Deglacial Spike

The aragonite compensation depth (ACD) fluctuated considerably during the last glacial to Holocene with a dominant pteropod preservation spike during deglacial, which is prominently seen in three well dated cores covering the Andaman Sea, northeastern Indian Ocean. Resolving the precise time period of the preservation spike of pteropods is not known which is crucial for stratigraphic correlation and also for understanding the driving mechanism. Isotopic and foraminiferal proxies were used to decipher the possible mechanism for its preservation in the Andaman Sea. The poor preservation/absence of pteropods during Holocene in the Andaman Sea may have implications on ocean acidification driven by enhanced atmospheric CO 2 concentration. Strengthening of summer monsoon and resultant high biological productivity may also have played a role in poor pteropod preservation. The deglacial pteropod spike is characterized by high abundance/preservation of the pteropods between 19 and 15 cal. ka BP associated with very low atmospheric CO 2 concentration. Isotope data suggest the prevalence of glacial environment with reduced sea surface temperature, upwelling and enhanced salinity during the pteropod preservation spike. Total planktic foraminifera and Globigerina bulloides abundances are low during this period implying weakened summer monsoon and reduced foraminiferal productivity. Based on the preservation record of pteropods, it is inferred that ACD was probably deepest (>2900 m) during 16.5 cal. ka BP. The synchronous regional occurrence of the pteropod preservation spike in the Andaman Sea as well as in the northwestern Indian Ocean can possibly be employed as a potential stratigraphic marker.

The aragonite compensation depth (ACD) fluctuated considerably during the last glacial to Holocene with a dominant pteropod preservation spike during deglacial, which is prominently seen in three well dated cores covering the Andaman Sea, north-eastern Indian Ocean. Resolving the precise time period of the preservation spike of pteropods is not known which is crucial for stratigraphic correlation and also for understanding the driving mechanism. Isotopic and foraminiferal proxies were used to decipher the possible mechanism for its preservation in the Andaman Sea. The poor preservation/absence of pteropods during Holocene in the Andaman Sea may have implications on ocean acidification driven by enhanced atmospheric CO 2 concentration. Strengthening of summer monsoon and resultant high biological productivity may also have played a role in poor pteropod preservation. The deglacial pteropod spike is characterized by high abundance/preservation of the pteropods between 19 and 15 cal. ka BP associated with very low atmospheric CO 2 concentration. Isotope data suggest the prevalence of glacial environment with reduced sea surface temperature, upwelling and enhanced salinity during the pteropod preservation spike. Total planktic foraminifera and Globigerina bulloides abundances are low during this period implying weakened summer monsoon and reduced foraminiferal productivity. Based on the preservation record of pteropods, it is inferred that ACD was probably deepest (>2900 m) during 16.5 cal. ka BP. The synchronous regional occurrence of the pteropod preservation spike in the Andaman Sea as well as in the northwestern Indian Ocean can possibly be employed as a potential stratigraphic marker.

The aragonite compensation depth (ACD) fluctuated considerably during the last glacial to Holocene with a dominant pteropod preservation spike during deglacial, which is prominently seen in three well dated cores covering the Andaman Sea, northeastern Indian Ocean. Resolving the precise time period of the preservation spike of pteropods is not known which is crucial for stratigraphic correlation and also for understanding the driving mechanism. Isotopic and foraminiferal proxies were used to decipher the possible mechanism for its preservation in the Andaman Sea. The poor preservation/absence of pteropods during Holocene in the Andaman Sea may have implications on ocean acidification driven by enhanced atmospheric CO 2 concentration. Strengthening of summer monsoon and resultant high biological productivity may also have played a role in poor pteropod preservation. The deglacial pteropod spike is characterized by high abundance/preservation of the pteropods between 19 and 15 cal. ka BP associated with very low atmospheric CO 2 concentration. Isotope data suggest the prevalence of glacial environment with reduced sea surface temperature, upwelling and enhanced salinity during the pteropod preservation spike. Total planktic foraminifera and Globigerina bulloides abundances are low during this period implying weakened summer monsoon and reduced foraminiferal productivity. Based on the preservation record of pteropods, it is inferred that ACD was probably deepest (>2900 m) during 16.5 cal. ka BP. The synchronous regional occurrence of the pteropod preservation spike in the Andaman Sea as well as in the northwestern Indian Ocean can possibly be employed as a potential stratigraphic marker.

The aragonite compensation depth (ACD) fluctuated considerably during the last glacial until the Holocene with a dominant pteropod preservation spike during the deglacial period, which is prominently seen in three well-dated cores covering the Andaman Sea, northeastern Indian Ocean. The precise time period of the preservation spike of pteropods is not known but this knowledge is crucial for stratigraphical correlation and also for understanding the driving mechanism. Isotopic and foraminiferal proxies were used to decipher the possible mechanism for pteropods preservation in the Andaman Sea. The poor preservation/absence of pteropods during the Holocene in the Andaman Sea may have implications for ocean acidification, driven by enhanced atmospheric CO2 concentration. Strengthening of the summer monsoon and the resultant high biological productivity may also have played a role in the poor preservation of pteropods. The deglacial pteropod spike is characterized by high abundance/prese...

The aragonite compensation depth (ACD) fluctuated considerably during the last glacial to Holocene with a dominant pteropod preservation spike during deglacial, which is prominently seen in three well dated cores covering the Andaman Sea, northeastern Indian Ocean. Resolving the precise time period of the preservation spike of pteropods is not known which is crucial for stratigraphic correlation and also for understanding the driving mechanism. Isotopic and foraminiferal proxies were used to decipher the possible mechanism for its preservation in the Andaman Sea. The poor preservation/absence of pteropods during Holocene in the Andaman Sea may have implications on ocean acidification driven by enhanced atmospheric CO 2 concentration. Strengthening of summer monsoon and resultant high biological productivity may also have played a role in poor pteropod preservation. The deglacial pteropod spike is characterized by high abundance/preservation of the pteropods between 19 and 15 cal. ka BP associated with very low atmospheric CO 2 concentration. Isotope data suggest the prevalence of glacial environment with reduced sea surface temperature, upwelling and enhanced salinity during the pteropod preservation spike. Total planktic foraminifera and Globigerina bulloides abundances are low during this period implying weakened summer monsoon and reduced foraminiferal productivity. Based on the preservation record of pteropods, it is inferred that ACD was probably deepest (>2900 m) during 16.5 cal. ka BP. The synchronous regional occurrence of the pteropod preservation spike in the Andaman Sea as well as in the northwestern Indian Ocean can possibly be employed as a potential stratigraphic marker.