Detection of diffuse seafloor venting using a structured light laser sensor: 2. Evaluation of detection sensitivity and limitations

Abstract

Algorithms to detect diffuse hydrothermal vent fluids using the structured light laser sensor have proven to be successful. However, potential limitations due to survey parameters, including altitude and vehicle heading, have not been explored and are the focus of this study. Data from 12 surveys conducted over a single hydrothermal vent at three different altitudes (2.7 m, 4.2 m, and 6.2 m) and four different headings are analyzed. Increasing survey altitude decreases the resolution and intensity of the imaged laser line; therefore, range‐dependent processing considerations to maintain detection sensitivity are presented. Analysis of these surveys suggests minimal degradation of vent detection capabilities from survey altitudes up to 6 m. Additionally, as the shape and location of the detected distortion patterns vary with survey heading and altitude they are presented as potential indications of plume shape and rise height. The effects of range and survey heading are important for future applications of this sensor which may include surveying from higher, faster flying autonomous underwater vehicles.