TY - JOUR
T1 - Optimizing multiple non-invasive techniques (PXRF, pMS, IA) to characterize coarse-grained igneous rocks used as building stones
AU - Triantafyllou, A.
AU - Mattielli, Nadine
AU - Clerbois, S.
AU - Da Silva, Anne-Carine
AU - Kaskes, P.
AU - Claeys, Ph
AU - Devleeschouwer, Xavier
AU - Brkojewitsch, G.
N1 - Funding Information:
The first author (A.T) was an FRS-FNRS post-doctoral research fellow for the PROBARC project (Grant CR n° 1. B. 414.20 F ) during the conception and writing of this manuscript. NM and AT were supported by the F.R.S.-FNRS research credit CDR/OL J.0150.20 . AC. Da Silva thanks Liege university for the support “Equipement 2018” for its support on the project « XRF Portable - geochemistry as a climatic proxy in paleo-records.» P. Kaskes thanks Research Foundation Flanders (FWO) for the awarded Ph.D. Fellowship (projects 11E6619N, 11E6621N). Ph. Claeys thanks the Research Foundation Flanders (Hercules) for purchasing the PXRF. This research is authorized and subsidized by the Regional Service of Archaeology (SRA) directed by Laurent Sévègnes of the Regional Direction of Cultural Affairs of Corsica (DRAC), directed by Franck Leandri within the annual archeological program. This work is part of the Collective Research Program on “Les Bouches de Bonifacio à l'Epoque romaine: approches archéologique et géoarchéologique". This project brings together about twenty researchers from five institutions (Centre Camille Jullian-CNRS, CEREGE-CNRS, CReA Patrimoine/Université libre de Bruxelles, DRASSM, INRAP). The program is facilitated by the logistical support of the Heritage Department of the Bonifacio Town Hall headed by Mrs. Hélène Portafax and has received financial assistance from ARPAMED fund (Archaeology and Heritage in the Mediterranean). The authors thank A. McAlister and two anonymous reviewers for their constructive comments on this manuscript and R. Torrence for the editorial handling.
Funding Information:
The first author (A.T) was an FRS-FNRS post-doctoral research fellow for the PROBARC project (Grant CR n?1. B. 414.20 F) during the conception and writing of this manuscript. NM and AT were supported by the F.R.S.-FNRS research credit CDR/OL J.0150.20. AC. Da Silva thanks Liege university for the support ?Equipement 2018? for its support on the project ? XRF Portable - geochemistry as a climatic proxy in paleo-records.? P. Kaskes thanks Research Foundation Flanders (FWO) for the awarded Ph.D. Fellowship (projects 11E6619N, 11E6621N). Ph. Claeys thanks the Research Foundation Flanders (Hercules) for purchasing the PXRF. This research is authorized and subsidized by the Regional Service of Archaeology (SRA) directed by Laurent S?v?gnes of the Regional Direction of Cultural Affairs of Corsica (DRAC), directed by Franck Leandri within the annual archeological program. This work is part of the Collective Research Program on ?Les Bouches de Bonifacio ? l'Epoque romaine: approches arch?ologique et g?oarch?ologique". This project brings together about twenty researchers from five institutions (Centre Camille Jullian-CNRS, CEREGE-CNRS, CReA Patrimoine/Universit? libre de Bruxelles, DRASSM, INRAP). The program is facilitated by the logistical support of the Heritage Department of the Bonifacio Town Hall headed by Mrs. H?l?ne Portafax and has received financial assistance from ARPAMED fund (Archaeology and Heritage in the Mediterranean). The authors thank A. McAlister and two anonymous reviewers for their constructive comments on this manuscript and R. Torrence for the editorial handling.
