The Sidoarjo mud flow (commonly known as ''Lumpur Lapindo,'' wherein ''lumpur'' is the
Indonesian
Indonesian is anything of, from, or related to Indonesia, an archipelagic country in Southeast Asia. It may refer to:
* Indonesians, citizens of Indonesia
** Native Indonesians, diverse groups of local inhabitants of the archipelago
** Indonesian ...
word for mud) is the result of an erupting
mud volcano
A mud volcano or mud dome is a landform created by the eruption of mud or slurries, water and gases. Several geological processes may cause the formation of mud volcanoes. Mud volcanoes are not true igneous volcanoes as they do not produce lava ...
in the subdistrict of
Porong
Porong is a district in Sidoarjo Regency, East Java, Indonesia. It has a population of 68,243 (2018). Located about south of the regency seat, it bordered by Krembung in the west, Pasuruan Regency in the south, Tanggulangin in the north.
Villages ...
,
Sidoarjo
Sidoarjo Regency ( jv, ꦑꦧꦸꦥꦠꦺꦤ꧀ꦱꦶꦢꦲꦂꦗ, Kabupatèn Sidaharja) is a regency in East Java, Indonesia. It is bordered by Surabaya city and Gresik Regency to the north, by Pasuruan Regency to the south, by Mojokerto Regency ...
in
East Java
East Java ( id, Jawa Timur) is a Provinces of Indonesia, province of Indonesia located in the easternmost hemisphere of Java island. It has a land border only with the province of Central Java to the west; the Java Sea and the Indian Ocean bord ...
,
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...
that has been in eruption since May 2006. It is the biggest mud volcano in the world; responsibility for it was credited to the
blowout of a
natural gas
Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbo ...
well drilled by
PT Lapindo Brantas
PT Lapindo Brantas is an Indonesian oil and gas exploration company. It was established as a joint venture between PT. Energi Mega Persada Tbk. (50%), PT. Medco Energi Tbk. (32%) and Santos Australia (18%). The Bakrie family, through its investm ...
, although company officials contend it was caused by a very
distant earthquake that occurred in a different province.
At its peak it spewed up to of mud per day.
By mid August 2011, mud was being discharged at a rate of per day, with 15 bubbles around its gushing point. This was a significant decline from the previous year, when mud was being discharged at a rate of per day with 320 bubbles around its gushing point. It is expected that the flow will continue for the next 25 to 30 years.
Although the Sidoarjo mud flow has been contained by
levee
A levee (), dike (American English), dyke (English in the Commonwealth of Nations, Commonwealth English), embankment, floodbank, or stop bank is a structure that is usually soil, earthen and that often runs parallel (geometry), parallel to ...
s since November 2008, resultant floodings regularly disrupt local highways and villages, and further breakouts of mud are still possible.
[Sidoarjo mud flow](_blank)
from NASA's Earth Observatory
NASA Earth Observatory is an online publishing outlet for NASA which was created in 1999. It is the principal source of satellite imagery and other scientific information pertaining to the climate and the environment which are being provided by N ...
, posted December 10, 2008. This article incorporates public domain
The public domain (PD) consists of all the creative work
A creative work is a manifestation of creative effort including fine artwork (sculpture, paintings, drawing, sketching, performance art), dance, writing (literature), filmmaking, ...
text and images from this NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
webpage.
Geological setting
Mud volcano systems are fairly common on Earth, and particularly in the Indonesian province of
East Java
East Java ( id, Jawa Timur) is a Provinces of Indonesia, province of Indonesia located in the easternmost hemisphere of Java island. It has a land border only with the province of Central Java to the west; the Java Sea and the Indian Ocean bord ...
. Beneath the island of Java is a
half-graben
A half-graben is a geological structure bounded by a fault along one side of its boundaries, unlike a full graben where a depressed block of land is bordered by parallel faults.
Rift and fault structure
A rift is a region where the lithosphere ...
lying in the east–west direction, filled with over-pressured marine
carbonate
A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonate g ...
s and marine muds. It forms an
inverted extensional
basin which has been geologically active since the
Paleogene
The Paleogene ( ; British English, also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period, geologic period and system that spans 43 million years from the end of the Cretaceous Period million yea ...
epoch. The basin started to become overpressured during the
Oligo-
Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
period. Some of the overpressured mud escapes to the surface to form mud volcanoes, which have been observed at
Sangiran Dome near
Surakarta
Surakarta ( jv, ꦯꦸꦫꦏꦂꦠ), known colloquially as Solo ( jv, ꦱꦭ; ), is a city in Central Java, Indonesia. The 44 km2 (16.2 sq mi) city adjoins Karanganyar Regency and Boyolali Regency to the north, Karanganyar Regency and Sukoh ...
