Carlos Conforti Ferreira Guedes

• Phd
• Professor (Assistant) at Federal University of Paraná

Natural cycles of irradiation during burial and bleaching due to solar exposure during transport increase the Optically Stimulated Luminescence (OSL) sensitivity of quartz sand grains. The relationship between the OSL sensitivity and sediment transport allows to discriminate quartz sand grains with different depositional histories. In this paper, w...

Ilha Comprida is a regressive barrier island located in southeastern Brazil that was formed essentially by Quaternary sandy sediments. Ilha Comprida sediments were analyzed to assess heavy mineral indices and grain size variables. The spatial variation of heavy minerals and grain size was interpreted in terms of the present barrier dynamics and the...

Holocene coastal barriers from southern Brazil present great geomorphological changes during their late stages of development. In this study, we investigate the Holocene evolution of the São Francisco do Sul (SFS) barrier through geomorphological, heavy minerals and grain size analyses constrained by Optically Stimulated Luminescence (OSL) dating....

Middle to Late Holocene barriers are conspicuous landforms in southeastern and southern Brazilian regions. The barriers in the coastal zones of northern Santa Catarina, Paraná and São Paulo states (27°19′–24°00′S) are formed mainly by beach ridge alignments and many barriers present foredune and blowout alignments in their seaward portion. The deve...

Barrier development during the Holocene is studied using the example of the Ilha Comprida, Southeastern Brazil. Aerial photos, facies analysis, and optically stimulated luminescence dating are used to define the barrier emergence and evolution. Optically stimulated luminescence ages and facies successions indicate that the Ilha Comprida probably be...

The increase in available data on proglacial fluvial systems through the 21st century has improved our knowledge on sediment transport processes, providing a better link between meltwater discharges and the depositional record. However, there are few studies on glacially related fluvial systems preserved in the deep-time geological record. Because...

Complete illustrations of Dawqara Fm lithic assemblage, Northern Jordan

The fluvial Dawqara Formation, upper Zarqa Valley, eastern side of Jordan Valley, is chronologically constrained between 2.52 and 1.98 Ma. Several artifact-bearing outcrops display a core and flake industry, with no handaxes nor planned flaking. Herein, we describe 40 artifacts from section 334 Lower, the earliest archeological site of the formatio...

There is a possibility that synthetic organic polymers might be preserved in the geological record when plastic is combined with denser material, such as rocks, pebbles, and sand. In this sense, novel plastic debris with a rock-like appearance has been reported worldwide in the marine environment. We reported the first plastic rock occurrences in B...

Introdução. A análise de proveniência sedimentar abrange a restauração dos elos existentes entre a rocha sedimentar e suas respectivas áreas fonte de sedimento. Objetivo e Metodologia. A unidade fundamental é a composição sedimentar detrítica. Entretanto, a composição detrítica não é reflexo unicamente da composição das rochas das áreas fontes, mas...

When no samples are available for direct comparisons during a criminal investigation, forensic scientists must resort to georeferenced soil databases in order to find the source of a single questioned evidence. To this end, several authors addressed many methods to infer the origin of soil samples, such as establishing search range intervals or def...

Continuous input of plastic litter in ocean and coastal environments achieved alarming levels that are exposing new settings in natural systems. While novel plastic debris pollution, with rock-like appearance, has been reported worldwide, fundamentally geological analyses are still lacking. We surveyed the first occurrence of multiple associated pl...

Souza and Perez Filho (2019) inferred two transgressive events in the Late Holocene record of lower Ribeira de Iguape River and Ilha Comprida barrier, Southeastern Brazil, based on luminescence ages and paleoenvironmental interpretation of four columnar sections. In the present paper, we discuss inconsistencies on the methods applied and sample des...

The interaction between coastal drift-dependent features, such as spit and inlet systems and the dynamics of estuaries, under the effect of tides, produces significant changes in coastal barriers depositional architecture. Extreme events associated with these autogenic factors insert elements of variability into the depositional architecture of the...

Humans took place as protagonists in the geological environment. New types of Anthropocene rocks yet reported are mainly composed of plastic originating from marine litter. The occurrence of geoplastic forms, i.e. materials containing plastic that can be geologically approached, was reported in Trindade Island, a Brazilian volcanic island located i...

We investigated the optically stimulated luminescence (OSL) and thermoluminescence (TL) characteristics of quartz from sediments and parent rocks across South America. OSL and TL sensitivities were compared with the characteristic dose of dose response curves. Additionally, we estimated electron trap parameters of quartz from sediments with contras...

