16r to M15r Subcrons Subzones), which were partially correlated to the lower part of the S. koeneni Zone (Boissieri Standard Zone), and includes with Darwini and Semiforme Zones. She (M19n.2n Subchron), as proposed by the Stomiosphaera wanneri and lower Co- correlated the P. primordialis Subzone with Leanza (1996). lomisphaera conferta calcareous dinofla- the Darwini Zone, as no typical elements Important nannofossil bioevents were re- gellate Zones, of Late Berriasian age. of the Hybonotum Zone were determined. ported by Vennari et al. (2014) at Las Lo- Nevertheless, she also reported the pres- icas section, including the FOs of N. win- ence of Schaireria neoburgensis a species tereri (M19r Subchron, see Grabowski et DISCUSSION that spans the Hybonotum to Semiforme al. 2017, Wimbledon 2017), and N. kampt- Zones. neri minor and N. steinmannii steinman- The calibration of the Tithonian - Berria- The Pseudolissoceras zitteli Andean nii (M19nSubchron, see Grabowski et al. sian obtained from the combination of dif- Zone is also largely discussed in Riccardi 2017, Wimbledon 2017) in the uppermost ferent disciplines shows good consistency (2015), indicating that although it contains S. koeneni Zone. However, new data from with the ammonite primary scheme pro- ammonites with ranges within the Darwini, Vennari et al. (2017) locate the FOs of N. posed by Riccardi (2015). In this regard, Semiforme and Fallauxi Zones, its most kamptneri minor and N. steinmannii stein- these new data would draw the attention likely equivalence would be the Semiforme mannii at the basal part of the S. koeneni on the fact that there may be small shifts in and lower Fallauxi Zones. New magneto- Zone in Sierra de la Cara Cura section, the correlation of the basal intervals where stratigraphic data from Iglesia Llanos et which are also very consistent with the biostratigraphic data are not conclusive for al. (2017) indicate the upper M22 to lower M19 Chron at the base of the S. koeneni their correlation. M21 Chrons, which are equivalent to the Zone. According to ammonite biostratigraphic upper Darwini to lower Fallauxi Standard According to magnetostratigraphic, cy- proposals, the Virgatosphinctes ande- Zones. Ammonite data do not oppose clostratigraphic and biostratigraphic data sensis Zone is equivalent to the Darwini this chronostratigraphic position. Also, the resulted calibration of ammonite zones and Semiforme Tethyan Zones (Riccardi the presence of the Parastomiosphaera is similar to the biostratigraphic proposal of 2015, Vennari 2016), both of which bear malmica Zone (Ivanova and Kietzmann Leanza (1996) and Riccardi (2015). a single normal polarity (Subchron M22n). 2017), as well as the FO of Polycostella Yet, the polarities pattern isolated in this beckmannii in the middle part of the P. zit- interval rather correlates to the upper- teli Zone (Kietzmann et al. 2011b), is very CONCLUSIONS most Hybonotum and lowermost Darwini consistent with our magnetostratigraphic Zones, which is supported, on the other data. Data provided by magnetostratigraphy al- hand, by the presence of the Carpisto- The following Aulacosphinctes proxi- lowed us to calibrate the Tithonian – Berri- miosphaera tithonica calcareous dinofla- mus, Windhauseniceras internispinosum, asian