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Exploring South America’s Active Margin (Colombia, Ecuador, Peru and Chile) PRESENTATION ABSTRACTS DAY 1 – OCTOBER 22, 2020 SESSION I: STRUCTURAL GEOLOGY & TECTONICS 1.I Keynote Presentation: Building an Andes Plate Tectonic Reconstruction Back to the Late Cretaceous ~80 Ma Using Unfolded Slabs from Seismic Tomography: Implications for Flat Slab Tectonics Yi-Wei Chen (presenter), Jonny Wu, John Suppe, University of Houston ........................................ 4 1.II Tectonic-Structural Analysis of the Chilean Forearc (Offshore) Between 28.5° and 37.5°: Effects of Subduction in Submarine Morph-Structures Pablo Sebastian González Godoy (presenter) Cristian Rodrigo Ramirez. Universidad Andres Bello, Sede Viña del Mar, Chile .................................................................................................................. 4 1.III Cenozoic Structural Style and Tectonic Evolution of East Pisco Basin, Offshore Peru: Implications for an Active Petroleum System Daniel Peña1 (presenter), Diego Timoteo2, Pedro Alarcon3; 1Repsol, 2Hound Exploration, 3Independent .................................................................................................................................... 7 1.IV Structural Analysis of the Talara Basin - E&P Implications Carlos Llerena (presenter), Diego Escobedo, Christopher Villafuerte, Savia Peru S.A. .................... 7 1.V Forearc Basin Development Along the Southernmost Boundary of the Northern Andes Carlos Aizprua1,2, (presenter), Cesar Witt2, Jean-Yves Reynaud2, Diego Barba3; 1Norwegian University of Science and Technology, 2University of Lille, 3PetroAmazonas .................................. 8 1.VI Crustal Structure of The Southernmost Northern Andes: A Trapped Oceanic Sliver Cesar Witt1, (presenter); Carlos Aizprua1,2, Marco Brøner3, Diego Barba4; 1University of Lille, 2Norwegian University of Science and Technology, 3Geological Survey of Norway, 4PetroAmazonas ............................................................................................................................... 8 SESSION II: GEOPHYSICAL METHODS & INTERPRETATION 2.I Data Reprocessing, Enhancement and Integration to Unlock Hydrocarbon Potential of the Peruvian Offshore. Examples from the Underexplored Salaverry and Trujillo Basins Eloi Carola (presenter), David Spofforth, Shona Culwick, Emmanuel Nformi, CGG GeoSpec ......... 9 2.II Hydrocarbon Prospectivity Implications of BSR-derived Geothermal Gradient Offshore Peru Karyna Rodriguez (presenter), Neil Hodgson, Searcher ................................................................... 9 2.III Developing an Interactive RockAVO Modelling Atlas for Improved Geological Understanding of Offshore Peru Roberto Ruiz (presenter), William Powell, Adriana Sola, Cyrille Reiser, PGS ................................. 10 2.IV 2D/3D Seismic Activity Along Offshore Peru and its Contribution to Increasing the Basins’ Prospectivity Edgar Borda1 (presenter), Carlos Bianchi2; 1Energy Resources Consulting, 2SK Innovation ........... 12 1 2.V Direct Hydrocarbon Indicators Associated with Oligocene-Recent Folds of the Sandino Forearc Basin, Offshore Pacific Margin of Nicaragua Lila Bishop (presenter), Paul Mann, The University of Houston .................................................... 12 DAY 2 – OCTOBER 23, 2020 SESSION III: REGIONAL GEOLOGY AND BASIN ANALYSIS 3.I Keynote Presentation: Mantle Impressions of Latin American Subduction History Douwe G. van der Meer, CNOOC International ............................................................................. 13 3.II The Overlooked Mollendo Basin in Offshore Southern Peru: Is There a Working Petroleum System? Alejandro Quispe1 (presenter), Diego Timoteo2, Fritz Palacios2, Luis Pairazaman2; 1Perupetro S.A., 2Hound Exploration S.A.C. .............................................................................................................. 14 3.III Petroleum Systems Evidence and Exploration Opportunities in the Peruvian Offshore Frontier Areas (Salaverry and Pisco Basins) Kiko Valencia, Independent Consulting Geologist ......................................................................... 14 3.IV Hunting for the First Play Opener in Salaverry Basin, Offshore Central Peru Diego Timoteo1 (presenter), Fritz Palacios1, Alejandro Quispe2; 1Hound Exploration, S.A.C., 2Perupetro S.A. ............................................................................................................................... 15 3.V Tumaco Basin: Exploratory Insights from Basin Modeling and Sequence Stratigraphy Roberto Aguilera, RA Geologia E.U. ............................................................................................... 15 3.VI Chronostratigraphic Control and Evolution of the Southern East Pisco Basin (Peruvian Continental Margin from the Late Miocene to the Present Diana Ochoa1, Thomas DeVries2, Kelly Quispe1, Rodolfo Salas-Gismondi1,3, Matthieu Carré1,4; 1Universidad Peruana Cayetano Heredia, 2University of Washington, 3Museo de Historia Natural- Universidad Nacional Mayor de San Marcos, 4CNRS-IRD ............................................................... 16 SESSION IV: STRATIGRAPHY & SEDIMENTOLOGY 4.I Stratigraphy and Tectonics Along Coastal Southernmost Peru (15.6°S–18.3°S) Thierry P.A. Sempere, Independent Consulting Geologist ............................................................. 17 4.II Effects of Local Basin Analysis Evolution on Anatomy of Sedimentological Morphology and Dynamics for the Delivery of Mud to Deep-Water Environments Characteristics- Pleistocene Gulf of Guayaquil (Ecuador) Afsoon Kazerouni, Bemidji State University, Center for Sustainability Studies ............................. 