(Solo) in Central Java and near
Purwodadi city, west of Lusi.
The East Java Basin contains a significant amount of
oil
An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturated ...
and
gas
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or ...
reserves, therefore the region is known as a major concession area for mineral exploration. The
Porong
Porong is a district in Sidoarjo Regency, East Java, Indonesia. It has a population of 68,243 (2018). Located about south of the regency seat, it bordered by Krembung in the west, Pasuruan Regency in the south, Tanggulangin in the north.
Villages ...
subdistrict, 14 km south of
Sidoarjo
Sidoarjo Regency ( jv, ꦑꦧꦸꦥꦠꦺꦤ꧀ꦱꦶꦢꦲꦂꦗ, Kabupatèn Sidaharja) is a regency in East Java, Indonesia. It is bordered by Surabaya city and Gresik Regency to the north, by Pasuruan Regency to the south, by Mojokerto Regency ...
city, is known in the
mineral industry
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic via ...
as the Brantas Production Sharing Contract (PSC), an area of approximately 7,250 km
2 which consists of three oil and gas fields: Wunut, Carat and Tanggulangin. As of 2006, three companies—
Santos (18%),
MedcoEnergi
PT Medco Energi Internasional Tbk or MedcoEnergi is an Indonesian oil and gas company. The company operates in Trading and Holding & Related Operations, Exploration for and Production of Oil & Gas, Power, Services, Chemicals and Rental of prope ...
(32%) and
PT Lapindo Brantas
PT Lapindo Brantas is an Indonesian oil and gas exploration company. It was established as a joint venture between PT. Energi Mega Persada Tbk. (50%), PT. Medco Energi Tbk. (32%) and Santos Australia (18%). The Bakrie family, through its investm ...
(50%)—had concession rights for this area; PT Lapindo Brantas acted as an operator.
Chronology
On May 28, 2006, PT Lapindo Brantas targeted gas in the Kujung Formation carbonates in the Brantas PSC area by drilling a
borehole
A borehole is a narrow shaft bored in the ground, either vertically or horizontally. A borehole may be constructed for many different purposes, including the extraction of water ( drilled water well and tube well), other liquids (such as petro ...
named the 'Banjar-Panji 1 exploration well'. In the first stage of drilling the
drill string
A drill string on a drilling rig is a column, or string, of drill pipe that transmits drilling fluid (via the mud pumps) and torque (via the kelly drive or top drive) to the Well drilling#Drill bits in mechanical drilling, drill bit. The term ...
first went through a thick
clay seam (500–1,300 m deep), then through sands, shales,
volcanic debris and finally into permeable
carbonate rock
Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major types are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO3), and dolomite rock (also known as dolosto ...
s.
The Banjar Panji-1 borehole was cased down to 1,091 m (3,579 ft). At 5:00 a.m. local time (
UTC+7
UTC+07:00 is an identifier for a time offset from UTC of +07:00. In ISO 8601 the associated time would be written as . It is 7 hours ahead of UTC, meaning that when the time in UTC areas is midnight (00:00), the time in UTC+07:00 areas would ...
) on the 29th of May 2006, after the well had reached a total depth of 2,834 m (9,298 ft), this time without a protective casing, water, steam and a small amount of gas erupted at a location about 200 m southwest of the well.
Two further eruptions occurred on the second and the third of June about 800–1,000 m northwest of the well, but these stopped on June 5, 2006.
During these eruptions,
hydrogen sulfide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. The unde ...
gas was released and local villagers observed hot mud, thought to be at a temperature of around .
A
magnitude 6.3 earthquake occurred in Yogyakarta at ~06:00 local time 27 May 2006, approximately Southwest of Sidoarjo. It has been suggested that a small (20 barrel) mud loss occurred in the Banjar Panji-1 well seven minutes after the Yogyakarta earthquake (consistent with the time taken for the earthquake seismic waves to reach the Lusi location),
though there is no clear report of these losses in the drilling data, and it has also been alternatively reported that these losses occurred one hour before the earthquake.
