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Rachel, "Origin and paleoclimatic signifi cance of late Quaternary loess in Nebraska: Evidence from stratigraphy, chronology, sedimentology, and geochemistry" (2008 The spatial variability of particle size abundances in Peoria Loess shows a northwest-to-southeast fi ning in Nebraska, consistent with maps of previous workers that show a northwest-to-southeast thinning of loess. These observations indicate that paleowinds that deposited the loess were from the west or northwest and that the source or sources of Peoria Loess lay to the west or northwest.New mineralogical and geochemical data indicate that the most important sources of loess were likely Tertiary siltstones of the White River and Arikaree Groups, silt facies of Pliocene eolian sediments, and small contributions from Pierre Shale. It is likely that fi ne-grained silts were transported episodically through the Nebraska Sand Hills from

The Killingworth dome of south-central Connecticut occurs at the southern end of the Bronson Hill belt. It is composed of tonalitic and trondhjemitic orthogneisses (Killingworth complex) and bimodal metavolcanic rocks (Middletown complex) that display calc-alkaline affinities. Orthogneisses of the Killingworth complex (Boulder Lake gneiss, 456 ؎ 6 Ma; Pond Meadow gneiss, ϳ ϳ460 Ma) were emplaced at about the same time as eruption and deposition of volcanic-sedimentary rocks of the Middletown complex (Middletown Formation, 449 ؎ 4 Ma; Higganum gneiss, 459 ؎ 4 Ma). Hidden Lake gneiss (339 ؎ 3 Ma) occurs as a pluton in the core of the Killingworth dome, and, on the basis of geochemical and isotopic data, is included in the Killingworth complex. Pb and Nd isotopic data suggest that the Pond Meadow, Boulder Lake, and Hidden Lake gneisses (Killingworth complex) resulted from mixing of Neoproterozoic Gander terrane sources (high 207 Pb/ 204 Pb and intermediate Nd) and less radiogenic (low 207 Pb/ 204 Pb and low Nd) components, whereas Middletown Formation and Higganum gneiss (Middletown complex) were derived from mixtures of Gander basement and primitive (low 207 Pb/ 204 Pb and high Nd) sources. The less radiogenic component for the Killingworth complex is similar in isotopic composition to material from Laurentian (Grenville) crust. However, because published paleomagnetic and paleontologic data indicate that the Gander terrane is peri-Gondwanan in origin, the isotopic signature of Killingworth complex rocks probably was derived from Gander basement that contained detritus from non-Laurentian sources such as Amazonia, Baltica, or Oaxaquia. We suggest that the Killingworth complex formed above an east-dipping subduction zone on the west margin of the Gander terrane, whereas the Middletown complex formed to the east in a back-arc rift environment. Subsequent shortening, associated with the assembly of Pangea in the Carboniferous, resulted in Gander cover terranes over the Avalon terrane in the west; and in the Middletown complex over the Killingworth complex in the east. Despite similarities of emplacement age, structural setting, and geographic continuity of the Killingworth dome with Oliverian domes in central and northern New England, new and published isotopic data suggest that the Killingworth and Middletown complexes were derived from Gander crust, and are not part of the Bronson Hill arc that was derived from Laurentian crust. The trace of the Ordovician Iapetan suture (the Red Indian line) between rocks of Laurentian and Ganderian origin probably extends from Southwestern New Hampshire west of the Pelham dome of northcentral Massachusetts and is coverd by Mesozoic rocks of the Hartford basin. introduction Tectonic models for the origins of terranes in New England have evolved to increasing complexity with the confluence of multiple techniques, including mapping (structure and stratigraphy), igneous and metamorphic petrology, geochemistry, geochronology, geophysics, and isotope geology (Tucker and others, 2001; Mo...