Planktonic foraminiferal biostratigraphy of the Limboto Limestone, Gorontalo Province, Indonesia

Abstract

The limestone research within the Limboto Basin of Gorontalo Province becomes a new challenge, particularly for the study of planktonic foraminiferal biostratigraphy. This study uses the data obtained from the measured section in the north-western part of Limboto Lake. The purpose of this study is to determine the planktonic foraminiferal biozonation and the relative age of Limboto limestones. The analyzed planktonic foraminiferal fossils can be classified as well to moderately preserved of various species, in the context of abundance, categorized as frequent to abundant. There are three recognized planktonic foraminiferal biozones, i.e., two biozones for Miocene age (M13b and M14) and one biozone for Pliocene age (PL1). The Miocene biozones are named as Globorotalia plesiotumida partial range zone (M13b) and Pulleniatina primalis-Globoquadrina dehiscens concurrent range zone (M14), while the name of Pliocene biozone is Globorotalia acostaensis partial range zone (PL1). The results of this study can be a reference to propose an age of Limboto Limestone Formation. Identification and demarcation of the Limboto Limestone Formation are based on the time interval and relative age of the formation based on planktonic foraminifera.

Analisis Lingkungan Purba Batugamping Daerah Limboto Barat Kabupaten Gorontalo

“…Umur batugamping di sekitar Danau Limboto berdasarkan penelitian terakhir yakni Miosen Akhir-Pliosen Awal [10] sedangkan penelitian sebelumnya berumur Pliosen-Pleistosen [11]. Perbedaan umur ini membuat penelitian terakhir mengusulkan nama formasi baru yakni Formasi Batugamping Limboto dari nama formasi sebelumnya yakni Formasi Batugamping Klastik [10,11].…”

“…Penelitian mengenai paleobatimetri batugamping di selatan Danau Limboto pada zona neritik tengah-neritik luar [8,9].Umur batugamping di sekitar Danau Limboto berdasarkan penelitian terakhir yakni Miosen Akhir-Pliosen Awal [10] sedangkan penelitian sebelumnya berumur Pliosen-Pleistosen [11]. Perbedaan umur ini membuat penelitian terakhir mengusulkan nama formasi baru yakni Formasi Batugamping Limboto dari nama formasi sebelumnya yakni Formasi Batugamping Klastik [10,11].Keberadaan batugamping yang ada di bagian tengah Danau Limboto Kabupaten Gorontalo sangat menarik diteliti. Karena Limboto saat ini merupakan danau air tawar padahal batugamping yang terbentuk di sekitar Danau Limboto mencirikan lingkungan laut dengan keterdapatan melimpahkan pecahan koral di batugamping.…”

“…Tongkat Jacob sepanjang 1,5 meter tersebut memiliki interval 10 cm dengan ditandai perbedaan warna mencolok hitam dan putih. Tujuan metode MS ini dilakukan untuk mendapatkan stratigrafi daerah penelitian berdasarkan karakteristik yang berbeda dari masing-masing fasies [3,6,7,10,14].…”

The Analysis of Sliding Surface in Alo Watershed, Gorontalo District, Indonesia

“…Referring to the latest research, the name of new limestone formation is Limboto Limestone Formation. This formation consists of two to three microfacies with shallow marine paleobathymetry that have undergone tectonic uplift [5,6]. The slope on Alo watershed is dominated by gentle slopes with slopes ranging from 8 -15% with a percentage area of 3.14%, and slopes of 15 -25% are 25.74%.…”