Photo 1: Drone image of Lusi's plume and main emission during its regular geysering activity. In the background the volcanic complex of Arjuno-Welirang. The video can be viewed on YouTube by clicking . --- Photo 1: Drone image of the plume and main emission of Lusi during its regular geysering activity. In the background, the Arjuno-Welirang volcanic complex. The video can be viewed on YouTube by clicking (Ph: A. Mazzini) 
Photo 2: The central area of the Lusi crater is surrounded by an inaccessible pond 650 meters in diameter. The areas surrounding the central crater, within the 7,5 km embankment2, are characterized by small streams of hot mud with laterally extending oil slicks that can be sampled by hand (left image) and by thousands of emission points (seeps; right image). --- Photo 2: The central area of the Lusi crater is surrounded by an inaccessible pond 650 meters in diameter. The areas surrounding the central crater, within the 7.5 km2 embankment, are characterized by small streams of hot mud with laterally extended patches of oil that can be sampled by hand (image on the left) and by thousands of points of issue (seeps; right image).(Ph. A. Sciarra) The analyzes carried out on the island of Java in Indonesia have allowed to determine the largest emission of methane of a geological nature ever measured up to now
An innovative study recently published in the journal Scientific Reports di Nature, determined the amount of methane emitted by a single natural gas show, one of the largest on the planet, called Lusi, in Indonesia. The investigation, which relies on integrating ground-based data with satellite data, would suggest that some carbon-14 (radiocarbon)-based estimates of global geological methane emissions are underreported.
Geological gas emissions from petroleum sedimentary basins are a natural component of the atmospheric methane budget.
However, the global amount of geological methane released into the atmosphere is the subject of various studies, some in conflict with each other. In fact, while statistical estimates, based on fluxes measured on the ground, suggest a global emission of about 50 million tons of methane per year, other estimates, based on analyzes of radiocarbon (carbon-14) in ice cores from the 'pre-industrial era, suggest much lower values, between 0,1 and 5,4 million tons per year.
The study now published was conducted by the Center for Earth Evolution and Dynamics (CEED) of the University of Oslo (Norway) in collaboration with the National Institute of Geophysics and Volcanology (INGV), with the Netherlands Institute for Space Research in Utrecht ( SRON) and with the Indonesian agency Pusat Pengendalian Lumpur Sidoarjo (PPLS).
The researchers analyzed the spectacular methane gas emission event that developed in 2006 on the island of Java, Indonesia. The area, nicknamed Lusi, has since continued to emit water, oil, gas and mud, with eruptions capable of expelling up to 180.000 m3 of mud per day and plumes of steam reaching several tens of meters in height.
“The results we have obtained after years of monitoring”, explains Alessandra Sciarra, INGV researcher and co-author of the study, “They delve into the scientific debate about the global emission of geological methane sources and suggest that some of the recent estimates based on analyzes of ancient ice cores are significantly underestimated. In fact, the amount of methane released by Lusi already corresponds to the minimum assessment of the studies for the entire planet based on ice cores".
Lusi is a geological phenomenon fueled by high fluid pressures in sedimentary rocks and high temperatures resulting from interaction with the nearby Arjuno-Welirang volcanic complex. It is, therefore, the surface manifestation of a hybrid sedimentary-hydrothermal system. The escaping gas, rich in carbon dioxide (CO2) and methane (CH4), is ejected into the atmosphere from two central craters and from thousands of minor emission points (satellite seep) covering an area of 7,5 km2. Until now, the amount of gas actually released into the atmosphere from this site was unknown.
“Our research group has combined techniques of measurements from the ground and from a satellite, called TROPOMI, to quantify the gas released into the atmosphere by Lusi”continues Sciara. “The two techniques indicated similar methane emission values of approximately 100.000 tons per year – the highest methane emission ever measured from a single gas event”.
The results obtained by the researchers suggest that the amount of methane gas emitted by Lusi is proportionally consistent with the level of methane flux (the so-called "emission factor") typically released by other similar manifestations of terrestrial natural gas such as, for example, mud volcanoes.
