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Centre for Marine and Environmental Research (CIMA)
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Permian stratigraphy and palynology of the Lower Karoo Group in Mozambique: a 2020 perspective
Publication . Lopes, Gilda; Pereira, Zélia; Fernandes, Paulo; Marques, João; Mendes, Márcia; Götz, Annette E.
ABSTRACT: In the past decade, the increase in the number of palynological works in Mozambique documents the significance of palynology in dating the late Palaeozoic basins in this region of southwestern Gondwana. The new information gained mainly from the study of the Moatize-Minj ova Coal Basin is the basis for a better understanding of the regional biostratigraphy, as well as of palaeoenvironmental and palaeoclimatic conditions during the Permian. Here we provide a review on the Permian palynostratigraphy and its implications for lithostratigraphic correlation of Lower Karoo basins in Mozambique. The new biostratigraphic information leads to the conclusion that an age update for the lithostratigraphic units established for the Lower Karoo in Mozambique (Virzi, Moatize, and Matinde formations) is most needed. The Cisuralian palynological association in Mozambique is characterized by long-range taxa recorded since the middle Cisuralian (Sakmarian to Artinskian) (Alisporites spp., Cannanoropollis spp., Horriditriletes spp., Laevigatosporites spp., Potonieisporites spp., Protohaploxypinus spp.). Several first occurrences are also recorded in the late Cisuralian (Kungurian) (e. g., Cirratriradites africanensis, Marsupipollenites triradiatus, and Vittatina spp.). The Guadalupian association is mainly characterized by taxa that extend their range since the Cisuralian (e. g., Alisporites spp., Cirratriradites africanensis, Guttulapollenites hannonicus, Horriditriletes ramosus, Kraeuselisporites enormis, Lueckisporites virkkiae, Limitisporites monstruosus, Marsupipollenites striatus, M. triradiatus, Pakhapites fusus, Platysaccus papilionis, Thymospora pseudothiessenii, and Weylandites lucifer), with only few first occurrences (Lueckisporites virkkiae, Striatopodocarpites cancellatus, and S. fusus) and last occurrences (Cirratriradites africanensis, Limitisporites monstruosos) being recorded. The Lopingian palynological association includes most of the taxa described for the Guadalupian. In contrast, Corisaccites alutas, Indotriradites niger, Klausipollenites schaubergeri, Lunatisporites pellucidus, Osmundacidites senectus, Polypodiisporites spp., P. mutabilis, and Protohaploxypinus microcorpus are recorded for the first time. Indication of the proximity to the Permian-Triassic Boundary is supported by the occurrence of Klausipollenites schaubergeri, Protohaploxypinus microcorpus, and Osmundacidites senectus in the upper part of the Matinde Formation. Based on the palynological data, the oldest rock unit, the Virzi Formation, was deposited in the Permian (middle Cisuralian), and no older sedimentary rocks are currently known for the Lower Karoo Group in Mozambique. The palynological associations described also indicate that the Authors' deposition of the Moatize Formation occurred from the middle Cisuralian to the latest Guadalupian/early Lopingian, whilst the deposition of the Matinde Formation lasted from the late Guadalupian to the latest Lopingian. Thus, the boundary between both formations is assumed to be diachronous.
The age of the first pulse of continental rifting associated with the breakup of Pangea in Southwest Iberia: new palynological evidence
Publication . Vilas Boas, Margarida; Paterson, Niall W.; Pereira, Zélia; Fernandes, Paulo; Cirilli, Simonetta
ABSTRACT: In this work, we report the first palynological age for the base strata of the Silves Sandstones of the Silves Group in the Algarve Basin, located in Southern Portugal. The group is the oldest sedimentary unit of the Algarve Basin and was deposited unconformably over late Pennsylvanian turbidites of the Mira Formation, which were folded and faulted during the Variscan Orogeny. The Silves Group comprises a detrital red bed succession, representing the earliest phase of sedimentation associated with the initial rifting of Pangaea. Macrofossils are rare, occurring predominantly in the top layers of this group, and do not accurately constrain the age of the entire group's deposition. From an outcrop exposed in the central Algarve, a grey mudstone bed positioned 2.5 m above the Variscan unconformity plane yielded palynomorphs that date the beginning of sedimentation in this basin to the early Carnian age (Late Triassic). The moderately well preserved and low-diversity palynological association comprises Aulisporites astigmosus, Enzonalasporites densus, Ovalipollis pseudoalatus, Samaropollenites speciosus, Tulesporites briscoensis and Vallasporites ignacii, among others, and is indicative of an early Carnian age.
