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Paleomagnetic, rock magnetic, or geomagnetic data found in the MagIC data repository from a paper titled: Assessing Paleosecular Variation Averaging and Correcting Paleomagnetic Inclination Shallowing 

Abstract This paper addresses one of the critical questions of scientific inquiry: How do we know when a given data set is representative of the phenomenon being examined? For paleomagnetists, the question is often whether a particular data set sufficiently averaged paleosecular variation (PSV). To this aim, we updated an existing PSV data set that now comprises 2,441 site mean directions from 94 individual studies (PSV10‐24). Minimal filtering for data quality resulted in 1,619 sites from 90 publications. Fitting PSV10‐24 with two newly defined parameters as well as two existing ones form the basis of a Giant Gaussian Process field model (THG24) consistent with the data. Drawing directions from THG24 yields directional distributions predicted for a given latitude allowing a comparison between empirical distributions and the cumulative distribution function generated by the model. This tests whether the observed data adequately averaged out PSV according to THG24. We applied these tests to five data sets from Large Igneous Provinces from the last billion years and find that they are consistent with the THG24 model as well. Sedimentary data sets that may have experienced inclination shallowing can be corrected using an (un)flattening factor that yields directions satisfying THG24 in a newly‐defined, four‐parameter space. This approach builds on the Elongation‐Inclination (E/I) method of Tauxe and Kent (2004),https://doi.org/10.1029/145gm08, so the approach introduced here is called SVEI. We show examples of the use of SVEI and explain how to use this newly developed Python code that is publicly available in the PmagPy GitHub repository. 

Paleomagnetic, rock magnetic, or geomagnetic data found in the MagIC data repository from a paper titled: Flow directions in dikes from anisotropy of magnetic susceptibility data: The bootstrap way 

Paleomagnetic, rock magnetic, or geomagnetic data found in the MagIC data repository from a paper titled: Paleomagnetism of Miocene East African Rift sediments and the calibration of the geomagnetic reversal time scale 

A gas hydrate assessment at International Ocean Discovery Program Expedition 400 drill sites was conducted using downhole logging and core data. Here, we calculate and present the base of gas hydrate stability zone at Expedition 400 drill sites in Baffin Bay, northwest Greenland. We used data from downhole logs and sediment cores from Sites U1603, U1604, U1607, and U1608 to assess hydrate and did not find evidence for the presence of hydrate. At Site U1606, only core data were acquired that showed a decrease in pore water salinity, potentially indicating the presence of hydrate; however, further confirmation was not possible due to the unavailability of downhole logging data. Because of the limitation of the acquired data at the drill sites, a further assessment to confirm the presence of hydrate was not possible. Although hydrate was not identified at any drill sites, hydrate might still be present in the region. 

Paleomagnetic, rock magnetic, or geomagnetic data found in the MagIC data repository from a paper titled: Noise in the quiet zone 

Site U1603 (proposed Site MB-23A) is located at 72°59.04′N, 62°58.83′W in Baffin Bay at 1801 meters below sea level (mbsl), below a protrusion of the northwest Greenland margin shaped by the Melville Bugt Trough Mouth Fan (TMF) (Figure F1). The site targets an expanded drift-channel succession situated on the lower slope between two paleo–ice sheet outlets that represent major drainage routes for the northern Greenland ice sheet (NGrIS) into Baffin Bay (Knutz et al., 2019; Newton et al., 2017, 2021). The drilling strategy was to core a continuous high-resolution record of ice-ocean processes spanning the early late Pleistocene. 

