Episodic weathering in Southwestern Amazonia based on (U Th)/He dating of Fe and Mn lateritic duricrust

Albuquerque, Márcio Fernando dos Santos; Horbe, Adriana Maria Coimbra; Danišík, Martin

doi:10.1016/j.chemgeo.2020.119792

Cited by 12 publications

(7 citation statements)

References 53 publications

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“…1). Conventional and emerging directions include constraining paleotopography, landscape evolution, tectonic exhumation along normal faults, and erosional exhumation at the local and orogenic scale (refer to Reiners et al, 2018, for examples), as well as detrital studies to decipher sediment provenance (e.g., Stockli and Najman, 2020), Fe oxide investigations to address fault zone processes and weathering histories (e.g., Shuster et al, 2005;Cooperdock and Ault, 2020;dos Santos Albuquerque et al, 2020), extraterrestrial material studies to infer impact histories (e.g., Kelly et al, 2018;Tremblay and Cassata, 2020), dating of tephras and other volcanic products to quantify the ages of volcanic eruptions (e.g., Danišík et al, 2012Danišík et al, , 2021, and deep-time applications to decipher near-surface histories over hundreds of millions of years (e.g., McDannell and Flowers, 2020;Peak et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

(U-Th)/He chronology: Part 2. Considerations for evaluating, integrating, and interpreting conventional individual aliquot data

et al. 2022

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The (U-Th)/He dating technique is an essential tool in Earth science research with diverse thermochronologic, geochronologic, and detrital applications. It is now used in a wide range of tectonic, structural, petrological, sedimentary, geomorphic, volcanological, and planetary studies. While in some circumstances the interpretation of (U-Th)/He data is relatively straightforward, in other cases it is less so. In some geologic contexts, individual analyses of the same mineral from a single sample are expected to yield dates that differ well beyond their analytical uncertainty owing to variable He diffusion kinetics. Although much potential exists to exploit this phenomenon to decipher more detailed thermal history information, distinguishing interpretable intra-sample data variation caused by kinetic differences between crystals from uninterpretable overdispersion caused by other factors can be challenging. Nor is it always simple to determine under what circumstances it is appropriate to integrate multiple individual analyses using a summary statistic such as a mean sample date or to decide on the best approach for incorporating data into the interpretive process of thermal history modeling. Here we offer some suggestions for evaluating data, attempt to summarize the current state of thinking on the statistical characterization of data sets, and describe the practical choices (e.g., model structure, path complexity, data input, weighting of different geologic and chronologic information) that must be made when setting up thermal history models. We emphasize that there are no hard and fast rules in any of these realms, which continue to be an important focus of improvement and community discussion, and no single interpretational and modeling philosophy should be forced on data sets. The guiding principle behind all suggestions made here is for transparency in reporting the steps and assumptions associated with evaluating, integrating, and interpreting data, which will promote the continued development of (U-Th)/He chronology.

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Section: Introductionmentioning

confidence: 99%

(U-Th)/He chronology: Part 2. Considerations for evaluating, integrating, and interpreting conventional individual aliquot data

et al. 2022

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“…Indeed, previous dating studies (Mathian et al, 2019(Mathian et al, , 2020Allard et al, 2020) demonstrated that in uncapped regoliths, rejuvenation processes of secondary minerals triggered by the Quaternary precipitations results in the presence of minerals with a Quaternary age that can, with time, mask the signal of older minerals. Such a phenomenon is also observed within exposed duricrusts that often host rejuvenated iron oxides and oxyhydroxides (Allard et al, 2018;Wells et al, 2019;Albuquerque et al 2020). Accordingly, the detrital duricrust covering the in situ one in Syerton's regolith is expected to have favoured the preservation of a more robust long-term record of paleoweathering history that could be obliterated in uncapped regoliths from the inter-tropical zones.…”

Section: Introductionmentioning

confidence: 95%

“…The Miocene period seems to be characterized by a warm and wet climate at a global scale favoring the development of lateritic regoliths in South America (Alpers et Brimhall, 1988;Carmo et al, 2004;Balan et al, 2005;Carmo et al, 2006;Vaconcelos et al, 2015;Allard et al 2018;Mathian et al, 2020;dos Santos Albuquerque et al, 2020;Heller et al, 2022), Africa (Beauvais et al, 2008), India (Bonnet et al, 2016;Mathian et al, 2019) and even southern China (Li et al, 2007). However, despite extensive chronological studies in western and northern Australia, the extent of this hot and wet climate characterizing the Mid-Miocene Climatic Optimum over J o u r n a l P r e -p r o o f Australia is controversial (Travouillon et al, 2009;Metzger and Retallack, 2010;Herold et al, 2011;Greenwood et al, 2012;McLaren et al, 2014;Mao and Retallack, 2019).…”

