Gustavo Vergani - Academia.edu (original) (raw)
Papers by Gustavo Vergani
PLOS ONE, 2024
Chitinozoans recovered from one section of the Middle Devonian Los Monos Formation in the TCB X-1... more Chitinozoans recovered from one section of the Middle Devonian Los Monos Formation in the TCB X-1001-Tacobo borehole, sub-Andean basin of Bolivia, have been analysed. Eleven from the eighteen processed cutting samples yielded specimens that allowed taxonomic study. Eleven genera and thirty-five chitinozoan species were identified from the Los Monos Formation with four of them recorded for the first time in Western Gondwana. Ancyrochitina biconstricta, Ancyrochitina parisi, Angochitina galarzae and Ramochitina boliviensis are among the most relevant taxa restricted to Western Gondwana that support the affinity with this paleocontinent. One new species, Lagenochitina tacobensis sp. nov. is described, and Ramochitina candelariaensis sp. nov. (n. n.) is formally erected. The chitinozoan assemblage reinforces the late Eifelian-middle Givetian age previously proposed by organic-walled phytoplankton and miospores for this section of the TCB X-1001-Tacobo borehole. A new local chitinozoan biozonation based on the chitinozoan assemblages is proposed and a revision of the current chitinozoan biozonation for Western Gondwana and Bolivia is recommended.
PloS one, Apr 9, 2024
Chitinozoans recovered from one section of the Middle Devonian Los Monos Formation in the TCB X-1... more Chitinozoans recovered from one section of the Middle Devonian Los Monos Formation in the TCB X-1001-Tacobo borehole, sub-Andean basin of Bolivia, have been analysed. Eleven from the eighteen processed cutting samples yielded specimens that allowed taxonomic study. Eleven genera and thirty-five chitinozoan species were identified from the Los Monos Formation with four of them recorded for the first time in Western Gondwana. Ancyrochitina biconstricta, Ancyrochitina parisi, Angochitina galarzae and Ramochitina boliviensis are among the most relevant taxa restricted to Western Gondwana that support the affinity with this paleocontinent. One new species, Lagenochitina tacobensis sp. nov. is described, and Ramochitina candelariaensis sp. nov. (n. n.) is formally erected. The chitinozoan assemblage reinforces the late Eifelian-middle Givetian age previously proposed by organic-walled phytoplankton and miospores for this section of the TCB X-1001-Tacobo borehole. A new local chitinozoan biozonation based on the chitinozoan assemblages is proposed and a revision of the current chitinozoan biozonation for Western Gondwana and Bolivia is recommended.
The objective of this work is to discuss the paleoenvironment and age of the Los Monos Formation,... more The objective of this work is to discuss the paleoenvironment and age of the Los Monos Formation, in outcrop and subsurface, along a regional transect (west-east) in the southern sector of the Tarija basin. The lithofacies and ichnofacies of the Alarache, Angosto del Pescado and Balapuca outcrops and core-intervals of the Aguas Blancas xp-13, Ramos x-12, Tartagal x-1 and Tonono x-1 boreholes were analyzed. The definition of lithofacies and ichnofacies allowed us to interpret a shallow to outer shelf paleoenvironment (from the offshore-transition, offshore and shelf). Towards the top of the Tonono Formation, the equivalent of the Los Monos Formation in the Chaco-Salteño was defined as a brackish-waters marginalmarine paleoenvironment. The mineralogy of the mentioned sections plus the Vespucio x-1 borehole was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), thus the majority elements in clay minerals were also determined from EDAX. Authigenic and detrital c...
The Neuquen basin of west-central Argentina is a triangular-shaped depocenter covering more than ... more The Neuquen basin of west-central Argentina is a triangular-shaped depocenter covering more than 160,000 km2. It accounted for about 44% of Argentinian oil production in 1992. The tectonic evolution spans about 220 m.y. of subsidence which preserves a Mesozoic-Cenoz oic basin fill at least 7,000 m thick. Initial rifting in the Triassic is characterized by basementinvolved normal extensional fault s which bound discrete half grabens separated by transfer faults. From the Aalenian onward, fault-controlled subsidence was replaced by regional subsidence and the rifts and their intervening highs were yoked together in a broad post-rift basin. The stratigraphic record is punctuated by several unconformities which reflect intermittent subsidence as well as multiple episodes of structural inversion. From the Callovian onward, the Neuquen basin was subjected to periodic inversion of earlier extensional structures which modified the shape of the basin and rejuvenated fringing sedimentary sour...
