Upper Jurassic

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Upper Jurassic ammonites and bivalves from the Cucurpe Formation, Sonora (Mexico)

Upper Jurassic ammonites and bivalves from the Cucurpe Formation, Sonora (Mexico)

Four new molluscan assemblages from north-central Sonora indicate that the Cucurpe Formation ranges in age from late Oxfordian to early Tithonian. These assemblages extend the known paleogeographic range of Late Jurassic Tethyan fossil groups several hundred km to the northwest and improve correlation of Upper Jurassic strata in northern Mexico. At Rancho La Colgada, near the town of Tuape, the upper part of the Cucurpe Formation consists of 515 m of shale, siltstone, basaltic flows and minor sandstone. The oldest fossil assemblage is assigned to the Bifurcatus Zone of the lower upper Oxfordian and contains the ammonites Perisphinctes (Dichotomoceras?) sp., Sequeirosia? sp., and the bivalves Grammatodon (Grammatodon) hersilius (d´Orbigny), Parainoceramus sp., “Lucina” potosina Aguilera, “Lucina” sp., and Isocyprina? sp. The second assemblage is assigned to the lower Tithonian (lower part of the Albertinum/Darwini Zone) and consists of the ammonites Mazapilites mexicanus (Aguilera), Schaireria neoburgensis (Oppel), Subplanitoides sp., and Glochiceras (Lingulaticeras?) sp. The third fossil assemblage from the uppermost part of the section includes the ammonites Sublithacoceras cf. sphinctum (Schneid), Sublithacoceras sp., and Pachysphinctes sp., and the bivalves “Lucina” potosina Aguilera and Integricardium (Integricardium) sp. This assemblage belongs to the Semiforme-Verruciferum Zone to Richteri Zone of the middle lower Tithonian. A fourth assemblage is assigned to the lower Tithonian, representing the middle to upper part of the Albertinum-Darwini or the lowermost part of the Semiforme- Verruciferum Zone. This assemblage was collected from the upper part of the Cucurpe Formation at a nearby locality and contains the ammonites Torquatisphinctes subbleicheri (Burckhardt), T. cf. lauri (Aguilera) and Torquatisphinctes sp. cf. T. diversecostatus (Burckhardt). The absence of Kimmeridgian fossils in the measured section at Rancho La Colgada and a conglomerate between the Oxfordian and Tithonian assemblages combine to indicate an unconformity in the Upper Jurassic interval that omits the Kimmeridgian. A single Kimmeridgian ammonite was recently collected in the Cucurpe Formation about 40 km northwest of the study area.

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Grazing activity as taphonomic record of necrobiotic interaction: A case study of a sea turtle carapace from the Upper Jurassic of the Prebetic (south Spain)

Grazing activity as taphonomic record of necrobiotic interaction: A case study of a sea turtle carapace from the Upper Jurassic of the Prebetic (south Spain)

Bioerosion trace fossils can shed light on the ecological interactions between species. Here we describe an unusual case of bioerosion on a turtle carapace of Hispaniachelys prebetica from the Oxfordian (around 155 Ma, Upper Jurassic) of the Prebetic (Betic Cordillera, South Spain). The specimen was found in a limestone bed of a marl-limestone rhythmite. Morphological analysis of the bioerosive structures reveals the dominance of epigenic traces produced by the grazing activity of regular sea urchins (ichnospecies Gnathichnus pentax). No other bioerosion structures are present. From an ethologic point of view only epigenic traces (pascichnia) are present. Gnathichnus pentax records short-term bioerosion produced exclusively on the carapace before its burial. The ichnological assemblage recorded herein typifies the Gnathichnus Ichnofacies. The carapace was the most favourable hard substrate for grazers in comparison to the surrounding muddy soft bottom. The carapace was oriented convex-down when found in the rock. Therefore, pascichnial activity probably occurred early after the death and accumulation on the sea floor of the turtle remains, but before the carapace was overturned by large scavengers. The low degree of fragmentation and the low dispersion of skeletal components indicate a low-energy environment and early burial in the sea bottom. Key words: Turtle carapace; bioerosion; Gnathichnus; gnawing organisms; regular echinoids; Upper Jurassic.