in the Neuquén Basin with unprece- gellate Zone. The correlation of the lower Corongoceras alternans, Substeueroc- dented precision. This was achieved from Virgatosphinctes andesensis Zone with eras koeneni, Argentiniceras noduliferum, the combination of magnetostratigraphy the Hybonotum Standard Zone was pre- and Spiticeras damesi ammonite Zones with cyclostratigraphy, that where comple- viously proposed by Zeiss and Leanza do correlate very well with the Tethyan mented with calpionellid and calcareous (2010). These authors divided the Virgato- Zones in Riccardi (2015), as well as the dinocyst biostratigraphy. The latter convey sphinctes andesensis Zone into a lower new cyclostratigraphic (Kietzmann et al. similar distributions than those proposed in “Lithacoceras” malarguense Subzone and 2015), magneostratigraphic (Iglesia Lla- Leanza (1996), Zeiss and Leanza (2010), an upper Choicensisphinctes choicensis nos et al. 2017) and biostratigraphic data and Riccardi (2015). Subzone, which were referred respective- (Kietzmann 2017, Ivanova and Kietzmann The resultant cyclo and magnetostrati- ly to the Hybonotum and Darwini Zones 2017) (Fig. 6). This correlation was earlier graphic scales suggest that the deposition (Fig. 6). Riccardi (2015) provides an ex- proposed by Leanza (1996) on the basis of the Vaca Muerta Formation in the local- Jurassic-Cretaceous transition in the Neuquén Basin 184 - et al. (2017). (2014)/Vennari (2016) and (2014)/Vennari al. et ammonite zones. Correlations Leanza (1980, 1996), Zeiss and (2010), Vennari from Tethyan Andean and correlation proposals between Comparisiondifferent 6. of Figure Riccardi (2015) are based on ammonite and nannofossil biostratigraphic information.Correlation al. (2017)/this work is based on magnetostratigraphic from Iglesia Llanos et and calcareous microfossils biostratigra phy. Note the high similarities between correlations obtained independently by Leanza (1996), Riccardi (2015) and Iglesia Llanos phy. Jurassic-Cretaceous transition in the Neuquén Basin 185

ity of Arroyo Loncoche took place during y Recursos Naturales de la Provincia del ción Vaca Muerta (Tithoniano superior), alta Chrons M22 to M16 in a minimum time of Neuquén. Asociación Geológica Argentina: cordillera mendocina, Argentina. 13º Con- 10.13 myr (4.86 for the Tithonian and 5.27 489-528, Buenos Aires. greso Geológico Argentino y 3º Congreso de for the Berriasian). Bown, P. and Ellison, C. 1995. Jurassic-Early Exploración de Hidrocarburos, Actas 5: 225, The proposed stratigraphic calibration of Cretaceous nannofossils from the Neuquén Mendoza. the Tithonian-Berriasian Andean succes- Basin, Argentina. Journal of Nannoplankton Giambiagi, L., Bechis, F., Lanés, S., Tunik, M., sion brings foward two key points: 1) The Research 17: 48. García, V., Suriano, J. and Mescua, J. 2008. base of the Vaca Muerta Formation (V. Bown, P. and Concheyro, A. 2004. Lower Cre- Formación y evolución triásico-jurásica del andesensis Zone) shows a polarities pat- taceous calcareous nannoplankton from the Depocentro Atuel, Cuenca Neuquina, pro- tern which would only be compatible to the Neuquén Basin, Argentina. Marine Micropa- vincia de Mendoza. Revista de la Asociación uppermost part of Hybonotum Zone. This leontology 52: 