First archaeointensity reference paleosecular variation curve for South America and its implications for geomagnetism and archaeology

AbstractWe report comprehensive rock-magnetic and archaeointensity investigations from 21 well-constrained pottery fragments from the Catamarca province of northwest Argentina. The absolute ages of the studied sites are ascertained by several high-quality radiometric ages and range between 1940 to 114014C yr BP. Magnetic mineralogy experiments indicates that the remanence is carried by thermally stable Ti-poor titanomagnetites. Forty-seven samples belonging to 11 out of 98 studied potsherds yielded reliable absolute intensity determinations judging from the quality parameters associated with the Thellier double-heating experiments. Moreover, we analyzed the available absolute geomagnetic intensities associated with the radiometric ages to construct the first intensity paleosecular variation curve (PSVC) for South America using thermoremanent magnetization carried by burned archaeological artifacts obtained in the present investigation and 79 other selected archaeointensities (out of 213 published in the literature). The dataset is used to build the PSVC reference curve by combined bootstrap and temporal P-spline methods. The variation curve shows significant differences with the global prediction model SHA.DIF.14k mainly based on the GEOMAGIA database. This intensity PSVC curve shows reasonably good agreement with paleosecular variation curves for Europe between 850 through 1150 BC and for Asia between 1000 and 1500 BC. This regional curve may be used as most reliable archaeomagnetic dating tool for the major part of South America (Peru, Brazil, Argentina, Chile, and Bolivia) for the last two millennia.

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First archaeointensity reference paleosecular variation curve for South America and its implications for geomagnetism and archaeology – Corrigendum

Quaternary Research ◽

10.1017/qua.2020.17 ◽

2020 ◽

Vol 98 ◽

pp. 103-103

Author(s):

Avto Goguitchaichvili ◽

Catriel Greco ◽

Rafael Garcia Ruiz ◽

Lucas Pereyra Domingorena ◽

Ruben Cejudo ◽

...

Keyword(s):

South America ◽

Paleosecular Variation ◽

Variation Curve

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Quality Assessment and Mathematical Modeling of Hot-Air Convective Drying of Persimmon (Diospyros kaki L.) Fruit

International Journal of Food Engineering ◽

10.1515/ijfe-2016-0333 ◽

2017 ◽

Vol 13 (7) ◽

Cited By ~ 3

Author(s):

Claudia Giovagnoli-Vicuña ◽

Nelson O. Moraga ◽

Vilbett Briones-Labarca ◽

Pablo Pacheco-Pérez

Keyword(s):

Quality Parameters ◽

Time Function ◽

Convective Drying ◽

Diospyros Kaki ◽

Drying Process ◽

Temperature Function ◽

Persimmon Fruit ◽

Hot Air ◽

Volume Method ◽

Good Agreement

Abstract The influence of drying on the color, porosity, shrinkage and moisture of persimmon fruit during convective drying was determined by computer vision. The experiments were performed with persimmon fruit that were cut into slab 20 × 20 mm, which were arranged into a bigger slab, 60 × 60 mm. Drying process was carried out at 60 °C. Noticeable changes in quality parameters (color, porosity and shrinkage) could be observed during the drying process, where the central region of the sample evidenced less changes. Persimmon’s physical properties were experimentally obtained as the temperature function and heat and mass convective coefficients were adjusted as a time function. A numerical simulation using the Finite Volume Method allowed to describe the evolution of temperature and moisture content distributions during drying. The numerical and experimental results of temperature and moisture during persimmon drying were found to be in a good agreement.

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Climate Change in Southern South America During the Last Two Millennia

Past Climate Variability in South America and Surrounding Regions - Developments in Paleoenvironmental Research ◽

10.1007/978-90-481-2672-9_15 ◽

2009 ◽

pp. 353-393 ◽

Cited By ~ 29

Author(s):

Christopher M. Moy ◽

Patricio I. Moreno ◽

Robert B. Dunbar ◽

Michael R. Kaplan ◽

Jean-Pierre Francois ◽

...

Keyword(s):

Climate Change ◽

South America ◽

Southern South America ◽

The Last Two Millennia

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Pb pollution from leaded gasoline in South America in the context of a 2000-year metallurgical history

Science Advances ◽

10.1126/sciadv.1400196 ◽

2015 ◽

Vol 1 (2) ◽

pp. e1400196 ◽

Cited By ~ 27

Author(s):

Anja Eichler ◽

Gabriela Gramlich ◽

Thomas Kellerhals ◽

Leonhard Tobler ◽

Margit Schwikowski

Keyword(s):

South America ◽

Road Traffic ◽

Ice Core ◽

Enrichment Factors ◽

Leaded Gasoline ◽

Pb Pollution ◽

Pollution Levels ◽

Andean Altiplano ◽

The 1960S ◽

The Last Two Millennia

Exploitation of the extensive polymetallic deposits of the Andean Altiplano in South America since precolonial times has caused substantial emissions of neurotoxic lead (Pb) into the atmosphere; however, its historical significance compared to recent Pb pollution from leaded gasoline is not yet resolved. We present a comprehensive Pb emission history for the last two millennia for South America, based on a continuous, high-resolution, ice core record from Illimani glacier. Illimani is the highest mountain of the eastern Bolivian Andes and is located at the northeastern margin of the Andean Altiplano. The ice core Pb deposition history revealed enhanced Pb enrichment factors (EFs) due to metallurgical processing for silver production during periods of the Tiwanaku/Wari culture (AD 450–950), the Inca empires (AD 1450–1532), colonial times (AD 1532–1900), and tin production at the beginning of the 20th century. After the 1960s, Pb EFs increased by a factor of 3 compared to the emission level from metal production, which we attribute to gasoline-related Pb emissions. Our results show that anthropogenic Pb pollution levels from road traffic in South America exceed those of any historical metallurgy in the last two millennia, even in regions with exceptional high local metallurgical activity.

