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    Site U1334

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    Integrated Ocean Drilling Program (IODP) Site U1334 (7°59.998?N, 131°58.408?W; 4799 meters below sea level [mbsl]) (Fig. F1; Table T1) is located ~380 km southeast of previously drilled Ocean Drilling Program (ODP) Site 1218 (~42 Ma crust) in the central area drilled during the Pacific Equatorial Age Transect (PEAT) program (IODP Expedition 320/321). Site U1334 (~38 Ma crust) is situated ~100 km north of the Clipperton Fracture Zone on abyssal hill topography draped with ~280 m sediment (Fig. F2). The fabric of the abyssal hills within the sites is oriented either due north or slightly east of due north.Water depth in the vicinity of Site U1334 ranges between 5.0 and 5.1 km for the depressions between the abyssal hills. The abyssal hills range between 4.70 and 4.85 km water depth and generally show a thicker and more consistent sediment cover than the basins. In fact, a significant amount of the bathymetric difference between hills and basins is controlled by the amount of sediment cover. The comparison of sediment thickness and clarity of seismic sections led us to select a location on the middle elevation of one of the abyssal plateaus.Site U1334 sediments were estimated to have been deposited on top of late middle Eocene crust with an age of ~38 Ma and target the events bracketing the Eocene–Oligocene transition with the specific aim of recovering carbonate-bearing sediments of latest Eocene age prior to a large deepening of the calcium carbonate compensation depth (CCD) that occurred during this greenhouse to icehouse transition (Kennett and Shackleton, 1976; Miller et al., 1991; Zachos et al., 1996; Coxall et al., 2005). The Eocene–Oligocene transition experienced the most dramatic deepening of the Pacific CCD during the Paleogene (van Andel, 1975), which has now been shown by Coxall et al. (2005) to coincide with a rapid stepwise increase in benthic oxygen stable isotope ratios, interpreted to reflect a combination of growth of the Antarctic ice sheet and decrease in deepwater temperatures (DeConto et al., 2008; Liu et al., 2009).<br/

    Stratigraphic and Petrological Insights into the Late Jurassic– Early Cretaceous Tectonic Framework of the Northwest Pacific Margin

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    Late Jurassic–Early Cretaceous volcano‐sedimentary sequences in the Sorachi, Kumaneshiri, and Yezo groups are exposed in central Hokkaido. The sequences are considered to reflect the Late Mesozoic tectonic history of the northwest Pacific continental margin. Based on the stratigraphic and petrological characteristics of igneous and volcaniclastic rocks of the Sorachi, Yezo, and Kabato groups, Late Jurassic–Early Cretaceous tectonics in central Hokkaido can be divided into six stages. Stage I (Tithonian) is characterized by extensive eruption of tholeiitic basalt accompanied with andesitic volcaniclastic rocks and terrigenous deposits. Seafloor spreading or large igneous province formation occurred near an island arc and/or continent during this stage. In Stage II, island arc volcanic islands were constructed on the basaltic rocks formed during Stage I. Stage III (latest Berriasian‐Valanginian) is characterized by the formation of pull‐apart basins accompanied by seafloor spreading. Widespread upwelling of the asthenosphere below central Hokkaido may have occurred during this stage. After the cessation of in situ volcanism in Stage IV (Hauterivian), submarine island arc volcanism reoccurred in Stage V (Barremian). In Stage VI (Aptian–Campanian), typical active continental margin volcanism occurred and voluminous granitic batholiths were formed in western Hokkaido

    Balance-of-payments-constrained Cyclical Growth with Distributive Class Conflicts and Productivity Dynamics

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    This study builds a dynamic balance-of-payments-constrained (BOPC) model that incorporates the endogenous determination of the economic growth rate, conflictive wage/price distribution, and employment rate. Following the Kaleckian--Marxian literature, wages and commodity prices are determined by the reserve army effect and employment is determined by the reserve army creation effect. The relative strength of these two effects generates different outcomes for the transitional dynamics and comparative statics analysis. In particular, the model shows stability, instability, and a cyclical nature, the latter of concurs with the evidence reported by previous empirical studies

    A Dynamic Analysis of Demand and Productivity Growth in a Two-sector Kaleckian Model

