Additional co-authors: TJ Heaton, AG Hogg, KA Hughen, KF Kaiser, B Kromer, SW Manning, RW Reimer, DA Richards, JR Southon, S Talamo, CSM Turney, J van der Plicht, CE Weyhenmeyer

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IntCal13 and Marine13 radiocarbon age calibration curves 0-50,000 years cal BP

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

A survey is given of the dimensions and composition of the present continental crust. The abundances of immobile elements in sedimentary rocks are used to establish upper crustal composition. The present upper crustal composition is attributed largely to intracrustal differentiation resulting in the production of granites senso lato. Underplating of the crust by ponded basaltic magmas is probably a major source of heat for intracrustal differentiation. The contrast between the present upper crustal composition and that of the Archean upper crust is emphasized. The nature of the lower crust is examined in the light of evidence from granulites and xenoliths of lower crustal origin. It appears that the protoliths of most granulite facies exposures are more representative of upper or middle crust and that the lower crust has a much more basic composition than the exposed upper crust. There is growing consensus that the crust grows episodically, and it is concluded that at least 60% of the crust was emplaced by the late Archean (ca. 2.7 eons, or 2.7 Ga). There appears to be a relationship between episodes of continental growth and differentiation and supercontinental cycles, probably dating back at least to the late Archean. However, such cycles do not explain the contrast in crustal compositions between Archean and post-Archean. Mechanisms for deriving the crust from the mantle are considered, including the role of present-day plate tectonics and subduction zones. It is concluded that a somewhat different tectonic regime operated in the Archean and was responsible for the growth of much of the continental crust. Archean tonalites and trond-hjemites may have resulted from slab melting and/or from melting of the Archean mantle wedge but at low pressures and high temperatures analogous to modern boninites. In contrast, most andesites and subduction-related rocks, now the main contributors to crustal growth, are derived ultimately from the mantle wedge above subduction zones. The cause of the contrast between the processes responsible for Archean and post-Archean crustal growth is attributed to faster subduction of younger, hotter oceanic crust in the Archean (ultimately due to higher heat flow) compared with subduction of older, cooler oceanic crust in more recent times. A brief survey of the causes of continental breakup reveals that neither plume nor lithospheric stretching is a totally satisfactory explanation. Speculations are presented about crustal development before 4000 m.y. ago. The terrestrial continental crust appears to be unique compared with crusts on other planets and satellites in the solar system, ultimately a consequence of the abundant free water on the Earth.

The geochemical evolution of the continental crust

National Institute of Standards and Technology における超伝導研究及び生活

Chemical composition and evolution of the upper continental crust: Contrasting results from surface samples and shales

Application of the 40ar/39ar ages of hornblende for tracking ice rafted detritus provenance around antarctica

Geochemical constraints on li-rich authigenic mineralization of lacustrine deposits in the mcdermitt caldera

Early Pleistocene Marine Isotope Stage (MIS)‐31 (1.081–1.062 Ma) is a unique interval of extreme global warming, including evidence of a West Antarctic Ice Sheet (WAIS) collapse. Here we present a new 1,000‐year resolution, spanning 1.110–1.030 Ma, diatom‐based reconstruction of primary productivity, relative sea surface temperature changes, sea‐ice proximity/open ocean conditions and diatom species absolute abundances during MIS‐31, from the Scotia Sea (59°S) using deep‐sea sediments collected during International Ocean Discovery Program (IODP) Expedition 382. The lower Jaramillo magnetic reversal (base of C1r.1n, 1.071 Ma) provides a robust and independent time‐stratigraphic marker to correlate records from other drill cores in the Antarctic Zone of the Southern Ocean (AZSO). An increase in open ocean species Fragilariopsis kerguelensis in early MIS‐31 at 53°S (Ocean Drilling Program Site 1,094) correlates with increased obliquity forcing, whereas at 59°S (IODP Site U1537; this study) three progressively increasing, successive peaks in the relative abundance of F. kerguelensis correlate with Southern Hemisphere‐phased precession pacing. These observations reveal a complex pattern of ocean temperature change and sustained sea surface temperature increase lasting longer than a precession cycle within the Atlantic sector of the AZSO. Timing of an inferred WAIS collapse is consistent with delayed warmth (possibly driven by sea‐ice dynamics) in the southern AZSO, supporting models that indicate WAIS sensitivity to local sub‐ice shelf melting. Anthropogenically enhanced impingement of relatively warm water beneath the ice shelves today highlights the importance of understanding dynamic responses of the WAIS during MIS‐31, a warmer than Holocene interglacial.

Latitudinal Variance in the Drivers and Pacing of Warmth During Mid‐Pleistocene MIS 31 in the Antarctic Zone of the Southern Ocean

Advances in the understanding of neogene mammalian fauna in the pampean region (central argentina) through revising “biozone” hypotheses based on new dates and biochronological analyses

of the Thesis Evaluation of Ar-Ar ages of Individual Mica Grains for Provenance Studies of Loess, Long Island, NY by Jian Zhong Master of Science in Geosciences State University of New York at Stony Brook 2001 Loess in a one-meter thick section on the SUNY Stony Brook Campus has been studied for grain size distribution and provenance. The loess provenance has been evaluated using single crystal Ar/Ar muscovite and biotite ages. The grain size distribution of loess shows three modes at fine sand (250 microns), silt (20 microns), and clay (<2 microns). There are also occasional pebbles up to 5 cm in diameter in the loess. The size distribution of the clay and silt fractions of the sediment resemble that of loess in many parts of the world. The size distribution of the fine sand in the loess resembles that of the immediately underlying glacial sand unit and the sand in the underlying gravely till. It is proposed that sand in the loess on Stony Brook campus might be wind blown sand or derived from the underlying sand and till by the combined action of cryoturbation and faunalturbation. Mica has been also dated for samples in a section from Caumsett State Park, Lloyd Harbor, New York about 25 miles west of the campus that includes Cretaceous sands, glacial outwash sand and gravel, and loess.

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Sidney R. Hemming

Papers

Application of the 40ar/39ar ages of hornblende for tracking ice rafted detritus provenance around antarctica

Geochemical constraints on li-rich authigenic mineralization of lacustrine deposits in the mcdermitt caldera

Latitudinal Variance in the Drivers and Pacing of Warmth During Mid‐Pleistocene MIS 31 in the Antarctic Zone of the Southern Ocean

Advances in the understanding of neogene mammalian fauna in the pampean region (central argentina) through revising “biozone” hypotheses based on new dates and biochronological analyses

Evaluation of Ar-Ar ages of Individual Mica Grains for Provenance Studies of Loess, Long Island, NY