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The Tithonian (Upper Jurassic) ammonite succession at Portada Covunco, Neuquén Mendoza Basin, Argentina

The Tithonian (Upper Jurassic) ammonite succession at Portada Covunco, Neuquén Mendoza Basin, Argentina

Portada Covunco is a locality of the southern part of the Neuquén-Mendoza Basin in which the upper Jurassic is well exposed. This locality belongs to the Geological Sheet 35b – Zapala, which was described in detail by Lambert (1956). There are no published reports of the local section measured in detail with ammonites collected bed- by-bed, probably due to the scarce ammonite fauna. It is interesting to note that all the Upper Jurassic of the studied locality has yielded very scarce and poorly preserved ammonites, the exception being the lower Tithonian in which the fossils are also poorly preserved but somewhat more abundant.

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First record of the genus Trichites (Mollusca, Bivalvia) from the Upper Jurassic (Kimmeridgian) of Santiago Coatepec, Puebla, Mexico

First record of the genus Trichites (Mollusca, Bivalvia) from the Upper Jurassic (Kimmeridgian) of Santiago Coatepec, Puebla, Mexico

This article proves the presence of the bivalve of the genus Trichites in the Upper Jurassic of Santiago Coatepec, a small area located at the southeast of the state of Puebla, Mexico, and describes a new species, Trichites pueblaensis. This is also the first Upper Jurassic record of the genus for the American continent. The associated larger foraminifera indicate a Kimmeridgian age for this sedimentary sequence. Other important aspect is that during about two centuries it was supposed that the genus Trichites did not exist in the American continent. However, in this article is shown that this assumption was wrong, because the genus has been reported from some places of the western hemisphere. Key words: Trichites, bivalve, larger foraminifers, Upper Jurassic, Mexico.

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The Upper Jurassic volcanism of the Río Damas Tordillo Formation (33°  35 5°S): Insights on petrogenesis, chronology, provenance and tectonic implications

The Upper Jurassic volcanism of the Río Damas Tordillo Formation (33° 35 5°S): Insights on petrogenesis, chronology, provenance and tectonic implications

ABSTRACT. The uppermost Jurassic continental and volcanic deposits of the Río Damas-Tordillo Formation represent an interval of intense continental deposition within the Jurassic to Early Cretaceous dominantly marine environment of the Mendoza-Neuquén back-arc basin. Stratigraphic and geochronological data indicate that progressive emersion of the arc and forearc domain, disconnecting the back-arc region from the Pacific Ocean, occurred during occurred during the Late Jurassic and probably the Early Cretaceous (~160-140 Ma). This change in the margin configuration induced a marine regression and the subsequent deposition of continental material in the back-arc basin. The most likely source of the sediments would have been the Jurassic arc, located west of the back-arc basin. The maximum depositional age of 146.4±4.4 Ma obtained from a red sandstone immediately below volcanic rocks confirms recent Tithonian maximum depositional ages assigned to the Río Damas-Tordillo Formation, and suggests that the volcanic rocks, overlain by marine fossiliferous Tithoninan-Hauterivian sequences, should have erupted within a short time span during the Late Jurassic. Volcanism was probably facilitated by the presence of extensional structures related to the formation of the back-arc basin. Elemental and isotopic data, along with forward AFC models, suggest a depleted sub-arc asthenospheric mantle source for the volcanic rocks and the fractionation of olivine and plagioclase, along with small volumes of lower crust assimilation, as the main processes involved in the magmatic evolution. It is not possible to establish a different source and petrogenetic conditions for the Río Damas-Tordillo Formation and the magmatism in the arc domain located further west, at the present-day Coastal Cordillera.

