Understanding the evolution of marginal sea systems throughout the last glacial cycle under natural forcing mechanisms represents a critical field of inquiry within marine sciences. The development of proxies for paleoenvironmental reconstruction in localized low-latitude marine realm is a valuable research endeavor. Here we present a new sedimentary record obtained via piston coring from the western terminal section of the Xisha Trough, in the northwest South China Sea. This record is characterized by high-resolution X-ray fluorescence (XRF) core scanning and radiocarbon age dating, enabling detailed reconstruction of depositional history and assessment of relative paleoclimatic and paleoenvironmental changes during Marine Isotope Stage 3 (MIS3).
Preliminary findings of interest include: (1) a pronounced increase in sedimentation rate during ca. 14.4 – 13.1 cal. kyr. BP, identified as a millennial-scale pulse potentially linked to intensified hydrodynamic conditions driven by global meltwater influx event 1A during the last deglaciation; (2) relatively low amplitude variations in elemental concentrations during the intervals ca. 56.2 – 21.5 cal. kyr. BP and ca. 11.3 – 2 cal. kyr. BP, contrasted with higher amplitude fluctuations observed between ca. 21.5 and 11.3 cal. kyr. BP; and (3) identification of three significant inflection points in the Ca/Ti and Rb/Sr elemental ratio curves at ca. 56, 21.5, and 13.1 cal. kyr. BP, respectively.
This study provides a near-continuous depositional record since ca. 55.6 cal. kyr. BP, thereby contributing valuable insights into the evolutionary history of the western terminal section of the Xisha Trough in the northwest South China Sea. Furthermore, these findings enhance the understanding of natural variability and its influence on sedimentary environments within low-latitude marginal sea influenced by the Asian Monsoon.