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Organic versus integrated apple growing: II. differences in fruit quality parameters

International Journal of Horticultural Science ◽

10.31421/ijhs/15/4/842 ◽

2009 ◽

Vol 15 (4) ◽

Author(s):

P. T. Nagy ◽

Z. Szabó ◽

J. Nyéki ◽

I. Gonda ◽

I. J. Holb

Keyword(s):

Production System ◽

Dry Matter ◽

Quality Parameters ◽

Measured Data ◽

Matter Content ◽

Research Station ◽

Dry Matter Content ◽

Nutrients Uptake ◽

Good Agreement

The aim our study was to establish whether significant differences in nutrients uptake and quality of fruit existbetween organic and integrated grown apples. The study was performed at the orchard Fruit Research Station, University of Debrecen, at Debrecen-Pallag during 2002–2004. Diameter (mm), weight (g), firmness (N/cm2), dry matter (%) and Vitamin C in fruit were determined. Diameter data showed that the size of apples strongly depended on cultivars and organic apples were larger than integrated ones. Moreover, the effect of year and species strongly affected the apple diameter, size and weight. Measured data of firmness were good agreement in data of diameter and weight. Larger fruits have lower values of firmness due to the structure of fruit flesh. Dry matter content of apples varied between 14.66 and 18.07 in integrated, and 12.87 and 17.29 in organic apples according to cultivars. Values were affected by years and cultivars. From results it was evident that the dry matter content of apples affected by production system. It was lower in organic samples than integrated ones.Vitamin C content of apples was stronger affected by species and years than production system.

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Full‐vector paleosecular variation curve for the Azores: enabling reliable paleomagnetic dating for the past 2 kyr

Journal of Geophysical Research Solid Earth ◽

10.1029/2020jb019745 ◽

2020 ◽

Author(s):

Annemarieke Béguin ◽

Adriano Pimentel ◽

Lennart V. de Groot

Keyword(s):

Paleosecular Variation ◽

The Past ◽

Variation Curve ◽

Paleomagnetic Dating ◽

Full Vector

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Area-Based Approach in Power Quality Assessment

International Journal of Power Management Electronics ◽

10.1155/2008/147359 ◽

2008 ◽

Vol 2008 ◽

pp. 1-6 ◽

Cited By ~ 8

Author(s):

Surajit Chattopadhyay ◽

Samarjit Sengupta ◽

Madhuchhanda Mitra

Keyword(s):

Power Quality ◽

Quality Parameters ◽

Computational Effort ◽

Phase System ◽

Transformation Technique ◽

Three Phase ◽

Harmonic Voltage ◽

Park Transformation ◽

Harmonic Components ◽

Good Agreement

This paper presents an approach for assessment of power quality parameters using analysis of fundamental and harmonic voltage and current waveforms. Park transformation technique has been utilized for the analysis in three-phase system, which has reduced the computational effort to a great extent. Contributions of fundamental and harmonic components in power system voltage and current signals have been assessed separately. An algorithm has been developed to calculate the power quality parameters from online signals. This algorithm has been simulated for a radial system, and the results have been compared with that obtained from a standard FFT-based system. The results are seen to be in good agreement with that of the standard system.

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Calibrating the temporal and spatial dynamics of the Ediacaran - Cambrian radiation of animals

10.31223/x5ck7b ◽

2021 ◽

Author(s):

Fred Bowyer ◽

Andrey Zhuravlev ◽

Rachel Wood ◽

Graham Shields ◽

Ying Zhou ◽

...

Keyword(s):

Evolutionary Dynamics ◽

Spatial Dynamics ◽

Temporal Position ◽

Reference Curve ◽

Carbonate Carbon ◽

Global Age ◽

Cambrian Radiation ◽

Temporal And Spatial ◽

Radiometric Ages

The Ediacaran-Cambrian transition, which incorporates the radiation of animals, lacks a robust global temporal and spatial framework, resulting in major uncertainty in the evolutionary dynamics of this critical radiation and its relationship to changes in palaeoenvironmental geochemistry. We first present a new δ13Ccarb composite reference curve for the Ediacaran Nama Group of southern Namibia, and we then outline four new possible global age models (A to D) for the interval 551-517 million years ago (Ma). These models comprise composite carbonate-carbon isotope (δ13Ccarb) curves, which are anchored to radiometric ages and consistent with strontium isotope chemostratigraphy, and are used to calibrate metazoan distribution in space and time. These models differ most prominently in the temporal position of the basal Cambrian negative δ13Ccarb excursion (BACE). Regions that host the most complete records show that the BACE nadir always predates the Ediacaran-Cambrian boundary as defined by the first appearance datum (FAD) of the ichnospecies Treptichnus pedum. Whilst treptichnid traces are present in the late Ediacaran fossil record, the FAD of the ichnospecies T. pedum appears to post-date the LAD of in situ Cloudina and Namacalathus in all environments with high-resolution δ13Ccarb data. Two age models (A and B) place the BACE within the Ediacaran, and yield an age of ~538.8 Ma for the Ediacaran-Cambrian boundary; however models C and D appear to be the most parsimonious and may support a recalibration of the boundary age by up to 3 Myr younger. All age models reveal a previously underappreciated degree of variability in the terminal Ediacaran, incorporating notable positive and negative excursions that precede the BACE. Nothwithstanding remaining uncertainties in chemostratigraphic correlation, all models support a pre-BACE first appearance of Cambrian-type shelly fossils in Siberia and possibly South China, and show that the Ediacaran-Cambrian transition was a protracted interval represented by a series of successive radiations.

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