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The Middle Tithonian (Upper Jurassic) Ammonoid fauna of Cañadón de los Alazanes, southern Neuquén Mendoza Basin, Argentina

The Middle Tithonian (Upper Jurassic) Ammonoid fauna of Cañadón de los Alazanes, southern Neuquén Mendoza Basin, Argentina

were seen in the field. The Middle Tithonian strata (Zitteli, During petroleum prospection in Neuquén Province, a new Proximus and Internispinosum Biozones) span about 35 m section of the Andean Tithonian was recently exposed in in the Vaca Muerta Fm. They consist of black shales with Cañadón de Los Alazanes (Fig. 1), near Manzano limestone concretions at the base, and limestone and Escondido at the southern tip of Cordón Curymil, Sierra mudstone banks upwards in the section. The lithologic and Vaca Muerta (Hoja Geológica 35b Zapala, Lambert 1956). ammonite successions of Cañadón de los Alazanes (Fig. 2) In a recent field work Middle and Upper Tithonian and are the same as at Mallín Quemado and Mallín de los typically Perigondwanic ammonites were collected in that Caballos (cf. Leanza 1973, Leanza 1975, Leanza and Hugo section. Tithonian ammonites from this locality were never 1977), but it is a half of the thickness, decreasing from described, only some indirect references may be found in Mallín de Los Caballos, surely in relation with the Lambert (1956). Although the material is scarce its proximity to the shelf edge at Cañadón de los Alazanes. At des cri pti on is use ful bot h pal eon tol ogi cal ly and the top, the Picún Leufú Fm. consisting of yellow massive biostratigraphically on the basis of the precise sampling of limestones overlies the black shales and marls of the upper the succession and the occurrence of some taxa which need part of the Vaca Muerta Fm. (see Lambert 1956: fig. 4, revision or are poorly known. Leanza 1973, Leanza and Zeiss 1990, 1992) from which The associated gastropod fauna from beds CA02- were collected Berriasian ammonites near Los Catutos 04 (Fig. 2) is described by Gründel and Parent (2001). (between Zapala and Portada Covunco). These yellow The aim of this paper is to describe the new section limestones must correpond to the distal lens of the Picún and its ammonite fauna and to discuss the biostratigraphical Leufú Fm. described by Leanza (1973).

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Calpionellid biostratigraphy, U-Pb geochronology
				and microfacies of the Upper Jurassic-Lower Cretaceous Pimienta
				Formation (Tamazunchale, San Luis Potosí, central-eastern Mexico)

Calpionellid biostratigraphy, U-Pb geochronology and microfacies of the Upper Jurassic-Lower Cretaceous Pimienta Formation (Tamazunchale, San Luis Potosí, central-eastern Mexico)

Detailed sampling of a stratigraphic section corresponding to the La Pimienta Formation in the state of San Luis Potosí allows the determination of the upper Tithonian Crassicollaria Zone (Remanei, Brevis and Colomi Subzones). The presence of Praetintinnop- sella andrusovi Borza and chitinoidellids in the Crassicollaria Zone, was interpreted as the result of sedimentary reworking as due to fact that these taxa have not been reported in such a high stratigraphic position. Nonetheless additional work is needed in order to establish a clear relationship. The U-Pb date for a bentonite bed that underlies rocks of the Elliptica Subzone is 139.1 ± 2.6 Ma (late Berriasian-early Valanginian). These new data suggest a different age range for the Elliptica Subzone in Mexico as compared with coeval sections in the Mediterranean Tethys.

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Protolith age of the Altar and Carnero complexes and latest Cretaceous–Miocene deformation in the Caborca–Altar region of northwestern Sonora, Mexico

Protolith age of the Altar and Carnero complexes and latest Cretaceous–Miocene deformation in the Caborca–Altar region of northwestern Sonora, Mexico

In contrast to the broad consensus regarding Laramide and younger history, the protolith age of El Batamote belt has long been a matter of debate. Jacques-Ayala et al. (1990, 2009), García y Barragán et al. (1998) and Jacques-Ayala (1999, 2000) concluded that a significant fraction of the protolith was Upper Cretaceous; i.e. younger than the Bisbee Group and either correlative with or younger than El Chanate Group. In their view, the Upper Cretaceous component of the protolith represents, at least in part, a synorogenic succession deposited in front of, and eventually overridden by, a Laramide thrust complex. The proposed thrust faults, however, have not been definitively identified; they may be buried beneath younger deposits and/or have been excised by middle Cenozoic extensional faults. Alternatively, Nourse (1995; 2001) and Anderson and Nourse (2005) considered that the protolith of El Batamote belt was entirely Upper Jurassic to Lower Cretaceous and correlative with the Glance Conglomerate, the lowest formation of the Bisbee Group. Nourse (1995; 2001) and Anderson and Nourse (2005) further argued that the elongate geometry of El Batamote belt was inherited from deposition in a narrow transtensional (pull-apart) basin adjacent to the inferred Late Jurassic Mojave-Sonora megashear. As such, their proposed Late Jurassic–Early Cretaceous protolith age for the complex represents a primary line of evidence for the megashear in the Caborca–Altar area.

