The study on Silurian-Devonian conodonts from the Precordillera has shown a significant increase in the last 5 years. In the new conodont collections, particular specimens of Ozarkodina were obtained from the middle and upper parts of the Los Espejos Formation in the Talacasto region. The taxonomic study allows us to propose a new species of the genus Ozarkodina, named Ozarkodina huenickeni sp. nov

The emplacement of lava flows into poorly consolidated sediments during volcanism can lead to a wide range of lava-sediment interaction processes. Understanding these processes and their products is critical for appraising reservoir quality and connectivity in both intra- and sub-volcanic prospectivity settings. This study investigates the nature of lava-sediment interactions during the onset of magmatism

This paper presents new taxonomic reports and biostratigraphic inferences based on ostracods in the basal section of the cored well UFRJ-2-LRJ-01-SE, perforated in the Votorantim quarry, Sergipe-Alagoas Basin, Brazil. The studied material comprised 44 samples in the range 438.65 to 315.30 m, identifying 52 species of ostracods distributed in 31 genera and 16 families. Five new species are proposed:

The tragic fire at the National Museum (Brazil) in September 2018 caused invaluable losses to South American natural and cultural heritage. However, previous visits to the paleontological collection generated photographic and descriptive records of mammalian fossil specimens from the Pleistocene of Brazil. Thus, it was possible to redescribe and revise the taxonomy of Cervidae fossils from two important

The Cambaí Complex TTG-like rock assemblage representing a Neoproterozoic juvenile magmatic arc is part of the São Gabriel Terrane that crops out in the SW domain of the Dom Feliciano Belt in S-Brazil. Geochemistry of dioritic, tonalitic, trondhjemitic, and granodioritic rocks of this complex indicate their low-medium-K calc-alkaline geochemical affinity being metaluminous and with fractional crystallization

The Piedras de Afilar Formation (PAFm) is a late Neoproterozoic sedimentary succession autochthonous to the Tandilia Terrane, part of the Río de la Plata Craton. It overlies with erosional unconformity a Paleoproterozoic igneous and metamorphic basement. According to facies analysis and lithostratigraphy, the PAFm is divided into three members for which detailed petrography, X-ray diffractometry and

Ophiomorpha nodosa Lundgren1891 is described from Puente de Pascua Formation Late Pleistocene of northeastern Buenos Aires province. The pelletal morphology and the base of ramifications of O. nodosa burrows are compared with mid-Holocene, Late Pleistocene Pehuen-Có locality and southern Brazil records. The preservation between sites differs in the degree of erosion and weathering, in situ or ex situ

Physically based models have been widely used around the world to study landslide occurrence. The accuracy in a physically based landslide susceptibility/hazard assessment depends mostly on the input parameters. In this research study, three physically based models' applicability and performance were assessed using deterministic and probabilistic approaches. It was carried out in a data-scarce environment:

The Cenomanian-Turonian Eagle Ford Formation is a widespread organic-rich mudrock in Texas and northern Mexico. The economic significance of this unit for oil and gas production in USA has led to numerous investigations documenting its lithological and geochemical variability. Comparatively little is known about facies distribution and source rock potential of this unit in Mexico. Here, we studied

Carbonate rocks occur in Brazil under diverse climatic and environmental conditions, and therefore are of great importance for pedological studies. The northwest region of the State of Rio de Janeiro, Brazil, is composed of calc-silicate rocks and marbles that occur under tropical climate with a long period of water deficit, which provides conditions for peculiar pedogenesis. The objective of this

The participation of mantle-derived magmas, especially hydrous basaltic liquids, in the evolution of granitic belts in both orogenic and post-collisional environments is crucial to evaluate both mantle and crustal evolution, as well as the material transference processes between these two reservoirs. Besides, this transition in the geodynamic context creates specific conditions, promoting the generation

Rocks of the Vazante Group in the Morro Agudo region (SE-Brazil) integrate a thick clay-carbonate sequence composed of twelve sedimentary facies and four facies associations (FAs), deposited in a mixed marine passive margin environment. This work carried out systematic isotope analyses of δ13C and δ18O on the two upper stratigraphic units of the Vazante Group (Morro do Calcário and Serra da Lapa formations)

A bauxite-bearing lateritic profile, developed along a borehole within the supergenic Fe-deposits of the Carajás Mineral Province in Brazil, is investigated after its textural aspects, mineralogy, and geochemistry. Petrographic studies, XRD mineralogical analysis, SEM-EDS, and whole-rock chemistry were used to study selected samples. The 156 m depth borehole is composed of basaltic andesite at the

The dicynodont fauna of South America is comprehensively reviewed. Permian South American dicynodont body fossils are known only from the Rio do Rasto Formation of southern Brazil, and include a specifically uncertain representative of the trans-Gondwanan genus Endothiodon and the endemic Rastodon procurvidens. The majority of known South American dicynodonts are Triassic kannemeyeriiforms, with numerous

