Paleoenvironment of Limestone Based on Foraminifera Content of Ako Area, Pasangkayu Regency, West Sulawesi Province

• Main Authors: Fiska Safana, Tati Fitriana, Nurhikmah Supardi
• Format: Article in Journal/Newspaper
• Language: English
• Published: LPPM Universitas Tadulako 2024
• Subjects: Foraminifera; Ancient Environment; Lithology; Age; Planktonic foraminifera
• Online Access: https://bestjournal.untad.ac.id/index.php/sciencetech/article/view/17298; https://doi.org/10.22487/sciencetech.v1i2.17298

Introduction: In the marine environment there are types of Protista called foraminifera which are divided into 2 (two) which are called planktonic foraminifera and benthonic foraminifera, where planktonic foraminifera live by being anchored in mud or sediment. Method: The abundance of fossil planktonic foraminifera and benthonic foraminifera in the Ako area is very diverse, namely: 192 species of planktonic foraminifera and 381 species of benthonic foraminifera. Results and Discussion: The living environment of foraminifera in the study area is in the middle neritic zone with a depth of 30-100 m, where sunlight can still penetrate so that nutrients and oxygen for foraminifera are very sufficient. Salinity varies between 30-40% and temperature is divided into hot and warm climates. In hot climates, planktonic foraminifera such as Globorotalia Tumida and Globorotalia Menardii are found, while in warm climates Orbulina bilobata and Globorotalia Dutertrei are found. Benthonic foraminifera living at this depth include Cibicides Wuellerstorfi and Lenticulina orbicularis. Changes in the marine environment in the middle neritic zone are influenced by strong wave dynamics, as well as sea level fluctuations that cause regression and transgression, lifting sedimentary rocks to the surface. Conclusion: The foraminifera fossils in the Ako area are highly diverse, with 192 species of planktonic foraminifera and 330 species of benthonic foraminifera. The shells of foraminifera in this area are relatively large because nutrients from sunlight are abundant. Its paleoenvironment is in the middle neritic zone with a depth of 30-200 m, salinity of 3-30%, and temperature divided into hot and warm climates. Changes in the marine environment in this zone are influenced by sea level fluctuations that cause a decrease (regression) and increase (transgression) of sea level, as well as the removal of sedimentary rocks to the surface.