The Cananéia-Iguape lagoon-estuarine system, where the Ilha Comprida barrier (IC) is located, is one of the most dynamic coastal areas on the southeastern Brazilian coast. IC island is a 63 km-long barrier and it is limited by the Icapara inlet to the north, and the Cananéia inlet to the south. This system has been affected by intense changes in it...

The global microplastic pollution achieved alarming levels posing challenges and affecting not only ecological or chemical systems, but also geological systems. In this scenario, recent studies have indicated the relationship between plastics and other marine litter items and geology, resulting in new terms such as plastiglomerates, pyroplastics, a...

Wave-dominated nearshore deposits are commonly regarded as laterally-continuous, homogeneous, sheet-like reservoirs that can be resolved at the parasequence scale. Many reservoirs, however, have an internal complexity that becomes clearer during production, indicating unexpected internal compartmentalization. Modern wave-dominated nearshore environ...

Changes in insolation driven by precession and obliquity are considered the major driver of tropical precipitation on orbital time scales, and responsible for vegetation and physical landscape changes during the Late Holocene over tropical South America. Here we investigate the environmental changes in the karst region of Chapada do Apodi-Northeast...

Heavy minerals are typically rare but important components of siliciclastic sediments and rocks. Their abundance, proportions, and variability carry valuable information on source rocks, climatic, environmental and transport conditions between source to sink, and diagenetic processes. They are important for practical purposes such as prospecting fo...

The chronology of Pleistocene strandplains remains a challenge to this day. The lack of reliable geochronology methods arises from the fact that ages from the Pleistocene sequences are beyond radiocarbon age limit method and, sometimes, near the saturation limits to luminescence dating on quartz, which may introduce uncertainties in the results. Al...

In tropical Southern Hemisphere South America, late Quaternary marine core and speleothem records provide different proxies and accurate chronologies correlating millennial-scale intervals of increased precipitation with southward shifts of the Intertropical Convergence Zone (ITCZ). However, the climatic effect of these intervals on coastal landfor...

Since many reservoirs do not allow direct observation due to their depth and/or difficulty of sampling, studies of analogs have been commonly used as a tool to understand the spatial distribution of reservoir properties. The Paraná Basin is 1.6 million km2 large and has two known petroleum systems. However, there are only 124 irregularly distribute...

This project aims to evaluate the predictive potential of a soil spatial database to geolocate unknown samples by building probabilistic models after geochemical, geophysical and sedimentological analysis of unknown samples.

This research aims to initiate a soil spatial database for forensic purposes, containing information about its mineral constituents (natural and anthropogenic) and biological, as well as geochemical analysis, in order to improve the investigative methods performed by the Brazilian Federal Police. In addition, it will seek to encourage the act of sa...

Sub-seismic sand-body characterization depends largely on understanding the heterogeneities observed in outcrops of equivalent depositional settings to subsurface reservoirs (reservoir analogs). Outcrop information, however, rarely covers the whole depositional system. Ground-penetrating radar (GPR), on the other hand, is a powerful tool for the hi...

The present work presented the first dated paleosealevel indicators and new paleogeographic reconstructions of the Island of Trindade. All evidence for Holocene sealevels point to the elevations higher than the present in the age interval between 5.06 ka and 0.55 ka. The altitude and ages of the reconstructions are in good agreement with hindcast m...

A Ilha da Trindade corresponde à pequena porção emersa de um grande edifício vulcânico, com cerca de 50 km de diâmetro e 5.500 m de altura, que se eleva do assoalho oceânico. Este edifício é o mais novo de uma série que compõem a cadeia Vitória-Trindade e foi formado nos últimos quatro milhões de anos 2,3. Para entender a evolução geomorfológica da...

The identification, characterization, and mapping of large areas of stabilized eolian features along the tropical northeastern Brazilian coast enabled recognition of the existence of one of the largest Quaternary dune fields (16,000 km ² ) in South America. This paleodune system is observed inland of the Lençóis Maranhenses transgressive dune field...

Resumo A região da foz do rio Itaguaré, localizada no Parque Estadual da Restinga de Bertioga-SP, apresenta uma miscelânea de processos sedimentares e formas de leito atuais gerados pela ação de marés, ondas e do próprio rio. Ocorrem também depósitos sedimentares quaternários expostos ao longo de falésia de dezenas de metros de extensão por até 4m...

We present here the first geochronometric analysis of a large succession of coastal ridges that developed south of Rio Grande do Sul inlet, aided by OSL dating of samples taken in this succession that amounts c. 306 coastal ridges. This succession allows defining epochs of enhanced coastal drift or fluvial transport to the river mouth. Additionally...

