02475nas a2200301   4500000000100000008004100001260001500042653003700057653001400094653002800108653003700136100001500173700001700188700001900205700001500224700001500239700001900254700002000273700002500293700001800318700001800336245011600354856004100470300001400511490000700525520162700532020001402159       2017                            d  c2017/04/0110aeastern equatorial Pacific Ocean10amagnetite10arelative paleointensity10aremanence acquisition efficiency1 aLiang Chen1 aDavid Heslop1 aAndrew Roberts1 aLiao Chang1 aXiang Zhao1 aHelen McGregor1 aGianluca Marino1 aLaura Rodriguez-Sanz1 aEelco Rohling1 aHeiko Pälike00aRemanence acquisition efficiency in biogenic and detrital magnetite and recording of geomagnetic paleointensity  uhttps://doi.org/10.1002/2016GC006753  a1435-14500 v183 a<p> Abstract Relative paleointensity (RPI) variations of Earth\textquoterights magnetic field are widely used to understand geomagnetic field behavior and to develop age models for sedimentary sequences. RPI estimation is based on a series of assumptions. One key assumption that is rarely considered is that all magnetic particles in the sediment acquired a magnetization in an identical manner. In this paper, we test this assumption for sediments from the eastern equatorial Pacific Ocean that record well-documented global RPI variations over the last ?780 kyr. The magnetization is carried by two stable single domain magnetic components, which we identify as magnetite magnetofossils and titanomagnetite nanoparticle inclusions within larger silicate particles. By analyzing signals carried by the two components separately, we determine for the first time that magnetic nanoparticle inclusions can cause their host particles to record reliable but inefficient sedimentary paleomagnetic signals. The magnetization carried by biogenic magnetite is acquired more efficiently than that carried by the nanoparticle inclusions. Variations in the concentration of both components are modulated climatically so that they record nearly identical RPI signals. In many sediment types, there is no correlation between the concentrations of different magnetic components so that variable remanence acquisition efficiency will complicate RPI recording. Our work demonstrates that detailed assessment of paleomagnetic recording by each constituent magnetic component needs to become a routine part of sedimentary RPI analysis.</p>  a1525-2027