Site U1608 (proposed Site MB-06D) was cored at 74°7.6818′N, 60°58.3172′W at 607 meters below sea level (mbsl) on the middle section of the northwest Greenland shelf, west of the Melville Bay Ridge and graben structures formed during Cretaceous rifting (Figure F1; see Figure F4 in the Expedition 400 summary chapter [Knutz et al., 2025b]). The main coring targets are mounded contourite drift deposits of expected Pliocene age associated with Megaunit B (Knutz et al., 2015, 2019; Aubrey et al., 2021) and overlying sediments of Megaunit A, recording the transition into glacigenic deposits of earliest trough mouth fan (TMF) progradation (Figure F2). The expanded interval of Megaunit B, captured at Sites U1606 and U1608, reflects deposition below a major incised escarpment that is at least 500 m tall and extends into disturbed sediment packages interpreted as mass transport deposits (Figure F3). The base of the contourite drift accumulation is defined by Horizon c1 of probable Late Miocene age (Knutz et al., 2015). Site U1608 ends ~100 m above Horizon c1, which at this location is characterized by an erosional unconformity related to the slope instability that is strongly expressed in the seismic record (Figure F3). In the context of the full development of the Melville Bugt TMF, Site U1608 targeted TMF Seismic Unit 1, which records the first advance of the northwestern Greenland ice sheet (GrIS) onto the continental shelf, which is hypothesized to correspond to the Pleistocene/Pliocene boundary (Knutz et al., 2019) (Figures F2, F3). Combined, the cores from middle shelf Sites U1606 and U1608 access archives of ocean and climate conditions presumably much warmer than today that were buried by glacial deposits representing global cooling and expansion of northern hemisphere glaciers. These sites use the dynamic drift morphology to capture different parts of Megaunit B strata to capture high-resolution records of the Pliocene ocean-climate system at high Arctic latitudes. 

Elucidating the geologic history of the Greenland ice sheet (GrIS) is essential for understanding glacial instability thresholds, identified as major climate system tipping points, and how the cryosphere will respond to anthropogenic greenhouse gas emissions. To address current knowledge gaps in the evolution and variability of the GrIS and its role in Earth’s climate system, International Ocean Discovery Program (IODP) Expedition 400 obtained sedimentary records from Sites U1603–U1608 across the northwest Greenland margin into Baffin Bay where thick Cenozoic sedimentary successions can be directly linked to the evolution of the northern GrIS (NGrIS). The strategy of drilling along this transect was to retrieve a composite stratigraphic succession representing the late Cenozoic era from the Oligocene/early Miocene to the Holocene. The proposed sites targeted high–accumulation rate deposits associated with contourite drifts and potential interglacial deposits within a trough mouth fan system densely covered by seismic data. The principal objectives were to (1) test if the NGrIS underwent near-complete deglaciations in the Pleistocene and assess the ice sheet’s response to changes in orbital cyclicities through the mid-Pleistocene transition, (2) ascertain the timing of the NGrIS expansion and examine a hypothesized linkage between marine heat transport through Baffin Bay and high Arctic warmth during the Pliocene, and (3) provide new understandings of climate-ecosystem conditions in Greenland during the geologic periods with increased atmospheric CO2 compared to preindustrial values, encompassing the last 30 My. The deep time objective was attained by coring at Site U1607 on the inner shelf to 978 meters below seafloor, capturing a succession of mainly Miocene and Oligocene age. The six sites drilled during Expedition 400 resulted in 2299 m of recovered core material, and wireline downhole logging was completed at Sites U1603, U1604, U1607, and U1608. This unique archive will provide the basis for understanding the full range of forcings and feedbacks—oceanic, atmospheric, orbital, and tectonic—that influence the GrIS over a range of timescales, as well as conditions prevailing at the time of glacial inception and deglacial to interglacial periods. We anticipate that the shipboard data and further analytical work on Expedition 400 material can constrain predictive models addressing the GrIS response to global warming and its impending effects on global sea levels. 

Site U1606 (proposed Site MB-17A) was cored at 74°13.9380′N, 61°2.2426′W at 653 meters below sea level (mbsl) on the middle section of the northwest Greenland shelf (Figure F1). The site targets the transition from preglacial contourite drift sediments into glacigenic deposits of the earliest trough mouth fan progradation (Seismic Unit 1), marking the first advance of the northern Greenland ice sheet onto the continental margin (Figure F2). The drilling target was at 411 m core depth below seafloor, Method A (CSF-A), near the base of Megaunit B above Horizon c1 (Figure F3), coring a succession that is complementary to Site U1608. The uppermost 180 m at Site U1606 targets a geographically restricted depositional unit, possibly an erosional remnant, aimed at capturing a stratigraphic record of the preglacial to glacial transition that hypothetically corresponds to the Pleistocene/Pliocene boundary (Knutz et al., 2019). Below 150–180 m CSF-A, Site U1606 targets a 200 m thick sedimentary unit characterized internally by a uniform bundle of tilting strata that converges updip against a fault defining an erosional scarp above Horizon c1 (Figure F3). The seismic geometries imply accumulation of sedimentary drift deposits of Megaunit B over a significantly truncated section of Megaunit C (Knutz et al., 2015). The lower sedimentary unit of Site U1606 has a corresponding section at the base of Site U1608 (Figures F2, F3).