51-84. Geológica Argentina 63: 520-533. correlation is consistent with the C. tithon- Carozzi, A.V., Bercowski, F., Rodriguez, M., Goldhammer, R.K., Dunn, P.A. and Hardie, ica calcareous dinocysts Zone. 2) The po- Sanchez, M. and Vonesch, T. 1981. Estudio L.A. 1990. Depositional cycles, composite sition of the Jurassic - Cretaceous bound- de microfacies de la Formación Chachao sea-level changes, cycle stacking patterns, ary within the lower third of the S. koeneni (Valanginiano), Provincia de Mendoza. 8º and the hierarchy of stratigraphic forcing. Zone is in very good agreement with the Congreso Geológico Argentino, Actas 2: Geological Society of America Bulletin 102: biostratigraphic proposal of Leanza (1996) 545-565, San Luis. 535-562. and Riccardi (2015). Casellato, C.E. 2010. Calcareous nannofossil González Tomassini, F., Kietzmann, D.A., Fan- biostratigraphy of Upper Callovian – Lower tín, M.A, Crousse, L.C. and Reinjenstein, Berriasian successions from the Southern H.M. 2015. Estratigrafía y análisis de facies ACKNOWLEDGMENTS Alps, North Italy. Rivista Italiana di Paleonto- de la Formación Vaca Muerta en el área de logia e Stratigrafia 116: 357-404. El Trapial, Cuenca Neuquina, Argentina. Pe- This research has been done under the Desjardins, P., Fantín, M.A., González Tomas- trotecnia 2015: 78-89. framework of the PICT-2015-0206 and sini, F., Reijenstein, H.M., Sattler, F., Domin- Grabowski, J. 2011. Magnetostratigraphy of the PICT-2016-3762 projects supported by guez, F., Kietzmann, D.A., Leanza, H.A., Jurassic/Cretaceous boundary interval in the Agencia Nacional de Promoción Bande, A., Beinot, S., Borgnia, M., Vittore, the Western Tethys and its correlations with Científica y Tecnológica, and UBACyT F., Simo, T. and Minisini, D. 2016. Estrati- other regions: a review. Volumina Jurassica 20020150200218BA project supported grafía sísmica regional. In: González, G., 9: 105-128. by the University of Buenos Aires. We Vallejo, D., Kietzmann, D.A., Marchal, D., Grabowski, J., Lakova, I., Petrova, S., Stoykova, are especially grateful to Dr. Alberto Ric- Desjardins, P., González Tomassini, F., Gó- K., Dimitrov, S., Ivanova, D.K., Wojcik-Tabol, cardi (Universidad Nacional de La Plata mez Rivarola, L. and Domínguez, F. (eds.), P., Sobień, K., Schnabl, P. 2016. The Czech y Museo, Argentina) for ammonites and Transecta regional de la Formación Vaca Academy of Sciences 2016. Paleomagne- ammonite zones identification, as well as Muerta. Integración y correlación de sísmi- tism and integrated stratigraphy of the Upper the discussion of Tithonian–Valanginian ca, perfilaje de pozos, coronas y afloramien- Berriasian hemipelagic succession in the biostratigraphy. We especially appreciate to. IAPG-AGA: 5-22, Buenos Aires. Barlya section Western Balkan, Bulgaria: the review and editorial work of Héctor Enay, R. and Geyssant, J.R. 1975. Faunes ti- Implications for lithogenic input and paleore- Leanza. thoniques des chaînes betiques (Espagne dox variations. Palaeogeography Palaeocli- méridionale). Colloque sur la limite juras- matology Palaeoecology 461: 156-177. REFERENCES sique-cretace. Memoir BRGM 86: 39-55, Grabowski, J., Haas, J., Stoykova, K., Wierz- Lyon. bowski, H., and Brański, P. 2017. Envi- Alleman, F., Catalano, R., Fares, F., and Rema- Fernández-Carmona, J. and Riccardi, A.C. ronmental changes around the Jurassic/ ne, J. 1971. Standard calpionellid zonation 1998. First record of Chitinoidella Doben in Cretaceous transition: New nannofossil, (Upper TithonianeValanginian) of the Wes- the Tithonian of Argentina. 