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- Follow that blade!- Petroarchaeological proxies as indicators of human mobility during the Copper age of the SW of the Iberian Peninsula: Vila Nova de Sao Pedro case study (Portugal)Publication . Jordão, Patrícia; Neves, César; Mesquita Soares, Sofia; Morgado-Rodríguez, Antonio; Diniz, Mariana; Arnaud, José M.ABSTRACT: Petroarchaeological proxies of blades are a powerful tool for the study of mobility in prehistoric populations to deliver more information on the network relationships of exchange, particularly during the Copper age. However, it is only recently that the first petroarchaeological studies have begun in the SW of the Iberian Peninsula, concerning Recent Prehistory. A sampling of blades from Vila Nova de Sao Pedro, one of the main fortified settlements in Portuguese Estremadura, was used for petrographic and geochemical study. Following the same protocol, geological samples of flint and also igneous rocks were analysed. Additionally, a techno-typological approach was combined in order to characterize the blades types in circulation. This preliminary study traced the diverse and complex dynamics of blade production, which involved the collection of the most readily available Rio Maior flint and the regionally selected Caxarias flint. There were no significant differences in knapping techniques for these two types of flint. The most distant oolitic varieties from Subbetic Cordillera (within 500 km) and the igneous rocks from the Iberian Piryte Belt (within 250 km), particularly for large blades, were not debitated at the site. Due to the high numbers of those types of materials at the site, Vila Nova de Sao Pedro most likely played a significant role in the complex mobility networks of large blades, establishing itself as an aggregating site and possibly a distributor of these artefacts to the Southwest of the Iberian Peninsula. Considering the proximity and the quality of Rio Maior flint sources but also to the amount of raw materials at the site sourced from a long distance, this study shows that mobility is more influenced by cultural motivations than by the availability or quality of raw materials.
- The palynology of the Upper Triassic-Lower Jurassic in the Algarve and Lusitanian basins, PortugalPublication . Vilas Boas, Margarida; Cirilli, Simonetta; Pereira, Zélia; Duarte, Luis; Fernandes, PauloABSTRACT: High-resolution palynological analyses from the Algarve and Lusitanian basins (Portugal) provide a refined biostratigraphical framework and palaeoenvironmental reconstruction for the Late Triassic-Early Jurassic transition. In the Algarve Basin, three new palynozones (AT, SC, and CP) characterise the Silves Group from the early Carnian to early Hettangian, documenting the first Iberian occurrence of Tulesporites briscoensis and precisely delineating the Triassic-Jurassic Boundary (TJB). In the Lusitanian Basin, three palynozones (CG, IK, and Pm) constrain the Conraria and Pereiros formations to the Norian-Hettangian, with the TJB located at the base of the Pereiros Formation. Palaeoenvironmental reconstructions reveal distinct basin-specific evolutions. The Algarve Basin records an early transition from fluvial (Silves Sandstones) to marginal-marine (lagoonal and pond) settings, evidenced by abundant upper Carnian algal elements and reworked Neoproterozoic algae. Conversely, the Lusitanian Basin reflects a Norian-Hettangian marginal-marine, river-dominated setting, with microforaminiferal linings at the base of the Pereiros Formation marking the earliest marine transgression in the Lusitanian Basin. Quantitatively, both basins show a persistent dominance of xerophytic taxa, indicating a shift toward warmer, seasonally dry conditions across the TJB. Malformed sporomorphs in both records suggest environmental stress potentially linked to Central Atlantic Magmatic Province (CAMP) activity. Comparative analysis reveals that sedimentation initiated earlier in the Algarve (early Carnian) than in the Lusitanian Basin (Norian), suggesting diachronous development during Pangaea breakup. The assemblages show strong affinities with the Onslow Microflora, highlighting the Portuguese margin as a key archive for western Tethyan floral and climatic evolution.
- Terrestrial environmental change across the Permian-Triassic boundary in the Karoo Zambezi Basin, Mozambique: Integrating palynological, sedimentological and carbon isotope evidencePublication . Fernandes, Paulo; Pereira, Zélia; Spangenberg, J. E.; Silva Mendes, Márcia Cristina; Lopes, Gilda; Jorge, Raul C. G. Santos; Albardeiro, Luís; Font, Eric; Adatte, T.; Vennemann, T.; Marques, J.ABSTRACT: The Permian-Triassic boundary (PTB; ca. 252 Ma) marks the most severe biotic crisis in Earth history, yet high-resolution terrestrial records from southeastern Gondwana, outside the Main Karoo Basin of South Africa, remain scarce. We present a multidisciplinary investigation of borehole CIMT-014 from the N'Cond & eacute;dzi Coalfield, Mozambique, which preserves a near-continuous continental succession spanning the PTB within the Karoo Zambezi Basin. Sedimentological, palynological, palynofacies, total organic carbon (TOC), and organic carbon isotope (delta(13)Corg) analyses were integrated to reconstruct environmental, ecological, and carbon-cycle changes across the transition. The uppermost Permian Matinde Formation comprises organic-rich floodplain mudstones, siltstones, and thin coal seams deposited under warm, humid conditions and dominated by Glossopteris-associated gymnosperm floras. Crossing the PTB, these deposits are abruptly replaced by conglomeratic, lacustrine, and fluvial sediments of the C & aacute;dzi Formation. Palynological data document a marked decline of glossopterid and other gymnosperm pollen, followed by a short-lived increase in opportunistic lycophyte and fern spores. Concurrently, palynofacies shift from assemblages rich in non-opaque phytoclasts to assemblages dominated by opaque phytoclasts, while TOC values decline from >40 wt% in coal-bearing intervals to <0.2 wt% in the earliest Triassic succession. A pronounced negative delta(13)Corg excursion of approximately 5.4 parts per thousand occurs across the boundary interval, with values decreasing from -25.0 parts per thousand to a minimum of -30.4 parts per thousand. The magnitude, stratigraphic coherence, and association with floral turnover, cessation of peat formation, and fluvial reorganisation indicate that the isotopic carbon excursion records a major perturbation of the global carbon cycle rather than local diagenetic effects. The isotopic signal is consistent with widespread carbon-cycle disruption linked to Siberian Traps magmatism and associated greenhouse-gas emissions. Our results demonstrate that terrestrial ecosystems in southeastern Gondwana experienced profound ecological and environmental disruption during the end-Permian crisis and establish the Karoo Zambezi Basin of Mozambique as a key archive for correlating continental records of the PTB in Gondwana.