FN Archimer Export Format
PT J
TI Deglacial-Holocene environmental changes at the Pacific entrance of the Strait of Magellan
BT 
AF HARADA, Naomi
   NINNEMANN, Ulysses
   LANGE, Carina B.
   MARCHANT, Margarita E.
   SATO, Miyako
   AHAGON, Naokazu
   PANTOJA, Silvio
AS 1:1;2:2,3;3:4,5;4:6;5:1;6:7;7:4,5;
FF 1:;2:;3:;4:;5:;6:;7:;
C1 Japan Agcy Marine Earth Sci & Technol, Res Inst Global Change, Yokosuka, Kanagawa, Japan.
   Univ Bergen, Dept Earth Sci, N-5007 Bergen, Norway.
   Univ Bergen, Bjerknes Ctr Climate Res, N-5007 Bergen, Norway.
   Univ Concepcion, Dept Oceanog, Concepcion, Chile.
   Univ Concepcion, Ctr Oceanog Res Eastern South Pacific COPAS, Concepcion, Chile.
   Univ Concepcion, Dept Zool, Concepcion, Chile.
   Japan Agcy Marine Earth Sci & Technol, Kochi Inst Core Sample Res, Nankoku, Kochi, Japan.
C2 JAMSTEC, JAPAN
   UNIV BERGEN, NORWAY
   UNIV BERGEN, NORWAY
   UNIV CONCEPCION, CHILE
   UNIV CONCEPCION, CHILE
   UNIV CONCEPCION, CHILE
   JAMSTEC, JAPAN
IF 2.752
TC 9
UR https://archimer.ifremer.fr/doc/00264/37548/36825.pdf
LA English
DT Article
CR MD159 / PACHIDERME
BO Marion Dufresne
DE ;Biogenic components;delta C-13;delta N-15;Planktic foraminifera;Alkenone;Sea surface temperature;Southern Patagonia
AB We show environmental and nitrogen cycle changes between 13 and 2.5 kyr BP (from the latest deglaciation to the Holocene) based on biogeochemical records in a sediment core from the Pacific entrance of the Strait of Magellan. Organic carbon, total nitrogen, and C-37 alkenone contents were low during 13-9 kyr BP but increased rapidly at 8 kyr BP. The relative contribution of tetra-unsaturated C-37 alkenone, used as a salinity proxy, suggests low salinity during 13-9 kyr BP changing to high salinity at 8 kyr BP. Planktic foraminifer data showed that Globigerina bulloides was more abundant during the deglacial-early Holocene than in the mid-late Holocene, whereas abundances of Neogloboquadrina pachyderma showed the opposite pattern. This evidence plus biogenic opal data suggest that sea level rose, surface waters were relatively stratified, and in situ productivity was low except for organisms with opal tests from 13 to 9 kyr BP. Bulk delta N-15 values were high (9-11 parts per thousand) relative to present-day values during the deglacial-early Holocene, with consistently lower values (similar to 7 parts per thousand) after similar to 8 kyr BP. These relatively high delta N-15 values most likely reflect increased nutrient utilization in the Southern Ocean, which resulted in high-delta N-15 water being advected to the Patagonian fjords, although local denitrification caused by the delivery of copious terrestrial materials and organic matter to the ocean cannot be ruled out. By similar to 8 kyr BP continental influences and surface stratification were reduced and characteristic Holocene conditions were established, with increased influence of Southern Ocean water in the western Strait of Magellan. Sea surface temperatures showed millennial-scale changes during the deglaciation and early Holocene, with relatively warm temperatures (11-12 degrees C) corresponding to the Antarctic counterpart of the Younger Dryas cooling event of the Northern Hemisphere. The longer term pattern (similar to 10 kyr time scale) in alkenone-derived sea surface temperatures generally follows orbital changes in insolation during austral spring, suggesting a controlling influence of austral spring insolation on southern Patagonian climate.
PY 2013
PD APR
SO Palaeogeography Palaeoclimatology Palaeoecology
SN 0031-0182
PU Elsevier Science Bv
VL 375
UT 000317704000010
BP 125
EP 135
DI 10.1016/j.palaeo.2013.02.022
ID 37548
ER

EF