The well suffered a complete loss of circulation at 12:50 p.m. local time on the 26th May 2006, which was between 1.5 and 4.75 hours after three large aftershocks.
A loss of circulation happens when drilling mud—necessary for maintenance of wellbore stability—that is pumped down a shaft does not return to the surface but is lost into some opening or a fault system. This mud loss problem was finally stopped when loss circulation material was pumped into the well, a standard practice in drilling an oil and gas well. A day later the well suffered a ‘kick’, an influx of formation fluid into the well bore. The kick was reported by Lapindo Brantas drilling engineers as having been killed within three hours,
though alternative interpretations of drilling records, specifically ongoing fluctuations in downhole drillpipe pressure, indicate that the kick continued for at least 24 hours.
Early the next day, on 29 May 2006, steam, water and mud began erupting up to above the well, a phenomenon that is now known as the Lusi mud volcano. Dense drilling mud and cement were pumped down the Banjar Panji-1 well at various times in the 48 hours after the mud flow started, in an attempt to kill the surface mud eruption.
Lapindo Brantas daily drilling records state that "bubbles intensity reduced and elapse time between each bubble is longer" after pumping dense drilling mud down the well,
indicating direct communication between Banjar Panji-1 and the Sidoarjo mudflow.
A detailed review of the timing of key events in the drilling of Banjar Panji-1 and the first days of the Sidoarjo mudflow can be found in reference.
Possible causes
The birth of Lusi was a major disaster for the population living nearby, with loss of their houses, properties and their livelihood.
For the scientific community, however, it was a chance to study the evolving geological process of a mud volcano. In the past, mud vulcanologists could only study existing or ancient mud volcanoes during dormant periods. Thus, Lusi is a rare occasion and a unique opportunity to conduct scientific experiments to further our understanding. It also offers opportunities to study the down hole condition of a mud volcano from the neighboring Banjar-Panji exploration well lithologies.
To explain what triggered the mud volcano, three hypotheses have been suggested, though none has won universal support:
* Drilling-induced fracturing or fault reactivation (reflecting a man-made event)
* Earthquake-triggered fault reactivation (reflecting a natural event)
* Geothermal processes (reflecting geothermal heating)
Drilling-induced fracturing
From a model developed by geologists working in the
UK,
the drilling pipe penetrated the overpressured
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
, causing
entrainment
Entrainment may refer to:
* Air entrainment, the intentional creation of tiny air bubbles in concrete
* Brainwave entrainment, the practice of entraining one's brainwaves to a desired frequency
* Entrainment (biomusicology), the synchronization o ...
of mud by water. Whilst pulling the drill string out of the well, there were ongoing losses of drilling mud, as demonstrated by the daily drilling reports stating "overpull increasing", "only 50% returns" and "unable to keep hole full".
The loss of drilling mud and associated drop in downhole mud weight eventually resulted in a drilling kick, with over 365 barrels of fluid erupting at the Banjar Panji-1 wellhead.
Blowout preventers were closed to help kill the kick, which resulted in a spike in downhole pressure within the wellbore.
The drilling-induced triggering model proposes that the increase in pressure within the wellbore was sufficiently high to induce a large hydraulic fracture in the formation.
The extra pressure caused the hydraulic fractures to propagate 1–2 km to the surface and emerged 200 m away from the well. The lack of protective casing in the bottom 1742m of the borehole is considered a key reason why the drilling kick could not be controlled and why pressures during the kick were high enough to initiate hydraulic fracturing.
Alternatively, it has also been suggested that the increased fluid pressure in the borehole, due to the kick, may have triggered reactivation of a nearby fault system, rather than hydraulic fracturing (in a similar manner to how fluid injection can induce seismicity).
Though steel casing is used to protect the well bore in oil or gas exploration, this can only be applied in stages after each new section of the hole is drilled; see
drilling for oil.
The relatively small distance, around , between the Lusi mud volcano and the well being drilled by Lapindo (the Banjarpanji well) may not be a coincidence, as less than a day before the start of the mud flow the well suffered a
kick
A kick is a physical Strike (attack), strike using the leg, in unison usually with an area of the knee or lower using the foot, heel, tibia (shin), ball of the foot, blade of the foot, toes or knee (the latter is also known as a knee (strike), ...
. Their analysis suggests that the well has a low resistance to a kick.
Similarly, a NE-SW crack in the surface in the drill site may be evidence of an underground blowout. The well may have suffered an underground blowout that resulted in a surface breach.
