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E Boschi - One of the best experts on this subject based on the ideXlab platform.
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did the september 2010 darfield Earthquake Trigger the february 2011 christchurch event
Scientific Reports, 2011Co-Authors: Salvatore Stramondo, C Kyriakopoulos, Christian Bignami, Marco Chini, Daniele Melini, Marco Moro, M Picchiani, Michele Saroli, E BoschiAbstract:Did the September 2010 (Darfield) Earthquake Trigger the February 2011 (Christchurch) event?
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reply to comment by m dumberry on could the mw 9 3 sumatra Earthquake Trigger a geomagnetic jerk
Eos Transactions American Geophysical Union, 2005Co-Authors: Fabio Florindo, Paola De Michelis, A Piersanti, E BoschiAbstract:We thank M. Dumberry for providing the opportunity to discuss further the article [Florindo et al., 2005] in which we suggested that the Sumatra Earthquake could have Triggered a geomagnetic jerk. Dumberry is against our hypothesis for different reasons: (1) The displacement pattern produced by this Earthquake is incompatible with the core-mantle boundary (CMB) deformations required for a torsional oscillation; (2) most of the deformations occurred locally, producing an actual mass displacement that has not involved the entire Earth; and (3) no abrupt change in the length of day (LOD) has been observed after this event.
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could the mw 9 3 sumatra Earthquake Trigger a geomagnetic jerk
Eos Transactions American Geophysical Union, 2005Co-Authors: Fabio Florindo, Paola De Michelis, A Piersanti, E BoschiAbstract:The magnetic field observed at the Earth's surface is not a stationary feature. It is characterized by time variations ranging from milliseconds (micropulsations) to millions of years (the time interval between field reversals). Time variations with periods of a year or longer are related to Earth's outer core sources, whereas for shorter timescales an external origin is invoked (i.e.,solar activity). One of the most interesting time variations of the geomagnetic field is represented by the “geomagnetic jerk.” It is idealized as a rapid change in the slope of the secular variation, defined as the first derivative of the geomagnetic field. This means that the secular variation roughly appears as a series of straightline segments separated by geomagnetic jerks.
Michael Manga - One of the best experts on this subject based on the ideXlab platform.
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sawolo et al 2009 the lusi mud volcano controversy was it caused by drilling
Marine and Petroleum Geology, 2010Co-Authors: Richard J Davies, Michael Manga, Mark Tingay, Susila Lusianga, Richard E SwarbrickAbstract:1. IntroductionThe Lusi mud volcano in Sidoarjo, East Java, was first noticed bylocal villagers at 5 am on the 29th May 2006. It started to erupt150 mfromtheBanjarPanji-1gasexplorationwell(Fig.1)twodaysafter the Yogyakarta Earthquake (5:54 am 27th May 2006), hasdisplaced 13,000 families and led to13 fatalities. The Trigger for themud volcano has been the subject of significant debate (Davieset al., 2007, 2008; Manga, 2007; Mazzini et al., 2007; Tingayet al., 2008).The Sawolo et al. (2009) paper assesses and then dismisses thepossibility that there was a subsurface blowout (breakdown of thestructural integrity of the well) caused by a kick in the well (aninflux of water or gas from surrounding formations) whichoccurred on the 27th and 28th May 2006. For the subsurfaceblowout to have occurred, the pressure of the fluid (drilling mud,water, gas) in the unprotected section of the well has to exceed themaximum pressure the well can tolerate, which is estimated bya pressure test known as a leak-off test (LOT). To reach thisconclusion Sawolo et al. (2009) estimate what we deem to be anunrealistically high leak-off pressure (LOP) and unrealistically lowpressure within the borehole during the kick.Here we counter the main arguments made by Sawolo et al.