10º Congreso chemostratigraphic and stable isotope data tern Mediterranean province. In: Farinacci, Latinoamericano de Geología y 6º Congreso from the Lókút section (Transdanubian Ran- A. (ed.), Proceedings of the II Planktonic Nacional de Geología Económica, Actas 1: ge, Hungary). Sedimentary Geology 360: Conference: 1337-1340, Roma. 292, Buenos Aires. 54-72. Anderson, E.J. 2004. The cyclic hierarchy of the Fernandez Carmona, J. and Riccardi, A.C. Gradstein, F.M., Ogg, J.G., Schmith, A.G. 2004. “Purbeckian” Sierra del Pozo Section, Lower 1999. Primer reporte de calpionélidos cal- A Geologic Time Scale. Cambridge Universi- Cretaceous (Berriasian), southern Spain. cáreos del Cretácico inferior -Berriasiano ty Press, 401 p., Cambridge. Sedimentology 51: 455-477. de la Provincia del Tethys en la República Gradstein, F.M., Ogg, J.G., Schmitz, M.D. and Ballent, S., Concheyro, A., Náñez, C., Pujana, Argentina: Conexión Tethys-Pacífico. Bole- Ogg, G.M. 2012. The Geologic Time Scale, I., Lescano, M., Carignano, A.P., Caramés, tim do Simposio sobre o Cretáceo do Brasil: Elsevier, 1144, Oxford. A., Angelozzi, G., and Ronchi, D. 2011. 465-466. Hoedemaeker, P.J. 1990. The Neocomian Microfósiles mesozoicos y cenozoicos. In: Fernández-Carmona, J., Álvarez, P.P. and Agui- boundaries of the Tethyan Realm based on Leanza, H.A., Arregui, C., Carbone, O., Da- rre-Urreta, M.B. 1996. Calpionélidos calcá- the distribution of ammonites. Cretaceous nieli, J.C. and Vallés, J.M. (eds.), Geología reos y grupos incertae sedis en la Forma- Research 11: 331-342. Jurassic-Cretaceous transition in the Neuquén Basin 186

Iglesia Llanos, M.P., Kietzmann, D.A., Kohan gentina: Implications for the Jurassic-Creta- metry of Back Arc Basin, Central Argentina Martinez, M. and Palma, R.M. 2017. Magne- ceous boundary in the Neuquén Basin. Sedi- Andes. In McDonald, D.I.M. (ed.), Sea level tostratigraphy of the Upper Jurassic-Lower mentary Geology 315: 29-46. changes at active plate margins: Process Cretaceous of Argentina: Implications for the Kietzmann, D.A., Iglesia-Llanos, M.P., and Ko- and product. International Association of Se- Jurassic-Cretaceous boundary in the Neu- han Martínez, M. 2018. Astronomical cali- dimentologists, Special Publication 12: 429- quén Basin. Cretaceous Research 70:189- bration of the Upper Jurassic-Lower Creta- 450, Oxford. 208. ceous in the Neuquén Basin, Argentina: a Legarreta, L. and Uliana, M.A. 1996. The Ju- Ivanova, D.K. and Kietzmann, D.A. 2017. Cal- contribution from the Southern Hemisphere rassic succession in west central Argentina: careous dinoflagellate cysts from the Titho- to the Geologic Time Scale. In: Montenari, M. stratal patterns, sequences, and paleogeo- nian - Valanginian Vaca Muerta Formation in (ed.), Stratigraphy & Timescales 3. Elsevier, graphic evolution. Palaeogeography, Pa- the southern Mendoza area of the Neuquén in press. laeoclimatology, Palaeoecology 120: 303- Basin, Argentina. Journal of South American Lakova, I., Stoykova, K. and Ivanova, D. 1999. 