Cross-strata palaeocurrent analysis using virtual outcrops

Author(s)

Freitas, Bernardo T. ^[1] ; Silva, Leonardo H. G. ^[1] ; Almeida, Renato P. ^[2] ; Galeazzi, Cristiano P. ^[2] ; Figueiredo, Heitor G. ^[2] ; Tamura, Larissa N. ^[2] ; Janikian, Liliane ^[3] ; Figueiredo, Felipe T. ^[4] ; Assine, Mario L. ^[5]

Affiliation

^[1] Univ Estadual Campinas, Sch Technol, Geol Lab, Rua Paschoal Marmo 1888, BR-13484332 Limeira, SP - Brazil

^[2] Univ Sao Paulo, Inst Geosci, Rua Lago 562, Cidade Univ, BR-05508080 Sao Paulo, SP - Brazil

^[3] Sao Paulo Fed Univ, Inst Marine Sci, Rua Carvalho Mendonca 144, BR-11070100 Santos, SP - Brazil

^[4] Univ Fed Sergipe, Programa Posgrad Geociencias & Anal Bacias, Dept Geol DGEOL, Marechal Rondon Ave, Geol Bldg, Multiuser Complex, BR-49100000 Sao Cristavelo, SE - Brazil

^[5] Univ Estadual Paulista UNESP, Inst Geociencias & Ciencias Exatas, Dept Geol Aplicada, Ave 24-A, Bela Vista 178, BR-13506900 Rio Claro, SP - Brazil

• Document type: Journal article
• Source: SEDIMENTOLOGY; v. 68, n. 6, p. 2397-2421, OCT 2021.
• Web of Science Citations: 1

Abstract

Although virtual outcrops or digital outcrop model applications in geological studies are becoming increasingly common, virtually no attention has been given to acquisition of palaeocurrent data from cross-strata. Palaeocurrent indicators are abundant in the sedimentary record, mainly as cross-strata, and present compelling implications for basin analysis, plate tectonics and palaeoenvironmental reconstructions, as well as for sediment transport systems. Palaeocurrents from cross-strata also comprise a quantifiable parameter in sedimentary successions that can be used in quantitative modelling of depositional architecture with implications for reservoir characterization through outcrop analogue studies. A common obstacle in obtaining large cross-strata orientation datasets is the limited access to steep and high outcrop faces, as well as financial and time restrictions on field work. To overcome these issues, the simplest workflow for drone-based acquisition, photogrammetric processing and analysis of virtual outcrops aiming at the attainment of palaeocurrent data from cross-strata is appraised here. The results show that orientations of cross-beds measured on virtual outcrops, with and without ground control points, and using two different levels of resolution downsampling, are comparable to field measurements using analogue and electronic devices. Time and financial resources can thus be saved by using the straightforward method presented here to supplement palaeocurrent mapping across wide areas and distinct stratigraphic intervals. (AU)

• FAPESP's process: 16/03091-5 - CHARACTERIZATION OF HETEROGENEITIES AND MODELING OF RESERVOIR ANALOGUES IN FLUVIAL AND EOLIAN DEPOSITS
• Grantee: Liliane Janikian Paes de Almeida
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/00519-9 - Centralities of night-time leisure in the city of São Carlos-SP and the interface relations
• Grantee: Tiago Ferreira Lopes Machado
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 16/19736-5 - Quantitative approaches for big river deposits: integrated field geology and 3D photogrammetric models
• Grantee: Bernardo Tavares Freitas
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/06874-3 - Fluvial dynamics and sedimentary deposits in the Amazon channel: providing tools to decipher the paleogeographical evolution of Amazonia and deposits of large anabranching rivers in the rock record
• Grantee: Cristiano Padalino Galeazzi
• Support Opportunities: Scholarships in Brazil - Doctorate