(2009), pointing out inaccuracies, incorrect interpretations anddeviations from the daily drilling report (the factual account ofdaily operations). We also take this opportunity to describe for thefirst time direct evidence that the well was the cause of the mudvolcano. Lastly we show that their claim of an Earthquake Trigger isnot supported by the mud log data they present.2. What pressure could the well tolerate?The estimated LOP proposed by Sawolo et al. (2009) is 16.4 ppg(19.27 MPa/km) measured at 1091 m (1 ppg¼1.175 MPa/km). Indetermining the leak-off pressure (LOP), industryaccepted practiceis to take the inflexion point on a pressure build-up curve (Bell,1996; Enever et al., 1996; Addis et al., 1998; Jorgensen andFejerskov, 1998; Okland et al., 2002; Raaen et al., 2006; van Oortand Vargo, 2008). Based upon the pressure versus time plot(their figure 11), using this method the leak off was 15.8 ppg(18.57 MPa/km). The rationale stated by Sawolo et al. (2009) fornot interpreting the LOP by the conventional method is thatinterpreting leak-off pressure is less reliable when using oil-basedmuds and they suggest that the ‘fracture closure pressure’ shouldbe used instead.The fracture closure pressure (FCP) is generallyconsidered to beequaltotheminimum principalstressmagnitude andthus equaltothepressurerequiredtoopenanypre-existingfractures.Hence,theFCPcanbeanaccuratevaluetouseasformationstrength.However,the 16.4 ppg (19.27 MPa/km) value suggested by Sawolo et al.(2009) as the ‘fracture closure pressure’ is in contravention of alltechniques for estimating FCP. FCP is determined by carefullymonitoring the pressure decay in the well after the pumps areturned off (Enever et al., 1996; Jorgensen and Fejerskov, 1998;Raaen et al., 2006). The FCP can then be estimated from the pres-sure decay curve by a variety of methods, with the double tangentor root time methods most commonly used (Enever, 1993; Raaenet al., 2006). These techniques all require the pressure decay tobe monitored for a long duration after the pumps are shut-in(generally >10 min; Enever et al., 1996; Jorgensen and Fejerskov,
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the east java mud volcano 2006 to present an Earthquake or drilling Trigger
Earth and Planetary Science Letters, 2008Co-Authors: Richard J Davies, Michael Manga, Richard E Swarbrick, Maria Brumm, Rudi Rubiandini, Mark TingayAbstract:Abstract On May 29th 2006 a mud volcano, later to be named ‘Lusi’, started to form in East Java. It is still active and has displaced > 30,000 people. The Trigger mechanism for this, the world's largest and best known active mud volcano, is still the subject of debate. Trigger mechanisms considered here are (a) the May 27th 2006 Yogyakarta Earthquake, (b) the drilling of the nearby Banjar Panji-1 gas exploration well (150 m away), and (c) a combination of the Earthquake and drilling operations. We compare the distance and magnitude of the Earthquake with the relationship between the distance and magnitude of historical Earthquakes that have caused sediment liquefaction, or Triggered the eruption of mud volcanoes or caused other hydrological responses. Based on this comparison, an Earthquake Trigger is not expected. The static stress changes caused by the rupture of the fault that created the Yogyakarta Earthquake are a few tens of Pascals, much smaller than changes in stress caused by tides or variations in barometric pressure. At least 22 Earthquakes (and possibly hundreds) likely caused stronger ground shaking at the site of Lusi in the past 30 years without causing an eruption. The period immediately preceding the eruption was seismically quieter than average and thus there is no evidence that Lusi was “primed” by previous Earthquakes. We thus rule out an Earthquake-only Trigger. The day before the eruption started (May 28th 2006), as a result of pulling the drill bit and drill pipe out of the hole, there was a significant influx of formation fluid and gas. The monitored pressure after the influx, in the drill pipe and annulus showed variations typical of the leakage of drilling fluid into the surrounding sedimentary rock strata. Furthermore we calculate that the pressure at a depth of 1091 m (the shallowest depth without any protective steel casing) exceeded a critical level after the influx occurred. Fractures formed due to the excess pressure, allowing a fluid-gas-mud mix to flow to the surface. With detailed data from the exploration well, we can now identify the specific drilling induced phenomena that caused this man-made disaster.