The Late Permian in the Muarádzi Sub-basin, Moatize-Minjova Basin, Mozambique: multidisciplinary palaeoenvironmental characterization [Resumo]
Publication . Lopes, Gilda; Pereira, Zélia; Fernandes, Paulo; Mendes, Márcia; Marques, João; Jorge, Raul CG Santos
ABSTRACT: A study involving lithofacies, palynofacies, and palynological analysis is presented for the Muarádzi
Sub-basin. This sub-basin is part of the Moatize-Minjova Basin (MMB), a crucial Karoo aged coalfield
in Mozambique previously situated in the southern-central part of Gondwana.
Late Permian palaeoenvironmental evolution of the Matinde Formation in the Muarádzi Sub-basin, Moatize-Minjova Basin, Mozambique
Publication . Lopes, Gilda; Pereira, Zélia; Fernandes, Paulo; Mendes, Márcia; Marques, João; Jorge, Raul CG Santos
ABSTRACT:A multidisciplinary study involving lithofacies analysis, palynofacies, and palynology is presented for the Muaradzi Sub-basin. This sub-basin is part of the Moatize-Minjova Basin (MMB), an important Karoo aged coalfield in Mozambique. A total of 99 core samples from 3 coal exploration boreholes (DW11, DW21, and DW141) were analysed and all the successions were assigned a Lopingian age based on palynology. According to the data, in the Muar ' adzi Sub-basin, a vast lowland fluvial setting existed with floodplains and wetlands, in an area controlled by tectonic movements associated with a continental rifting phase. Typical vegetation of the Glossopteris Province is recorded in the palynological assemblages of this sub-basin, which allowed for the characterization of a flora dominated by glossopterids (Protohaploxypinus and Striatopodocarpites) and gymnosperm pollen (Alisporites). Other palynomorphs revealed the presence of gingkoales, ferns (Filicopsida), sphenopsids, and lycopsids in the area, indicating a typical lowland setting. Humid and warm climates, associated with higher CO2 atmospheric levels, promoted the growth of widespread vegetation that led to the development of the thick coal beds in anoxic to dysoxic depositional environments.
The age and depositional environments of the lower Karoo Moatize Coalfield of Mozambique: insights into the postglacial history of central Gondwana
Publication . Fernandes, Paulo; Hancox, J.; Mendes, Márcia; Pereira, Zélia; Lopes, Gilda; Marques, João; Jorge, Raul CG Santos; Albardeiro, Luís
SUMÁRIO: Quatro sondagens realizadas na Bacia Carbonífera de Moatize (Moçambique) foram alvo de
estudos palinoestratigráficos e paleoambientais, permitindo a determinação da idade da sucessão estratigráfica do Karoo inferior desta bacia. Os dados forneceram, também, conhecimentos sobre a idade das camadas de carvão, evolução dos ambientes sedimentares e condições paleoclimáticas nesta parte do Supercontinente Gondwana desde o final da glaciação do Paleozoico superior (Guadalupiano inferior) até à fronteira Pérmico-Triásico. Duas fases deposicionais foram reconhecidas relacionadas com importantes eventos tectónicos regionais. A primeira registou a mudança de um leque deltaico de deglaciação para ambientes de delta lacustre e a deposição das camadas de carvão Sousa Pinto e Chipanga em pântanos das margens de lagos durante o Roadiano-Wordiano. A segunda fase está relacionada com os sistemas fluviais de elevada carga sedimentar, e a deposição das camadas de carvão Bananeiras, Intermédia, Grande Falésia e André em planícies de inundação durante o Wordiano (Guadalupiano) ao Lopingiano.
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Funding agency
Fundação para a Ciência e a Tecnologia
Funding programme
6817 - DCRRNI ID
Funding Award Number
UIDP/00350/2020