The Bauer scarp ridge jump: a complex tectonic sequence revealed in satellite altimetry

We investigate here the ridge jump that led to abandonment of the Galapagos Rise and formation of the Batter scarp during the initiation of the present day configuration of the East Pacific Rise since the lower Miocene. We use recently available high-resolution satellite-derived gravity data to investigate in detail the tectonic structure of the eastern Pacific from the Equator to 20%. With this data, we identify fracture zones, abandoned spreading ridges, scarps, and other seafloor features that provide evidence for discerning tectonic history. Based on our structural interpretation of the satellite-derived gravity field, we make the following conclusions: (1) The Galapagos Rise spreading center appears to have originated by opening of the Marquesas/Mendana transform complex as a result of the change in spreading direction following breakup of the Farallon Plate. (2) The Galapagos Rise was not the sole locus of spreading following plate reorganization at ~ 20 Ma through to the initiation of the Bauer scarp at ~ 8 Ma, as had been previously hypothesized. Rather, it and a second western spreading axis were likely active concurrently, forming a counterclockwise-rotating Bauer Microplate at a much earlier stage than thought previously. (3) The Bauer scarps are pseudofaults associated with northward rift propagation. Propagation proceeded in several stages. A first propagator emanating from the Garrett transform complex stalled at the future location of the Wilkes transform creating an area of complex morphology near its northern tip. A second propagator, also emanating from the Garrett complex followed in the first’s wake and broke through the complex region. At this point the propagation proceeded very rapidly to the northern end of the Bauer Microplate (the Gallego fracture zone, later to become the Yaquina transform fault). Ridge propagation continued north in two more stages, creating the Gofar and Quebrada transforms at the terminus of each stage

Kepler-18b,c, and d: A System of Three Planets Confirmed by Transit Timing Variations, Light Curve Validation, Warm-Spitzer Photometry, and Radial Velocity Measurements

We report the detection of three transiting planets around a Sun-like star, which we designate Kepler-18. The transit signals were detected in photometric data from the Kepler satellite, and were confirmed to arise from planets using a combination of large transit-timing variations (TTVs), radial velocity variations, Warm-Spitzer observations, and statistical analysis of false-positive probabilities. The Kepler-18 star has a mass of 0.97 M_☉, a radius of 1.1 R_☉, an effective temperature of 5345 K, and an iron abundance of [Fe/H] = +0.19. The planets have orbital periods of approximately 3.5, 7.6, and 14.9 days. The innermost planet "b" is a "super-Earth" with a mass of 6.9 ± 3.4 M_⊕, a radius of 2.00 ± 0.10 R_⊕, and a mean density of 4.9 ± 2.4 g cm^3. The two outer planets "c" and "d" are both low-density Neptune-mass planets. Kepler-18c has a mass of 17.3 ± 1.9 M_⊕, a radius of 5.49 ± 0.26 R_⊕, and a mean density of 0.59 ± 0.07 g cm^3, while Kepler-18d has a mass of 16.4 ± 1.4 M_⊕, a radius of 6.98 ± 0.33 R_⊕ and a mean density of 0.27 ± 0.03 g cm^3. Kepler-18c and Kepler-18d have orbital periods near a 2:1 mean-motion resonance, leading to large and readily detected TTVs

The Development of the Blackfoot Clinical Rating Scale for Evaluating and Recording Personality Changes in Mentally Ill Patients

The problem discussed in this thesis is the conception, development, and application of the Blackfoot Clinical Rating Scale, together with methods employed in establishing reliability and validity

Abyssal Hill Segmentation: Quantitative Analysis of the East Pacific Rise Flanks 7°S-9°S

The recent RN Maurice Ewing EW9105 Hydrosweep survey of the East Pacific Rise (EPR) and adjacent flanks between 7°S and 9°S provides an excellent opportunity to explore the causal relationship between the ridge and the abyssal hills which form on its flanks. These data cover 100% of the flanking abyssal hills to 115 km on either side of the axis. We apply the methodology of Goff and Jordan (1988) for estimating statistical characteristics of abyssal hill morphology (rms height, characteristic lengths and widths, plan view aspect ratio, azimuthal orientation, and fractal dimension). Principal observations include the following: (I) the rms height of abyssal hill morphology is negatively correlated with the width of the 5- to 20-km-wide crestal high, consistent with the observations of Goff (1991) for northern EPR abyssal hill morphology; (2) the characteristic abyssal hill width displays no systematic variation with position relative to ridge segmentation within the EW9105 survey area, in contrast with observations of Goff (1991) for northern EPR abyssal hill morphology in which characteristic widths tend to be smallest al segment ends and largest toward the middle of segments; (3) abyssal hill rms heights and characteristic widths are very large just north of a counterclockwise rotating "nannoplate", suggesting that the overlap region is being pushed northward in response to microplate-style tectonics; and (4) within the 7°12'S-8°38'S segment, abyssal hill lineaments are generally parallel to the ridge axis, while south of this area, abyssal hill lineaments rotate with a larger "radius of curvature" than does the EPR axis approaching the EPR-Wilkes ridge-transform intersection

The control of gullies

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The appraisal of farm buildings

Caption title.Digitized 2006 AES MoU

The relation of electricity to Missouri agriculture

Cover title.Digitized 2006 AES MoU

Morphology of a 'Superfast' Mid-Ocean Ridge Crest and Flanks: The East Pacific Rise, 7°- 9° S

Detailed bathymetric data from a Hydrosweep multibeam sonar survey of a 250 km-long portion of the 'superfast'- spreading southern East Pacific Rise crest and flanks show that the along-axis variation in morphology and axial depth differs significantly from that observed at the fast-spreading northern East Pacific Rise. While the deep mantle upwelling pattern is similar under the northern and southern East Pacific Rise, our observations require that the connectivity of the shallow, subcrestal plumbing system be more efficient beneath the 'super-fast' spreading southern East Pacific Rise than beneath the slower spreading northern East Pacific Rise

The Missouri soil saving dam : low-cost structure for use in farm plans for water management

Cover title."A revision of Bulletin 434" -- P. [3]

The Missouri soil saving dam : low-cost structure for use in farm plans for water management

Cover title