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High resolution age model from sedimentary collected along the southwestern Svalbard margin

This dataset includes updated versions of high-resolution age models derived from six sedimentary cores collected from the southwestern Svalbard margin. The dataset presented here represents a refinement of a previous version (Caricchi et al., 2020; 2022), achieved through correlation of the stratigraphic trends of the ARM/k parameter with the GICC05modelext timescale and the NGRIP record (Rasmussen et al., 2014). Additional refinement was obtained from newly acquired and recalibrated radiometric data, as well as from improved lithological constraints. The dataset enables the calculation of sedimentation rates during glacial and interglacial periods and during short-lived, widespread meltwater pulses and Heinrich-like events, thereby allowing the reconstruction of ice-sheet instability and meltwater events along the Svalbard–Barents Sea margin over the last 60,000 years.

New and compiled palaeomagnetic data from western Ross Sea (Antarctica) spanning the last ca. 10 ka

This dataset includes both original and previously published paleomagnetic data. The new data refer to a marine sediment sequence (ANTA02-AV43 core) collected in the in Wood Bay, located along the coast of Victoria Land, within the western Ross Sea (Antarctica) and spanning the last ca. 10 ka. The formerly published paleomagnetic data from coeval sediment cores refer to the from the RS15‐GC57 core of Truax et al. (2025) collected in the adjacent Robertson Bay, and from the PC18 and PC19 cores of Macrì et al. (2005), recovered from the continental rise of the Wilkes Land basin offshore the coast of East Antarctica. The data from these two latter cores were relocated to the location of the ANTA02-AV43 core with the Noel and Batt (1990) method. The estimated age of the formerly published dataset has been re-evaluated after correlation of paleomagnetic trends with the ANTA02-AV43 core and prediction of geomagnetic variation at the ANTA02-AV43 site according to the CALS10k.2 model of Constable et al. (2016). We then combined the new ANTA02-AV43 dataset with existing Holocene records from sediment cores of comparable resolution (PC18 and PC19) to develop the paleomagnetic “HOLOANTA” stack. This composite record averages paleomagnetic data over the last 10,000 years in 200-year intervals. It includes relative paleointensity (RPI) as well as paleomagnetic inclination and declination data, providing a robust regional Holocene RPI curve alongside directional secular variation (PSV) trends.

Magnetochronostratigraphic data from marine sediments off Patagonia, SE Pacific – cores from expedition MR16-09 Leg 2, Japanese RV Mirai, 2017

Sediment cores PC02, PC03, and PC04 were recovered during the ship expedition MR16-09 Leg 2 of Japanese RV Mirai in 2017 (Murata et al., 2017) using piston corers. For paleo- and rock magnetic analyses clear plastic boxes with a volume of 7 cm3 were pressed into the split halves of the generally 1 m long sections of the sediment cores. X-ray fluoresence (XRF) scans were performed with an Itrax XRF Corescanner (Cox Analytical systems) at Kochi Core Center, Japan (Hagemann et al. 2024). The downcore resolution was set to 5 mm, and the scans were performed with a Mo X-ray tube at 30 kV and 55 mA for a measurement time of 15 s. The Itrax X-ray beam was set to 0.2 mm × 20 mm. Measurements of low-field magnetic susceptibility (klf same as: k-bulk) and its anisotropy (AMS) were performed with an AGICO MFK1-A susceptibility meter. The principal AMS axes Kmax, Kint, and Kmin, the three axes of the anisotropy ellipsoid, were used to calculate the degree of anisotropy, as well as the shape factor of anisotropy. The frequency dependency of magnetic susceptibility was determined with an automated MAGNON Variable Field Susceptibility Meter (VFSM) by measuring magnetic susceptibility at different frequencies with logarithmically equidistant steps at a field amplitude of 250 µT. Susceptibilities of core PC02 samples were measured at 7 frequencies F from 375 Hz to 4775 Hz. Samples from cores PC03 and PC04 were measured at 5 frequencies from 475 to 4775 Hz. The frequency dependency Dk/Dlog(F) then was determined by linear regression of susceptibility k versus the decadal logarithm of frequency F. Values are given as decay rate in percent over one frequency decade (% / decade (F)) relative to the measurement at the lowest frequency. Thus, values obtained are negative. Measurements of the natural remanent magnetization (NRM) and of the anhysteretic remanent magnetization (ARM) were performed with a 2G 755 SRM long-core cryogenic magnetometer. ARMs were produced with a 2G660 single-axis alternating field (AF) demagnetizer using 100 mT alternating field and 50 µT static field. NRMs and ARMs both were stepwise demagnetized with the in-line 3-axes AF demagnetizer of the cryogenic magnetometer. AF steps for NRM: 0, 5, 10, 15, 20, 30, 40, 50, 65, 80, 100 mT. AF steps for ARM: 0, 10, 20, 30, 40, 50, 65, 80 mT. Iso-thermal remanent magnetizations (IRM) were imparted with a 2G 660 pulse magnetizer using 1500 mT for producing a saturation magnetization (SIRM) and -200 mT for remagnetization of the low-coercive fraction. Measurements were performed with a Molyneux spinner magnetometer. Data records were turned into time series by applying the age model for PC03 (Hagemann et al., 2024), correlating PC02 to PC03, and correlating PC04 to PC03 (back to 140 ka) and further using the PISO1500 paleointensity stack (Channell et al., 2009), paleomagnetic data from the Black Sea (Liu et al., 2020, Nowaczyk et al., 2021), and paleoclimatic data from Antarctica (Jouzel et al., 2007; Bazin et al., 2013) for reference for older core sections.

