Heat Flux-Based Emissivity Measurement

A method for measuring the emissivity of a surface using heat flux sensors is described. The emissivity is calculated by directly measuring the heat flux passing through the surface using a heat flux sensor. Unlike calorimetric techniques, it does not require accounting for parasitic heat losses or knowing the temperature history of the sample. This technique allows emissivity measurements of newly developed variable emissivity surfaces, including electrostatic devices which cannot be directly measured using optical techniques. It can measure both passive and active thermal control coatings, and can evaluate many surfaces on the same substrate simultaneously. An experimental setup is detailed and results are presented for emissivity measurements of both active and passive surfaces using commercially available heat flux sensors. Errors are estimated for these measurements. A space-based experiment is also described and results of pre-flight testing are presented

A new stratigraphic framework and constraints for the position of the Paleocene-Eocene boundary in the rapidly subsiding Hanna Basin, Wyoming

The Paleocene–Eocene strata of the rapidly subsiding Hanna Basin give insights in sedimentation patterns and regional paleogeography during the Laramide orogeny and across the climatic event at the Paleocene–Eocene Thermal Maximum (PETM). Abundant coalbeds and carbonaceous shales of the fluvial, paludal, and lacustrine strata of the Hanna Formation offer a different depositional setting than PETM sections described in the nearby Piceance and Bighorn Basins, and the uniquely high sediment accumulation rates give an expanded and near-complete record across this interval. Stratigraphic sections were measured for an ∼1250 m interval spanning the Paleocene–Eocene boundary across the northeastern syncline of the basin, documenting depositional changes between axial fluvial sandstones, basin margin, paludal, floodplain, and lacustrine deposits. Leaf macrofossils, palynology, mollusks, δ13C isotopes of bulk organic matter, and zircon sample locations were integrated within the stratigraphic framework and refined the position of the PETM. As observed in other basins of the same age, an interval of coarse, amalgamated sandstones occurs as a response to the PETM. Although this pulse of relatively coarser sediment appears related to climate change at the PETM, it must be noted that several very similar sandstone bodies occur with the Hanna Formation. These sandstones occur in regular intervals and have an apparent cyclic pattern; however, age control is not sufficient yet to address the origin of the cyclicity. Signs of increased ponding and lake expansion upward in the section appear to be a response to basin isolation by emerging Laramide uplifts