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    This study extends a two-sector Kaleckian model of growth and income distribution by incorporating the dynamics of labour productivity growth. The economy is composed of investment goods and consumption goods producing sectors, with the sectoral demand and productivity growth interaction dynamically formalized. The study analyses the conditions for the cyclical demand and productivity growth phenomena in a two-sector economy. The model reveals that each sector may present a different response in capacity utilization rate to a change in sectoral income distribution. These phenomena are specific to two-sector models, and cannot be observed with a conventional aggregate growth model

    A Dynamic Analysis of Demand and Productivity Growth in a Two-sector Kaleckian Model

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    This study extends a two-sector Kaleckian model of growth and income distribution by incorporating the dynamics of labour productivity growth. The economy is composed of investment goods and consumption goods producing sectors, with the sectoral demand and productivity growth interaction dynamically formalized. The study analyses the conditions for the cyclical demand and productivity growth phenomena in a two-sector economy. The model reveals that each sector may present a different response in capacity utilization rate to a change in sectoral income distribution. These phenomena are specific to two-sector models, and cannot be observed with a conventional aggregate growth model

    Income distribution, technical change, and economic growth: A two-sector Kalecki--Kaldor approach

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    This paper presents a two-sector Kalecki--Kaldor model of income distribution, technical change, and economic growth. The model is Kaleckian in the sense that it incorporates mark-up pricing, investment independent of saving, and excess capacity. It is also Kaldorian in that labour productivity growth is led by Kaldor's technical progress function. In other words, productivity growth is endogenously realised through the technology embodied in new capital stock, which differentiates our model from previous two-sector models. Our extension drastically changes the standard Kaleckian implications. We find that although the economic activity levels in the short run are led by the demand and income distribution parameters, economic growth in the long run is realised by supply-side (i.e. technical change and the associated productivity and wage growth) parameters. The important implication of our findings is that a two-sector economy faces a trade-off between a high economic growth rate and the local stability of the steady state

    First record of Euborlasia nigrocincta Coe, 1940 (Nemertea: Heteronemertea) from the western Pacific

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    The heteronemertean Euborlasia nigrocincta Coe, 1940 was previously known exclusively from the eastern Pacific. A specimen collected on the Izu Peninsula, Honshu, Japan, herein identified as E. nigrocincta, represents the first record of the species from the western Pacific, increasing the western extent of the species’ known range by more than 8300 km and indicating an amphi-Pacific distributio

    Pacific Equatorial Age Transect : expeditions 320 and 321 of the riserless drilling platform from and to Honolulu, Hawaii (USA), Sites U1331–U1336, 5 March–4 May 2009 and Honolulu, Hawaii (USA), to San Diego, California (USA), Sites U1337–U1338, 4 May–22 June 2009

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    Integrated Ocean Drilling Program Expedition 320/321, "Pacific Equatorial Age Transect" (Sites U1331–U1338), was designed to recover a continuous Cenozoic record of the equatorial Pacific by coring above the paleoposition of the Equator at successive crustal ages on the Pacific plate. These sediments record the evolution of the equatorial climate system throughout the Cenozoic. As we gained more information about the past movement of plates and when in Earth's history "critical" climate events took place, it became possible to drill an age transect ("flow-line") along the position of the paleoequator in the Pacific, targeting important time slices where the sedimentary archive allows us to reconstruct past climatic and tectonic conditions. The Pacific Equatorial Age Transect (PEAT) program cored eight sites from the sediment surface to basement, with basalt aged between 53 and 18 Ma, covering the time period following maximum Cenozoic warmth, through initial major glaciations, to today. The PEAT program allows the reconstruction of extreme changes of the calcium carbonate compensation depth (CCD) across major geological boundaries during the last 53 m.y. A very shallow CCD during most of the Paleogene makes it difficult to obtain well-preserved carbonate sediments during these stratigraphic intervals, but Expedition 320 recovered a unique sedimentary biogenic sediment archive for time periods just after the Paleocene/Eocene boundary event, the Eocene cooling, the Eocene–Oligocene transition, the "one cold pole" Oligocene, the Oligocene–Miocene transition, and the middle Miocene cooling. Expedition 321, the second part of the PEAT program, recovered sediments from the time period roughly from 25 Ma forward, including sediments crossing the Oligocene/Miocene boundary and two major Neogene equatorial Pacific sediment sections. Together with older Deep Sea Drilling Project and Ocean Drilling Program drilling in the equatorial Pacific, we can delineate the position of the paleoequator and variations in sediment thickness from ~150°W to 110°W longitude
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