Canadian Journal of Earth Sciences Late Tortonian - Piacenzian multi-proxy record of Asian southwest monsoon intensification: Evidence from Coastal Makran, SE Iran Journal: Canadian Journal of Earth Sciences Manuscript ID cjes-2018-0071.R1 Manuscript Type: Article Date Submitted by the 22-Aug-2018 Author: Complete List of Authors: Modarres, Mohammad; Iranian National Institute for Oceanography and Atmospheric Science Alizadeh KetekDraft Lahijani, Hamid; Iranian National Institute for Oceanography and Atmospheric Science, Marine Geology Keshavarz Farajkhah, Nasser; Research Institute of Petroleum Industry Lahaye, Yann; Geologian tutkimuskeskus Rehfeld, Kira; Institute of Environmental Physics, Universität Heidelberg Manttari, Irmeli; Geologian tutkimuskeskus Naderi-Beni, Abdolmajid; Iranian National Institute for Oceanography and Atmospheric Science, Marine Geology Ojala, Antti ; Geologian tutkimuskeskus Moradpour, Mehran; Research Institute of Petroleum Industry Asian Southwest Monsoon, Coastal Makran, Tortonian- Piacenzian, Keyword: Spectral Gamma- Ray, Volume Magnetic Susceptibility Is the invited manuscript for consideration in a Special Climate Change: Evidence from the geological records in the Middle East Issue? : https://mc06.manuscriptcentral.com/cjes-pubs Page 1 of 57 Canadian Journal of Earth Sciences 1 Late Tortonian - Piacenzian multi-proxy record of Asian southwest monsoon intensification: 2 Evidence from Coastal Makran, SE Iran 3 M. H. Modarres1 , H. A. K. Lahijani2 , N. Keshavarz3, Y. Lahaye4, K. Rehfeld5, I. 4 Manttari6, A. Naderi-Beni7, A. Ojala8, M. Moradpour9 5 1Iranian National Institute for Oceanographic and Atmospheric Sciences, No.3, Tehran, IR. Iran, 6 [email protected] 7 2Iranian National Institute for Oceanographic and Atmospheric Sciences, No.3, Tehran, IR. Iran, 8 [email protected] 9 3Research Institute of Petroleum Industry, Tehran, IR. Iran, [email protected] 10 4Geological Survey of Finland, P. O. Box 96, 02151 Espoo, Finland, [email protected] 11 5Institute of Environmental Physics, Universität Heidelberg, [email protected] 12 6Geological Survey of Finland, P. O. Box 96, 02151 Espoo, Finland, 13 [email protected] 14 7Iranian National Institute for Oceanographic and Atmospheric Sciences, No.3, Tehran, IR. Iran, 15 [email protected] 16 8Geological Survey of Finland, P. O. Box 96, 02151 Espoo, Finland, [email protected] 17 9Research Institute of Petroleum Industry, Tehran, IR. Iran, [email protected] 18 19 Corresponding author: M. H. Modarres,Draft PhD student at Iranian National Institute for 20 Oceanographic and Atmospheric Sciences, No.3, Tehran, IR. Iran, Tel. +989128431411; Email 21 address: [email protected] 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 1 https://mc06.manuscriptcentral.com/cjes-pubs Canadian Journal of Earth Sciences Page 2 of 57 47 Abstract: 48 This study presents a long-term, multi-proxy reconstruction of Asian southwest monsoon during 49 the Tortonian to Piacenzian based on a 4.78 Ma record from Coastal Makran, NW Gulf of Oman 50 in SE Iran. Integration of humidity proxies (clay minerals, Th/K, volume magnetic susceptibility 51 and grain size analysis), marine redox- sensitive (Th/U), total organic matter (TOM), carbonate 52 content, 87Sr/86Sr, and spectral-gamma ray conducted here provide valuable information that fill 53 the existing gap in marine palaeoclimate records during the studied period within the region. 54 The results show that a strong winter monsoon condition associated with relatively low 55 precipitation and subsequently low physical and chemical weathering dominated the region during 56 the late Tortonian- late Messinian (7.65 to 5.83 Ma). A few episodes of intense physical and 57 chemical weathering related to high precipitation,Draft however, is observed during this period (6.23 58 and 6.01 Ma) consistent with increased organic matter input from continental reservoirs to the 59 Oceans. In addition, latest Messinian (5.82 to 5.33 Ma) to Zanclean- Piacenzian (5.33 to 2.87 Ma) 60 is indicated with a strong summer monsoon accompanied with a relatively wetter condition and 61 higher physical and chemical weathering that resulted in the high detrital input into the basin. This 62 higher weathering period is associated with the highest rate of Himalayan uplifting that caused the 63 enhanced precipitation. Using Wavelet analysis of spectral gamma-ray, revealed notable 64 periodicities at 750 Ka and 1.7 Ma with significant periodicities centered around 5.75 to 6.03 Ma 65 over the latest Messinian- Zanclean. Comparison with palaeoclimate archives from other sites, 66 points to a teleconnection with respect to precipitation, weathering and productivity especially 67 during Messinian- Zanclean transition. 