330. Earth Sciences 77: 150-169. Calpionellid, nannofossil and calcareous Lescano, M.A. and Concheyro, A. 2009. Na- Kietzmann, D.A. 2017. Chitinoidellids from the dinocyst bioevents and integrated biochro- nofósiles calcáreos de la Formación Agrio Tithonian-Valanginian Vaca Muerta Forma- nology of the Tithonian to Valanginian in the (Cretácico Inferior) en el sector sudocciden- tion, Neuquén Basin, Argentina. Journal of Western Balkanides, Bulgaria. Geologica tal de la Cuenca Neuquina, Argentina. Ame- South American Earth Sciences 76: 152- Carpathica 50: 151-158. ghiniana 46: 73-94. 164. Leanza, A.F. 1945. Amonites del Jurásico su- Lescano, M.A. and Concheyro, A. 2014. Nano- Kietzmann, D.A. and Palma, R.M. 2009. Micro- perior y del Cretacico inferior de la Sierra cónidos del Grupo Mendoza (Cretácico Infe- crinoideos saccocómidos en el Tithoniano Azul, en la parte meridional de la provincia rior) en la Provincia del Neuquén, República de la Cuenca Neuquina. ¿Una presencia de Mendoza. Anales Museo La Plata: 1-99. Argentina: Taxonomía, Cronoestratigrafía e inesperada fuera de la región del Tethys? Leanza, H.A. 1980. The Lower and Middle Ti- Implicancias Paleogeográficas. Ameghinia- Ameghiniana 46: 695-700. thonian Ammonite Fauna from Cerro Lotena, na 51: 466-499. Kietzmann, D.A., Palma, R.M. and Bressan, Province of Neuquén, Argentina. Zitteliana 5: Manceda, R. and Figueroa, D., 1993. La inver- G.S. 2008. Facies y microfacies de la rampa 3-49. sión del rift mesozoico de la faja fallada y tithoniana-berriasiana de la Cuenca Neuqui- Leanza, H.A. 1996. Advances in the ammonite plegada de Malargüe. Provincia de Mendo- na (Formación Vaca Muerta) en la sección zonation around the Jurassic/Cretaceous za. 12º Congreso Geológico Argentino y 2º del arroyo Loncoche – Malargüe, provincia boundary in the Andean Realm and corre- Congreso de Exploración de Hidrocarburos, de Mendoza. Revista Asociación Geológica lation with Tethys. Jost Wiedmann Sympo- Actas 3: 219-232, Mendoza. Argentina 63: 696-713. sium, Abstracts: 215-219, Tübingen. Mitchum, R.M. and Uliana, M. 1985. Seismic Kietzmann, D.A., Blau, J., Riccardi, A.C. and Leanza, H.A. 2009. Las principales discordan- stratigraphy of carbonate depositional se- Palma, R.M. 2011a. An interesting finding of cias del Mesozoico de la Cuenca Neuquina quences, Upper Jurassic-Lower Cretaceous, chitinoidellids (Calpionellidea Bonet) in the según observaciones de superficie. Revista Neuquén Basin, Argentina. In Berg, B.R. and Jurassic-Cretaceous boundary of the Neu- del Museo Argentino de Ciencias Naturales Woolverton, D.G. (eds.), Seismic Stratigra- quén Basin. 18º Congreso Geológico Argen- 11: 145-184. phy 2. An integrated approach to hydrocar- tino, Actas CD: 1480-1481, Neuquén. Leanza, H.A. and Hugo, C.A. 1977. Sucesión bon analysis. AAPG Memoir 39: 255-283, Kietzmann, D.A., Martín-Chivelet, J., Palma, de ammonites y edad de la Formación Vaca Tulsa. R.M., López-Gómez, J., Lescano, M. and Muerta y sincrónicas entre los paralelos 35 y Musacchio, E.A. 1978. Microfauna del Jurásico Concheyro, A. 2011b. Evidence of preces- 40 l.s. Cuenca Neuquina-Mendocina. Revis- y Cretácico Inferior. Geología y Recursos sional and eccentricity orbital cycles in a ta de la Asociación