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Variability and symmetry of a Jurassic nocturnal predatory cockroach (Blattida: Raphidiomimidae)

Variability and symmetry of a Jurassic nocturnal predatory cockroach (Blattida: Raphidiomimidae)

Carnivorous cockroaches, as one of most aberrant insects, were recognized based on the few complete individuals originating from the Upper Jurassic sediments of Karatau in Kazakhstan (Vishniakova, 1973). Cosmopolitan Jurassic-Cretaceous representatives of the genus Liadoblattina Handlirsch, 1906 were also categorized within this family and these insects appeared as to be common during the whole Jurassic (Vršanský and Ansorge, 2007; Liang et al., 2009) except at the locality of Mintaja in Australia (Martin, 2010), where they were apparently absent or extremely rare. The single published Cretaceous record from Myanmar (Grimaldi and Ross, 2004) is obscure (Vršanský, 2009).

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Facies analysis and depositional environments of the Upper Cretaceous Sadr unit in the Nakhlak area, Central Iran

Facies analysis and depositional environments of the Upper Cretaceous Sadr unit in the Nakhlak area, Central Iran

The Upper Cenomanian to Campanian rocks (Sadr unit) crop out across a large area of Nakhlak and reach a thickness of 258 m in the studied section (Figure. 1). This section is situated south of Nakhlak village (coordinates: N 33˚32’09”; E 53˚50’33”) and consists of conglomerates, sandy limestones, calcareous sandstones, sandy dolostones, sandy-argillaceous limestones, sandy dolomitic limestones, and reefal limestones that have been subdivided into ten sub- units on the basis of their facies characteristics and described (Figure 2; Vaziri et al., 2005). The rich foraminiferal assem- blage from different sub-units of the studied section indicates a Late Cenomanian to Campanian age (Khosrow-Tehrani, 1977; Vaziri et al., 2005). Biostratigraphic studies of the Upper Cretaceous rocks of the Nakhlak (Khosrow-Tehrani 1977; Vaziri et al., 2005), Choopanan and Hafttoman areas (Khosrow-Tehrani, 1977), as well as of the Kerman area of east-central Iran (Faryabi, 2003) point to a hiatus during Turonian-Coniacian time.

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Mundo jurásico y mundo de la vida : la constitución de los animales prehistóricosJurassic world and life world : the constitution of prehistoric animals

Mundo jurásico y mundo de la vida : la constitución de los animales prehistóricosJurassic world and life world : the constitution of prehistoric animals

Esto es precisamente lo que sucede con las ciencias que estudian a los fósiles. Los modelos que establece la paleontología para comprender al dinosaurio se transfieren a la experiencia no-científica de modo que la re-perspectivan, es decir, modifican su manera de darse originaria mediante correcciones, ampliaciones y una determinación más próxima (Näherbestimmung) de sus sentidos noemáticos. Y esta modificación acontece en las dos maneras de la presentificación compleja a través de imágenes y signos lingüísticos. Las primeras pueden ser imágenes fijas, como las láminas en los libros escolares, o imágenes en movimiento, como en los videos educativos, pero también reconstrucciones tridimensionales, que van desde los muñecos para niños hasta los gigantes mecánicos de los parques temáticos construidos a partir de Jurassic Park. Los signos, por su parte, comprenden tanto los manuales de paleontología y los textos de divulgación científica como los cuentos y novelas de ficción. Los comics serían un ejemplo mixto, que combina las imágenes con los textos. Por último, en todas estas maneras de exhibición mencionadas abrevan las superproducciones cinematográficas que nos ofrecen los dinosaurios como entes a la mano en el mundo cultural circundante, muchas veces en una “cuasi” convivencia con los seres humanos. De estas múltiples maneras, el mundo jurásico se integra a nuestro mundo de la vida y lo amplía con nuevas perspectivas.

