Hervé F.

Universidad Andrés Bello | UNAB · School of Earth Sciences

The Antarctic Peninsula preserves geological evidence of a long-lived continental margin with intrusive, volcaniclastic and accretionary complexes indicating a convergent margin setting from at least the Cambrian to the Cenozoic. We examine the poorly understood units and successions from the Palaeozoic to the Early Mesozoic and develop detailed ki...

Late Paleozoic to early Mesozoic subduction complexes formed during the evolution of southwestern Gondwana and extensively crop out along the Chilean continental margin. Recent findings in northern Patagonia (40°–43°S) revealed that accretionary processes were active since the Devonian when enhanced lithosphere stretching in the forearc led to the...

In Memoriam

La geología de la porción occidental del Lago O'Higgins-San Martin (Fig.1A; 48° S) se encuentra dominada por sucesiones meta-sedimentarias que localmente alternan con menores cuerpos meta-máficos correspondientes al Complejo Metamórfico Andino Oriental (CMAO) (Hervé et al. 2008). Recientes estudios sobre el basamento de los Andes Patagónicos del Su...

The Cordillera de Darwin Metamorphic Complex (CDMC) comprise metamorphosed supracrustal rocks and metaplutonic suites which records a unique tectonic evolution among the metamorphic complexes of the southernmost Andes. The pressure (P) and temperature (T) conditions determined in garnet-bearing schists in the Central Domain of the CDMC indicate a c...

The Eastern Andean Metamorphic Complex (EAMC) in southwestern Patagonia (4°-52°S) is a 450 km long belt mainly composed by low-grade metasedimentary rocks of Upper Devonian-lower Carboniferous, and Permian-lower Triassic ages. Previous works have suggested a passive margin environment for the deposition of the protolith. The EAMC comprise scarce in...

The Andean basement of NW Patagonia contains remnants of a Devonian accretionary orogen that lasted for about 50 Ma. We present and review U-Pb geochronology, major and trace element geochemistry and O- and Hf-isotope analyses of zircon for Devonian igneous and metasedimentary rocks from the western edge of the North Patagonian Massif to the Pacifi...

Plain Language Summary Recent studies suggest that upper plate structure plays a key role during large earthquakes in subduction zones. This work presents the interpretation of 2D seismic velocity models and the analysis of seismic waves reflected in the deep zone of the continental crust, obtained along the south‐central Chilean subduction zone (b...

We present an interpretation of how natural geological and meteorological events influenced the cosmovision of the Mapuche people from south-central Chile. These events resulted from the geodynamic conditions and related processes occurring along the South American active continental margin and the climatic conditions in the region. Their influence...

In this work, we present the results of the first study which involves most of several cenozoic satellite plutons located in a 'back-arc' position in west Patagonia, south of the present Chile Triple-Junction. 4 plutons were studied in the northern tip, and 3 in the southern one. The petrographic and geochemical character of these plutons is differ...

The Eastern Andean Metamorphic Complex at Península La Carmela (48°50'S) consists of quartz-rich metaturbiditic sequences with tectonic slices of pillow metabasalt bodies deformed under low-grade metamorphic conditions. Previous and new detrital zircon U-Pb geochronological data from metasandstones indicate a preferred early Carboniferous maximum d...

We present the results of U-Pb zircon dating conducted using laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS), isotopic tracing analyses of Hf in zircon and Sr-Nd in whole-rock and whole-rock major oxides, and trace element abundances of 12 plutonic and volcanic rocks present on the Antarctic Peninsula. The dataset is present...

The metamorphosed mafic-ultramafic sequences of the Eastern Andean Metamorphic Complex outcropping in the Patagonian Andes are critical to disclose the late Paleozoic tectonic evolution of the southwestern margin of Gondwana. In the study area, mafic-ultramafic bodies are thrusted onto polydeformed metasedimentary rocks and intruded by the mid-Carb...