This means that if the measurements from these sites were combined worldwide, the global estimates would come to indicate a geological methane emission closer to that defined with statistical criteria, based on the fluxes measured on the ground (of the order of 50 million tons of methane per year), rather than the practically negligible one based on evaluations made with radiocarbon in ice cores.
“Knowing the actual quantities and flows of methane from natural geological sources is particularly important for better assessing anthropogenic gas emissions, such as those related to the oil industry, and therefore the overall atmospheric methane balance. Finally, our study suggests that measurements of gas emissions carried out with the help of satellite data can prove to be a key tool to support ground studies and improve estimates of the global geo-methane budget”Sciara concludes.
---
INGV. The natural geological emission of methane into the atmosphere evaluated through the integrated use of a satellite and measurements on the ground
The analysis carried out on the Island of Java, Indonesia, have made it possible to determine the largest geological methane emission ever measured so far
An innovative study recently published in Nature's Scientific Reports, determined the amount of methane emitted by a single manifestation of natural gas, one of the largest on the planet, called Lusi, in Indonesia. The survey, which is based on the integration of data acquired on the ground with satellite data, would suggest that some estimates of global emissions of geological methane based on carbon-14 (radiocarbon) are underestimated.
Geological emissions of gas from sedimentary oil basins are a natural component of the atmospheric methane budget.
However, the global amount of geological methane released into the atmosphere is the subject of various studies, some at odds with each other. In fact, while the statistical estimates, based on the flows measured on the ground, suggest a global emission of about 50 million tons of methane per year, other estimates, based on analysis of radiocarbon (carbon-14) in ice cores of the pre -industrial era, suggest much lower values, between 0.1 and 5.4 million tons per year.
The study now published was conducted by the Center for Earth Evolution and Dynamics (CEED) of the University of Oslo (Norway) in collaboration with the National Institute of Geophysics and Volcanology (INGV), the Netherlands Institute for Space Research in Utrecht ( SRON) and the Indonesian agency Pusat Pengendalian Lumpur Sidoarjo (PPLS).
The researchers analyzed the spectacular manifestation of methane gas emission that developed in 2006 on the island of Java, Indonesia. The area, nicknamed Lusi, has continued to emit water, oil, gas and mud ever since, with eruptions capable of expelling up to 180,000 m3 of mud per day and plumes of steam reaching several tens of meters in height.
“The results we have obtained after years of monitoring", explains Alessandra Sciarra, researcher at INGV and co-author of the study, “deepen the scientific debate on the global emission of geological sources of methane and suggest that some of the recent estimates based on analysis of ancient ice cores are significantly underestimated. In fact, the quantity of methane released by Lusi already corresponds by itself to the minimum evaluation of the studies for the entire planet based on ice cores”.
Lusi is a geological phenomenon fueled by the high pressures of fluids in sedimentary rocks and by the high temperatures resulting from the interaction with the nearby Arjuno-Welirang volcanic complex. It is therefore the superficial manifestation of a sedimentary-hydrothermal hybrid system. The gas that escapes, rich in carbon dioxide (CO2) and methane (CH4), is expelled into the atmosphere by two central craters and by thousands of minor emission points (satellite seeps) covering an area of 7.5 km2. Until now, the amount of gas actually released into the atmosphere from this site was unknown.
“Our research group has combined measurement techniques from the ground and from a satellite, called TROPOMI, to quantify the gas released into the atmosphere by Lusi”, continuesSciarra. “The two techniques indicated similar methane emission values, of about 100,000 tons per year: this is the highest methane emission ever measured by a single manifestation of gas”.
The results obtained by the researchers suggest that the amount of methane gas emitted by Lusi is proportionally consistent with the level of methane flow (the so-called “emission factor”) typically released by other similar manifestations of terrestrial natural gas, such as, for example, the mud volcanoes.