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Upper bound solutions of ring compression test

Upper bound solutions of ring compression test

In this paper a particularization of forging process is presented, studying the deformation of a ring specimen. Plastic forming is performed by means of the Upper Bound Theorem and the model of Triangular Rigid Blocks to calculate the minimal charge needed to deform the part. The establishing the part to deform an annular geometry is determined by the so-called Ring Compression Test under its canonical configuration, that allows assimilating to a plane strain process. A new perspective to calculate the neutral plane (radius at which the workpiece material flows in opposite directions) is proposed, a basic element in the solution of the problem.

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Upper extremity musculoskeletal pain among office workers in three Spanish speaking countries: findings from the CUPID study

Upper extremity musculoskeletal pain among office workers in three Spanish speaking countries: findings from the CUPID study

Regarding psychosocial working conditions, in Costa Rica and Nicaragua, over three-quarters of the participants reported working under time pressure as compared with only 54% in Spain; in Nicaragua, 40% reported lack of support from super- visors and coworkers, whereas fewer reported this exposure in Costa Rica (27%) and Spain (21%). There were also country differences in adverse health beliefs regarding UEMP. Twelve per cent of Costa Rican participants believed that upper limb pain is commonly caused by work, but in Spain this percentage was 20% and in Nicaragua 32%. Only 3% of participants in Costa Rica thought that physical activity should be avoided and that rest is needed to recover ( physical activity is harmful) from UEMP, but percentages were higher in Spain (10%) and Nicaragua (13%). This rank order was reversed with the highest proportion of participants in Costa Rica (22%) reporting that pain does not improve and that neglecting such pain is danger- ous ( poor prognosis) compared to 15% in Spain and 9% in Nicaragua. A somatising tendency was common, especially in Costa Rica and Nicaragua, where 61% and 58% of participants reported distress from two or more somatic symptoms versus only 40% in Spain. Finally, while in Spain, 24% participants reported intermediate/poor mental health, percentages were higher in Costa Rica (30%) and Nicaragua (36%).

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An upper atmospheric probe for auroral effects

An upper atmospheric probe for auroral effects

An electrically floating bare tether in LEO orbit may serve as upper atmospheric probe. Ambient ions bombard the negatively biased tether and liberate secondary electrons, which accelerate through the same voltage to form a magnetically guided planar e-beam resulting in auroral effects at the E-layer. This beam is free from the S/C charging and plasma interaction problems of standard e-beams. The energy flux is weak but varies accross the large beam cross section, allowing continuous observation from the S/C. A brightness scan of line-integrated emissions, that mix emitting altitudes and tether points originating the electrons, is analysed. The tether is magnetically dragged at nighttime operation, when power supply and plasma contactor at the S/C are off for electrical floating; power and contactor are on at daytime for partial current reversal, resulting in thrust. System requirements for keeping average orbital height are discussed.

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Upper limb rehabilitation with virtual environments: a review

Upper limb rehabilitation with virtual environments: a review

This article gives the results of a literature review process about upper limb rehabilitation based on virtual environments. The study borns of the following questions about the current state of knowledge in this subject: how virtual environments influence traditional rehabilitation?, Which performance metrics have been aplied in upper limb virtual rehabilitation? and which hardware devices are used in virtual rehabilitation? To answer the above questions a search for scientific articles was made in the search engine Google Scholar and databases PubMed, HINARI, ProQuest and Science Direct. The conducted review concluded that despite the existence of dozens of performance indicators to quantify the driving ability, there are no criteria to select a better index that best suits the objectives of a rehabilitation process.

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Through time Iberian Ursus spelaeus Ros.
Hein. cheek-teeth size distribution

Through time Iberian Ursus spelaeus Ros. Hein. cheek-teeth size distribution

and postcranel skeleton. But in spite of he published differences among average sizes of male and female cheek- teeth KURTEN (1995b), according to him such differen- ces were small, almost negligible, and in fact did not allow him to speculate about cave bear dentition size trends across Europe or and altitude-linked second upper molar size distribution. Furthermore KURTEN (1957) published a "case of darwinian selection in bears" based on size vartiation according to the age of death of cave bear. According to him it seemed that juvenile dead bears showed smaller teeth than adult dead bears did being this another restrictive factor on size comparison.