In the southern sub-Andean region of Bolivia, most of the structurally controlled hydrocarbon tra... more In the southern sub-Andean region of Bolivia, most of the structurally controlled hydrocarbon traps are related to the development of the Andean fold-and-thrust belt. The present study analyzed the structure and the hydrocarbon accumulations at the south sub-Andean “wedge-top.” The structural decoupling in the allochthonous section is characterized by two vertical overlapping structural levels, and the general geometry is defined as a trailing imbricate fan system. Backthrusts, lateral ramps, and tear faults are associated with the shallow structural level. They can act either as barriers or as secondary migration pathways for hydrocarbon accumulations. Related traps show three- and four-way dip closure, but only the latter were productive. The Curiche and Tajibo gas fields are two examples that produce from Cenozoic units in this structural domain. The deeper structural level is defined by thrust sheets with no forelimb development, generating three-way dip closure traps. The Tacob...
Revista de la Asociaci�n Geol�gica Argentina, 2016
AAPG Bulletin, 1995
Tectonic Evolution and Paleogeography of the Neuquén Basin, Argentina GD Vergani Perez Companc Ne... more Tectonic Evolution and Paleogeography of the Neuquén Basin, Argentina GD Vergani Perez Companc Neuquén, Argentina AJ Tankard Tankard Enterprises Calgary, Alberta, Canada HJ Belotti HJ Welsink Perez Companc Neuquén, Argentina Abstract The tectonic evolution of ...
Se presenta una descripcion e interpretacion de las estructuras de deformacion en las diferentes ... more Se presenta una descripcion e interpretacion de las estructuras de deformacion en las diferentes posiciones estructurales (flanco, charnela) del anticlinal Tin Tin, un pliegue con nucleo de basamento formado durante la contraccion cenozoica andina en el sector suroeste de la Cordillera Oriental del noroeste argentino. La gran mayoria de las estructuras son pliegues asociados a fallas inversas de bajo angulo con transporte occidental que en conjunto afectan a todas las unidades del Grupo Salta, y producen un engrosamiento de la cobertura sedimentaria. La cinematica de las estructuras coincide con la del anticlinal principal (vergencia y transporte occidental) y en general presentan su misma orientacion NNE-SSO. En menor medida se encuentran fallas de rumbo con alta inclinacion y orientacion oblicua a la del anticlinal. Las relaciones geometricas entre las estructuras en la cobertura sedimentaria indican una cronologia que sugiere una deformacion de piel fina relativamente previa al a...
Ameghiniana, 1995
... Su presencia con-firmaría con mayor fuerza aún la edad cretácica asig-nada al Horizonte Calcá... more ... Su presencia con-firmaría con mayor fuerza aún la edad cretácica asig-nada al Horizonte Calcáreo Dolomítico y las Margas Multicolores". Es muy posible que Reig haya opinado de esa manera por cuanto asoció los peces con formas cretácicas (o supuestamente cretácicas ...
UNIRED: PROYECTO PADRINAZGO PUBLICACIONES PERIODICAS ARGENTINAS. Título (A): Cuencas del extremo ... more UNIRED: PROYECTO PADRINAZGO PUBLICACIONES PERIODICAS ARGENTINAS. Título (A): Cuencas del extremo austral de la placa sudamericana: diferencias, conexiones y una historia en común, pp. 201-206. Autor Personal ...
Journal of South American Earth Sciences, 2010
The common elements and differences of the neighboring Austral (Magallanes), Malvinas and South M... more The common elements and differences of the neighboring Austral (Magallanes), Malvinas and South Malvinas (South Falkland) sedimentary basins are described and analyzed. The tectonic history of these basins involves Triassic to Jurassic crustal stretching, an ensuing Early ...