Earthquake-induced fault reactivation
The relatively close timing of the Yogyakarta earthquake, the problems of mud loss and kick in the well and the birth of the mud volcano continue to interest geoscientists. Was the mud volcano due to the same seismic event that triggered the earthquake? Geoscientists from Norway, Russia, France and Indonesia have suggested that the shaking caused by the Yogyakarta earthquake may have induced liquefaction of the underlying Kalibeng clay layer, releasing gases and causing a pressure change large enough to reactivate a major fault nearby (the Watukosek fault), creating a mud flow path that caused Lusi.
They have identified more than 10 naturally triggered mud volcanoes in the East Java province, with at least five near the Watukosek fault system, confirming that the region is prone to mud volcanism. They also showed that surface cracks surrounding Lusi predominantly run NE-SW, the direction of the Watukosek fault. Increased seep activity in the mud volcanoes along the Watukosek fault coincided with the May 27, 2006 seismic event. A major fault system may have been reactivated, resulting in the formation of a mud volcano.
Geothermal process
Lusi is near the arc of volcanoes in Indonesia where geothermal activities are abundant. The nearest volcano, the
Arjuno-Welirang
Mount Arjuno-Welirang is a stratovolcano in the province of East Java on Java, Indonesia. Mount Arjuno-Welirang lies about 50 kilometers (31 mi) south of Surabaya, and 20 kilometers (12 mi) north of Malang. It is a twin volcano, with the 'twin ...
complex, is less than 15 km away. The hot mud suggests that some form of geothermal heating from the nearby magmatic volcano may have been involved. The hot water and steam flowing from the vent, the location of Lusi near a magmatic volcano complex and its recharge system indicates that Lusi may be a geothermal phenomenon.
Investigations
Cause
There was controversy as to what triggered the eruption and whether the event was a natural disaster or not. According to PT Lapindo Brantas it was the
2006 Yogyakarta earthquake
The 2006 Yogyakarta earthquake (also known as the Bantul earthquake) occurred at with a moment magnitude of 6.4 and a maximum MSK intensity of VIII (''Damaging''). Several factors led to a disproportionate amount of damage and number of casualt ...
that triggered the mud flow eruption, and not their drilling activities.
Two days before the mud eruption, an earthquake of
moment magnitude
The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. It was defined in a 1979 pape ...
6.3 hit the south coast of
Central Java
Central Java ( id, Jawa Tengah) is a province of Indonesia, located in the middle of the island of Java. Its administrative capital is Semarang. It is bordered by West Java in the west, the Indian Ocean and the Special Region of Yogyakarta in t ...
and
Yogyakarta
Yogyakarta (; jv, ꦔꦪꦺꦴꦒꦾꦏꦂꦠ ; pey, Jogjakarta) is the capital city of Special Region of Yogyakarta in Indonesia, in the south-central part of the island of Java. As the only Indonesian royal city still ruled by a monarchy, ...
provinces killing 6,234 people and leaving 1.5 million homeless. At a hearing before the
parliamentary
A parliamentary system, or parliamentarian democracy, is a system of democracy, democratic government, governance of a sovereign state, state (or subordinate entity) where the Executive (government), executive derives its democratic legitimacy ...
members, senior executives of PT Lapindo Brantas argued that the earthquake was so powerful that it had
reactivated previously inactive faults and also creating deep underground fractures, allowing the mud to breach the surface, and that their company presence was coincidental, which should exempt them from paying compensation damage to the victims.
If the cause of the incident is determined to be natural, then the
government of Indonesia
The term Government of Indonesia ( id, Pemerintah Indonesia) can have a number of different meanings. At its widest, it can refer collectively to the three traditional branches of government – the executive branch, legislative branch and ju ...
has the responsibility to cover the damage instead. This argument was also recurrently echoed by
Aburizal Bakrie
Aburizal Bakrie (born 15 November 1946) is an Indonesian politician and a widely recognised successful businessman in Indonesia. From 2004 until 2005 Bakrie served as Indonesia's Coordinating Minister for Economy. From 2005 until 2009 he serv ...
, the Indonesian Minister of Welfare at that time, whose family firm controls the operator company PT Lapindo Brantas.
However the UK team of geologists downplayed Lapindo's argument and concluded ''"...that the earthquake that occurred two days earlier is coincidental."''
