PALEOCLIMATE ANALYSIS OF PLIOCENE EPOCH IN NORTH PAPUA WATERS, PACIFIC OCEAN

• Main Author: Bayukaradha Anindito, Reyvangga
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/47323
• Institution: Institut Teknologi Bandung

The northern waters of Papua are one of the entrances of the ITF (Indonesian Through Flow) which brings masses of warm water to the Indian Ocean through Indonesia. As the ITF's entrance to Indonesia, Papua's northern waters are also affected by ENSO (El Niño Southern Oscilation) which is a recurrent climate pattern that involves water circulation and temperature changes in the Pacific Ocean which also affects the climate in Indonesia. Based on the position and role of Papua's northern waters, it is necessary to know how the climate change are occurring in the area. Paleoclimate reconstruction was carried out to determine the climatic conditions and the effect of ENSO on the in the northern waters of Papua during the Pliocene. Paleoclimate reconstruction is carried out using sediment samples which are gravity core data obtained through the 2018 Nusa Manggala Expedition conducted by LIPI. The analysis conducted in this study is granulometry analysis, X-Ray Fluorescence (XRF) analysis, and micropaleontological analysis in the form of foraminifera. Grain size analysis is performed to determine the statistical parameters of sediment’s grain size. XRF analysis is used to determine the chemical elements present in the sample that can be used as a proxy for the variation of rainfall. Foraminifera analysis is performed to determine the relative age and sea surface temperature (SST), and thermocline.. The paleoclimate reconstruction in the study area resulted in the change of ENSO intensity in ~3,15-3,55 M.y.a. interval (Pliocene). In ~3,15-3,21 and ~3,33-3,45 M.y.a. dominated by La Niña, while in ~3,21-3,33 and ~3,45-3,55 M.y.a. dominated El Niño. The ENSO phenomenon has a role in climate and sea water fluctuations in the study area. The decreased intensity of ENSO (dominance of La Niña) results in an increase in sea surface temperature and an increase in rainfall in the study area. While the increased intensity of ENSO (dominated by El Niño) results in a decrease in sea surface temperature and a decrease in rainfall in the study area.