La Formacion Yacoraite esta constituida por rocas carbonaticas de color gris blanquecino-amarille... more La Formacion Yacoraite esta constituida por rocas carbonaticas de color gris blanquecino-amarillento y en menor proporcion tambien por margas y areniscas color gris medio, limolitas color verde claro a rojo violado y arcilitas negras. Las intercalaciones peliticas negras constituyen la roca madre de hidrocarburos y los carbonatos conforman el reservorio. Se encuentra depositada en la Cuenca Cretacico/Terciaria del Noroeste argentino dentro del Subgrupo Balbuena que involucra tambien a la Formacion Lecho infrayacente depositadas durante un episodio de subsidencia termal. Previamente existio un periodo de rifting donde se deposito el Subgrupo Pirgua. Ambos Subgrupos conforman la base del Grupo Salta (Neocomiano-Eoceno). El Yacimiento Caimancito se ubica al este de la Serrania de Calilegua, provincia de Jujuy y su principal reservorio lo constituyen dolomias y calizas naturalmente fracturadas de la Formacion Yacoraite, con porosidad de 5,7 % y permeabilidad primaria de 0,1 mD a 8,1 mD ...
Summary The effort of eight decades of exploration and development in the Neuquen Basin (westcent... more Summary The effort of eight decades of exploration and development in the Neuquen Basin (westcentral Argentina) has identified a EUR of 9.7 BBOE, with a current daily production around 360 MBO and 2.6 BCFG. As result of the de-regularization and privatization process during the 90’s, the oil and gas reserves increased within the relatively mature productive tracts (Figure 1), where the known plays contain around 1.9 BBO and 17.5 TCFG of proven and probable reserves. Additional reserves are expected from testing new play concepts outside the areas under production, as well as from future activities in the under-explored fold belt and from the eastern margin of the basin (on the Pampean foreland). Focus of Study This work focuses on a quantitative comparison of the known productive districts by analyzing the geological elements and the processes involved in the charge, migration, accumulation, and preservation of hydrocarbons. The quantification of the generationaccumulation efficienc...
Journal of Geophysical Research: Solid Earth, 2016
This is a repository copy of Isolating active orogenic wedge deformation in the southern Subandes... more This is a repository copy of Isolating active orogenic wedge deformation in the southern Subandes of Bolivia.
Opening and Closure of the Neuquén Basin in the Southern Andes
Journal of South American Earth Sciences
Brazilian Journal of Geology
Geological studies in the northern sector of the Chaco foreland Basin, Bolivia, yielded new fossi... more Geological studies in the northern sector of the Chaco foreland Basin, Bolivia, yielded new fossils coming from late Oligocene-late Miocene of the Petaca Formation. Few fossil mammals were known from the Subandean Region of Bolivia. We report a partially complete mandible of a hegetotheriid Hegetotheriinae (Notoungulata, Typotheria) from Abapó (Río Grande River). The specimen (YPFB-LIT-PAL-005) is very close in size and dental morphology to the late Oligocene (Deseadan South American Land Mammal Age, SALMA)-Santacrucian (early Miocene) Prohegetotherium schiaffinoi (Kraglievich 1932) from Fray Bentos (Uruguay and Argentina), Salla (Bolivia), Divisadero Largo-Potrerillos and Quebrada Fiera (Argentina). However, mandibular characteristics, as the shape with a marked change in height along its length, increasing towards the back, a prominent masseteric crest, a deep mandibular groove, and a remarkable thickening of the ventral rim of the mandible, indicate differences between this specimen and Prohegetotherium schiaffinoi and the other Hegetotheriinae. The affinity of YPFB-LIT-PAL-005 with P. schiaffinoi suggests a late Oligocene to early Miocene for the upper bearing horizon of the Petaca Formation (in Abapó), an older age than previously assigned to the top of this unit (late Miocene), and confirms the taxon distribution between ~ 36 ° to ~ 17 ° south latitude.
