Miocene development of the Asian monsoon and oceanographic response in the Bay of Bengal

Lead Research Organisation: University of Nottingham
Department Name: Sch of Geography

Abstract

The Mid Miocene Climate Transition (MMCT, ~13.8 Ma) was an abrupt and permanent episode of global cooling, Antarctic ice sheet expansion and global biotic changes that have been linked by some to erosion and weathering of the Himalaya (e.g. Clift et al. 2008; Armstrong et al. 2011; Kender et al. 2014). The proposed research, to be carried out by PDRA Fox at the University of Nottingham, on new cores collected during IODP Expedition 354 (Bengal Fan), will provide vital information on palaeoceanographic changes in the Bay of Bengal during the mid Miocene including the MMCT (13-16 Ma), and shed new light on the evolution of the Asian monsoon system that affects both the oceanography of this system and Himalayan erosion. In addition to testing the hypothesis of enhanced erosion of the Himalaya at this time, the results of the proposed investigation will provide crucial information for the IODP objective of understanding how the Himalayan-Tibet orogenesis interacted with the Earth's climate over this important interval. This includes forcing of the climate due to palaeoceanographic evolution and atmospheric CO2 uptake, as well as retroaction of the monsoonal climate on the tectonic region via erosion (France-Lanord et al., 2014; Kender et al. 2014). We propose to tackle these hypotheses through high resolution planktonic foraminiferal stable isotope (d18O and d13C) and trace metal (e.g. Mg/Ca) analyses.

Planned Impact

As a participant on IODP expedition 354, I will attend the post cruise sample meeting (ca. 1 month after the cruise) and the post cruise science meeting (ca. 1 year after the expedition). Further engagement will take place at various national and international conferences. Such as the AGU-2015 Fall meeting and Palaeoceanography 2015 which would allow me to communicate the results generated at the University of Leeds to a wide audience and encourage collaboration with other research institutions. Attendance of these meetings will also be followed up with timely publication of results in peer-reviewed journals. The potential of this project is several high impact publications illustrating the significant aspects of the palaeoceanography and palaeoclimatology during an interval of intense orogenesis and climate evolution. It is anticipated that these articles would be collaborative efforts with shipboard and shore-based scientists and will be suitable for inclusion in high impact journals such as Geology, Earth and Planetary Science, and Palaeoceanography.

The IODP has an excellent infrastructure for outreach and education initiatives including an audio-visual library containing interviews and blogs related to each expedition, as well as the highly popular "Teacher at Sea" and "School of Rock" Programs. All of this information is hosted by the IODP Education Portal. Our expedition education program will focus on promoting sea-going research and the science goals of this expedition through the JR's education web portal (http://www.joidesresolution.org/), where podcasts, videos, photo gallery, news releases and daily reports, live ship-to-shore video events, and development of curriculum and video projects from the expedition are featured regularly. The web portal encourages broader participation from students, teachers, families, and the general public in the work and travels of the ship. The site aims to build engagement and welcome everyone to follow along by capitalizing on many social networking tools - including blogs with video and photos, Instagram, Twitter, Facebook, and YouTube. I will keep a blog for the duration of the cruise, and regularly provide twitter updates which will include updates on life on board ship and the scientific background, and the aims and progress of the expedition. It is anticipated that the shipboard scientists, including myself, will actively participate in many broadcasts/webcasts while the ship is at sea and some also during the post-cruise moratorium period. During and after expedition 354 the IODP have invested in two education and outreach posts that will assist me and the expedition 354 science party to better and immediately disseminate the preliminary as well as the final post-cruse results. Namely these are Diana Hanano and also Lisa Strong who will be the cruise Education Officers.

The IODP main web portal already is well connected to the global scientific community and preliminary results and exciting news articles are often published on the IODP website. I intend to exploit the IODP infrastructure to maximize the impact of the research in this proposal. Additionally, in order to be as effective as possible in meeting the knowledge exchange goals outlined in the IODP science plan I will also attend the NERC course on communicating science to the public.

Publications

10 25 50
 
Description The climates of Asia are affected by the extent and height of the Himalayan Mountains and the Tibetan Plateau. Uplift of this region began about 50 Ma, and further significant increases in altitude of the Tibetan Plateau are thought to have occurred through the Miocene and more recently. However, the climatic consequences of this uplift remain unclear. There are contradictory summer monsoon reconstructions that highlight the importance of long continuous sediment records and robust proxies to achieve consensus about the timing of monsoon intensification, which can then potentially be correlated to changing topography in central Asia and the tectonic history of the Himalaya. Expedition 354 to the Bay of Bengal (February-March 2015) cored seven sites along a longitudinal (8oN) transect, and recovered ~1.7 km of sediment spanning the Cenozoic. Sites U1450 and U1451 recovered material from a succession of late Miocene to Recent distal turbidites. We generated paired records of surface and deep d18O and d13C from planktonic and benthic foraminifera spanning 2-8 Ma, which is a record that is included in a paper that is currently being drafted. We use benthic d18O to constrain the biostratigraphic age model produced on the ship, and surface water changes to put constraints on the possible long-term evolution of salinity from the late Miocene to the Pliocene.
Exploitation Route When published, our data will be used by the palaeoclimate community to build a consensus on the long therm changes to the East Asian monsoon, and be used by climate modellers to constrain computational modelling outputs of monsoonal climate with proxy data.
Sectors Education,Other
 
Description The climates of Asia are affected by the extent and height of the Himalayan Mountains and the Tibetan Plateau. Uplift of this region began about 50 Ma, and further significant increases in altitude of the Tibetan Plateau are thought to have occurred through the Miocene and more recently. However, the climatic consequences of this uplift remain unclear. There are contradictory summer monsoon reconstructions that highlight the importance of long continuous sediment records and robust proxies to achieve consensus about the timing of monsoon intensification, which can then potentially be correlated to changing topography in central Asia and the tectonic history of the Himalaya. Expedition 354 to the Bay of Bengal (February-March 2015) cored seven sites along a longitudinal (8N) transect, and recovered ~1.7 km of sediment spanning the Cenozoic. Sites U1450 and U1451 recovered material from a succession of late Miocene to Recent distal turbidites. We generated paired records of surface and deep d18O and d13C from planktonic and benthic foraminifera spanning 2-8 Ma. We use benthic d18O to constrain the biostratigraphic age model produced on the ship, and surface water changes to put constraints on the possible long-term evolution of salinity from the late Miocene to the Pliocene. Results are currently being written up for peer-reviewed publication.
First Year Of Impact 2017
Sector Education,Other