Section: Paleoclimatic Constraints and Syerston Laterite Kaolinite Agesmentioning

confidence: 99%

Insights on the Cenozoic climatic history of Southeast Australia from kaolinite dating

Mathian

Chassé²,

Calas³

et al. 2022

Palaeogeography, Palaeoclimatology, Palaeoecology

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“…Despite occurring in distinct regions throughout the Amazon, lateritic profiles are coeval and correspond to paleoclimatic variations throughout the Cenozoic with lateritization ages mostly between 80 and 2 Ma (Allard et al, 2018; dos Santos Albuquerque et al, 2020; Théveniaut & Freyssinet, 2002). In the study area (Figures 1a and c), the laterites developed at the mouth of the Rio Trombetas, Rio Paru, and Rio Jari do not have constrained ages (e.g.…”

Section: Literature Reviewmentioning

confidence: 99%

“…In the Amazon region, the presence of knickpoints and other transient landscape features is commonly interpreted to reflect intraplate tectonism (Rossetti et al, 2015; Val et al, 2014), climate change (dos Santos Albuquerque et al, 2020; Irion et al, 2009; Pupim et al, 2019), and large‐scale continental tilting due to mantle and flexural warping of the surface (Bicudo et al, 2020; Sacek, 2014; Shephard et al, 2010). Though largely overlooked in the Amazon region, spatially variable bedrock lithology is known to cause long‐lasting river reorganizations in tectonically stable, post‐orogenic settings (e.g.…”

Section: Introductionmentioning

confidence: 99%

Ongoing landscape transience in the eastern Amazon Craton consistent with lithologic control of base level

Fadul

Oliveira

Val

2022

Earth Surf Processes Landf

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Geomorphic features such as drainage captures, knickpoints, paleochannels, and wind-gaps have long been observed in the Amazon region and typically thought to result from climate change and intraplate tectonics. The influence of rock type as a trigger of these landscape transients is largely overlooked. In the eastern Guiana Shield of the Amazon Craton, shield rivers flow over to the sedimentary rocks of the Amazon Basin across a sharp lithologic transition before their confluence with the Amazon River. This transition is marked by an expressive main escarpment (ME) formed over resistant sandstones of the basal units of the Amazon Sedimentary Basin. Here, systematic patterns of divide migration and river captures provide a natural laboratory to study the influence of rock type in landscape transience in a cratonic setting. Through quantitative geomorphologic analysis of the topography, drainage divides, and rivers, we investigate if this sharp lithologic transition contributed to the observed patterns of drainage rearrangement. The results revealed that rivers of larger drainage areas flowing across shorter lengths over the resistant rocks of the ME systematically capture neighbouring basins. We argue that, as tributaries draining the shield respond to downcutting and/or base-level fall of the Amazon River, bedrock incision and knickpoint propagation are differentially slowed down by the resistant rocks according to their incision capacity, generating a series of transients such as drainage capture and divide migration. The widespread and systematic geomorphic features suggest this mechanism could be an important autogenic control of drainage network rearrangement in the Amazon region and other postorogenic landscapes as well. The protracted exhumation of resistant rocks in cratons and intraplate settings may keep landscapes in perpetual disequilibrium depending on their lithological complexity and offer an exceptional natural laboratory to study landscape dynamics associated with rock type.

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Episodic weathering in Southwestern Amazonia based on (U Th)/He dating of Fe and Mn lateritic duricrust

Cited by 12 publications

References 53 publications

(U-Th)/He chronology: Part 2. Considerations for evaluating, integrating, and interpreting conventional individual aliquot data

(U-Th)/He chronology: Part 2. Considerations for evaluating, integrating, and interpreting conventional individual aliquot data

Insights on the Cenozoic climatic history of Southeast Australia from kaolinite dating

Ongoing landscape transience in the eastern Amazon Craton consistent with lithologic control of base level

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