Scientific Drilling; Lake sediments; Paleoenvironment; Indonesia; Paleoclimate; Int. Continental Scientific Drilling Progr. (ICDP); Subsurface Biosphere
Wilke Thomas, Wagner Bernd, Van Bocxlaer Bert, Albrecht Christian, Ariztegui Daniel, Delicado Diana, Francke Alexander, Harzhauser Mathias, Hauffe Torsten, Holtvoeth Jens, Just Janna, Leng Melanie J., Levkov Zlatko, Penkman Kirsty, Sadori Laura, Skinner Alister, Stelbrink Bj?rn, Vogel Hendrik, Wesselingh Frank, Wonik Thomas (2016), Scientific drilling projects in ancient lakes: Integrating geological and biological histories, in Global and Planetary Change
, 143, 118-151.
Russell James M., Bijaksana Satria, Vogel Hendrik, Melles Martin, Kallmeyer Jens, Ariztegui Daniel, Crowe Sean, Fajar Silvia, Hafidz Abdul, Haffner Doug, Hasberg Ascelina, Ivory Sarah, Kelly Christopher, King John, Kirana Kartika, Morlock Marina, Noren Anders, O&apos, Grady Ryan, Ordonez Luis, Stevenson Janelle, von Rintelen Thomas, Vuillemin Aurele, Watkinson Ian, Wattrus Nigel, et al. (2016), The Towuti Drilling Project: paleoenvironments, biological evolution, and geomicrobiology of a tropical Pacific lake, in Scientific Drilling
, 21, 29-40.
Vogel Hendrik, Russell James M., Cahyarini Sri Yudawati, Bijaksana Satria, Wattrus Nigel, Rethemeyer Janet, Melles Martin (2015), Depositional modes and lake-level variability at Lake Towuti, Indonesia, during the past ~29?kyr BP, in Journal of Paleolimnology
, 54(4), 359-377.
Two interlinked proposals seek funds for the Swiss contribution to the Lake Towuti Drilling Project (TDP) that is already partially sponsored and will be executed by the International Continental Scientific Drilling Program (ICDP). One proposal seeks funds for scientific activities and two PhD students of the involved Swiss research groups. Another proposal seeks funds for the Swiss share of costs related to drilling operations that will recover several hundred meters of sediment from Lake Towuti’s subsurface. Lake Towuti (2.5°S, 121°E) is a 560 km2-large and 200-m deep tectonic lake at the downstream end of the Malili lake system, a set of five ancient (1-2 Ma) tectonic lakes located in central Sulawesi, Indonesia. Its location provides an important opportunity to reconstruct long-term terrestrial paleoclimate change in a crucially important yet understudied region- the Western Pacific warm pool, heart of the El Niño-Southern Oscillation. Lake Towuti has high rates of floral and faunal endemism and is surrounded by one of the most diverse tropical forests on Earth, making it a hotspot of Southeast Asian biodiversity. The ultramafic (ophiolitic) rocks and lateritic soils in the catchment provide ferruginous metal substrates that feed a diverse, exotic microbial community in the lake and its sediments, potentially analogous to the microbial ecosystems that operated in the Archean Oceans and on Mars. Therefore, Lake Towuti is a key site for ICDP activities and the TDP will provide valuable new information to understand the climate, biological, and geomicrobiological evolution of this unique system. This Swiss initiative embedded in the overarching ICDP Towuti Drilling Project encompasses two interlinked research modules: Module (A): Climate history: Detailed sedimentology, geochemistry, and mineralogy of drill core from Site 1 (PI’s: Hendrik Vogel & Flavio Anselmetti, U. Bern). This module will provide the temporal succession of lithological variations and contribute the stratigraphic backbone for the master site of the TDP. Detailed lithofacies characterization, paired with high-resolution major element chemistry (XRF core-scanning), and detailed granulometric and mineralogical analysis on the sediment succession, will produce datasets crucial for the reconstruction of climatic and environmental variability and limnological change at high temporal resolutions. Information on sediment geochemistry and mineralogy as well as on climate-induced changes of past limnological conditions will also be beneficial for the geomicrobiological research of Module (B). The sedimentological and geochemical analysis of fluviolacustrine sediments will help characterizing the style and nature of Towuti’s early lake stages, the primordial ooze for today’s biodiversity and endemism. Module (B): Exploring the lacustrine subsurface biosphere (PI’s: Daniel Ariztegui & Massimo Chiaradia, U. Geneva). Microbial activity decreases dramatically below the sediment water interface, yet over long time-scales, this activity has an appreciable impact on sediment composition and on extant biogeochemical cycles. In this module we will examine the activity of the microbial community throughout the sediments. We will provide first-hand information on microbial activity measuring in situ ATP activity immediately after the cores will be retrieved. This bulk data will be compared and blended with more detailed analyses that will be performed by other members of the ICDP project. Laboratory analyses will include Rock-Eval pyrolysis to characterize the bulk nature of the organic matter that is the main support for microbial development. Lake Towuti’s sediments are Fe-rich and thus stand out as an end member microbial habitat. Thus, Fe-isotope analyses will also be performed by the Ph.D. student of this module. These data are anticipated to capture signals of strong water column stratification and anoxia as well as to record information about catchment weathering. Additionally, Zn isotopes will be measured in the same samples providing an independent proxy for productivity changes. This information will be amalgamated with that coming out from Module A to provide a solid picture of the nature of the lithological variations and its relationship with environmental changes.