Statistical methods for describing seafloor topography

• Published in: Geophysical research letters Vol. 14; no. 10; pp. 1061 - 1064
• Main Authors: Shaw, Peter R., Smith, Deborah K.
• Format: Journal Article
• Language: English
• Published: Blackwell Publishing Ltd 01.10.1987
• Subjects: Histograms; Marine; Roughness; Samples; Sea beds; Slopes; Statistical methods; Topography; Variance
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/GL014i010p01061

We present a method for objectively characterizing a swath of digitally sampled seafloor topography. Our method analyzes the distribution of surface slopes by compiling surface‐normal vectors into a two‐dimensional histogram using an equal‐area projection. The direction of maximum variance (first principal axis) of the histogram is used to determine the azimuth of lineations in the topography, and the variance is used as a measure of seafloor roughness. We apply the method to short sections of Sea Beam swath data and find that the histogram parameters are effective in describing the behavior of the topography. In particular, similar patterns are observed for a sequence of histograms derived from data collected over the Mendocino and the Surveyor fracture zones in the northeast Pacific. Because the method does not require any data modification and is suitable for irregularly‐shaped sample regions, it lends itself to real‐time analysis.