Magnetochronostratigraphic data from sediments in the Drake Passage – cores from expedition PS97, German RV Polarstern, 2016

Sediment cores were recovered during the ship expedition of German RV Polarstern in 2016 (PS97) using piston corers. For paleo- and rock magnetic analyses clear plastic boxes of 20×20×15 mm were pressed into the split halves of the generally 1 m long sections of the sediment cores. In order to determine the direction of the characteristic remanent magnetization (ChRM), demagnetization results of the NRM were subjected to principal component analysis (PCA) according to Kirschvink (1980). The PCA also provided the maximum angular deviation (MAD) as a measure of the precision of the determined ChRM direction. ChRM declinations obtained by PCA were rotated around a vertical axis until the declinations of all samples falling into a circular window of 35° around the direction expected from a geocentric axial dipole (-72.9°) yielded a mean of 0°. ChRM data from core PS97-085-1 (-85-3) were tentatively tilted by +17° (-7°) around the EW axis in order to parallel the maximum in the inclination distribution with the inclination of a geocentric axial dipole field. The anhysteretic susceptibility K(ARM) is defined as the ARM intensity normalised by the static field used for producing the ARM. The anhysteretic susceptibility normalised by the low field bulk susceptibility K(ARM)/klf then is a magnetic grain size proxy with low (high) ratios indicating relatively large (small) magnetite particles. In order to discriminate samples being dominated by low-coercive minerals (magnetite, Fe3O4 and greigite, Fe3S4) from samples being dominated by high-coercive minerals (mostly hematite, Fe2O3), the S-ratio was calculated using S=0.5×(1-[IRM(-200 mT)/SIRM(1500 mT)]). S-ratios range from 0 to 1, with: dominance of magnetite/greigite: 0<<S≤1, and dominance of hematite: 0≤S<<1. As another grain size proxy the ARM intensity was normalised by the SIRM: (1000×ARM/SIRM) with low (high) ratios indicating relatively large (small) magnetite particles. The factor of 1000 is introduced in order to avoid small numbers. Relative paleointensity variations were estimated by three different proxies: slope of NRM vs. ARM of common demagnetization steps (slope(NRM/ARM)), NRM intensity demagnetized with 30 mT normalized with bulk susceptibility klf (pjk(30mT)), and NRM intensity demagnetized with 30 mT normalized with saturation magnetization SIRM (pjs(30mT)). Data records were turned into time series by correlation to dated reference records from Antarctica (Wu et al., 2021) and the Black Sea (Liu et al., 2021).

Paleomagnetic data from Kope-Dagh, Northeast Iran

This dataset includes paleomagnetic data from 70 sampling sites, collected in northeastern Iran during two campaigns carried out in August 2016 and September 2017 (Table 1). The data are supplement to Mattei et al. (2019). Data allow to reconstruct the rotation history of the outer margin of the Eurasia-Arabia collision area represented by the Ala-Dagh, Binalud and Kopeh-Dagh mountain belts. The sampled formations are red beds units from the Lower Cretaceous Shurijeh Fm. and from the Middle-Upper Miocene Upper Red Fm (URF). Paleomagnetic results from all the sampled areas show a homogeneous amount of clockwise (CW) rotations measured in the above-mentioned Formations. These paleomagnetic results suggest that the oroclinal bending process that caused the curvature of Alborz mountain belt in north Iran after the Middle-Late Miocene, also extended to the Ala-Dagh, Binalud and Kopeh-Dagh mountain belts, at the north-eastern border of the Arabia-Eurasia deforming zone. This pattern of vertical axis rotations is inconsistent with the present-day kinematics of the northern Iranian blocks as described by seismicity and GPS data, suggesting that the tectonic processes responsible for the bending of northern Iran mountain chains are no longer active and that the westward motion of the South Caspian basin, and therefore the initiation of opposite strike-slip motion along the Ashk-Abad and Shahrud faults, occurred very recently (∼2My ago).

Paleomagnetic data from Ferdows and Yazd, Central Iran

This dataset includes paleomagnetic data from 19 sampling sites, collected in central Iran during two sampling campaigns carried out in April 2011 (Yazd) and November 2011 (Ferdows). The data are supplement to Mattei et al. (2020). The sites were collected along two tectonic structures representative of the main tectonic features of central Iran: the Yazd fold system located in an area dominated by the occurrence of NNW-SSE oriented right-lateral strike slip faults, and the Ferdows fold system that developed at the western termination of the E–W left-lateral strike-slip Dasht-e-Bayaz fault. Paleomagnetic results show opposite vertical-axis rotations related to the different orientation and sense of movement of strike-slip fault systems, suggesting that in Central Iran the N–S oriented right-lateral and E–W oriented left-lateral strike-slip faults play significant roles in accommodating the Arabia-Eurasia convergence, by rotating counterclockwise and clockwise in the horizontal plane, respectively.