VII Congreso de Exploración y Desarrollo de Hidrocarburos (Simposio de La Geofísica: Integradora del Conocimiento del Subsuelo)
VII Congreso de Exploración y Desarrollo de Hidrocarburos (Simposio de Sistemas Petroleros de las Cuencas Andinas)
PLOS ONE, 2024
Chitinozoans recovered from one section of the Middle Devonian Los Monos Formation in the TCB X-1... more Chitinozoans recovered from one section of the Middle Devonian Los Monos Formation in the TCB X-1001-Tacobo borehole, sub-Andean basin of Bolivia, have been analysed. Eleven from the eighteen processed cutting samples yielded specimens that allowed taxonomic study. Eleven genera and thirty-five chitinozoan species were identified from the Los Monos Formation with four of them recorded for the first time in Western Gondwana. Ancyrochitina biconstricta, Ancyrochitina parisi, Angochitina galarzae and Ramochitina boliviensis are among the most relevant taxa restricted to Western Gondwana that support the affinity with this paleocontinent. One new species, Lagenochitina tacobensis sp. nov. is described, and Ramochitina candelariaensis sp. nov. (n. n.) is formally erected. The chitinozoan assemblage reinforces the late Eifelian-middle Givetian age previously proposed by organic-walled phytoplankton and miospores for this section of the TCB X-1001-Tacobo borehole. A new local chitinozoan biozonation based on the chitinozoan assemblages is proposed and a revision of the current chitinozoan biozonation for Western Gondwana and Bolivia is recommended.
PloS one, Apr 9, 2024
Chitinozoans recovered from one section of the Middle Devonian Los Monos Formation in the TCB X-1... more Chitinozoans recovered from one section of the Middle Devonian Los Monos Formation in the TCB X-1001-Tacobo borehole, sub-Andean basin of Bolivia, have been analysed. Eleven from the eighteen processed cutting samples yielded specimens that allowed taxonomic study. Eleven genera and thirty-five chitinozoan species were identified from the Los Monos Formation with four of them recorded for the first time in Western Gondwana. Ancyrochitina biconstricta, Ancyrochitina parisi, Angochitina galarzae and Ramochitina boliviensis are among the most relevant taxa restricted to Western Gondwana that support the affinity with this paleocontinent. One new species, Lagenochitina tacobensis sp. nov. is described, and Ramochitina candelariaensis sp. nov. (n. n.) is formally erected. The chitinozoan assemblage reinforces the late Eifelian-middle Givetian age previously proposed by organic-walled phytoplankton and miospores for this section of the TCB X-1001-Tacobo borehole. A new local chitinozoan biozonation based on the chitinozoan assemblages is proposed and a revision of the current chitinozoan biozonation for Western Gondwana and Bolivia is recommended.
The objective of this work is to discuss the paleoenvironment and age of the Los Monos Formation,... more The objective of this work is to discuss the paleoenvironment and age of the Los Monos Formation, in outcrop and subsurface, along a regional transect (west-east) in the southern sector of the Tarija basin. The lithofacies and ichnofacies of the Alarache, Angosto del Pescado and Balapuca outcrops and core-intervals of the Aguas Blancas xp-13, Ramos x-12, Tartagal x-1 and Tonono x-1 boreholes were analyzed. The definition of lithofacies and ichnofacies allowed us to interpret a shallow to outer shelf paleoenvironment (from the offshore-transition, offshore and shelf). Towards the top of the Tonono Formation, the equivalent of the Los Monos Formation in the Chaco-Salteño was defined as a brackish-waters marginalmarine paleoenvironment. The mineralogy of the mentioned sections plus the Vespucio x-1 borehole was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), thus the majority elements in clay minerals were also determined from EDAX. Authigenic and detrital c...
The Neuquen basin of west-central Argentina is a triangular-shaped depocenter covering more than ... more The Neuquen basin of west-central Argentina is a triangular-shaped depocenter covering more than 160,000 km2. It accounted for about 44% of Argentinian oil production in 1992. The tectonic evolution spans about 220 m.y. of subsidence which preserves a Mesozoic-Cenoz oic basin fill at least 7,000 m thick. Initial rifting in the Triassic is characterized by basementinvolved normal extensional fault s which bound discrete half grabens separated by transfer faults. From the Aalenian onward, fault-controlled subsidence was replaced by regional subsidence and the rifts and their intervening highs were yoked together in a broad post-rift basin. The stratigraphic record is punctuated by several unconformities which reflect intermittent subsidence as well as multiple episodes of structural inversion. From the Callovian onward, the Neuquen basin was subjected to periodic inversion of earlier extensional structures which modified the shape of the basin and rejuvenated fringing sedimentary sour...