While it could have generated a new fracture system and weakened strata surrounding the Banjar-Panji 1 well, it could not have been the cause of the formation of the hydraulic fracture that created the main vent away from the borehole. Additionally there was no other mud volcano reported on Java after the earthquake and the main drilling site is away from the earthquake's
epicenter
The epicenter, epicentre () or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates.
Surface damage
Before the instrumental pe ...
. The intensity of the earthquake at the drilling site was estimated to have been only magnitude 2 on Richter scale, the same effect as a heavy truck passing over the area.
In June 2008, a report released by British, American, Indonesian, and Australian scientists, concluded that the volcano was not a natural disaster, but the result of oil and gas drilling.
Legal case
On June 5, 2006, MedcoEnergi (one partner company in the Brantas PSC area) sent a letter to PT Lapindo Brantas accusing them of breaching safety procedures during the drilling process.
The letter further attributes "gross negligence" to the operator company for not equipping the well bore with steel safety encasing. Soon afterwards then-
vice president
A vice president, also director in British English, is an officer in government or business who is below the president (chief executive officer) in rank. It can also refer to executive vice presidents, signifying that the vice president is on t ...
Jusuf Kalla
Muhammad Jusuf Kalla (; born 15 May 1942) is an Indonesian politician and businessman who served as the 10th and 12th vice president of Indonesia, the only vice president in Indonesian history to serve two non-consecutive terms in office (2004 ...
announced that PT Lapindo Brantas and the owner, the
Bakrie Group
The Bakrie Group is an Indonesian conglomerate founded by Achmad Bakrie in 1942. It has interests across various industries including mining, oil and gas, property development, infrastructure, plantations, media and telecommunications. The gr ...
, would have to compensate thousands of victims affected by the mud flows. Criminal investigations were then initiated against several senior executives of the company because the drilling operation had put the lives of local people at risk.
Aburizal Bakrie
Aburizal Bakrie (born 15 November 1946) is an Indonesian politician and a widely recognised successful businessman in Indonesia. From 2004 until 2005 Bakrie served as Indonesia's Coordinating Minister for Economy. From 2005 until 2009 he serv ...
frequently said that he is not involved in the company's operation and further distanced himself from the incident. Even in his capacity as Minister of Welfare, Aburizal Bakrie was reluctant to visit the disaster site. Aburizal Bakrie's family business group, Bakrie Group, one of the owners of PT Lapindo Brantas, had been trying to distance themselves from the Lusi incident. Afraid of being held liable for the disaster, Bakrie Group announced that they would sell PT Lapindo Brantas to an offshore company for only $2, but blocked the sale.
A further attempt was made to try to sell to a company registered in the
Virgin Islands
The Virgin Islands ( es, Islas Vírgenes) are an archipelago in the Caribbean Sea. They are geologically and biogeographically the easternmost part of the Greater Antilles, the northern islands belonging to the Puerto Rico Trench and St. Croix ...
, the Freehold Group, for US$1 million, which was also halted by the government supervisory agency for being an invalid sale.
Lapindo Brantas was asked to pay about 2.5 trillion rupiah (about US$276.8 million) to the victims and about 1.3 trillion rupiah as additional costs to stop the flow. Some analysts predict that the Bakrie Group will pursue
bankruptcy
Bankruptcy is a legal process through which people or other entities who cannot repay debts to creditors may seek relief from some or all of their debts. In most jurisdictions, bankruptcy is imposed by a court order, often initiated by the debtor ...
to avoid the cost of cleanup, which could amount to US$1 billion.
On August 15, 2006, the East Java police seized the Banjar-Panji 1 well to secure it for the court case. The Indonesian environmental watchdog,
WALHI, meanwhile had filed a lawsuit against PT Lapindo Brantas, President Susilo Bambang Yudhoyono, the Indonesian Minister of Energy, the Indonesian Minister of Environmental Affairs and local officials.
After investigations by independent experts, police had concluded the mud flow was an "underground
blow out
''Blow Out'' is a 1981 American neo-noir mystery thriller film written and directed by Brian De Palma. The film stars John Travolta as Jack Terry, a movie sound effects technician from Philadelphia who, while recording sounds for a low-budget ...
", triggered by the drilling activity. It is further noted that steel encasing lining had not been used which could have prevented the disaster. Thirteen Lapindo Brantas' executives and engineers face twelve charges of violating Indonesian laws.
