Paleoenvironmental changes related to the variations of the sea-ice coverduring the Late Holocene in an Antarctic fjord (Edisto Inlet, Ross Sea)inferred by foraminiferal association

被引：1

作者：

Galli, Giacomo ^{[1
,2
]}

Morigi, Caterina ^{[2
]}

Melis, Romana ^{[3
]}

Di Roberto, Alessio ^{[4
]}

Tesi, Tommaso ^{[5
]}

Torricella, Fiorenza ^{[6
]}

Langone, Leonardo ^{[5
]}

Giordano, Patrizia ^{[5
]}

Colizza, Ester ^{[3
]}

Capotondi, Lucilla ^{[7
]}

Gallerani, Andrea ^{[7
]}

Gariboldi, Karen ^{[1
]}

机构：

[1] Univ Ca Foscari Venezia, Dipartimento Sci Ambientali Informat & Stat, Via Torino 155, I-30172 Venice, Italy

[2] Univ Pisa, Dipartimento Sci Terra, Via Santa Maria 53, I-56126 Pisa, Italy

[3] Univ Trieste, Dipartimento Matemat & Geosci, Via E Weiss 2, I-34127 Trieste, Italy

[4] Ist Nazl Geofis & Vulcanol INGV, Sez Pisa, Via C,Battisti 53, I-56125 Pisa, Italy

[5] ISP CNR, Ist Sci Polari, Via P Gobetti 101, I-40129 Bologna, Italy

[6] Ist Nazl Oceanog & Geofis Sperimentale OGS, Borgo Grotta Gigante 42-C, I-34010 Trieste, Italy

[7] ISMAR CNR, Ist Sci Marine, Via P Gobetti 101, I-40129 Bologna, Italy

来源：

JOURNAL OF MICROPALAEONTOLOGY | 2023年 / 42卷 / 02期

关键词：

KING GEORGE ISLAND; BENTHIC FORAMINIFERA; TEMPORAL VARIABILITY; VICTORIA LAND; WEDDELL SEA; BAFFIN-BAY; ECOLOGY; CLIMATE; DEEP; PENINSULA;

D O I：

10.5194/jm-42-95-2023

中图分类号：

Q91 [古生物学];

学科分类号：

0709 ; 070903 ;

摘要：

TR17-08, a marine sedimentary core (14.6 m), was collected during 2017 from the Edisto Inlet (Ross Sea, Antarctica), a small fjord near Cape Hallett. The core is characterized by expanded laminated sedimentary sequences making it suitable for studying submillennial processes during the Early Holocene. By studying different well-known foraminifera species (Globocassidulina biora, G. subglobosa, Trifarina angulosa, Nonionella iridea, Epistominella exigua, Stainforthia feylingi, Miliammina arenacea, Paratrochammina bartrami and Portatrochammina antarctica), we were able to identify five different foraminiferal assemblages over the last similar to 2000 years BP. Comparison with diatom assemblages and other geochemical proxies retrieved from nearby sediment cores in the Edisto Inlet (BAY05-20 and HLF17-1) made it possible to distinguish three different phases characterized by different environmental settings: (1) a seasonal phase (from 2012 to 1486 years BP) characterized by the dominance of calcareous species, indicating a seasonal opening of the inlet by more frequent events of melting of the sea-ice cover during the austral summer and, in general, a higher-productivity, more open and energetic environment; (2) a transitional phase (from 1486 to 696 years BP) during which the fjord experienced less extensive sea-ice melting, enhanced oxygen-poor conditions and carbonate dissolution conditions, indicated by the shifts from calcareous-dominated association to agglutinated-dominated association probably due to a freshwater input from the retreat of three local glaciers at the start of this period; and (3) a cooler phase (from 696 years BP to present) during which the sedimentation rate decreased and few to no foraminiferal specimens were present, indicating ephemeral openings or a more prolonged cover of the sea ice during the austral summer, affecting the nutrient supply and the sedimentation regime.

引用

页码：95 / 115

页数：21