Foraminiferal Analysis Related to Paleoceanographic Changes of Arafura Sea and Surrounding During Holocene

• Published in: BULLETIN OF THE MARINE GEOLOGY
• Main Authors: Luli Gustiantini, Swasty Aninda Piranti, Rina Zuraida, Sangmin Hyun, Duddy A.S. Ranawijaya, F.X. Harkinz Hendro Prabowo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Marine Geological Institute of Indonesia 2018
• Subjects: Paleoceanographic changes; upwelling; foraminiferal analysis; Arafura Sea; Oceanography; GC1-1581; Geology; QE1-996.5; Planktonic foraminifera
• Online Access: https://doi.org/10.32693/bomg.33.2.2018.571; https://doaj.org/article/63df8b644caf43ceb32c12de4fca53e5

Arafura Sea is located between Papua and Australia as a part of Sahul Shelf. It is strongly influenced by ITF, ITCZ replacement, monsoon, and ENSO circulation that interplay with local mechanism. To understand the paleoceanographic parameter changes during Holocene, we conducted foraminiferal quantitative analysis from a 152 cm length sediment core (Aru–07), in every 10 cm interval. This sediment core was retrieved from 134o00’33.6” E, 5o55’51.59” S, by RV Geomarin 3 belongs to Marine Geological Institute. Geochronology of the sediment was reconstructed based on 2 AMS 14C age dates, analyzed on organic samples. We identified 129 species of benthic and 24 species of planktonic foraminifera that is dominated by planktonic specimens with average of 53.14%. Predominant species are Globigerina bulloides (16.16%), Globigerinoides ruber (11.18%), and Neogloboquadrina dutertrei (5.65%). Benthic type is dominated by genera Bolivina, Bulimina, and Uvigerina by 25.86% (average). This might suggest eutrophic condition associated with carbon-rich or low oxygen level (dysoxic) condition. Single linkage cluster analysis revealed 3 paleoenvironmental zones, are: Zone I: older than 3.9 kyr BP, characterized by depleted oxygen level and nutrient enrichment compared to that of younger zone. Zone II: 3.9 – 2 kyr BP, characterized by oxygen content enrichment and deeper thermocline layer, related to the sea level rise during more neutral or La Niña like condition. Zone III: younger than 2 kyr BP, represent shallower thermocline layer, higher productivity which might be related to upwelling, and dysoxic condition. Sea level might be declined that related to more El Niño like condition. Keywords: Paleoceanographic changes, upwelling, foraminiferal analysis, Arafura Sea Laut Arafura berlokasi di antara Papua dan Australia sebagai bagian dari Paparan Sahul. Kondisi iklim sangat dipengaruhi oleh ITF, perpindahan ITCZ, monsun, dan ENSO yang berinteraksi dengan mekanisme lokal. Untuk memahami perubahan parameter oseanografi selama Holosen, ...