Global topographic data and the assumption of Airy isostasy have been used to estimate the crustal volumes of the continents and the oceanic and continental submarine plateaus. The calculated crustal volumes are 7182 X lo6 km3 for the continents, 242 x lo6 km3 for continental submarine plateaus, and 369 X lo6 km3 for oceanic plateaus. The Falkland Plateau and the Lord Howe Rise are the two larg...

Large-scale, lateral fluid flow through oceanic crust provides an explanation for regionally low heat flow in several seafloor settings. A well-mixed aquifer (WMA) model provides a quantitative and conceptual tool for explaining anomalously low heat flow based on an analytical representation of fluid and heat flow, assuming lateral fluid flow in basement in a layer directly below the ocean sedi...

This paper looks at the challenges confronting plate tectonics— the ruling paradigm in the earth sciences. The classical model of thin lithospheric plates moving over a global asthenosphere is shown to be implausible. Evidence is presented that appears to contradict continental drift, seafloor spreading, and subduction, as well as the claim that the oceanic crust is relatively young. The proble...

The chemical differences between deep- and shallow-mantle sources of oceanic basalts provide evidence that several distinct components coexist within the Earth's mantle. Most of these components have been identified as recycled in origin. However, the noble-gas signature is still a matter of debate and questions the preservation of primitive regions in the convective mantle. We show that a mode...

The subaerial surface of Koolau volcano is composed of lavas that define the distinctive endmember composition for Hawaiian shield lavas, known as the Koolau component, now designated as the Makapuustage. The geochemical characteristics of lavas recovered by the Koolau Scientific Drilling Project (KSDP) show that this distinctive composition forms a <300-m thick veneer. Below this veneer, from ...

Understanding how the Earth’s first continental land masses were generated is important because the processes responsible directly affected the evolution of the planet’s primordial silicate interior, and also its atmosphere and hydrosphere. Archaean continental crust is dominated by rocks of the trondhjemite–tonalite–granodiorite (TTG) suite. These can be divided into (1) a midto late Archaean ...

[1] Seismic studies of the deep mantle suffer from the fact that the probing seismic waves must traverse the highly heterogeneous and poorly resolved shallow structure. One potential way forward is to develop highresolution models of the crust and upper mantle using other information. Here we describe the construction of a geodynamic a priori model of some aspects of upper mantle seismic veloci...

10 Volcanogenic Massive Sulphide (VMS) deposits are commonly enriched in Cu, Zn and 11 Pb and can also be variably enriched in Au, As, Sb, Se and Te. The behaviour of these elements 12 during hydrothermal alteration of the oceanic crust is not well known. Ocean Drilling Program 13 (ODP) Hole 1256D penetrates a complete in-situ section of the upper oceanic crust providing a 14 unique sample suit...

Much of my research career has been spent working both on modern oceanic volcanic systems and at the same time looking at their Archaean counterparts. Many authors have attempted to make inferences on early Earth models based on modern processes which can be increasingly well constrained. In this short review I show how we are beginning to understand and quantify inputs to modern subduction sys...