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

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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`Flowonthego' - flow tracking technology on your smartphone

10.5194/egusphere-egu21-5902 ◽

2021 ◽

Author(s):

Jonathan Higham ◽

Andrew Plater

Keyword(s):

Vector Fields ◽

Velocity Fields ◽

Flow Equations ◽

Video Footage ◽

The Past ◽

Naturally Occurring ◽

New Frontier ◽

The World ◽

Tracking Technology ◽

Full Vector

<p>Over the past few years, smartphone devices have become so powerful that in your pocket, not only do you have a device which can communicate with people across the world, the sheer power of these devices has now also brought a new frontier in scientific measurements. In this presentation, we present our smartphone app 'flowonthego', a technology which allows users to determine flow velocities, in almost real-time, from simple video footage. The instantaneous velocity fields are calculated by solving the Lucas-Kanade solutions to the optical flow equations and tracking naturally occurring features. The app also harnesses the potential of augmented reality, making calibration reference and the need tape measures a thing of the past. Furthermore, the app also packs an arsenal of post-processing tools in which users can understand basic statistics. From preliminary our studies we have found 'flowonthego' is able to match the statistics of commonly used ADCP's while also providing instantaneous full vector fields allowing users to better understand dynamical processing.&#160;</p><p><img src="https://contentmanager.copernicus.org/fileStorageProxy.php?f=gnp.9d2d602fcdff52519640161/sdaolpUECMynit/12UGE&app=m&a=0&c=2ba347a62b8a1a41850ed383c5014169&ct=x&pn=gnp.elif&d=1" alt=""></p>

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