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Garmany, J, Orcutt JA, Parker RL.  1979.  Travel time inversion: A geometrical approach. Journal of Geophysical Research. 84:3615-3622.   10.1029/JB084iB07p03615   AbstractWebsite

A geometric formulation of the seismic travel time problem is given based upon the use of slowness as an independent variable. Many of the difficulties in the conventional treatment (e.g., singular kernels) are thereby, avoided. Furthermore, it is shown that the inverse problem possesses an inherently linear formulation. In this formalism we are able to provide extremal solutions giving upper and lower depth bounds using linear programing. This approach has been compared with two well-known nonlinear extremal inversions. We find our technique to be easier to implement and find that it often generates superior results.

Gee, JS, Cande SC, Hildebrand JA, Donnelly K, Parker RL.  2000.  Geomagnetic intensity variations over the past 780 kyr obtained from near-seafloor magnetic anomalies. Nature. 408:827-832.   10.1038/35048513   AbstractWebsite

Knowledge of past variations in the intensity of the Earth's magnetic field provides an important constraint on models of the geodynamo. A record of absolute palaeointensity for the past 50 kyr has been compiled from archaeomagnetic and volcanic materials, and relative palaeointensities over the past 800 kyr have been obtained from sedimentary sequences. But a long-term record of geomagnetic intensity should also be carried by the thermoremanence of the oceanic crust. Here we show that near-seafloor magnetic anomalies recorded over the southern East Pacific Rise are well correlated with independent estimates of geomagnetic intensity during the past 780 kyr. Moreover, the pattern of absolute palaeointensity of seafloor glass samples from the same area agrees with the well-documented dipole intensity pattern for the past 50 kyr. A comparison of palaeointensities derived from seafloor glass samples with global intensity variations thus allows us to estimate the ages of surficial lava flows in this region. The record of geomagnetic intensity preserved in the oceanic crust should provide a higher-time-resolution record of crustal accretion processes at mid-ocean ridges than has previously been obtainable.

Gill, AE, Parker RL.  1970.  Contours of “h cosec θ” for the world's oceans. Deep-Sea Research. 17:823-&.   10.1016/0011-7471(70)90044-6   AbstractWebsite

Contours of d = h cosec θ are presented for the worlds oceans, where h is the depth of the ocean and θ the latitude. This quantity is the distance between the ocean surface and the ocean floor in the direction of the axis of rotation of the earth. The inverse is proportional to 2Ω/d = f/h where Ω is the rate of rotation of the earth and f = 2Ω sinθ is the Coriolis parameter. The quantity f/h may be interpreted as the potential vorticity of the ocean in the absence of motion relative to the rotating earth.

Greenhouse, JP, Parker RL, White A.  1973.  Modelling geomagnetic variations in or near an ocean using a generalized image technique. Geophysical Journal of the Royal Astronomical Society. 32:325-338.   10.1111/j.1365-246X.1973.tb05834.x   AbstractWebsite

A generalized image technique is described for modelling electromagnetic induction in two-dimensional systems, consisting of a thin (Price-type) ocean overlying a perfect conductor in the mantle. The method constructs a Green's function for currents in the ocean by conformally mapping the perfect conductor boundary into a straight line. Examples are given that show the effects to be expected at an ocean-continent boundary with isotherms rising under the ocean, and at a mid-ocean rise where the high temperatures are believed to be quite shallow.