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A biomagnetostratigraphy for the Lower Triassic is constructed, using the ammonoid biostratigraphy from Arctic Boreal successions. Combined thermal and alternating fi eld demagnetization determines the Triassic magnetic fi eld polarity in 86% of specimens, with 36% showing linear trajectory line fi ts and the remainder showing great-circle trends toward the characteristic magnetization. Mean pole directions for the Deltadalen (λ = 50°, ϕ = 159°, dp/dm = 3.9°/5.1°), Lusitaniadalen (λ = 56°, ϕ = 163°, dp/dm = 4.4°/5.4°), and Vendomdalen (λ = 57°, ϕ = 143°, dp/dm = 4.4°/5.4°) members fall close to the European Lower Triassic apparent polar wander path. Mean directions for two of these membermeans pass the reversal test. The remanence is predominantly carried by magnetite. The polarity stratigraphy, when integrated with the ammonoid and meager conodont data, is similar to that determined from successions in the Sverdrup Basin (Canada). The Permian-Triassic boundary post-dates a pronounced palynofl oral turnover and predates a short duration reverse magnetozone (LT1n.1r). In the correlated Shangsi section (in South China), LT1n.1r occurs after the fi rst appearance datum (FAD) of H. parvus, but in the Arctic is within the Otoceras boreale Zone. The late Griesbachian to early Smithian is mostly reverse polarity, with three normal-polarity intervals, overlain by mid and late Smithian normal polarity. The Spathian contains four reverse-polarity intervals, the oldest one within the early Spathian with the remainder in the late Spathian. The transition into the Anisian is within the uppermost reverse magnetozone, a feature documented in other sections of this age. The polarity pattern is correlated to other marine sections, indicating the robustness of the biomagnetostratigraphic composite and its utility in calibrating Lower Triassic time.

Users of biochar in the field require this product to reliably meet its declared specifications.For the first time, this work investigated, whether these specifications could be reproducibly obtained as a sole function of the thermal history of the biomass feedstock during slow pyrolysis, irrespective of the type and scale of the production unit. Using volatile matter content as a proxy for a wider set of biochar quality parameters, biochar from units at scales from grams to hundreds of kilograms, representing three main types of slow pyrolysis units (fixed bed, screw reactor and rotary kiln) were investigated. For the first time we showed that comparable biochar could be produced by these very different pyrolysis units, with good reproducibility within individual as well as among separate production runs.

[1] Mineral magnetic measurements are used to distinguish ice-rafted debris (IRD) sources and climate cycles spanning Marine Isotope Stage (MIS) 3 and MIS2 in core MD95-2006, from the Barra Fan, NE Atlantic. Distinct magnetic properties are displayed by IRD from the Laurentide ice sheet (LIS) (high susceptibility (c), low isothermal remanent magnetization (IRM), low coercivity and the Verwey transition), the British ice sheet (BIS) (high c, high IRM, medium coercivity and suppressed Verwey transition) and the ambient background sediment (low c and low IRM). A magnetic unmixing model quantifies proportions of the IRD sources during Greenland Stadial (GS) 16 to GS3 (57.3 to 22.6 ka B.P.) spanning Heinrich Event (H) 5 to H2. The magnetic model suggests LIS IRD is only dominant within an interval during GS9, assigned to H4. Prior to H4 low proportions of BIS IRD suggest the BIS was not able to deliver significant amounts of IRD into the marine system. Following H4, proportions of BIS IRD during stadials increase, suggesting growth of the BIS during the latter stages of MIS3, with further expansion of the BIS during MIS2. LIS IRD within H2 is masked by BIS IRD input. Climatically driven anhysteretic remanent magnetizations reflect the short Dansgaard-Oeschger cycles between H5 and H4, while the proportions of hard magnetic minerals reflect the longer-term Bond cycles.