Granulometric Analysis of Shallow Vents Sediments at Banderas Bay (Mexico)

Abstract

Ocean hydrothermal activity is well known from deep-sea studies; however, few studies have been reported at shallow depth. A shallow submarine hydrothermal system at Punta Mita described in 2000 was studied to determine the grain size classification of the marine sediments of this hydrothermal system. Three sites with hydrothermal activity were included. Each one was divided into three areas: with hydrothermal activity, intermediate, and out of hydrothermal activity. In each area, two sediment cores were randomly collected by scuba diving (number of sediment cores = 18). All sediment samples were subjected to a previous treatment, to eliminate salts and organic matter. The grain sizes were sieved and then classified following the Udden–Wentworth scale. A principal coordinate analysis was performed to determine if there was any association of the statistical moments with the areas and sites of study. The textural composition of the sediments in the hydrothermal influence areas is sand, where the very fine sand is the dominant grain size, which was confirmed with the mean moment. The sediments are characteristic of the tidal areas, except for those sediments in the areas with hydrothermal activity.

Design and Analysis of Optical Window Encapsulation Structure for Laser Doppler Deep-Sea Hydrothermal Velocity Measurement System

“…Moreover, the calculated value is 91.5 MPa. p � 1.25 1.04 + 0.102506 1 + 0.00528sin 2 (ii) e pressure is released after holding for 8 hours (iii) e encapsulation structure is taken out and inspected en, the dynamic pressure experiment is carried out after the success of the hydrostatic pressure experiment: the pressure is gradually increased from 0 MPa to 91.5 MPa, and then the pressure is released. e encapsulation structure is taken out after 6 cycles of pressure and pressure relief.…”

“…Submarine hydrothermal ow rate is of great signi cance to the research on the material output ux of hydrothermal vents, the sea oor changes in sea oor geological structure, and the distribution of biological communities [1][2][3]. e deep-sea hydrothermal velocity measurement system based on the principle of laser Doppler velocity measurement is the primary measurement method to measure velocity.…”

Benthic infauna associated with a shallow-water hydrothermal system of Punta Mita (Mexico)

“…The textural composition of the sediments of S1, S2 and S3 has been reported by Rodríguez-Uribe et al . (2020), ~2 weeks apart, they collected the samples on 13 December 2017, where the very fine sand was the dominant grain size in the three sites.…”

“…2.Location of the study site. The black oval indicates the study area (modified from Rodríguez-Uribe et al ., 2020). Pictures (A), (B) and (C) illustrate the main hydrothermal vents for each study site.…”

“…The study of shallow-water hydrothermal systems can help in the understanding of various biogeochemical processes, to establish the differences between continental and submarine hydrothermal activity, in the formation of mineral deposits and the geochemical cycle of elements in the oceans (Prol-Ledesma & Canet, 2014). They are usually related to coastal volcanic activity (Tarasov et al ., 2005), but they can also be found on continental margins affected by active processes of tectonic extension (Prol-Ledesma & Canet, 2014), as is the case of Mexico, where a site is known in Punta Mita, Nayarit (Núñez-Cornú et al ., 2000; Rodríguez-Uribe et al ., 2020), and four sites on the coast of Baja California Peninsula: Punta Banda (Vidal et al ., 1978), Bahía Concepción (Prol-Ledesma et al ., 2004), Los Cabos (Prol-Ledesma et al ., 2021) and Puertecitos (Arellano-Ramirez et al ., 2017) (Figure 1).

Fig.

…”