Study of catastrophic gas blowout zones in the Arctic based on passive microseismic monitoring (on the example of Lake Otkrytiye)

Abstract

For the first time, the technology of 4D passive microseismic monitoring (MSM) was used to study powerful gas blowout from the Earth's cryolithosphere in the Arctic. In the region of the deep thermokarst Lake Otkrytiye (Discovery), an active strong subvertical gas-hydrodynamic zone was revealed by MSM 4D. Based on the patterns of microseismic events distribution, the migration of formation fluids (primarily gas) was proved from the Cenomanian water-gas-saturated deposits of the Upper Cretaceous with powerful gas eruptions from the bottom of Lake Otkrytiye resulting in the formation of giant craters with a diameter of up to 30-40 m. The MSM 4D method contributes to solving the challenges of preventing and eliminating emergencies of a natural and man-made nature, and therefore belongs to the category of critical technologies.

New Catastrophic Gas Blowout and Giant Crater on the Yamal Peninsula in 2020: Results of the Expedition and Data Processing

“…During the period 2014-2020, in the north of Western Siberia, specialists from the Oil and Gas Research Institute of Russian Academy of Sciences (OGRI RAS) [6,8,[21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] carried out comprehensive studies of the onshore and offshore degassing processes (lakes, rivers), including the distribution of thermokarst lakes, at the bottom of which direct signs of degassing were revealed in the form of numerous crater-like objects-pockmarks [69]. A wide complex of geological-geophysical methods and equipment was used in field surveys, including aerial photography from unmanned aerial vehicles (UAVs) [8,[29][30][31][32][33][34][35][36][37][38]. As a result of 13 field expeditions and on the basis of the interpretation of ultra-high resolution RS data of the Earth from space, the authors from the OGRI RAS for the first time revealed 1860 zones of active degassing with the formation of craters of gas emissions at the bottom of 1667 thermokarst lakes, four rivers and two bays on the Yamal Peninsula [31][32][33][34][35][36].…”

“…A wide complex of geological-geophysical methods and equipment was used in field surveys, including aerial photography from unmanned aerial vehicles (UAVs) [8,[29][30][31][32][33][34][35][36][37][38]. As a result of 13 field expeditions and on the basis of the interpretation of ultra-high resolution RS data of the Earth from space, the authors from the OGRI RAS for the first time revealed 1860 zones of active degassing with the formation of craters of gas emissions at the bottom of 1667 thermokarst lakes, four rivers and two bays on the Yamal Peninsula [31][32][33][34][35][36]. In addition, a regional connection was established between the identified degassing zones and the areas of increased methane concentration in the atmosphere, recorded by the TROPOspheric Monitoring Instrument (TROPOMI) spectrometer on European Space Agency (ESA) Sentinel-5p satellite [34].…”

“…In addition, a regional connection was established between the identified degassing zones and the areas of increased methane concentration in the atmosphere, recorded by the TROPOspheric Monitoring Instrument (TROPOMI) spectrometer on European Space Agency (ESA) Sentinel-5p satellite [34]. All received data were loaded into the created and constantly developed OGRI RAS geoinformation system "Arctic and World Ocean" [6][7][8][25][26][27][28][29][30][31][32][33][34][35][36][37].…”

“…The first such crater-like object was discovered in the central part of the Yamal Peninsula in the summer of 2014 by helicopter pilots, 30 km to the south of the unique Bovanenkovo oil and gas condensate field, the development of which began in 2012 by PJSC Gazprom [6]. The inner and outer dimensions of the crater exceeded 26 and 40 m, respectively, and the depth was about 50 m. This crater was widely known as the Yamal Crater, and the authors assigned it the C1 index in the Arctic and World Ocean geoinformation system [6][7][8][25][26][27][28][29][30][31][32][33][34][35][36][37]. Soon, in the north of Western Siberia, several more similar craters were discovered, to which the authors assigned the indices C2, C3, C4, etc.…”

“…Studies carried out by the authors during the period 2014-2020 have shown a great potential hazard of the Earth degassing in the regions where the cryolithosphere is spread [6][7][8][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]. The C1 crater was formed at only 3.5 km from the Bovanenkovo-Ukhta main high-pressure gas pipeline, and the C9 crater was formed near the railway.…”