21 4.III Miocene Turbiditic Successions of the San Juan Sub-basin, Potential Reservoir and Seal Rocks in the Colombian Pacific Active Margin Carlos Rey1, Juan Patiño2, Jaime Reyes-Abril2 (presenter), Freddy Corredor3; 1ANH Colombia, 2Servigecol, 3GeoStrAp ................................................................................................................... 22 4.IV Zircon Geochronology and Morphology to Decode the Evolution of Arequipa-Tarapacá Basin During the Middle Jurassic To Lower Cretaceous Angel Carlos Salas Colca, Universidad Nacional Daniel Alcides Carrión......................................... 22 4.VI The Identification and Implications of Large-Scale Clinoforms in the Austral-Magallanes Basin Outcrop Belt, Southern Chile Stephen Hubbard (presenter), Ben Daniels, Tom Peploe, University of Calgary; Brian Romans, Virginia Tech; Lisa Stright, Colorado State; Erin Pemberton, ConocoPhillips ................................ 23 2 SPECIAL PRESENTATIONS SP.I Exploration Opportunities in Northwest and Offshore Peru Eris Gabriel, Exploration Manager, PeruPetro ............................................................................... 23 SP.II Acquiring Information for Understanding Colombia’s Pacific Basins Carlos Rodríguez Taborda, Technical Vice President, ANH Colombia ............................................ 23 BIOGRAPHICAL SKETCHES SESSION I: STRUCTURAL GEOLOGY & TECTONICS .......................................................................... 24 SESSION II: GEOPHYSICAL METHODS & INTERPRETATION ............................................................ 25 SESSION III: REGIONAL GEOLOGY & BASIN ANALYSIS .................................................................... 26 SESSION IV: STRATIGRAPHY & SEDIMENTOLOGY .......................................................................... 28 CLOSING PANEL DISCUSSION ......................................................................................................... 29 3 PRESENTATION ABSTRACTS DAY 1 – OCTOBER 22, 2020 SESSION I: STRUCTURAL GEOLOGY & TECTONICS 1.I Building an Andes Plate Tectonic Reconstruction Back to the Late Cretaceous ~80 Ma Using Unfolded Slabs from Seismic Tomography: Implications for Flat Slab Tectonics Yi-Wei Chen (presenter), Jonny Wu, John Suppe, University of Houston The Andean margin has long been regarded as a classic example of long-lived, continuous oceanic lithosphere subduction beneath a continental margin. The current continuous subduction phase has apparently endured since the early Jurassic, or early Cenozoic, but uncertainty exists due to incomplete or missing geological records. Within a presumed context of continuous subduction, many studies have attributed episodic and localized changes in Andean deformation, magmatism and topography to repeated cycles of slab flattening and steepening or slab break-off (i.e. flat slabs). Here we present a slab-based, quantitative plate tectonic reconstruction that shows Andean subduction was not always continuous since the Mesozoic and has included episodic phases of strike-slip/transtension or divergence. Our results imply that plate tectonic-scale reorganizations and slab-mantle interactions – factors other than slab dip (i.e. flat slabs) – may have also played a crucial role in controlling the evolution of Andean geology. In this study we mapped and unfolded (i.e. structurally restored) the Nazca slabs from global seismic tomography to produce a quantitative, slab-constrained plate reconstruction of the Andes back to the late Cretaceous ~80 Ma. Our reconstruction implies a subduction resumption at late Cretaceous following a 100 to 80 Ma regional plate tectonic reorganization. We suggest our predicted plate reorganization event corresponds geologically to the Andean margin-wide compressional event at mid-late Cretaceous. Our plate model
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  • Portada Rgch 34-2.Jpg

    Portada Rgch 34-2.Jpg

    Crust-mantle interactions and generation of silicic melts: insights from the Sarmiento Complex, southern Patagonian Andes Mauricio Calderón Departamento de Geología, Universidad de Chile, Francisco Hervé Casilla 13518, Correo 21,Santiago, Chile [email protected] [email protected] Umberto Cordani Centro de Pesquisas Geocronológicas, Universidade de São Paulo, Rua do Lago 562, Cidade Universitaria, São Paulo, CEP 05508-900, Brazil [email protected] Hans-Joachim Massonne Institut für Mineralogie und Kristallchemie, Universität Stuttgart, Azenbergstrasse 18, D-70174, Stuttgart, Germany [email protected] ABSTRACT A Late Jurassic seafloor remnant of the Rocas Verdes basin in southern Chile, the Sarmiento Complex (ca. 52°S), bears lithological layers with bimodal meta-igneous rocks appropriate for a comprehensive investigation of magma genesis in part of a lateral lithological transition from continental rifting to initial seafloor spreading. Metamorphosed mafic ε rocks collected from different layers in the ophiolite pseudostratigraphy and a plagiogranite have positive Nd150 values ε (+ 1 and +2). Granophyres, which are crosscut by ophiolitic mafic dikes, have negative Nd150 values (-5). Dacitic dikes ε within thick successions of pillow basalt have the least negative Nd150 values (-3 and -4). Although mafic and felsic igneous rocks show contrasting isotopic signatures, thermochemical modeling (EC-AFC) suggests they can share a common origin. Models consider an arbitrary composition of the crustal assimilant (mostly metapelite with an average ε Nd150 value of -7) and evaluate the feasibility for generation of silicic melts through the interaction of mafic magmas and metasedimentary rocks. A quantitative evaluation of basaltic magma contaminated by crustal wall rocks requires a Ma*/ Mc (mass of anatectic melt/ mass of cumulates) ratio of 0.04.