Identification of Shallow Submarine Hydrothermal Activity Using Multispectral Satellite Images

Abstract

Processing of multispectral images allows identification of areas with shallow submarine hydrothermal activity. Temperature data over time were processed based on data from MODIS (Moderate-resolution Imaging Spectro-radiometer) images of the Punta Mita area in Mexico, where active hydrothermal vents discharge thermal water at a temperature of 85°C at a 10 m depth. This was done to demonstrate that detectable temperature anomalies on the ocean surface are related to the presence of hydrothermal shallow vents on the sea floor. Results showed that temperature anomalies due to the discharge of hydrothermal fluids at shallow depths are large enough to be observed by satellites. The temperature of the area where submarine vents are located is consistently higher than the surrounding area by at least 1°C. The analysis was performed based on data for 288 days, including daily and seasonal variations that do not mask the temperature anomaly.