This means that if the measurements from these sites were combined globally, the global estimates would come to indicate a geological methane emission closer to that defined with statistical criteria, based on flows measured on the ground (of the order of 50 million tons of methane per year), rather than the practically negligible one based on the evaluations carried out with radiocarbon in ice cores.
“Knowing the real quantities and flows of methane from natural geological sources is particularly important to better assess anthropogenic gas emissions, such as those related to the oil industry, and therefore the overall atmospheric methane balance. Finally, our study suggests that the measurements of gas emissions carried out with the help of satellite data can prove to be a key tool to support ground studies and improve estimates of the global geo-methane budget”, concludes Sciara.
An innovative study recently published in the journal Scientific Reports di Nature, determined the amount of methane emitted by a single natural gas show, one of the largest on the planet, called Lusi, in Indonesia. The investigation, which relies on integrating ground-based data with satellite data, would suggest that some carbon-14 (radiocarbon)-based estimates of global geological methane emissions are underreported.
Geological gas emissions from petroleum sedimentary basins are a natural component of the atmospheric methane budget.
However, the global amount of geological methane released into the atmosphere is the subject of various studies, some in conflict with each other. In fact, while statistical estimates, based on fluxes measured on the ground, suggest a global emission of about 50 million tons of methane per year, other estimates, based on analyzes of radiocarbon (carbon-14) in ice cores from the 'pre-industrial era, suggest much lower values, between 0,1 and 5,4 million tons per year.
The study now published was conducted by the Center for Earth Evolution and Dynamics (CEED) of the University of Oslo (Norway) in collaboration with the National Institute of Geophysics and Volcanology (INGV), with the Netherlands Institute for Space Research in Utrecht ( SRON) and with the Indonesian agency Pusat Pengendalian Lumpur Sidoarjo (PPLS).
The researchers analyzed the spectacular methane gas emission event that developed in 2006 on the island of Java, Indonesia. The area, nicknamed Lusi, has since continued to emit water, oil, gas and mud, with eruptions capable of expelling up to 180.000 m3 of mud per day and plumes of steam reaching several tens of meters in height.
“The results we have obtained after years of monitoring”, explains Alessandra Sciarra, INGV researcher and co-author of the study, “They delve into the scientific debate about the global emission of geological methane sources and suggest that some of the recent estimates based on analyzes of ancient ice cores are significantly underestimated. In fact, the amount of methane released by Lusi already corresponds to the minimum assessment of the studies for the entire planet based on ice cores".
Lusi is a geological phenomenon fueled by high fluid pressures in sedimentary rocks and high temperatures resulting from interaction with the nearby Arjuno-Welirang volcanic complex. It is, therefore, the surface manifestation of a hybrid sedimentary-hydrothermal system. The escaping gas, rich in carbon dioxide (CO2) and methane (CH4), is ejected into the atmosphere from two central craters and from thousands of minor emission points (satellite seep) covering an area of 7,5 km2. Until now, the amount of gas actually released into the atmosphere from this site was unknown.
“Our research group has combined techniques of measurements from the ground and from a satellite, called TROPOMI, to quantify the gas released into the atmosphere by Lusi”continues Sciara. “The two techniques indicated similar methane emission values of approximately 100.000 tons per year – the highest methane emission ever measured from a single gas event”.
The results obtained by the researchers suggest that the amount of methane gas emitted by Lusi is proportionally consistent with the level of methane flux (the so-called "emission factor") typically released by other similar manifestations of terrestrial natural gas such as, for example, mud volcanoes.
This means that if the measurements from these sites were combined worldwide, the global estimates would come to indicate a geological methane emission closer to that defined with statistical criteria, based on the fluxes measured on the ground (of the order of 50 million tons of methane per year), rather than the practically negligible one based on evaluations made with radiocarbon in ice cores.
“Knowing the actual quantities and flows of methane from natural geological sources is particularly important for better assessing anthropogenic gas emissions, such as those related to the oil industry, and therefore the overall atmospheric methane balance. Finally, our study suggests that measurements of gas emissions carried out with the help of satellite data can prove to be a key tool to support ground studies and improve estimates of the global geo-methane budget”Sciara concludes.
