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Abstract--The movements of cultured (n=18) and wild (n=28) juvenile crimson jobfish (Pristipomoides filamentosus) are reported for a known nursery off windward Oahu, Hawaii. The 2 batches of fish were tagged [...]

Detachment faults on the west flank of the Black Mountains (Nevada and California) dip 29[degrees]-36[degrees] and cut subhorizontal layers of the 0.77 Ma Bishop ash. Steeply dipping normal faults confined to the hanging walls of the detachments offset layers of the 0.64 Ma Lava Creek B tephra and the base of 0.12-0.18 Ma Lake Manly gravel. These faults sole into and do not cut the low-angle detachments. Therefore the detachments accrued any measurable slip across the kinematically linked hanging-wall faults. An analysis of the orientations of hundreds of the hanging-wall faults shows that extension occurred at modest slip rates ( Keywords: detachment, Death Valley, Quaternary, extension, tephrochronology.

We present new geologic maps of the Lake Champlain region of west-central Vermont and east-central New York State. This region contains a shallow-crustal section of an Ordovician foreland basin and a far-traveled thrust system that transported the Upper Cambrian-Lower Ordovician platform-sequence, allochthonous rise-facies pelites and arenites and Middle Ordovician basinal shales and flysch. Early foreland and shelf sections are cut by post-depositional cross faults within the thrust system, and the required stratigraphic throw across the cross faults is not matched by the amount they offset the thrust planes. As thrust structures, these cross faults control structural style and kinematics by laterally bounding regions that contrast sharply in amount of thrust imbrication, duplexing, and net transport. The dominant set of normal faults in the autochthon, which had time-correlative slip with the thrust-system cross faults, is oriented parallel to the paleotrench, though there is also a subordinate transverse, linking set. The normal faults developed in response to the migrating flexural forebulge during convergence between the Laurentian margin and the accretionary prism above an outboard-facing subduction zone. Within the thrust system, any prethrust normal faults that were parallel to the paleotrench are largely masked by thrust structures. However, an out-of-sequence thrust, which emplaced shelf rocks above the westernmost allochthon and surrounding parautochthonous shale, may have localized on a paleotrench-parallel normal fault in the outer shelf. We also identify a postthrust normal fault that significantly obscures the original thrust map pattern. Reactivation of synconvergence, prethrust, flexure-induced normal faults adequately explains many otherwise puzzling stratigraphic and structural relationships in the Taconic foreland. Keywords: Champlain Valley, foreland, reactivation, Taconic orogeny, thrust.

To assess potential impacts on receiving systems, associated with storm water contaminants, laboratory 10‐d amphipod (Eohaustorius estuarius) survival toxicity tests were performed using intact sediment cores collected from Paleta Creek (San Diego Bay, CA, USA) on 5 occasions between 2015 and 2017. The approach included deposition‐associated sediment particles collected from sediment traps placed at each of 4 locations during the 2015 to 2016 wet seasons. The bioassays demonstrated wet season toxicity, especially closest to the creek mouth, and greater mortality associated with particles deposited in the wet season compared with dry season samples. Grain size analysis of sediment trap material indicated coarser sediment at the mouth of the creek and finer sediment in the outer depositional areas. Contaminant concentrations of metals (Cd, Cu, Hg, Ni, Pb, and Zn) and organic compounds (polycyclic aromatic hydrocarbons [PAHs], polychlorinated biphenyls [PCBs], and pesticides) were quantified to assess possible causes of toxicity. Contaminant concentrations were determined in the top 5 cm of sediment and porewater (using passive samplers). Whereas metals, PAHs, and PCBs were rarely detected at sufficient concentrations to elicit a response, pyrethroid pesticides were highly correlated with amphipod toxicity. Summing individual pyrethroid constituents using a toxic unit approach suggested that toxicity to E. estuarius could be associated with pyrethroids. This unique test design allowed delineation of spatial and temporal differences in toxicity, suggesting that storm water discharge from Paleta Creek may be the source of seasonal toxicity. Environ Toxicol Chem 2019;39:229–239. © 2019 SETAC [ABSTRACT FROM AUTHOR]