In the southern sub-Andean region of Bolivia, most of the structurally controlled hydrocarbon tra... more In the southern sub-Andean region of Bolivia, most of the structurally controlled hydrocarbon traps are related to the development of the Andean fold-and-thrust belt. The present study analyzed the structure and the hydrocarbon accumulations at the south sub-Andean “wedge-top.” The structural decoupling in the allochthonous section is characterized by two vertical overlapping structural levels, and the general geometry is defined as a trailing imbricate fan system. Backthrusts, lateral ramps, and tear faults are associated with the shallow structural level. They can act either as barriers or as secondary migration pathways for hydrocarbon accumulations. Related traps show three- and four-way dip closure, but only the latter were productive. The Curiche and Tajibo gas fields are two examples that produce from Cenozoic units in this structural domain. The deeper structural level is defined by thrust sheets with no forelimb development, generating three-way dip closure traps. The Tacob...
Revista de la Asociaci�n Geol�gica Argentina, 2016
AAPG Bulletin, 1995
Tectonic Evolution and Paleogeography of the Neuquén Basin, Argentina GD Vergani Perez Companc Ne... more Tectonic Evolution and Paleogeography of the Neuquén Basin, Argentina GD Vergani Perez Companc Neuquén, Argentina AJ Tankard Tankard Enterprises Calgary, Alberta, Canada HJ Belotti HJ Welsink Perez Companc Neuquén, Argentina Abstract The tectonic evolution of ...
Se presenta una descripcion e interpretacion de las estructuras de deformacion en las diferentes ... more Se presenta una descripcion e interpretacion de las estructuras de deformacion en las diferentes posiciones estructurales (flanco, charnela) del anticlinal Tin Tin, un pliegue con nucleo de basamento formado durante la contraccion cenozoica andina en el sector suroeste de la Cordillera Oriental del noroeste argentino. La gran mayoria de las estructuras son pliegues asociados a fallas inversas de bajo angulo con transporte occidental que en conjunto afectan a todas las unidades del Grupo Salta, y producen un engrosamiento de la cobertura sedimentaria. La cinematica de las estructuras coincide con la del anticlinal principal (vergencia y transporte occidental) y en general presentan su misma orientacion NNE-SSO. En menor medida se encuentran fallas de rumbo con alta inclinacion y orientacion oblicua a la del anticlinal. Las relaciones geometricas entre las estructuras en la cobertura sedimentaria indican una cronologia que sugiere una deformacion de piel fina relativamente previa al a...
Ameghiniana, 1995
... Su presencia con-firmaría con mayor fuerza aún la edad cretácica asig-nada al Horizonte Calcá... more ... Su presencia con-firmaría con mayor fuerza aún la edad cretácica asig-nada al Horizonte Calcáreo Dolomítico y las Margas Multicolores". Es muy posible que Reig haya opinado de esa manera por cuanto asoció los peces con formas cretácicas (o supuestamente cretácicas ...
UNIRED: PROYECTO PADRINAZGO PUBLICACIONES PERIODICAS ARGENTINAS. Título (A): Cuencas del extremo ... more UNIRED: PROYECTO PADRINAZGO PUBLICACIONES PERIODICAS ARGENTINAS. Título (A): Cuencas del extremo austral de la placa sudamericana: diferencias, conexiones y una historia en común, pp. 201-206. Autor Personal ...
Journal of South American Earth Sciences, 2010
The common elements and differences of the neighboring Austral (Magallanes), Malvinas and South M... more The common elements and differences of the neighboring Austral (Magallanes), Malvinas and South Malvinas (South Falkland) sedimentary basins are described and analyzed. The tectonic history of these basins involves Triassic to Jurassic crustal stretching, an ensuing Early ...