Geológica Argentina 32: Naturales del Neuquén. Relatorio VII Con- Tithonian source rock: the mid-outer carbo- 248-264. greso Geológico Argentino: 147-163, Bue- nate ramp of the Vaca Muerta Formation, Leanza, H.A., Marchese, H.G. and Riggi, J.C. nos Aires. Northern Neuquén Basin, Argentina. AAPG 1977. Estratigrafía del Grupo Mendoza con Nowak,W. 1968. Stomiosferidy warstw cieszy- Bulletin 95: 1459-1474. especial referencia a la Formación Vaca nskich (kimeryd - hoteryw) polskiego Slaska Kietzmann, D.A., Palma, R.M., Riccardi, A.C., Muerta entre los Paralelos 35º y 40º l.s. cieszynskiego i ich znaczenie stratygraficz- Martín-Chivelet, J. and López-Gómez, J. Cuenca Neuquina-Mendocina. Revista de ne. Rocznik Polskiego Towarzystwa Geolo- 2014. Sedimentology and sequence strati- la Asociación Geológica Argentina 32: 190- gicznego 38: 275-327. graphy of a Tithonian - Valanginian carbonate 208. Ogg, J.G. and Hinnov, L.A. 2012. The Jurassic ramp (Vaca Muerta Formation): A misunders- Legarreta, L. and Gulisano, C.A. 1989. Análisis Period. In Gradstein, F.M., Ogg, J.G., Sch- tood exceptional source rock in the Southern estratigráfico de la Cuenca Neuquina (Triási- mitz, M.D. and Ogg, G.M. (eds.), The Geo- Mendoza area of the Neuquén Basin, Argen- co Superior-Terciario Inferior). In Chebli, G.A. logic Time Scale 2012. Elsevier: 731-792, tina. Sedimentary Geology 302: 64-86. and Spalletti, L.A. (eds.), Cuencas Sedimen- Oxford. Kietzmann, D.A., Palma, R.M. and Iglesia Lla- tarias Argentinas. Serie Correlación Geológi- Ogg, J.G., Ogg, G.M. and Gradstein, F.M. 2016. nos, M.P. 2015. Cyclostratigraphy of an orbi- ca 6: 221-243 p., San Miguel de Tucumán. A Concise Geologic Time Scale. Elsevier, tally-driven Tithonian-Valanginian carbonate Legarreta, L. and Uliana, M.A. 1991. Jurassic– 243 p., Amsterdam. ramp succession, Southern Mendoza, Ar- Cretaceous Marine Oscillations and Geo- Pardo-Igúzquiza, E. and Rodríguez-Tovar, F., Jurassic-Cretaceous transition in the Neuquén Basin 187

2004. POWGRAF 2: a program for graphical siles calcáreos, duración y origen de ciclos V.A. 2014. New constraints on the Juras- spectral analysis in cyclostratigraphy. Com- caliza-marga (Jurásico tardío de la Cuenca sic-Cretaceous boundary in the High Andes puters and Geosciences 30: 533-542. Neuquina). Revista de la Asociación Geoló- using high-precision U-Pb data. Gondwana Ramos, V.A. 2010. The tectonic regime along gica Argentina 54: 290-297. Research 26: 374-385. the Andes: Present-day and Mesozoic regi- Scasso, R.A, Alonso, S.M., Lanés, S., Villar, Vennari, V.V., Lescano, M., Aguirre-Urreta, B., mes. Geological Journal 45: 2-25. H.J., and Lippai, H. 2005. Geochemistry Concheyro, A., Fantín, M., Vallejos, M.D., Ramos, V.A. and Folguera, A. 2005. Tectonic and petrology of a Middle Tithonian limes- Depine, G., Sagasti, G. and Ambrosio, A., evolution of the Andes of Neuquén: constra- tone-marl rhythmite in the Neuquén Basin, 2017. Avances en la Bioestratigrafía de alta ints derived from the magmatic arc and Fo- Argentina: depositional and burial history. resolución de la Formación Vaca Muerta: reland deformation. In Veiga, G.D., Spalletti, In: Veiga, G.D., Spalletti, L.A., Howell, J.A. amonites y nanofósiles calcáreos integrando L.A., Howell, J.A. and Schwarz, E. (eds.), and Schwarz, E. (eds.), The Neuquén Basin, datos de subsuelo y afloramientos. XX Con- The Neuquén Basin, Argentina: a Case Argentina: A Case Study in Sequence Stra- greso Geológico Argentino, Actas Simposio Study in Sequence Stratigraphy and Basin tigraphy and Basin Dynamics. Geological Geología de Vaca Muerta: 168-172, San Mi- Dynamics. Geological Society of London, Society of London, Special Publication 252: guel de Tucumán. Special Publications 252: 15-35, London. 