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Abstract Earth's surface topography/bathymetry and gravity fields provide important constraints on crustal structure and the tectonic processes that act on it due, for example, to plate flexure and mantle convection. Such studies require, however, high accuracy measurements at a wide range of spatial scales. During the past few decades much progress has been made in the acquisition of bathymetry and gravity data using both shipboard and satellite altimeter methods. Surprisingly, there have been few comparisons of these data. During April–June, 2019 we had the opportunity onboard a R/VMarcus G. Langsethcruise in the northwest Pacific Ocean to compare data acquired with an EM122 Kongsberg swath bathymetry system and a refurbished Bell Aerospace BGM‐3 gravimeter with the most recent global bathymetry and gravity fields. We find that while the recovery of bathymetry and gravity from satellite radar altimeter data in areas of sparse shipboard data has been impressive, root mean square discrepancies in the range 175.5–303.4 m and 2.6–6.3 mGal exist between shipboard and satellite‐derived data. While these discrepancies are small, they are highly correlated and therefore have implications for the density structure, rock type and geological processes occurring on the deep seafloor. Shipboard data should continue to be acquired, especially over features such as seamounts, banks, and ridges that are associated with short wavelength (<25 km wavelength) bathymetric and gravimetric features beyond that is recoverable in satellite‐derived data.
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Experimental Progress Towards Testing the Behavior of Gravity at the 20-micron Distance Scale
Due to discrepancies between the Standard Model and General Relativity, questions have arisen about the fundamental behavior of gravity. Many theories have speculated that gravity behaves fundamentally different at short ranges with respect to the predictions of Newtonian theory. These discrepancies have led the Humboldt State Gravitational Research Lab to begin constructing an experiment that will test the behavior of gravity at distances that have yet to be explored. The experiment has been improved upon in many aspects and has entered an initial data acquisition phase.
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- PAR ID:
- 10343083
- Editor(s):
- Rykhus, R.; Brown, K.
- Date Published:
- Journal Name:
- Journal of undergraduate research and scholarly excellence
- Volume:
- IX
- ISSN:
- 2156-5309
- Page Range / eLocation ID:
- 23-29
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- The DOI is not currently available.