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Hemorragia digestiva alta no variceal asociada al uso del antiinflamatorios no esteroideos en Lima Metropolitana

Hemorragia digestiva alta no variceal asociada al uso del antiinflamatorios no esteroideos en Lima Metropolitana

CONCLUSIONS: In this study, the association between nonvariceal upper gastrointestinal In this study, the association between nonvariceal upper gastrointestinal hemorrhage and the use of NSAIDs was significantly high in Lima, specially in elderly hemorrhage and the use of NSAIDs was significantly high in Lima, specially in elderly population, and the peptic ulcer was the most common, particularly the gastric type. population, and the peptic ulcer was the most common, particularly the gastric type. KEY WORDS:

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Jurassic Pliocene biogeography: testing a model with velvet worm (Onychophora) vicariance

Jurassic Pliocene biogeography: testing a model with velvet worm (Onychophora) vicariance

Abstract: Summary paleomaps of global continental vegetation from the Jurassic through the Pliocene were prepared (based on the literature) and used to define an area cladogram. Bouvier's natural classification of velvet worms (phy­ lum Onychophora) was used to define a taxonomiclgeographic cladogram of onychophorans for all regions where they are found today. Both cladograms show the same sequence oC geographic vicariance. Thus, the paleogeographic model is supported by the taxonomic evidence. The paper includes a color atlas.

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Campaña alternativa transmedia para la película Jurassic world

Campaña alternativa transmedia para la película Jurassic world

Durante la premier de la película en diferentes salas de España (las más destacadas) se invitará a los asistentes a instalar, mediante wifi instalado en los cines, la aplicación creada. A su vez se le regalará unas gafas 3D de realidad virtual de cartón, basadas en la famosa marca de realidad virtual Oculus Rift y con un diseño que recuerde a los binoculares que aparecen en la primera entrega atrayendo asi a los coleccionistas. Una vez instalada la aplicación y colocado el dispositivo movil de los asistentes en las gafas de realidad aumentada, los azafatos del cine guiarán a los asistentes a través del pasillo hasta la sala de la premier, la cual será la más alejada de la entrada. En el transcurso del camino hacia la sala, los asistentes activarán la aplicación y gracias al sistema NFC (en su defecto códigos QR los que no dispongan de sistema NFC) y diferentes sensores NFC y códigos QR verán varias animaciones con dinosaurios en 3D, simulando la estancia en el propio parque “Jurassic World” y aportándoles una experiencia pocas veces antes vivida. Los asistentes irán por un pasillo central ambientado en el parque y delimitado a los laterales. Mediante la realidad aumentada esa delimitación real con cintas pasará a ser una delimitación que simule las vallas del parque, detrás de las cuales se encontraran las animaciones de los dinosaurios. A su vez, durante este recorrido los asistentes podrán hacer uso de una de las acciones que facilita la aplicación: hacer fotos o grabar un vídeo donde se puedan ver las animaciones de los dinosaurios dentro del cine.

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Sedimentary facies and ammonites relations between Arequipa and Tacna during Lower to Middle Jurassic

Sedimentary facies and ammonites relations between Arequipa and Tacna during Lower to Middle Jurassic

Currently, data showed in this report (stratigraphic columns, ammonites paleon- tology) (Fi. 2), corresponds to a set of information not yet publicated, obtained from INGEMMET field jobs. Data sets were taken from outcrops along coastal strip of southern Peru, in localities of Yura (Department of Arequipa) and ceros Palquilla and Pelado (Department of Tacna) (Fig. 1), within the Arequipa Mesozoic basin, southern Peru. Lower and Middle Jurassic sediments have been analizad in Arequipa (Yura) and Tacna (cerros Palquilla and Pelado) in terms of stratigraphy, sedimento- logy and paleontology. A taphonomic study of ammonites and its paleoenvironmen- tal and chronological implicances and has been related one to another.

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