GEOLOGY AND GEOPHYSICS: SCALE AND FILTER SIZE

The continental crust and lithospheric mantle are made and modified in at least 11 environments by many mechanisms. e.g. magmatic addition in oceanic arcs, stretching and underplating, shortening and imbrication, delamination, and lower crustal flow. There is a clear secular evolution from pre-plate tectonic Archean cratonic growth by inversion (3.83-3.0), through Superior-style proto-plate tectonic small arcs and blocks (3.0-2.7), the shallow UHT belts of the Proterozoic (2.7-0.6), to the modern plate tectonic world of deep UHP belts. The secular evolution of a myriad of mechanisms yields a great variety of temporal and spatial compositions and strength profiles that determine tectonic style, yet we know little of the fine-scale 4D evolution of the continental lithosphere. To improve our data base and understanding, we need highly-focused and integrated detailed mapping, structure, petrology, geochemistry, drilling, laboratory experiments and measurements, numerical and analog modeling, and intelligently-designed seismic experiments such as COCORP, BIRPS, ECORS and the Kapvaal Experiment. The field-based geological and drilling filter is very much finer than the remotely-sensed geophysical mesh. Therefore, geologic studies of the best-exposed key areas should guide geophysical studies, which, in turn, should determine drilling locations. Random data collection, whether quadrangle mapping or EARTHSCOPE, has no place in the NSF funding of basic research. Big expensive NSF programs are sidelining cheap and productive field-based geology and coarsening the filter; the correlation of scale with importance is a common fundamental error. Smaller grants and seed money should be given to more younger researchers. NSF program managers are not fatidical and should not proactively decide what is important; they should simply follow the advice of panels that review the merits of proposals submitted. There seems little scope for innovation, originality, and imagination; we are witnessing the development of shallow, enforced, conformity and need to change in ways that reduce the power and influence of the bureaucrats.