Guallatiri volcano is an active stratovolcano located in the Arica y Parinacota Region of northern Chile. It belongs to the Central Volcanic Zone (CVZ) of the Andean range and is the youngest and southernmost volcano of the Nevados de Quimsachata volcanic chain. Guallatiri is an ice-capped volcano considered the third-highest risk center in northern Chile with a current activity characterized by two

The objective of this work was to characterize the spectral responses of soil and plant indicators utilizing the Soil-Adjusted Vegetation Index (SAVI) and Leaf Area Index (LAI) in areas under the cultivation of ‘Orelha de Elefante Mexicana’ forage cactus (Opuntia stricta (Haw.) Haw.) and ‘Miúda’ (Nopalea cochenillifera (L.) Salm-Dyck) in Brazilian semi-arid region and to establish a model for characterizing

The Xingu River is an important tributary of the Amazon River, contributing 5% of its total water discharge. Nevertheless, it does not contribute substantially to the sediment load. The lower reach of the Xingu River forms a ria, a result of the Holocene sea-level rise. The Xingu is also classified as a tidal river, with tides >1 m at its confluence with the Amazon River. This study evaluated the morphology

Sauropodomorpha is the first major dinosaurian group that radiated during the Triassic. During this time the group underwent major changes in body plan, including the acquisition of features related to herbivory, large body size, and quadrupedality. By the end of the Late Triassic, approximately 30 million years after the origin of dinosaurs, sauropodomorphs predominated the niches of large herbivores

This study aimed to test the use of inland sponge spicules as proxy data for a Holocene paleoenvironmental reconstruction of the Trairí River valley, in the state of Rio Grande do Norte, in Northeast Brazil. Spicules were recovered from sediments from two core samples obtained from Lake Fumo and Lake Urtiga, at depths of 0.60 m and 0.96 m, respectively. The following analyses were carried out: phytolith

Two new hemipteran taxa are described: Dysmorphoptiloides losrastrosensis sp. nov. and Gualoscarta obscura gen. et sp. nov. (Auchenorryncha: Dysmorphoptilidae). Likewise, we report the first specimen of a corixid (Heteroptera: Nepomorpha) from the Triassic of Gondwana. The fossil material studied in this paper comes from the Gualo locality, the Carnian Los Rastros Formation, Ischigualasto-Villa Unión

Results from an engineering geological mapping study of the urban area of Ouro Preto in the state of Minas Gerais, Brazil, are presented. The goal of the study was to verify the efficacy of procedures, methods and classification schemes based on engineering geological mapping principles to generate data and maps for urban planning, restructuring (rehabilitation) and engineering projects. The study

A lithofacial and palynological study was carried out on the Cañadón Seco Formation in the La Frieda Oeste x-1 well (Golfo San Jorge Basin). According to sedimentological characteristics of the core four main litofacies lithofacies are defined: 1. Cross-bedded sandstones, 2. Interlaminated fine-grained sandstones and mudstones, 3. Shales, and 4. Muddy tuff. The cross-bedded sandstones correspond to

The Tacaná Volcanic Complex (TVC) is an active volcano, located on the border between Mexico and Guatemala, in the westernmost part of the Central American Volcanic Arc. The TVC has produced effusive and explosive activity during the past 300 ka through the emplacement of lava flows, pyroclastic deposits, debris avalanches and lahars. During the last 10 ka, at least 11 eruptions have occurred, with

The geological record of late Paleozoic rocks is ubiquitous along the north to central Chile (21°–33° S). The most accepted evolutionary model proposes that the SW-Gondwana margin in northern Chile (north of 28° S) evolved from a passive margin setting in the Devonian to late Carboniferous that switched to an active margin setting during the early to late Carboniferous and continued during the Permian

This paper presents a synthesis of the advances in the geologic knowledge of the late Paleozoic basins of southern South America during the last decade. The information is focused on: i) progress in paleogeographic models and new perspectives, ii) distribution of late Paleozoic glacial deposits, sedimentary models and identification of discrete events, iii) paleoclimatic evolution and pieces of evidence

The Sierra de Aguirre Fm. in southern Uruguay constitutes one of several post-collisional basins of the Dom Feliciano Belt, preserving an important volcanic record associated with this protracted stage of the orogenic system. This study combines new stratigraphic, structural, geochronological and isotopic geochemical results, together with a reassessment of the available geochemical data, to present

New isotopic and geochemical data for the Paleo- Meso- and Neoproterozoic metasedimentary cover of the southern Dom Feliciano Belt (Brasiliano/Pan-African) are presented and evaluated combined with published information. Whole-rock major and trace element geochemistry indicates that the dominant source for all the units was the upper continental crust. The geochemistry is similar even for late Ediacaran