La Formacion Yacoraite esta constituida por rocas carbonaticas de color gris blanquecino-amarille... more La Formacion Yacoraite esta constituida por rocas carbonaticas de color gris blanquecino-amarillento y en menor proporcion tambien por margas y areniscas color gris medio, limolitas color verde claro a rojo violado y arcilitas negras. Las intercalaciones peliticas negras constituyen la roca madre de hidrocarburos y los carbonatos conforman el reservorio. Se encuentra depositada en la Cuenca Cretacico/Terciaria del Noroeste argentino dentro del Subgrupo Balbuena que involucra tambien a la Formacion Lecho infrayacente depositadas durante un episodio de subsidencia termal. Previamente existio un periodo de rifting donde se deposito el Subgrupo Pirgua. Ambos Subgrupos conforman la base del Grupo Salta (Neocomiano-Eoceno). El Yacimiento Caimancito se ubica al este de la Serrania de Calilegua, provincia de Jujuy y su principal reservorio lo constituyen dolomias y calizas naturalmente fracturadas de la Formacion Yacoraite, con porosidad de 5,7 % y permeabilidad primaria de 0,1 mD a 8,1 mD ...
Summary The effort of eight decades of exploration and development in the Neuquen Basin (westcent... more Summary The effort of eight decades of exploration and development in the Neuquen Basin (westcentral Argentina) has identified a EUR of 9.7 BBOE, with a current daily production around 360 MBO and 2.6 BCFG. As result of the de-regularization and privatization process during the 90’s, the oil and gas reserves increased within the relatively mature productive tracts (Figure 1), where the known plays contain around 1.9 BBO and 17.5 TCFG of proven and probable reserves. Additional reserves are expected from testing new play concepts outside the areas under production, as well as from future activities in the under-explored fold belt and from the eastern margin of the basin (on the Pampean foreland). Focus of Study This work focuses on a quantitative comparison of the known productive districts by analyzing the geological elements and the processes involved in the charge, migration, accumulation, and preservation of hydrocarbons. The quantification of the generationaccumulation efficienc...
Journal of Geophysical Research: Solid Earth, 2016
This is a repository copy of Isolating active orogenic wedge deformation in the southern Subandes... more This is a repository copy of Isolating active orogenic wedge deformation in the southern Subandes of Bolivia.
Opening and Closure of the Neuquén Basin in the Southern Andes
Journal of South American Earth Sciences
Brazilian Journal of Geology
Geological studies in the northern sector of the Chaco foreland Basin, Bolivia, yielded new fossi... more Geological studies in the northern sector of the Chaco foreland Basin, Bolivia, yielded new fossils coming from late Oligocene-late Miocene of the Petaca Formation. Few fossil mammals were known from the Subandean Region of Bolivia. We report a partially complete mandible of a hegetotheriid Hegetotheriinae (Notoungulata, Typotheria) from Abapó (Río Grande River). The specimen (YPFB-LIT-PAL-005) is very close in size and dental morphology to the late Oligocene (Deseadan South American Land Mammal Age, SALMA)-Santacrucian (early Miocene) Prohegetotherium schiaffinoi (Kraglievich 1932) from Fray Bentos (Uruguay and Argentina), Salla (Bolivia), Divisadero Largo-Potrerillos and Quebrada Fiera (Argentina). However, mandibular characteristics, as the shape with a marked change in height along its length, increasing towards the back, a prominent masseteric crest, a deep mandibular groove, and a remarkable thickening of the ventral rim of the mandible, indicate differences between this specimen and Prohegetotherium schiaffinoi and the other Hegetotheriinae. The affinity of YPFB-LIT-PAL-005 with P. schiaffinoi suggests a late Oligocene to early Miocene for the upper bearing horizon of the Petaca Formation (in Abapó), an older age than previously assigned to the top of this unit (late Miocene), and confirms the taxon distribution between ~ 36 ° to ~ 17 ° south latitude.
VII Congreso de Exploración y Desarrollo de Hidrocarburos (Simposio de La Geofísica: Integradora del Conocimiento del Subsuelo)
VII Congreso de Exploración y Desarrollo de Hidrocarburos (Simposio de Sistemas Petroleros de las Cuencas Andinas)