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Gallagher, J, Orcutt J, Simpson P, Wright D, Pearlman J, Raymond L.  2015.  Facilitating open exchange of data and information. Earth Science Informatics. 8:721-739.   10.1007/s12145-014-0202-2   AbstractWebsite

By broad consensus, Open Data presents great value. However, beyond that simple statement, there are a number of complex, and sometimes contentious, issues that the science community must address. In this review, we examine the current state of the core issues of Open Data with the unique perspective and use cases of the ocean science community: interoperability; discovery and access; quality and fitness for purpose; and sustainability. The topics of Governance and Data Publication are also examined in detail. Each of the areas covered are, by themselves, complex and the approaches to the issues under consideration are often at odds with each other. Any comprehensive policy on Open Data will require compromises that are best resolved by broad community input. In the final section of the review, we provide recommendations that serve as a starting point for these discussions.

Burnett, MS, Orcutt JA, Olson AH.  1988.  A Finite-Element Computation of Seismic Diffraction About the Rise Axis Magma Chamber. Geophysical Research Letters. 15:1487-1490.   10.1029/GL015i013p01487   AbstractWebsite

In a previous study, models of the crust and magma chamber at 12°50′N on the East Pacific Rise were derived with a two-dimensional ray-tracing analysis of rise-normal refraction lines. The best model featured a 4 km wide axial magma chamber, but the data contained diffraction effects that were not modeled by geometric ray theory. This raised questions as to whether this model would reproduce the waveform data and whether diffraction might be obscuring a much larger magma chamber. We have tested the model with a finite element calculation of synthetic seismograms. This method incorporates full wave effects, including diffraction. The synthetics accurately reproduce the data and exhibit diffraction phenomena similar to those in the data. The previous travel time analysis was largely successful and was only slightly compromised by diffraction. Diffraction in rise-normal refraction experiments is, therefore, not obscuring a large, low velocity magma chamber.

Laske, G, Morgan JP, Orcutt JA.  1999.  First results from the Hawaiian SWELL pilot experiment. Geophysical Research Letters. 26:3397-3400.   10.1029/1999gl005401   AbstractWebsite

In a year-long pilot experiment to the southwest of the Hawaiian Islands, we recorded teleseismic intermediate-period Rayleigh waves on ocean-bottom "L-CHEAPO" instruments using differential pressure gauges as sensors. We analyzed over 70 events and obtained accurate phase velocity estimates at periods between 15 and 70s. The average seismic structure beneath the pilot array does not deviate significantly from a standard seismic model of 100 Myr old oceanic lithosphere. However, we find strong lateral velocity variations across the array with large negative anomalies appearing within roughly 300km of the island chain. We are able to image the edge of the Hawaiian Swell and hence demonstrate the importance of making phase velocity measurements on the ocean floor.

Herzfeld, UC, Kim II, Orcutt JA, Fox CG.  1993.  Fractal Geometry and Sea-Floor Topography - Theoretical Concepts Versus Data-Analysis for the Juan-De-Fuca Ridge and the East Pacific Rise. Annales Geophysicae-Atmospheres Hydrospheres and Space Sciences. 11:532-541. AbstractWebsite

It has recently become a matter of discussion among geologists and geophysicists whether the topographic structure of the seafloor can be described as a fractal process, using the concepts of self-similarity and self-affinity. The objective of this study is to compare the implications of these concepts with observations of the seafloor. The analyses are based on multibeam sonar bathymetric data from two areas in the Pacific Ocean: the East Pacific Rise at 13-degrees-N/104-degrees-W and the Juan de Fuca Ridge at 44.8-degrees-N/130-degrees-W Using methods from geostatistics - the theory of regionalized variables - the bathymetric data are considered a stochastic process satisfying the intrinsic hypothesis. The essential step in the analysis is the application of a variogram criterion to test for self-similarity and self-affinity. Variograms are calculated for a range of scales to analyse the spatial continuity of the process depending on resolution. This leads to the following results: (1) The seafloor is not self-similar nor self-affine. Instead, scale-dependent spatial structures are observed, which may be related to scale-specific geologic processes; (2) According to the definition of a fractal as an object of Hausdorff dimension strictly exceeding its topological dimension, the seafloor may be a fractal. However, at small scales the seafloor is smoother than mean-square differentiable; (3) Possible scaling behaviour would call for a more complex concept than self-similarity or self-affinity based on the sequence of scale-dependent models; (4) According to model parameters that are specific for each area, slow and fast spreading oceanic ridges can be distinguished. The variogram criterion provides an easy-to-use tool to test whether any studied geophysical field, and more generally, any spatially defined process, is indeed scaling.

Orcutt, JA, Brink K.  1993.  The future of basic ocean science research in the Department of the Navy. EOS Trans. AGU. 74:219. Abstract
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