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did an Earthquake Trigger the may 2006 eruption of the lusi mud volcano
Eos Transactions American Geophysical Union, 2007Co-Authors: Michael MangaAbstract:On 29 May 2006, a mud volcano, unofficially named ‘Lusi,’ erupted in the Indonesian city of Sidoarjo, in eastern Java, covering an area of several square kilometers with mud [Davies et al., 2007] and displacing more than 24,000 people [Cyranoski, 2007]. Two days earlier, a magnitude 6.3 Earthquake occurred approximately 250 kilometers to the southeast. A 2800-meter-deep exploratory gas well, located about 200 meters from the mud eruption, experienced control problems within 5–7 hours of the Earthquake (R.J. Davies, personal communication, 2007) indicating changes in fluid pressures soon after this Earthquake. This Earthquake is coincident with changes in eruptive behavior at nearby magmatic volcanoes [Harris and Ripepe, 2007; Walter et al., 2007]. Did the Earthquake Trigger the eruption of the Lusi mud volcano?
Dylan H Rood - One of the best experts on this subject based on the ideXlab platform.
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millennial scale record of landslides in the andes consistent with Earthquake Trigger
Nature Geoscience, 2014Co-Authors: Devin Mcphillips, Paul R Bierman, Dylan H RoodAbstract:Landslide deposits are often interpreted as the consequence of precipitation. A millennial-scale record of landslides, inferred from river cobbles in the arid Andes, is instead consistent with Earthquake Triggering.
Richard E Swarbrick - One of the best experts on this subject based on the ideXlab platform.
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sawolo et al 2009 the lusi mud volcano controversy was it caused by drilling
Marine and Petroleum Geology, 2010Co-Authors: Richard J Davies, Michael Manga, Mark Tingay, Susila Lusianga, Richard E SwarbrickAbstract:1. IntroductionThe Lusi mud volcano in Sidoarjo, East Java, was first noticed bylocal villagers at 5 am on the 29th May 2006. It started to erupt150 mfromtheBanjarPanji-1gasexplorationwell(Fig.1)twodaysafter the Yogyakarta Earthquake (5:54 am 27th May 2006), hasdisplaced 13,000 families and led to13 fatalities. The Trigger for themud volcano has been the subject of significant debate (Davieset al., 2007, 2008; Manga, 2007; Mazzini et al., 2007; Tingayet al., 2008).The Sawolo et al. (2009) paper assesses and then dismisses thepossibility that there was a subsurface blowout (breakdown of thestructural integrity of the well) caused by a kick in the well (aninflux of water or gas from surrounding formations) whichoccurred on the 27th and 28th May 2006. For the subsurfaceblowout to have occurred, the pressure of the fluid (drilling mud,water, gas) in the unprotected section of the well has to exceed themaximum pressure the well can tolerate, which is estimated bya pressure test known as a leak-off test (LOT). To reach thisconclusion Sawolo et al. (2009) estimate what we deem to be anunrealistically high leak-off pressure (LOP) and unrealistically lowpressure within the borehole during the kick.Here we counter the main arguments made by Sawolo et al.(2009), pointing out inaccuracies, incorrect interpretations anddeviations from the daily drilling report (the factual account ofdaily operations). We also take this opportunity to describe for thefirst time direct evidence that the well was the cause of the mudvolcano. Lastly we show that their claim of an Earthquake Trigger isnot supported by the mud log data they present.2. What pressure could the well tolerate?The estimated LOP proposed by Sawolo et al. (2009) is 16.4 ppg(19.27 MPa/km) measured at 1091 m (1 ppg¼1.175 MPa/km). Indetermining the leak-off pressure (LOP), industryaccepted practiceis to take the inflexion point on a pressure build-up curve (Bell,1996; Enever et al., 1996; Addis et al., 1998; Jorgensen andFejerskov, 1998; Okland et al., 2002; Raaen et al., 2006; van Oortand Vargo, 2008). Based upon the pressure versus time plot(their figure 11), using this method the leak off was 15.8 ppg(18.57 MPa/km). The rationale stated by Sawolo et al. (2009) fornot interpreting the LOP by the conventional method is thatinterpreting leak-off pressure is less reliable when using oil-basedmuds and they suggest that the ‘fracture closure pressure’ shouldbe used instead.The fracture closure pressure (FCP) is generallyconsidered to beequaltotheminimum principalstressmagnitude andthus equaltothepressurerequiredtoopenanypre-existingfractures.Hence,theFCPcanbeanaccuratevaluetouseasformationstrength.However,the 16.4 ppg (19.27 MPa/km) value suggested by Sawolo et al.(2009) as the ‘fracture closure pressure’ is in contravention of alltechniques for estimating FCP. FCP is determined by carefullymonitoring the pressure decay in the well after the pumps areturned off (Enever et al., 1996; Jorgensen and Fejerskov, 1998;Raaen et al., 2006). The FCP can then be estimated from the pres-sure decay curve by a variety of methods, with the double tangentor root time methods most commonly used (Enever, 1993; Raaenet al., 2006). These techniques all require the pressure decay tobe monitored for a long duration after the pumps are shut-in(generally >10 min; Enever et al., 1996; Jorgensen and Fejerskov,
