Faculty of Physics
M.V.Lomonosov Moscow State University
Regular Article

# Measurement of fluid methane discharge in Laspi Bay by trap method

## T. V. Malakhova$^1$, A. A. Budnikov$^2$, I. N. Ivanova$^2$, A. I. Murashova$^1$

### Moscow University Physics Bulletin 2020. N 6.

• Article
Annotation

The measurements of methane fluid flow from bottom sediments and daily monitoring of the main hydrophysical parameters near the seepage site in Laspi Bay were carried out. The values of fluid flows varied by an order of magnitude (1.4 - 74.3 mmol / m2 day) at points separated by a distance of not more than 10 m. It is assumed that denser carbonate deposits at the seepage site can localize gas flows, reducing the volume of fluid discharge. It was shown that the specific fluid discharge in Laspi Bay is comparable to the gas flow from single seep, the maximum fluid flow is only 3.5 times lower compared to the minimum flow recorded from the gas bubbles emission point. The change in hydrological parameters above the gas bubble discharge area is significantly affected by the weather conditions. Salinity сhanges during the measurements amounted to a limit value of 0.08 ‰, which indicates the absence of a high-yield freshwater submarine discharge, which is often associated withseepages. Episodes of abrupt decrease of oxygen content with amplitude 0.5 mg/l at night hours, not associated with changes in water temperature and weather conditions, can be caused by hydrogen sulfide inflow in bubble and fluid gases.

Approved: 2021 March 23
PACS:
92.05.Hj Physical and chemical properties of seawater
92.10.Lq Turbulence, diffusion, and mixing processes in oceanography
92.60.Cc Ocean/atmosphere interactions, air/sea constituent fluxes
Rissian citation:
Т. В. Малахова, А. А. Будников, И. Н. Иванова, А. И. Мурашова.
Вестн. Моск. ун-та. Сер. 3. Физ. Астрон. 2020. № 6. С. 162.
Authors
T. V. Malakhova$^1$, A. A. Budnikov$^2$, I. N. Ivanova$^2$, A. I. Murashova$^1$
$^1$A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS
$^2$Faculty of physics, M.V. Lomonosov Moscow State University

### Science News of the Faculty of Physics, Lomonosov Moscow State University

This new information publication, which is intended to convey to the staff, students and graduate students, faculty colleagues and partners of the main achievements of scientists and scientific information on the events in the life of university physicists.