---
INGV. The natural geological emission of methane into the atmosphere evaluated through the integrated use of a satellite and measurements on the ground
The analysis carried out on the Island of Java, Indonesia, have made it possible to determine the largest geological methane emission ever measured so far
An innovative study recently published in Nature's Scientific Reports, determined the amount of methane emitted by a single manifestation of natural gas, one of the largest on the planet, called Lusi, in Indonesia. The survey, which is based on the integration of data acquired on the ground with satellite data, would suggest that some estimates of global emissions of geological methane based on carbon-14 (radiocarbon) are underestimated.
Geological emissions of gas from sedimentary oil basins are a natural component of the atmospheric methane budget.
However, the global amount of geological methane released into the atmosphere is the subject of various studies, some at odds with each other. In fact, while the statistical estimates, based on the flows measured on the ground, suggest a global emission of about 50 million tons of methane per year, other estimates, based on analysis of radiocarbon (carbon-14) in ice cores of the pre -industrial era, suggest much lower values, between 0.1 and 5.4 million tons per year.
The study now published was conducted by the Center for Earth Evolution and Dynamics (CEED) of the University of Oslo (Norway) in collaboration with the National Institute of Geophysics and Volcanology (INGV), the Netherlands Institute for Space Research in Utrecht ( SRON) and the Indonesian agency Pusat Pengendalian Lumpur Sidoarjo (PPLS).
The researchers analyzed the spectacular manifestation of methane gas emission that developed in 2006 on the island of Java, Indonesia. The area, nicknamed Lusi, has continued to emit water, oil, gas and mud ever since, with eruptions capable of expelling up to 180,000 m3 of mud per day and plumes of steam reaching several tens of meters in height.
“The results we have obtained after years of monitoring", explains Alessandra Sciarra, researcher at INGV and co-author of the study, “deepen the scientific debate on the global emission of geological sources of methane and suggest that some of the recent estimates based on analysis of ancient ice cores are significantly underestimated. In fact, the quantity of methane released by Lusi already corresponds by itself to the minimum evaluation of the studies for the entire planet based on ice cores”.
Lusi is a geological phenomenon fueled by the high pressures of fluids in sedimentary rocks and by the high temperatures resulting from the interaction with the nearby Arjuno-Welirang volcanic complex. It is therefore the superficial manifestation of a sedimentary-hydrothermal hybrid system. The gas that escapes, rich in carbon dioxide (CO2) and methane (CH4), is expelled into the atmosphere by two central craters and by thousands of minor emission points (satellite seeps) covering an area of 7.5 km2. Until now, the amount of gas actually released into the atmosphere from this site was unknown.
“Our research group has combined measurement techniques from the ground and from a satellite, called TROPOMI, to quantify the gas released into the atmosphere by Lusi”, continuesSciarra. “The two techniques indicated similar methane emission values, of about 100,000 tons per year: this is the highest methane emission ever measured by a single manifestation of gas”.
The results obtained by the researchers suggest that the amount of methane gas emitted by Lusi is proportionally consistent with the level of methane flow (the so-called “emission factor”) typically released by other similar manifestations of terrestrial natural gas, such as, for example, the mud volcanoes.
This means that if the measurements from these sites were combined globally, the global estimates would come to indicate a geological methane emission closer to that defined with statistical criteria, based on flows measured on the ground (of the order of 50 million tons of methane per year), rather than the practically negligible one based on the evaluations carried out with radiocarbon in ice cores.
“Knowing the real quantities and flows of methane from natural geological sources is particularly important to better assess anthropogenic gas emissions, such as those related to the oil industry, and therefore the overall atmospheric methane balance. Finally, our study suggests that the measurements of gas emissions carried out with the help of satellite data can prove to be a key tool to support ground studies and improve estimates of the global geo-methane budget”, concludes Sciara.