Anisotropy of magnetic susceptibility (AMS) has been used as an important tool to study magnetic fabrics and as a basis of interpretation of depositional conditions and post-depositional processes in sedimentary successions. This contribution presents results of standard AMS and magnetic mineralogy analysis performed in core samples from the PANG 0003 well, located at the Claromecó Basin, Buenos Aires

We present the ichnological characterization on marine gastropod shells from Late Pleistocene, mid-Holocene and modern beaches at 5 sampling sectors along the southern Golfo San Jorge, a key area at central Patagonia in terms of geological, physical and biological features of the southern Southwestern Atlantic margin. Based on bioerosion recovered in 579 gastropod shells (22% showing bioerosion and

The Yacoraite Formation is a worldwide known unit due to the diversity and abundance of vertebrate ichnological record. The complex tectono-sedimentary evolution related to the Andean Cycle generated high dip angles of bedding and, consequently, large tracksites are not easily accessible, making hard the ichnological analysis. Here, we describe a new tracksite named “La Banderita”, near Juella town

Rhyolites compose an important record in the volcanic history of Earth, with significant occurrences in volcanic arcs, large igneous provinces and post-collisional terranes, often associated with explosive events. In several geologic provinces, rhyolites dominate as the most expressive geologic units (e.g., Silicic Large Igneous Provinces - SLIPs). Despite their importance, several aspects related

The Trans-Mexican Volcanic Belt (TMVB) is a calc-alkaline volcanic arc cut by different active crustal fault systems that have originated several destructive historical earthquakes. Located in the central part of Mexico this region offers exceptional climatic, and fertility of soil conditions, which is the reason why more than 50% of the Mexican population now live here, increasing the seismic risk

One of the main characteristics of the orogenic systems formed during the assembly of southwestern Gondwana in the Late Neoproterozoic is the widespread granitic magmatism. The Florianópolis Batholith in South Brazil is an excellent example of this process, as it is part of a ca. 1,400 km long intrusive association that is a key unit in the reconstruction of the paleogeography of Gondwana on both sides

During the last decades, tectonic models provided new insight into the evolution of the Luis Alves, Curitiba, and Paranaguá terranes, which are all limited by thrust and transpressive shear zones, nowadays outcropping only as deep crustal horizons and presenting poorly known lateral displacements. An essential puzzle piece to understanding the juxtaposition processes and evolution of these blocks in

New fossil plants are described from the Ischichuca Formation (Middle?–Late Triassic), La Rioja province, northwestern Argentina. A systematic description of Heidiphyllum leaves, ovulate structures of Dordrechtites and undetermined conifer wood is provided. This is the first description of these elements for the Ischichuca Formation, and the first illustration of Dordrechtites from South America, thus

The southern Argentine Continental Margin hosts the Tierra del Fuego Submarine Canyon System, located in the northwestern Scotia Sea, and formed by 4 main canyons: Valentín, Sloggett, Nueva Canyon, and Wollaston. This region is especially interesting due to its complex tectonic setting and its proximity to the polar regions where intense bottom currents associated with the Argentine Contourite Depositional

Advanced techniques in the recognition and classification of seismo-volcanic events are transcendental when studying active volcanoes, not only for their importance as an accurate real time seismic monitoring procedure but also for the use of their results in modeling the dynamics of the volcanic environment. It is well known that real time seismic monitoring deals with such a large amount of data

Azufral volcano is an active composite volcano located in SW Colombia, whose edifice is mostly formed by pyroclastic deposits and lava flows. Recent road works in the region, NE of the volcano, revealed unknown deposits, one of them related to a debris avalanche event. This deposit, herein named San Roque debris avalanche deposit, outcrops along a 13 km section in the road Túquerres - Samaniego. Using

A new cyanobacterium, Patagonifilum jurassicum nov. gen. et sp., is structurally preserved in Late Jurassic hydrothermally influenced siliceous chert from the Deseado Massif, Patagonia, Argentina. The cyanobacterium occurs in the form of loosely to densely spaced, heteropolar filaments (up to 4.5 μm wide) that form turf-like stands, or spherical to hemispherical colonies on different substrates, usually

Proterozoic Silicic Large Igneous Provinces (SLIP) are part of the geological inventory since they record the planet's thermal evolution. The Amazonian Craton hosted the poorly understood Uatumã SLIP, which formed ca. 1.88 Ga years ago. The so-called Uatumã magmatism represents the volcanic products of SLIP. This magmatism also refers to specific stratigraphic units, such as the Uatumã, Iriri, and

This study provides new insights about mechanisms of synkinematic interplay between dyking emplacement and ductile narrow shear zones formation in the Sierra Chica de Córdoba. A detailed analysis of structural, microstructural, geometric-scaling and geochronologic data is performed in order to demonstrate the important role that minor and meso-scale felsic dykes played in the formation of paired shear

