Evidence from Rb–Sr mineral ages for multiple orogenic events in the Caledonides of Shetland, Scotland

Shetland occupies a unique central location within the North Atlantic Caledonides. Thirty-three new high-precision Rb–Sr mineral ages indicate a polyorogenic history. Ages of 723–702 Ma obtained from the vicinity of the Wester Keolka Shear Zone indicate a Neoproterozoic (Knoydartian) age and preclude its correlation with the Silurian Moine Thrust. Ordovician ages of c. 480–443 Ma obtained from the Yell Sound Group and the East Mainland Succession constrain deformation fabrics and metamorphic assemblages to have formed during Grampian accretionary orogenic events, broadly contemporaneously with orogenesis of the Dalradian Supergroup in Ireland and mainland Scotland. The relative paucity of Silurian ages is attributed to a likely location at a high structural level in the Scandian nappe pile relative to mainland Scotland. Ages of c. 416 and c. 411 Ma for the Uyea Shear Zone suggest a late orogenic evolution that has more in common with East Greenland and Norway than with northern mainland Scotland

Regional Disparities in Per Capita Income in India: Convergence or Divergence?

The paper looks at the latest evidence of what has been happening to regional disparities in per capita income (measured as Gross State Domestic Product per capita) in India over the first decade of the twenty first century (1999/00 to 2010/11) by estimating cross section equations for unconditional and conditional beta convergence and sigma convergence across thirty two regions (twenty-eight States and four Union Territories). There is no evidence of unconditional convergence, but weak evidence of conditional convergence controlling for population growth; credit growth; male literacy; the share of agriculture in State GDP, and State expenditure as a share of State GDP. Sigma divergence has increased continuously, except among the poorest States

The Endogeneity of the Natural Rate of Growth

The aim of this paper is to estimate the sensitivity of the natural rate of growth to the actual rate of growth for 15 OECD countries over the period 1961 to 1995, on the hypothesis that the natural rate of growth is not exogenously given. To do this we estimate the natural rate of growth and, then, how it changes when the actual growth rate is different from the natural rate. As a side test of the endogeneity hypothesis, we also test for the direction of causality between national output and factor inputs for the same set of countries. Our results support the idea that the natural rate of growth is responsive to the actual rate of growth and bring to the fore the importance of focusing on demand as well as supply for an understanding of growth rate differences between countries

Trade liberalisation, the balance of payments and growth in Latin America

The broad purpose of trade liberalisation is to raise the rate of growth of countries on a sustainable basis, consistent with the achievement of other macroeconomic objectives. In this paper we consider whether trade liberalisation in seventeen countries of Latin America has improved the trade-off between GDP growth and the trade balance, allowing the countries to grow faster without sacrificing foreign exchange. We find that in the aftermath of liberalisation, the majority of countries did grow faster, but at the expense of a deteriorating trade balance. Testing formally for the impact of trade liberalisation in a full model of trade balance determination, we find that only in Chile and Venezuela has the trade-off unequivocally improved. In other countries there has been a significant deterioration or no change. Nine out of the seventeen countries have grown faster post-liberalisation than pre-liberalisation but, except for Chile and Venezuela, at the expense of a wider trade or current account deficit

Has trade liberalisation in poor countries delivered the promises expected?

The paper reviews the evidence of the impact of trade liberalisation on the economic performance of poor developing countries with respect to poverty reduction, the distribution of income within countries, the distribution of income between countries, trade and the balance of payments, and economic growth, and finds that liberalisation has not delivered the benefits expected. Economic theory, and the historical and contemporary evidence, all provide arguments for protection of industrial activities in developing countries

Explaining Differences in the Productivity of Capital Across Countries in the Context of 'New' Growth Theory

The purpose of this paper is to explain differences in the productivity of capital across countries taking 84 rich and poor countries over the period 1980-2011, and to test the orthodox neoclassical assumption of diminishing returns to capital. The marginal product of capital is measured as the ratio of the long-run growth of GDP to a countrys investment ratio. Twenty potential determinants are considered using a general-to-specific model selection procedure. Education, government consumption, geography, export growth, openness, political rights and macroeconomic instability turn out to be the most important variables. The data also suggest constant returns to capital, so investment matters for long-run growth