Rock magnetic data from sediments from the Arkhangelsky Ridge, SE Black Sea: I - cores from expedition M72/5, German RV Meteor, 2007

This data publication includes standard rock magnetic data related to concentration, coercivity and magneto-mineralogy versus depth from six sediment cores (M72/5-22GC3, M72-5-22GC4, M72-5-22GC6, M72-5-22GC8, M72-5-24GC3, M72-5-25GC1), collected at the Arkhangelsky Ridge in the Southeastern Black Sea during the marine expedition M72/5 of the German research vessel RV METEOR (in May 2007). The data are related to publications by Liu et al. (2018, 2019, 2020), Liu (2019) and Nowaczyk et al. (2012, 2013, 2018, 2021a, b). Sediment cores were recovered using gravity corers. For paleo- and rock magnetic analyses clear plastic boxes of 20×20×15 mm were pressed into the split halves of the generally 1 m long sections of the sediment cores. Data are provided as six ASCII files (.dat, one for each core) with metadata header, followed by 12 data columns and are decribed in the associated data description file (pdf).

Rock magnetic data from sediments from the Arkhangelsky Ridge, SE Black Sea, II - cores from expedition MSM33, German RV Maria S. Merian, 2013

This data publication includes standard rock magnetic data related to concentration, coercivity and magneto-mineralogy versus depth from twelve sediment cores recovered from the Arkhangelsky Ridge in the Southeastern Black Sea, German RV Maria S. Merian expedition MSM33 in 2013: MSM33-51-3, MSM33-52-1, MSM33-53-1, MSM33-54-3, MSM33-55-1, MSM33-56-1, MSM33-57-1, MSM33-60-1, MSM33-61-1, MSM33-62-2, MSM33-63-1, MSM33-64-1. The data are related to publications by Liu et al. (2018, 2019, 2020), Liu (2019) and Nowaczyk et al. (2012, 2013, 2018, 2021a, b). Sediment cores were recovered using gravitiy and piston corers. For paleo- and rock magnetic analyses clear plastic boxes of 20×20×15 mm were pressed into the split halves of the generally 1 m long sections of the sediment cores. Data are provided as 12 ASCII files (.dat, one for each core) with metadata header and are decribed in the associated data description file (pdf).

Paleosecular variation data for marine isotope stage 6 from SE Black Sea sediments

This data publication includes stacked paleomagnetic data, inclinations, declinations, and relative paleointensities, for the time interval 120 to 180 ka, comprising data from twelve sediment cores recovered from the Arkhangelsky Ridge in the Southeastern Black Sea; German RV Meteor expedition M72/5 in 2007: M72/5-22GC6, M72/5-22GC8; German RV Maria S. Merian expedition MSM33 in 2013: MSM33-51-3, MSM33-52-1, MSM33-54-3, MSM33-56-1, MSM33-57-1, MSM33-60-1, MSM33-61-1, MSM33-62-2, MSM33-63-1, MSM33-64-1. The data are also described in Nowaczyk et al. (2021). Sediment cores were recovered using gravitiy and piston corers. For paleo- and mineral-magnetic analyses clear plastic boxes of 20×20×15 mm were pressed into the split halves of the generally 1 m long sections of the sediment cores. Data are provided as six ASCII files (.dat, one for each core) with metadata header, followed by 12 data columns and are decribed in the associated data description file (pdf).

Paleo- and rock magnetic data from cores MSM33-53-1, M72-5-22GC4, M72-5-25GC1 from the southeastern Black Sea

This data publication includes paleo and rock magnetic data from three sediment cores, MSM33-53-1, M72-5-22GC4, M72-5-25GC1, collected in the southeastern Black Sea during the marine expeditions M72/5 of the German research vessel RV METEOR (in 2007) and MSM33 of the German research vessel RV Maria S. Merian (in 2013). The data are supplement to Nowaczyk et al. (2020) and have already been described in Liu et al. (2018, 2019, 2020), Liu (2019) and Nowaczyk et al. (2012, 2013). The cores were sampled at intervals between 1.7 and 3.0 cm. Core M72/5-22GC4 was also continuously subsampled using u-channels. All material was subjected to detailed paleo- and rock magnetic analyses. As a main result the Laschamps geomagnetic excursion at around 41 ka could be revealed (Nowaczyk et al., 2012, 2013, Liu et al., 2020). This feature of the geomagnetic field was characterized by a short but full reversal and very low intensities of the Earth’s magnetic field. However, data is more or less compromised due to the post-depositional precipitation of the magnetic iron suphide greigite (Fe3S4), mainly depending on water depth of the coring sites. Provided data demonstrate the impact of greigite as well as the differences between discrete sample and u-channels (Nowaczyk et al., 2020). Data are provided as several ASCII files providing most relevant rock magnetic and paleomagnetic parameters, the age model as well as detailed information on the location, water depth, cruises and dates.

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