Artistic
Australian artist
Susan Norrie investigated the political and ecological meaning of event in a sixteen-screen video installation at the 2007
Venice Biennale
The Venice Biennale (; it, La Biennale di Venezia) is an international cultural exhibition hosted annually in Venice, Italy by the Biennale Foundation. The biennale has been organised every year since 1895, which makes it the oldest of ...
.
Current status
2008
As of October 30, 2008, the mud flow was still ongoing at a rate of per day. By mid August 2011, mud was being discharged at a rate of 10,000 m
3 per day, with 15 bubbles around its gushing point.
One study found that the mud volcano was collapsing under its own weight, possibly beginning
caldera
A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is ...
formation. The researchers said the subsidence data could help determine how much of the local area will be affected by Lusi. Their research used GPS and satellite data recorded between June 2006 and September 2007 that showed the area affected by Lusi had subsided by between per year. The scientists found that if Lusi continued to erupt for three to 10 years at the constant rates measured during 2007 then the central part of the volcano could subside by between . They proposed that the subsidence was due to the weight of mud and collapse of rock strata due to the excavation of mud from beneath the surface. Their study also found that while some parts of Sidoarjo were subsiding, others were rising suggesting that the Watukosek fault system had been reactivated because of the eruption.
A study by a group of Indonesian geo-scientists led by Bambang Istadi predicted the area affected by the mudflow over a ten-year period. The model simulated the mud flow and its likely outcome in order to find safe locations to relocate people and affected infrastructures.
After new hot gas flows began to appear, workers started relocating families and some were injured in the process. The workers were taken to a local hospital to undergo treatment for severe burns. In Siring Barat, 319 more families were displaced and in Kelurahan Jatirejo, 262 new families were expected to be affected by the new flows of gas. Protesting families took to the streets demanding compensation which in turn added more delays to the already stressed detour road for Jalan Raya Porong and the Porong-Gempol toll road.
The Indonesian government has stated that their heart is with the people. However the cabinet meeting on how to disburse compensation has been delayed until further notice. A local official Saiful Ilah signed a statement announcing that, ''"The government is going to defend the people of Siring."'' Following this announcement protests came to an end and traffic flow returned to normal an hour later.
Stakeholder exit
The Australian oil and gas company
Santos Limited
Santos Ltd. (South Australia Northern Territory Oil Search) is an Australian oil and gas exploration and production company, with its headquarters in Adelaide, South Australia. It owns liquefied natural gas (LNG), pipeline gas, and oil assets. ...
was a minority partner in the venture until 2008. In December 2008, the company sold its 18% stake in the project to Minarak Labuan, the owner of Lapindo Brantas Inc. Labuan also received a payment from Santos of $US22.5 million ($A33.9 million) "to support long-term mud management efforts". The amount was covered by existing provision for costs relating to the incident. Santos had provisioned for $US79 million ($A119.3 million) in costs associated with the disaster. Santos had stated in June 2006 that it maintained "appropriate insurance coverage for these types of occurrences".
= 2010
=
New mudflows spots begun in April 2010, this time on Porong Highway, which is the main road linking
Surabaya
Surabaya ( jv, ꦱꦸꦫꦧꦪ or jv, ꦯꦹꦫꦨꦪ; ; ) is the capital city of the Provinces of Indonesia, Indonesian province of East Java and the List of Indonesian cities by population, second-largest city in Indonesia, after Jakarta. L ...
with
Probolinggo
Probolinggo ( id, Kota Probolinggo, mad, Prabâlingghâ) is a city on the north coast of East Java province, Indonesia. It covers an area of 56.67 sq. km, and had a population of 217,062 at the 2010 census and 239,649 at the 2020 census ...
and islands to the east including
Bali
Bali () is a province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller neighbouring islands, notably Nusa Penida, Nusa Lembongan, and Nu ...
, despite roadway thickening and strengthening. A new highway is planned to replace this one however are held up by land acquisition issues. The main railway also runs by the area, which is in danger of explosions due to seepage of methane and ignition could come from something as simple as a tossed cigarette.
As of June 2009, the residents had received less than 20% of the suggested compensation. By mid-2010, reimbursement payments for victims had not been fully settled, and legal action against the company had stalled. It is worth mentioning that the owner of the energy company,
Aburizal Bakrie
Aburizal Bakrie (born 15 November 1946) is an Indonesian politician and a widely recognised successful businessman in Indonesia. From 2004 until 2005 Bakrie served as Indonesia's Coordinating Minister for Economy. From 2005 until 2009 he serv ...
was the Coordinating Minister for People's Welfare at the time of the disaster, and is currently the chairman of ''
Golkar
)
, foundation =
, youth = AMPG (Golkar Party Young Force)
, women = KPPG (Golkar Party Women's Corps)
, newspaper = '' Suara Karya'' (1971–2016)
, headquarters = Jakarta
, ideology ...