207-229, London. Vergani, G.D., Tankard, A.J., Belotti, H.J. and Reháková, D. 2000a. Calcareous dinoflagellate Schwarzacher, W. 1993.Cyclostratigraphy and Welkink, H.J. 1995. Tectonic evolution and and calpionellid bioevents versus sea-level the Milankovitch theory. Developments in paleogeography of the Neuquén Basin, Ar- fluctuations recorded in the West-Carpa- sedimentology 52, 224 p., Amsterdam. gentina. In: Tankard, A.J., Suarez Soruco, R. thian (/) pela- Strasser, A., Hillgärtner, H. and Pasquier, J.B. and Welsink, H.J. (eds.), Petroleum Basins gic environments. Geologica Carpathica 51: 2004.Cyclostratigraphic timing of sedi- of South America. AAPG Memoir 62: 383- 229-243. mentary processes: An example from the 402, Tulsa. Reháková, D. 2000b. Evolution and distribution Berriasian of the Swiss and French Jura Wimbledon, W.A.P. 2008. The Jurassic-Cre- of the Late Jurassic and early Cretaceous Mountains. In: D’Argenio, B., Fischer, A.G., taceous boundary: An age-old correlative calcareous dinoflagellates recorded in the Premoli Silva, I., Weissert, H. and Ferreri, enigma. Episodes 31: 423-428. Western Carpathians pelagic carbonate fa- V. (eds.), Cyclostratigraphy: Approaches Wimbledon, W.A.P. 2017. Developments with cies. Mineralia Slovaca 32: 79-88. and Case Histories. Society of Economic fixing a Tithonian/Berriasian (J/K) boundary. Řehánek, J. 1992. Valuable species of cadosi- Paleontologists and Mineralogists, Special Volumina Jurassica XV: 181-186. nids and stomiosphaerids for determination Publication 81: 135-151. Zeiss, A. and Leanza, H.A. 2010. Upper Juras- of the Jurassic-Cretaceous boundary (ver- Uliana, M.A., and Legarreta, L. 1993. Hydro- sic (Tithonian) ammonites from the lithogra- tical distribution, biozonation). Scripta 22: carbons habitat in a Triassic-to-Cretaceous phic limestones of the Zapala region, Neu- 117-122. Sub-Andean setting: Neuquén Basin, Ar- quén Basin, Argentina. Beringeria 41: 23-74. Remane, J. 1991. The Jurassic-Cretaceous gentina. Journal of Petroleum Geology 16: boundary: problems of definition and proce- 397-420. dure. Cretaceous Research 12: 447-453. Vennari, V.V. 2016. Tithonian ammonoids Riccardi, A.C. 2008. The marine Jurassic of Ar- (Cephalopoda, ) from the gentina: a biostratigraphic framework. Epi- Vaca Muerta Formation, Neuquén Basin, sodes 31: 326-335. West-Central Argentina. Palaeontographica, Riccardi A. 2015. Remarks on the Tithonian– Abt. A: Palaeozoology – Stratigraphy 306: Berriasian ammonite biostratigraphy of west 85-165. central Argentina. Volumina Jurassica 13: Vennari, V.V., Lescano, M., Naipauer, M., Agui- 23-52. rre-Urreta, B., Concheyro, A., Schaltegger, Recibido: 15 de diciembre, 2017 Scasso, R.A. and Concheyro, A. 1999. Nanofó- U., Armstrong, R., Pimentel, M. and Ramos, Aceptado: 7 de mayo, 2018