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the east java mud volcano 2006 to present an Earthquake or drilling Trigger
Earth and Planetary Science Letters, 2008Co-Authors: Richard J Davies, Michael Manga, Richard E Swarbrick, Maria Brumm, Rudi Rubiandini, Mark TingayAbstract:Abstract On May 29th 2006 a mud volcano, later to be named ‘Lusi’, started to form in East Java. It is still active and has displaced > 30,000 people. The Trigger mechanism for this, the world's largest and best known active mud volcano, is still the subject of debate. Trigger mechanisms considered here are (a) the May 27th 2006 Yogyakarta Earthquake, (b) the drilling of the nearby Banjar Panji-1 gas exploration well (150 m away), and (c) a combination of the Earthquake and drilling operations. We compare the distance and magnitude of the Earthquake with the relationship between the distance and magnitude of historical Earthquakes that have caused sediment liquefaction, or Triggered the eruption of mud volcanoes or caused other hydrological responses. Based on this comparison, an Earthquake Trigger is not expected. The static stress changes caused by the rupture of the fault that created the Yogyakarta Earthquake are a few tens of Pascals, much smaller than changes in stress caused by tides or variations in barometric pressure. At least 22 Earthquakes (and possibly hundreds) likely caused stronger ground shaking at the site of Lusi in the past 30 years without causing an eruption. The period immediately preceding the eruption was seismically quieter than average and thus there is no evidence that Lusi was “primed” by previous Earthquakes. We thus rule out an Earthquake-only Trigger. The day before the eruption started (May 28th 2006), as a result of pulling the drill bit and drill pipe out of the hole, there was a significant influx of formation fluid and gas. The monitored pressure after the influx, in the drill pipe and annulus showed variations typical of the leakage of drilling fluid into the surrounding sedimentary rock strata. Furthermore we calculate that the pressure at a depth of 1091 m (the shallowest depth without any protective steel casing) exceeded a critical level after the influx occurred. Fractures formed due to the excess pressure, allowing a fluid-gas-mud mix to flow to the surface. With detailed data from the exploration well, we can now identify the specific drilling induced phenomena that caused this man-made disaster.
Mark Tingay - One of the best experts on this subject based on the ideXlab platform.
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sawolo et al 2009 the lusi mud volcano controversy was it caused by drilling
Marine and Petroleum Geology, 2010Co-Authors: Richard J Davies, Michael Manga, Mark Tingay, Susila Lusianga, Richard E SwarbrickAbstract:1. IntroductionThe Lusi mud volcano in Sidoarjo, East Java, was first noticed bylocal villagers at 5 am on the 29th May 2006. It started to erupt150 mfromtheBanjarPanji-1gasexplorationwell(Fig.1)twodaysafter the Yogyakarta Earthquake (5:54 am 27th May 2006), hasdisplaced 13,000 families and led to13 fatalities. The Trigger for themud volcano has been the subject of significant debate (Davieset al., 2007, 2008; Manga, 2007; Mazzini et al., 2007; Tingayet al., 2008).The Sawolo et al. (2009) paper assesses and then dismisses thepossibility that there was a subsurface blowout (breakdown of thestructural integrity of the well) caused by a kick in the well (aninflux of water or gas from surrounding formations) whichoccurred on the 27th and 28th May 2006. For the subsurfaceblowout to have occurred, the pressure of the fluid (drilling mud,water, gas) in the unprotected section of the well has to exceed themaximum pressure the well can tolerate, which is estimated bya pressure test known as a leak-off test (LOT). To reach thisconclusion Sawolo et al. (2009) estimate what we deem to be anunrealistically high leak-off pressure (LOP) and unrealistically lowpressure within the borehole during the kick.Here we counter the main arguments made by Sawolo et al.