'', one of the most influential political parties in Indonesia.
= 2011
=
In 2011, Lapindo Brantas published an independent Social Impact Report.
The Sidoarjo mud is rich in rock salt (
halite
Halite (), commonly known as rock salt, is a type of salt, the mineral (natural) form of sodium chloride ( Na Cl). Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light blue, dark blue, purple, p ...
) and has provided a source of income for the local residents who have been harvesting the salt for sale at the local market.
= 2013
=
In late 2013, international scientists who had been monitoring the situation were reported as saying that the eruption of mud at Sidoardjo was falling away quite rapidly and that the indications were that the eruption might cease by perhaps 2017, much earlier than previously estimated. The scientists noted that the system was losing pressure quite rapidly and had begun pulsing rather than maintaining a steady flow. The pulsing pattern, it was believed, was a clear sign that the geological forces driving the eruption were subsiding.
= 2016
=
By 2016 the mudflow continued with tens of thousands of liters of mud contaminated with heavy metals leaking into rivers.
The site has become of interest to "disaster tourists" who visit the area.
[ By now, payments have been made to about 3,300 households representing 95% of those affected, by the ''Sidoarjo Mudflow Handling Agency'', a government-backed taskforce.][
]
Revived controversy
Out of the three hypotheses on the cause of the Lusi mud volcano, the hydro fracturing hypothesis appeared to be the one most debated. On 23 October 2008 a public relations agency in London, acting for one of the oil well's owners, started to widely publicise what it described as "new facts" on the origin of the mud volcano, which were subsequently presented at an American Association of Petroleum Geologists
The American Association of Petroleum Geologists (AAPG) is one of the world's largest professional geological societies with more than 40,000 members across 129 countries as of 2021. The AAPG works to "advance the science of geology, especially as ...
conference in Cape Town
Cape Town ( af, Kaapstad; , xh, iKapa) is one of South Africa's three capital cities, serving as the seat of the Parliament of South Africa. It is the legislative capital of the country, the oldest city in the country, and the second largest ...
, South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
on 28 October 2008 (see next section). The assertion of the geologists and drillers from Energi Mega Persada was that ''"At a recent Geological Society of London Conference, we provided authoritative new facts that make it absolutely clear that drilling could not have been the trigger of LUSI."'' Other verbal reports of the conference in question indicated that the assertion was by no means accepted uncritically, and that when the novel data is published, it is certain to be scrutinized closely.
In 2009, this well data was finally released and published in the Journal of Marine and Petroleum Geology for the scientific community uses by the geologists and drillers from Energi Mega Persada. It is a common practice in the oil and gas industry to closely guard their drilling and geologic information, and the company involved is no exception. After such release, however, future scientific research on Lusi should have access to a set of credible data and not be as constraint as early authors were with their limited and questionable quality of data to back their claims.
After hearing the (revised) arguments from both sides for the cause of the mud volcano at the American Association of Petroleum Geologists International Convention in Cape Town in October 2008, the vast majority of the conference session audience present (consisting of AAPG oil and gas professionals) voted in favor of the view that the Lusi (Sidoarjo) mudflow had been induced by drilling. On the basis of the arguments presented, 42 out of the 74 scientists came to the conclusion that drilling was entirely responsible, while 13 felt that a combination of drilling and earthquake activity was to blame. Only 3 thought that the earthquake was solely responsible, and 16 geoscientists believed that the evidence was inconclusive.
The report of the debate and its outcomes was published in AAPG Explorer Magazine. The article stated that the voting process was a decision by the moderator and only reflected opinions of a group of individuals in the session room at that time and in no way endorsed by the association. It further cautioned readers not to consider the voting result in any way as a scientific validation.
On the possible trigger of Lusi mud volcano, a group of geologists and drilling engineers from the oil company countered the hydro fracturing hypothesis. They suggested that analysis based on the well data showed that the well was safe and pressure in the well bore was below the critical pressure. It is therefore unlikely that the well was fractured as charged. Their paper also published data and well information for the first time to the scientific communities as opinions and technical papers up to that time lacked accurate well data and were forced to rely on a number of assumptions. However, subsequent studies have refuted the claims made in this paper, and have highlighted that a number of claims made in this study are directly contradicted by the oil company's own well-site reports and documents.