Late Triassic – Jurassic igneous rocks of the Antarctic Peninsula and Patagonia provide evidence for the evolution of the margin of southwestern Gondwana. We present new geochronological (LA-ICP-MS zircon UPb dates) analyses of 12 intrusive and volcanic rocks, which are complemented by geochemical and zircon isotopic (Hf) as well as whole rock isot...

Previously undated low-grade metamorphic rocks from the Puerto Cisnes-Queulat area (44°30’ S) contain detrital zircons of mid-Oligocene age (ca. 28 Ma). Their outcrops represent the easternmost occurrence of the late Oligocene to early Miocene marine volcano-sedimentary Traiguén Formation; previous correlation with the Paleozoic metamorphic basemen...

Previously undated low-grade metamorphic rocks from the Puerto Cisnes-Queulat area (44°30'S) contain detrital zircons of mid-Oligocene age (c. 28 Ma). Their outcrops represent the easternmost occurrence of the late Oligocene to early Miocene marine volcano-sedimentary Traiguén Formation; previous correlation with the Paleozoic metamorphic basement...

Geochronological record of plutonic activity on a long-lived active continental margin, with emphasis on the pre-Andean rocks of Chile

The sedimentology, petrography, and U–Pb dating of two Eocene volcaniclastic horizons of the Punta Torcida and Leticia formations, Austral basin, Tierra del Fuego, Argentina are interpreted and documented. The volcaniclastic deposits, pumicite breccia and tuffaceous sandstones, are formed by glass shards, plagioclase crystals, and pumiceous and lit...

U–Pb SHRIMP detrital zircon dating of ten samples of metamorphic “basement” rocks in north-central Chile and one granitic rock, improve knowledge of sedimentary, metamorphic and plutonic events in this segment of the Andean margin. The oldest possible sedimentation ages (Ordovician) come from a micaschist at Huentelauquén (477 Ma) and a granofels f...

The evolution of continental crust in convergent margins can be explored in southernmost South America (54-56°S). Plutonic rocks of the Fuegian Batholith and the rear-arc satellite Ushuaia Pluton were emplaced within the magmatic arc and the Fuegian fold-and-thrust belt, respectively. They record subduction zone processes in two distinct tectonic s...

Triassic orthogneisses of the Antarctic Peninsula provide evidence for the Palaeozoic and Mesozoic geological evolution of southern Gondwana within Pangaea. These rocks are sporadically exposed in southeastern Graham Land and northwestern Palmer Land, although reliable geochronological, geochemical and isotopic data are sparse. We combine new geoch...

Se presentan resultados preliminares de un estudio de ASM realizado en el Fiordo Reñihue, ubicado al este de la Isla Grande de Chiloé. Se recolectaron 18 sitios en rocas metavolcánicas y metasedimentarias de edad Devónico y en rocas intrusivas correspondientes al Batolito Norpatagónico de edad Neógeno. Se lograron obtener fábricas magnéticas bien d...

Este es un póster sobre lo que realicé en mi Memoria de Título. Contiene de forma muy resumida, algunos de los resultados destacables y/o notables de mi tesis.

Early Cretaceous evidence for Atacama Fault activity

Since the 1990s, the main international organizations dedicated to the conservation of nature and geosciences have included geoconservation among their areas of research. Gradually but increasingly, Chilean institutions linked to geology are working in this line, with the common hypothesis being that the country has a significant geoheritage. Howev...

This paper addresses the Jurassic-Cretaceous stratigraphic evolution of fore-arc deposits exposed along the west coast of the northern Antarctic Peninsula. In the South Shetland Islands, Upper Jurassic deep-marine sediments are uncomformably overlain by a Lower Cretaceous volcaniclastic sequence that crops out on Livingston, Snow and Low islands. U...

This paper addresses the Jurassic–Cretaceous stratigraphic evolution of fore-arc deposits exposed along the west coast of the northern Antarctic Peninsula. In the South Shetland Islands, Upper Jurassic deep-marine sediments are uncomformably overlain by a Lower Cretaceous volcaniclastic sequence that crops out on Livingston, Snow and Low islands. U...

