Karakteristik Morfologi Dasar Laut dan Hubungannya dengan Ketebalan Sedimen dan Kecepatan Arus di Selat Flores, Selat Lamakera, Selat Boling, dan Selat Alor

Abstract

<strong>Characteristics of Sea Bottom Morphology and Their Relationships with Sediment Thickness and Current Speed in the Straits of Flores, Lamakera, Boling, and Alor. </strong> The morphology of the seabed of a strait may affect sedimentary deposits and current speeds in the strait. The Straits of Flores, Lamakera, Boling, and Alor connect the Flores Sea and Savu Sea in East Nusa Tenggara Province. This study aimed to determine the characteristics of seabed morphology and its relation to sediment thickness and current speed in the straits. Single Beam Echosounder and SubBottom Profiler were used to measure depth of waters and subsurface. The results showed that the seabed of the Flores Strait was basin-shaped at a depth of about 250 m, while the seabed at the connections between the Straits of Boling, Lamakera, and Alor was a ridge leading to the Flores Sea and Savu Sea with depths up to 3,000 m. The thickness of the sedimentary sediments in the Flores Strait reached 50 m, while in the Straits of Boling, Lamakera, and Alor sedimentary deposits were not visible. In the Flores Strait which was characterized by narrow strait, the current speed ranged from 0.3 to 3.8 m/s. The descriptions of subsurface conditions in these straits can be used for navigation of ships that will cross the straits, especially vessels of more than 2,000 tons. The narrow strait morphology causes the mass of water in this region to have a high current speed. Therefore, the sedimentation occurs only in the Flores Strait due to its basin-shaped seabed.

Estimasi Sea Surface Topography Menggunakan Data Satelit Altimetri di Laut Indonesia Timur Periode 2016-2021

“…Salah satu fenomena tersebut adalah Arus Lintas Indonesia (Arlindo) atau lebih dikenal sebagai Indonesian Through Flow (ITF). ITF adalah aliran massa air dari Samudera Pasifik ke Samudera Hindia yang disebabkan oleh perbedaan tekanan antara dua samudera tersebut (Hasanudin, 1998). Salah satu laut di Indonesia yang dilewati fenomena ITF adalah Laut Indonesia Timur yang mencakup Laut Banda, Laut Flores, Laut Sulawesi, Laut Maluku, Laut Seram, Laut Halmahera, Laut Timor, Laut Arafuru, dan Laut Sawu.…”

“…Gambar 1. Indonesian Through Flow (ITF) (Gordon, 2005) Dengan berbagai faktor yang mempengaruhi fenomena ini, seperti arus, angin, hingga suhu air laut menjadikan fenomena ITF mempunyai aliran air yang kuat dan volume yang besar (Hasanudin, 1998). Aliran air yang kuat dan volume yang besar dari ITF mengakibatkan aliran air menjadi tidak sederhana sehingga terjadi perubahan dalam distribusi massa air di Laut Indonesia Timur.…”

Analysis of Chlorophyll-a Variability in the Eastern Indonesian Waters Using Sentinel-3 OLCI from 2020-2021

“…The Indonesian waters are significant in influencing the global climate system and inter-ocean interactions. This influence is attributed to the flow of water masses originating from the western Pacific Ocean towards the southeast Indian Ocean, driven by variations in water mass pressure, a phenomenon known as the Indonesian Through Flow (ITF) (Hasanudin, 1998;Sprintall & Révelard, 2014). The flow directs waters towards the Indian Ocean, leading to the replacement of flowing waters by the North Pacific and South Pacific thermocline waters.…”

Estimation of Sea Surface Topography Using Jason-3 Satellite Altimetry Across the Eastern Indonesian Seas in a period of 2016 to 2021

“…Marine phenomena such as the Indonesian Through Flow (ITF) also have a significant influence on the East Indonesian Sea. ITF is the massive water flow from the Pacific Ocean to the Indian Ocean as a result of the difference in pressure between the two oceans [2]. Strong water flows and large volumes of ITF can cause changes in the distribution of water masses in the Indonesian Sea.…”