Ground-penetrating radar (GPR) is a reliable and useful method for the analysis of facies and depositional elements in the shallow subsurface, especially in sand-rich successions that usually form prolific hydrocarbon reservoirs in ancient successions. However, a comprehensive interpretation of the depositional character of radarfacies requires a c...

The Itaguare River mouth region, located in "Parque Estadual da Restinga de Bertioga-SP", is frequently used for didactic classes in sedimentary geology and related areas. It presents a miscellany of sedimentary processes and bed forms generated by the action of tides, waves and the river. Quaternary sedimentary deposits outcropping along a cliff w...

The development of optically stimulated luminescence (OSL) dating of sediments has led to considerable advance in the geochronology of the Quaternary. OSL dating is a well established technique to determine sediment burial ages from tens of years to few hundred thousand years. Recent studies have shown that Quaternary sediments of Brazil are domina...

During the past decades, there have been contrarian explanations for the formation and stabilization of coastal dunefields: while many authors believe the dunes formation would be enhanced by falling sea level, others argue that a rising or stable sea level context would be favorable. For Brazilian coastal dunefields, the second hypothesis seems to...

The eastern portion of the Maranhão coast is characterised by large active dune-fields located in a tropical setting. This article combines the analysis of dune-field morphologic patterns with the classical analysis of grain size and heavy minerals to study the sedimentary dynamics of the active aeolian system in this region. Based on the heavy min...

In the São Francisco do Sul (SFS) barrier in southern Brazil, the optically stimulated luminescence (OSL) and thermoluminescence (TL) sensitivities of coastal sands vary according to geomorphological units. Sands from older beach ridges (ages older than 2000 years ago) show higher OSL and TL sensitivities than younger units (ages younger than 2000...

Holocene coastal barriers from southern Brazil present great geomorphological changes during their late stages of development. The São Francisco do Sul (SFS) barrier stands out among the southern Brazilian barriers due to its well preserved morphology with a parabolic paleodune belt in the seaward portion. OSL-SAR dating and sensitivity, grain-size...

A morfodinâmica de sistemas eólicos costeiros é controlada pelo saldo sedimentar relativo, i.e., relação entre saldo absoluto (influxo-efluxo) e espaço de acumulação. Este espaço delimita-se pela extensão da área fonte e pelas dimensões de equilíbrio ou saturação: distância no rumo do vento (Deq) e altura (Heq) dentro das quais o saldo influxo-eflu...

The morphodynamics of coastal aeolian systems is controlled by the relative sedimentary balance, i.e., the ratio between absolute sediment balance (influx-efflux) and accumulation space. The accumulation space depends on source area extension as well as on the equilibrium (sand saturation) dimensions: the distance along wind direction (Deq) and the...

This study analyzes the optically stimulated luminescence (OSL) characteristics of quartz grains from fluvial, eolian and shallow marine sands of northeastern and southeastern Brazil, with especial focus on the applicability of the single-aliquot regenerative dose (SAR) dating protocol. All analyzed Brazilian sediments presented relatively high OSL...

The optically stimulated luminescence (OSL) sensitivity of quartz has a significant influence on luminescence dating procedures. Furthermore, identifying the natural controls of quartz OSL sensitivity is an important step towards new applications of OSL in geology such as provenance tracing. We evaluate the OSL sensitivity (total and the proportion...

Ilha Comprida, a Holocene barrier built by alignments of littoral ridges, underwent intense morphologic changes in the past 200 years, mainly in its NE extremity. These changes includes northward shifting of the Icapara inlet, local variation of the width of the island, the formation of a small transgressive dunefield, an increase in the width of t...

Ilha Comprida, a Holocene barrier built by alignments of littoral ridges, underwent intense morphologic changes in the past 200 years, mainly in its NE extremity. These changes includes northward shining of the Icapara inlet, local variation of the width of the island, the formation of a small transgressive dunefield, an increase in the width of th...

The use of seismic attributes has increased, especially when extracted from interpreted horizons. The various available attributes are not independent from each other but represent, in fact, different ways of presenting and studying fundamental information from seismic data (time, amplitude, frequency and attenuation). However, statistical analysis...

The facies and net-to-gross ratio (NTG) modeling methodology presented in this paper has been successfully applied on geological characterization of a giant field at Campos Basin, offshore Brazil. Such methodology aimed to preserve the seismic attribute original trend for NTG property in the facies model. In this way, more reliable horizontal param...

Monografia de Trabalho de Formatura--Instituto de Geociências da Universidade de São Paulo.