Triassic orthogneisses of the Antarctic Peninsula provide evidence for the Palaeozoic and Mesozoic geological evolution of southern Gondwana within Pangaea. These rocks are sporadically exposed in southeastern Graham Land and northwestern Palmer Land, although reliable geochronological, geochemical and isotopic data are sparse. We combine new geoch...

This study explores the use of stalagmites to record extreme coastal conditions with the aim for a better understanding of these events and their periodicity. This work applies a multi-proxy study on a speleothem from a coastal cave developed in schists under a Miocene marine terrace in Central Chile, a very unusual context. An innovative approach...

Resumen. En la isla Kent afloran esquistos micáceos con fengita y clorita y esquistos con granate, estos últimos como pseudomorfos reemplazados completamente por clorita. Se registran tres eventos de deformación (D1, D2, D3). El evento D1 está relacionado con el desarrollo de la foliación S1 de plano axial, con pliegues isoclinales en bandas de cua...

Geochemistry of Devonian magmatism in the Coastal Ranges of south Chile.

Geochemistry of Devonian magmatism in south Chile

Para una estrategia nacional de geoconservación, se requiere determinar cuáles y cómo son, dónde están, y qué valor tienen los principales elementos del patrimonio geológico. Esto implica el desarrollo de un inventario nacional de geositios. En Chile se avanza en esta tarea desde hace más de una década; por medio de la SGCh, del Servicio Nacional...

Previous work has shown that Devonian magmatism in the southern Andes occurred in two contemporaneous belts: one emplaced in the continental crust of the North Patagonian Massif and the other in an oceanic island arc terrane to the west, Chaitenia, which was later accreted to Patagonia. The country rocks of the plutonic rocks consist of metasedimen...

La geodiversidad de la comuna de Puerto Varas, está constituida principalmente de rocas plutónicas de edades cretácicas y miocenas del batolito nor-patagónico junto con depósitos volcánicos y glaciares del Holoceno-Pleistoceno que constituyen una variedad geológica excepcional. Además, tanto el alzamiento de las rocas plutónicas, el emplazamiento d...

U-Pb SHRIMP zircon detrital ages as young as late Oligocene were obtained from two metamorphic rocks -a schist and a metaconglomerate- from the North Patagonian Andes of Aysén at the latitude of Isla Magdalena, and in a paraconglomerate sample belonging to the La Junta Formation. The maximum possible sedimentation age obtained precludes the correl...

Better constrained pressure-temperature (P-T) histories of metamorphic complexes along the Andean continental margin are important for understanding the late Paleozoic and Mesozoic tectonic evolution of the southwestern margin of Gondwana. The Mejillones Metamorphic Complex of the northern Chilean Coastal Cordillera is composed of two tectonic unit...

New sensitive high-resolution ion microprobe (SHRIMP) U-Pb detrital zircon ages from Cambrian to Permian−Carboniferous siliciclastic units in the Ellsworth Mountains constrain their provenance and maximum depositional age, as well as providing key information as to the tectonic evolution of a problematic region. The Cambrian Heritage Group was depo...

The genesis of Permian magmatism in southern South America is actively debated, particularly in relation to the origin of Patagonia. U–Pb zircon ages of c. 255 Ma for igneous rocks from the basement of Tierra del Fuego are the first evidence for southerly prolongation of this magmatism. Zircon in these rocks has εHft values <−1 and δ18O > 7.4‰, ind...

Serpentinites and fresh or partially serpentinized harzburgite crop out in the western slope of the North Patagonian Andes of continental Chiloé (41°44'-42°12'S). These rocks are spatially associated with low-grade metamorphic rocks containing Cenozoic detrital zircons. The metamorphic rocks, together with Devonian metasediments, have been mapped p...

Exiliado de su natal Polonia, hoy Lituania, hubo de abandonar sus estudios universitarios en Vilnius, para continuarlos en la Escuela de Minas de Paris. En 1838, fue contratado por el gobierno de Chile, para enseñar mineralogía en la ciudad de Coquimbo. Sus enseñanzas de mineralogía se caracterizaron por una fuerte componente práctica en un laborat...