Pululahua is a potentially active dome complex located 15 km north of Quito. It is composed of sixteen dacitic-andesitic lava domes located inside and around a semi-rectangular depression. We divide its eruptive history into: (1) a first member characterized by effusive lava dome growth and collapse (Units I and II, >18–12 ka), (2) a second member consisting of at least four explosive eruptive phases

The scope of the original manuscript of Heilbron et al. (2020) was to present a geological, geochemical, isotopic, petrologic and geochronological synthesis regarding the Neoproterozoic (850–530 Ma) Ribeira orogenic belt. The magmatic arc-related associations of this orogenic belt were developed during the amalgamation of West Gondwana and display accretionary and collisional magmatic arc signatures

In this contribution we outline the outstanding attributes and inferred depositional controls for dark mudstones of the Alicia Formation (~570 Ma) in order to reveal the intrinsic characteristics of unknown Ediacaran marine depositional conditions into the basin. The Alicia Formation represents a continuous and undeformed ~150 m thick sequence in which nine siliciclastic lithofacies were accumulated

New zircon and apatite fission-track analyses and aluminium in hornblende thermobarometric data are presented from Cretaceous and Triassic plutons situated along an east-west transect across the Central Cordillera, the Cauca Romeral Fault System and the eastern slopes of the Western Cordillera in the Colombian Andes. The results are combined with published apatite (U–Th)/He ages revealing three episodes

A new fossil record of early Mississippian marine faunas is described from the Agua de Lucho Formation in the Sierra de las Minitas (La Rioja province, Río Blanco Basin, western Argentina). Considered Tournaisian in age based on local palynological data and biostratigraphic correlations, this faunal record is notably diverse associated with glacially influenced deposits, in contrast with other early

We present new data on the Vichigasta Carboniferous paleovalley, a glacial trough crucial to understand the type of glaciation that affected western Gondwana during the Late Paleozoic Ice Age (LPIA). The filling of this paleovalley starts soon after the mid-Carboniferous glacial peak. Stage I represents pro-glacial lacustrine deposits with outwash, glacially rafted dropstones, mass transport deposits

The taphonomy of a partial skeleton of the fur seal Arctocephalus australis from the mid-Holocene of Miramar (southern Buenos Aires province, Argentina) comprising most of both hindlimbs and some vertebral elements is herein described and discussed. The main axis of the long bones is oriented perpendicular to the coastline, flexed and slightly disarticulated, while the vertebrae are somewhat arched

The oceanic basins are dotted by seamounts, guyots and islands formed by the mantle plumes and oceanic lithosphere interaction. These plumes are responsible for several intraplate volcanisms such as the Emperor-Hawaii Chain in the Pacific Ocean with a remarkable bend at ca. 47 Ma. Comparatively, the Vitória-Trindade Ridge (VTR) in the South Atlantic Ocean was also generated by a mantle plume and in

We studied fossil woods from Matasiete and Castillo Formations (Aptian–Albian) for the first time. The woods, preserved in fluvial channel and floodplain deposits, have anatomy consistent with the fossil-genus Brachyoxylon Hollick and Jeffrey. Specimens from Castillo Formation have poorly distinct growth ring boundaries, exclusively uniseriate with a mixed arrangement intertracheary radial pitting

The Mexican horse Equus conversidens is a representative member of the Quaternary North American megafauna. Systematics, phylogeny, and stable isotope ecology of this species are known in some detail, although information regarding population ecology is unexplored. Numerous fossil remains (isolated teeth, mandibles, skulls, and postcranial elements) of this horse have been collected from Pleistocene

A dataset with information on samples of gabbro, charnockite, gneiss, granite, basalt, and sandstone-derived iron lateritic duricrusts, concretions, nodules, and soils was analyzed to address the multi-element chemical composition, background values, scavenger trace elements in Fe oxyhydroxides, parent rock inheritance, and weathering effect on Pb isotopes. Tropical weathering causes high mass loss

Four major igneous suites with different geochemical characteristics are identified in the accretionary complex of the Pampean orogeny from the southern Sierras de Córdoba, Argentina. Crystallization ages of gabbroic and trondhjemitic plutonic rocks are Early to Middle Cambrian. The plutonic suites include mafic to intermediate alkaline OIB-like rocks, mafic tholeiitic N-MORB rocks, transitional mafic

The southeastern Brazilian passive margin records a complex post-rift evolution, with two parallel high-elevation features formed after the opening of the South Atlantic. We applied apatite fission track (AFT) and U–Th/He (AHe) low temperature thermochronology to constrain the thermo-tectonic history of the Serra do Mar escarpment in the area of Rio de Janeiro state. New AFT central ages for basement