Trace element geochemistry of peridotites from the Izu-Bonin-Mariana Forearc, Leg 125

Trace element analyses (first-series transition elements, Ti, Rb, Sr, Zr, Y, Nb, and REE) were carried out on whole rocks and minerals from 10 peridotite samples from both Conical Seamount in the Mariana forearc and Torishima Forearc Seamount in the Izu-Bonin forearc using a combination of XRF, ID-MS, ICP-MS, and ion microprobe. The concentrations of incompatible trace elements are generally low, reflecting the highly residual nature of the peridotites and their low clinopyroxene content (n ratios in the range of 0.05-0.25; several samples show possible small positive Eu anomalies. LREE enrichment is common to both seamounts, although the peridotites from Conical Seamount have higher (La/Ce)n ratios on extended chondrite-normalized plots, in which both REEs and other trace elements are organized according to their incompatibility with respect to a harzburgitic mantle. Comparison with abyssal peridotite patterns suggests that the LREEs, Rb, Nb, Sr, Sm, and Eu are all enriched in the Leg 125 peridotites, but Ti and the HREEs exhibit no obvious enrichment. The peridotites also give positive anomalies for Zr and Sr relative to their neighboring REEs. Covariation diagrams based on clinopyroxene data show that Ti and the HREEs plot on an extension of an abyssal peridotite trend to more residual compositions. However, the LREEs, Rb, Sr, Sm, and Eu are displaced off this trend toward higher values, suggesting that these elements were introduced during an enrichment event. The axis of dispersion on these plots further suggests that enrichment took place during or after melting and thus was not a characteristic of the lithosphere before subduction. Compared with boninites sampled from the Izu-Bonin-Mariana forearc, the peridotites are significantly more enriched in LREEs. Modeling of the melting process indicates that if they represent the most depleted residues of the melting events that generated forearc boninites they must have experienced subsolidus enrichment in these elements, as well as in Rb, Sr, Zr, Nb, Sm, and Eu. The lack of any correlation with the degree of serpentinization suggests that low-temperature fluids were not the prime cause of enrichment. The enrichment in the high-field-strength elements also suggests that at least some of this enrichment may have involved melts rather than aqueous fluids. Moreover, the presence of the hydrous minerals magnesio-hornblende and tremolite and the common resorption of orthopyroxene indicate that this high-temperature peridotite-fluid interaction may have taken place in a water-rich environment in the forearc following the melting event that produced the boninites. The peridotites from Leg 125 may therefore contain a record of an important flux of elements into the mantle wedge during the initial formation of forearc lithosphere. Ophiolitic peridotites with these characteristics have not yet been reported, perhaps because the precise equivalents to the serpentinite seamounts have not been analyzed

Gazelle seasonal mobility in the Jordanian steppe: The use of dental isotopes and microwear as environmental markers, applied to Epipalaeolithic Kharaneh IV

The Early/Middle Epipalaeolithic aggregation site of Kharaneh IV in the east Jordan steppe is one of the largest of the period, showing repeated use, high degrees of site investment, and relatively prolonged periods of occupation. Hunters relied heavily on the single prey species, Gazella subgutturosa. This paper reports on isotopic analyses of gazelle teeth, drawn from the Kharaneh IV assemblage, to explore the seasonal and spatial distribution of gazelle in life and examine models of long-distance seasonal gazelle migrations. Dental microwear analysis is also employed to assess hunting seasons. Results from sequential isotope analyses of 11 Epipalaeolithic gazelle molars show that, with one exception, gazelle did not move seasonally from the limestone steppe onto other geologies, nor did they seasonally relocate to areas with different climate regimes. Rather, seasonal herd mobility seems to have been local, meaning animals would have been available in the vicinity of Kharaneh IV year-round. Results from 19 microwear analyses show some gazelle to have died in spring when grass graze was available, whilst others had been browsing around their time of death, indicating non-spring hunting. Microwear evidence thus suggests gazelle were hunted in more than one restricted season. The implications of these new datasets for hunter-gatherer use of the steppe, and potential hunting methods, is highlighted

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

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