El Profesor Johannes Brüggen Messtorff (1887-1953) fue quien, con el libro Fundamentos de Geología de Chile (1950), trazó una primera visión integrada de la geología chilena, que refunde el conocimiento adquirido en 40 años de investigación. A ello deben agregarse unas 60 publicaciones sobre la geología y recursos naturales de Chile y textos didáct...

Metasedimentary rocks in the Antarctic Peninsula and south-western Patagonia record detrital zircon evidence for significant Permian magmatic events along the Palaeo-Pacific margin of south West Gondwana. However, it is unclear where and how this magmatism formed due to the lack of outcropping Permian igneous sources at similar latitudes. Combined...

The petrology and geochronology of Paleozoic and Mesozoic metamorphic and ophiolitic complexes in southern Patagonia constrain the evolution of magmatic belts, marginal basins, and continental fragments that once formed part of the peripheral realm of the southwestern Gondwanan margin. The upper Paleozoic metasedimentary rocks exposed along the eas...

Supposed or potential Devonian igneous rocks in the accretionary complex of southern Chile were investigated using sensitive high-resolution ion microprobe U–Pb dating of zircon, with Hf-and O-isotope analyses of selected grains. Ages of 384 ± 3 and 382 ± 2 Ma are confirmed for two igneous bodies (another having been previously dated at 397 ± 1 Ma)...

The southernmost Andes of Patagonia and Tierra del Fuego present a prominent arc-shaped structure: the Patagonian Bend. Whether the bending is a primary curvature or an orocline is still matter of controversy. New paleomagnetic data have been obtained south of the Beagle Channel in 39 out of 61 sites. They have been drilled in Late Jurassic and Ear...

The Chilean margin has been used as the model of an ocean-continent convergent system dominated by compression and active mountain building as a consequence of the strong mechanical coupling between the upper and the lower plates. The Andean Cor-dillera, however, shows evidence of alternating phases of compressional and extensional deformation. Vol...

Resumen The Andean Cordillera shows evidence of alternating phases of compressional and extensional deformation. Volcano-sedimentary marine strata in the Aysén region of southern Chile were investigated to better understand the causes of extensional tectonics and crustal thinning that occurred in the Andean orogeny as these deposits constitute the...

Supposed pre-Mesozoic igneous and metamorphic rocks from northern Chile are reviewed in the light of twenty-one new SHRIMP U-Pb zircon age determinations. Metamorphic rocks from the precordillera upthrust belt mostly show a wide spectrum of zircon ages, indicating derivation from sedimentary protoliths. Youngest detrital zircon ages (i.e., maximum...

Middle Devonian calk-alkaline igneous bodies intruding the late Paleozoic basement of Los Lagos region (south of 40°S) are strong evidence to support the existence of an active margin on this segment of SW Gondwana during the Devonian. This magmatism has a mantelic isotopic affinity in western slope of the Andes with a Late Neoproterozoic (0.61 Ga)...

Fossiliferous marine deposits dated ca. 9500 yrs BP crop out at the locality of Huinay, Region de los Lagos, southern Chile. Several sedimentary horizons containing fossil bivalves in living position, as well as plant fragments, crop out in cliffs at the northern part of the mouth of rio Loncochaihua, up to several meters above present sea level. T...

Chile es un país exótico, con una variedad única de paisajes que son una fuente importante de conocimiento y es vital su conservación como Patrimonio Geológico para el desarrollo de otras actividades relacionadas como estudios científicos, educación, divulgación y turismo. En la actualidad existen 66 geositios reconocidos por la Sociedad Geológica...

The Carboniferous-Triassic Trinity Peninsula Group is a metasedimentary sequence that crops out widely in the northern Antarctic Peninsula. These are some of the most extensive outcrops in the area and hold the key to evaluating the connections of the Antarctic Peninsula in Gondwana; however, they are still poorly understood. Herewe present our pro...