(2009), pointing out inaccuracies, incorrect interpretations anddeviations from the daily drilling report (the factual account ofdaily operations). We also take this opportunity to describe for thefirst time direct evidence that the well was the cause of the mudvolcano. Lastly we show that their claim of an Earthquake Trigger isnot supported by the mud log data they present.2. What pressure could the well tolerate?The estimated LOP proposed by Sawolo et al. (2009) is 16.4 ppg(19.27 MPa/km) measured at 1091 m (1 ppg¼1.175 MPa/km). Indetermining the leak-off pressure (LOP), industryaccepted practiceis to take the inflexion point on a pressure build-up curve (Bell,1996; Enever et al., 1996; Addis et al., 1998; Jorgensen andFejerskov, 1998; Okland et al., 2002; Raaen et al., 2006; van Oortand Vargo, 2008). Based upon the pressure versus time plot(their figure 11), using this method the leak off was 15.8 ppg(18.57 MPa/km). The rationale stated by Sawolo et al. (2009) fornot interpreting the LOP by the conventional method is thatinterpreting leak-off pressure is less reliable when using oil-basedmuds and they suggest that the ‘fracture closure pressure’ shouldbe used instead.The fracture closure pressure (FCP) is generallyconsidered to beequaltotheminimum principalstressmagnitude andthus equaltothepressurerequiredtoopenanypre-existingfractures.Hence,theFCPcanbeanaccuratevaluetouseasformationstrength.However,the 16.4 ppg (19.27 MPa/km) value suggested by Sawolo et al.(2009) as the ‘fracture closure pressure’ is in contravention of alltechniques for estimating FCP. FCP is determined by carefullymonitoring the pressure decay in the well after the pumps areturned off (Enever et al., 1996; Jorgensen and Fejerskov, 1998;Raaen et al., 2006). The FCP can then be estimated from the pres-sure decay curve by a variety of methods, with the double tangentor root time methods most commonly used (Enever, 1993; Raaenet al., 2006). These techniques all require the pressure decay tobe monitored for a long duration after the pumps are shut-in(generally >10 min; Enever et al., 1996; Jorgensen and Fejerskov,
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the east java mud volcano 2006 to present an Earthquake or drilling Trigger
Earth and Planetary Science Letters, 2008Co-Authors: Richard J Davies, Michael Manga, Richard E Swarbrick, Maria Brumm, Rudi Rubiandini, Mark TingayAbstract:Abstract On May 29th 2006 a mud volcano, later to be named ‘Lusi’, started to form in East Java. It is still active and has displaced > 30,000 people. The Trigger mechanism for this, the world's largest and best known active mud volcano, is still the subject of debate. Trigger mechanisms considered here are (a) the May 27th 2006 Yogyakarta Earthquake, (b) the drilling of the nearby Banjar Panji-1 gas exploration well (150 m away), and (c) a combination of the Earthquake and drilling operations. We compare the distance and magnitude of the Earthquake with the relationship between the distance and magnitude of historical Earthquakes that have caused sediment liquefaction, or Triggered the eruption of mud volcanoes or caused other hydrological responses. Based on this comparison, an Earthquake Trigger is not expected. The static stress changes caused by the rupture of the fault that created the Yogyakarta Earthquake are a few tens of Pascals, much smaller than changes in stress caused by tides or variations in barometric pressure. At least 22 Earthquakes (and possibly hundreds) likely caused stronger ground shaking at the site of Lusi in the past 30 years without causing an eruption. The period immediately preceding the eruption was seismically quieter than average and thus there is no evidence that Lusi was “primed” by previous Earthquakes. We thus rule out an Earthquake-only Trigger. The day before the eruption started (May 28th 2006), as a result of pulling the drill bit and drill pipe out of the hole, there was a significant influx of formation fluid and gas. The monitored pressure after the influx, in the drill pipe and annulus showed variations typical of the leakage of drilling fluid into the surrounding sedimentary rock strata. Furthermore we calculate that the pressure at a depth of 1091 m (the shallowest depth without any protective steel casing) exceeded a critical level after the influx occurred. Fractures formed due to the excess pressure, allowing a fluid-gas-mud mix to flow to the surface. With detailed data from the exploration well, we can now identify the specific drilling induced phenomena that caused this man-made disaster.