68 KEYWORDS: Multi-proxy Reconstruction; Asian Southwest Monsoon; Coastal Makran; 69 Tortonian- Piacenzian, Spectral Gamma- Ray, Volume Magnetic Susceptibility 70 71 1. Introduction 2 https://mc06.manuscriptcentral.com/cjes-pubs Page 3 of 57 Canadian Journal of Earth Sciences 72 The Asian Monsoon, an atmospheric circulation pattern, governs the climatic conditions of the 73 entire Asia. It is comprised of the Indian Summer Monsoon (ISM), East Asian monsoon, and Asian 74 southwest monsoon subsystems (Fleitmann et al., 2003; Gupta, 2003; Liu et al., 2003; Wang et al., 75 2003; Wang et al., 2005; Fleitmann et al., 2007; Wang et al., 2008; Lovett, 2010; Reuter et al., 76 2013). In the northwest Gulf of Oman where the coastal Makran is located, social and economic 77 growth depends mostly upon Asian southwest monsoonal rains for agriculture and even small 78 climatic variations in this atmospheric circulation can result in severe drought and floods that affect 79 large numbers of people (Webster et al., 1998; Kumar et al., 2005; Cook et al., 2010; Reuter et al., 80 2013; Hamzeh et al., 2015; Miller et al., 2016). Therefore, it is becoming increasingly necessary 81 to provide a precise record of climate change with respect to variation in southwestern Asian 82 monsoon as a large-scale atmospheric circulationDraft within the region. Late Tortonian - Piacenzian 83 (7.65-2.87 Ma) is the critical times of changing monsoon intensity that is correspondence to the 84 development of the Asian monsoon system related to Himalayan uplift dated back to the Neogene 85 (Hodell et al., 1991; Prell and Kutzbach, 1992; Prell et al., 1992; Zhisheng et l., 2001). Several 86 records around the world reveal the Asian monsoon intensification in the context of glacial- 87 interglacial oscillations during this time. Late Tortonian-Messinian (7.65 to 5.33 Ma) is marked 88 by the intensification of the Asian winter monsoon possibly due to increased elevation of Tibet- 89 Himalaya, followed by a long-term cooling that is synchronous with strengthening in biological 90 pumping likely occurred between ∼7 Ma until ∼5.5 Ma (Hodell and Kennett, 1986; Jansen et al., 91 1990; Zhisheng et al., 2001; Prell and Kutzbach, 1992; Warren and Kutzbach, 1992; Zhisheng et 92 al., 2011). In addition, evidence reveals a decrease in sea level associated with glaciations so that 93 it was reached from ∼10 m falling to at least 30 m during 6.14 Ma to 5.26 Ma (Hodell et al., 2001). 94 Instead, Zanclean-Piacenzian (∼5.33 to 2.87 Ma) is known for the intensification of the Asian 3 https://mc06.manuscriptcentral.com/cjes-pubs Canadian Journal of Earth Sciences Page 4 of 57 95 summer monsoon and a generally high weathering condition governed specially during the early 96 Zanclean (Prell and Kutzbach; Warren and Kutzbach, 1992; Suc et al., 1995; Zhisheng et al., 97 2015). 98 The reversal in monsoon (summer and winter) winds at the end of Messinian and beginning of 99 Zanclean associated with cooler-dried and warmer-humid periods have been reported in some parts 100 of the world using multi- proxy climatic investigations. To reconstruct this reversal in our region, 101 we need robust multi-proxy records for climate to reconstruct the intensity of the Asian southwest 102 monsoon climatic subsystem, which might be varied significantly throughout the Neogene. In 103 order to understand the past variations in the Asian southwest monsoon and amount of monsoonal 104 precipitation, many paleoclimatological investigations have been conducted using different 105 archives and proxies like cave stalagmitesDraft (Fleitmann et a.l, 2007), lake cores (Hamzeh et al., 106 2015), and marine cores (Gupta et al., 2003; Staubwasser et al., 2003, Miller et al., 2016). 107 However, they all studied the past climate variability at orbital-to-millennial scales during 108 Quaternary period so that pre-Quaternary monsoon variability and dynamics likely linked to 109 changes in external forcing and internal forcing remain obscure within the region. On the contrary, 110 several investigations have been conducted with respect to both East Asian monsoon and Indian 111 Summer monsoon in the Arabian Sea, Indian sub-continent, semi-arid western Himalaya and 112 Karakoram, and the Tibetan plateau (Enzel et al., 1999; Richards et al., 2000; Ricketts et al., 2001; 113 Owen et al., 2002a; Owen et al., 2002b; Seong et al., 2007; Chen et al, 2008; Ao et al, 2016).These 114 investigations cover both Quaternary and pre-Quaternary periods. Hence, it is increasingly 115 necessary to conduct multi-proxy record of Asian southwest monsoon intensification during pre- 116 Quaternary helping substantially our understanding of Asian monsoon system and its subsystem 117 throughout the Asia