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/5
Y1 - 2021/5
N2 - We present a workflow to conduct a full characterization of medium to coarse-grained igneous rocks, using portable, non-invasive, and reproducible approaches. This includes: (i) Image Analysis (IA) to quantify mineral phase proportions, grain size distribution using the Weka trainable machine learning algorithm. (ii) Portable X-ray fluorescence spectrometer (PXRF, Bruker Tracer IV) to quantify the whole-rock's chemical composition. For this purpose, a specific calibration method dedicated to igneous rocks using the open-source CloudCal app was developed. It was then validated for several key elements (Si, Al, K, Ti, Ca, Fe, Mn, Sr, Ga, Ba, Rb, Zn, Nb, Zr, and Y) by analyzing certified standard reference igneous rocks. (iii) Portable Magnetic Susceptibilimeter (pMS, Bartington MS2K system) to constrain the mineralogical contribution of the samples. The operational conditions for these three methods were tested and optimized by analyzing five unprepared surfaces of igneous rocks ranging from a coarse-grained alkaline granite to a fine-grained porphyric diorite and hence, covering variable grain sizes, mineralogical contents, and whole-rock geochemical compositions. For pMS and PXRF tools, one hundred analyses were conducted as a 10 cm × 10 cm square grid on each sample. Bootstrap analysis was implemented to establish the best grid size sampling to reach an optimized reproducibility of the whole-rock signature. For PXRF analysis, averaged compositions were compared to PXRF analysis on press-pellets and laboratory WD-XRF analysis on fused disk and solution ICP-OES (for major) and solution-ICPMS (for trace element concentrations). Ultimately, this workflow was applied in the field on granitoids from three Roman quarrying sites in the Lavezzi archipelago (southern Corsica) and tested against the Bonifacio granitic War Memorial, for which its provenance is established. Our results confirm this information and open the door to geoarchaeological provenance studies with a high spatial resolution.
AB - We present a workflow to conduct a full characterization of medium to coarse-grained igneous rocks, using portable, non-invasive, and reproducible approaches. This includes: (i) Image Analysis (IA) to quantify mineral phase proportions, grain size distribution using the Weka trainable machine learning algorithm. (ii) Portable X-ray fluorescence spectrometer (PXRF, Bruker Tracer IV) to quantify the whole-rock's chemical composition. For this purpose, a specific calibration method dedicated to igneous rocks using the open-source CloudCal app was developed. It was then validated for several key elements (Si, Al, K, Ti, Ca, Fe, Mn, Sr, Ga, Ba, Rb, Zn, Nb, Zr, and Y) by analyzing certified standard reference igneous rocks. (iii) Portable Magnetic Susceptibilimeter (pMS, Bartington MS2K system) to constrain the mineralogical contribution of the samples. The operational conditions for these three methods were tested and optimized by analyzing five unprepared surfaces of igneous rocks ranging from a coarse-grained alkaline granite to a fine-grained porphyric diorite and hence, covering variable grain sizes, mineralogical contents, and whole-rock geochemical compositions. For pMS and PXRF tools, one hundred analyses were conducted as a 10 cm × 10 cm square grid on each sample. Bootstrap analysis was implemented to establish the best grid size sampling to reach an optimized reproducibility of the whole-rock signature. For PXRF analysis, averaged compositions were compared to PXRF analysis on press-pellets and laboratory WD-XRF analysis on fused disk and solution ICP-OES (for major) and solution-ICPMS (for trace element concentrations). Ultimately, this workflow was applied in the field on granitoids from three Roman quarrying sites in the Lavezzi archipelago (southern Corsica) and tested against the Bonifacio granitic War Memorial, for which its provenance is established. Our results confirm this information and open the door to geoarchaeological provenance studies with a high spatial resolution.
KW - Geoarchaeology
KW - Granite discrimination
KW - PXRF
KW - ML-Image segmentation
KW - Magnetic susceptibility
KW - Roman quarry
M3 - Article
VL - 129
JO - Journal of Archaeological Science
JF - Journal of Archaeological Science
SN - 0305-4403
M1 - 105376
ER -