In February 2010, a group led by experts from Britain's Durham University
, mottoeng = Her foundations are upon the holy hills (Psalm 87:1)
, established = (university status)
, type = Public
, academic_staff = 1,830 (2020)
, administrative_staff = 2,640 (2018/19)
, chancellor = Sir Thomas Allen
, vice_chan ...
said the new clues bolstered suspicions the catastrophe was caused by human error. In journal Marine and Petroleum Geology, Professor Richard Davies, of the Centre for Research into Earth Energy Systems (CeREES)
Durham Energy Institute (DEI) is a research institute located within Durham University. It was launched in September 2009 for research in the fields of energy technology and society. The current Executive Director is Professor Jon Gluyas.
The p ...
, said that drillers, looking for gas
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or ...
nearby, had made a series of mistakes. They had overestimated the pressure the well could tolerate, and had not placed protective casing around a section of open well. Then, after failing to find any gas, they hauled the drill
A drill is a tool used for making round holes or driving fasteners. It is fitted with a bit, either a drill or driverchuck. Hand-operated types are dramatically decreasing in popularity and cordless battery-powered ones proliferating due to ...
out while the hole was extremely unstable. By withdrawing the drill, they exposed the wellhole to a "kick" from pressurized
{{Wiktionary
Pressurization or pressurisation is the application of pressure in a given situation or environment.
Industrial
Industrial equipment is often maintained at pressures above or below atmospheric.
Atmospheric
This is the process by ...
water and gas from surrounding rock formation
A rock formation is an isolated, scenic, or spectacular surface rock outcrop. Rock formations are usually the result of weathering and erosion sculpting the existing rock. The term ''rock formation'' can also refer to specific sediment ...
s. The result was a volcano
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most often found where tectonic plates are ...
-like inflow that the drillers tried in vain to stop.
In the same Marine and Petroleum Geology journal, the group of geologists and drilling engineers refuted the allegation showing that the "kick" maximum pressure were too low to fracture the rock formation. The well pressure analysis based on credible data showed that the well is stronger than the maximum pressure exerted on the well. This implied that the hydro fracturing hypothesis is likely to be incorrect. They further stated that the model developed by Prof. Davies is much too simplistic by not considering all the available dataset and information in its analysis.
The 2010 technical paper in this series of debate presents the first balanced overview on the anatomy of the Lusi mud volcanic system with particular emphasis on the critical uncertainties and their influence on the disaster. It showed the differences in the two hypotheses, the source of water and the current understanding on the subsurface geology below the mud volcano. More geological field studies and analysis based on factual data need to be done before any conclusion can be deduced on what actually caused Lusi mud volcano.
In February 2015, Tingay compiled a new and detailed chronology of the drilling of the Banjar Panji-1 well and the first days of the Sidoarjo mudflow. This chronology is built from daily drilling reports and well-site reports and is the first to highlight and document the numerous inconsistencies between papers and reports. The new chronology highlights that a number of key claims made by Lapindo Brantas are contradicted by their own daily drilling and well-site reports (that are included as an appendix in). These include the claims that losses occurred seven minutes after the earthquake (when drilling data actually suggests losses preceded the earthquake); that losses at total depth occurred immediately after major aftershocks (whereas total losses occurred over 1.5 hours after any aftershocks); that losses at total depth were cured (whereas there are multiple reports of ongoing losses over an 18-hour period whilst pulling out of hole); that the drilling kick was killed within 3 hours (whereas drill pipe pressures fluctuate repeatedly for 24 hours after kick, indicating ongoing cycles of downhole influx and losses); that there is no evidence for downhole losses (that would indicate fracturing or fault reactivation) during the drilling kick (yet mud engineer reports state that over 300 barrels of drilling mud was lost downhole during the kick) and; that there was no connection between the mud flow and wellbore (yet the daily drilling reports state that mud flow activity noticeably decreased when dense drilling mud was pumped down the well during attempts to stop the mudflow).
In July 2013, Lupi et al. proposed that the Lusi mud eruption was the result of a natural event, triggered by a distant earthquake at Yogyakarta
Yogyakarta (; jv, ꦔꦪꦺꦴꦒꦾꦏꦂꦠ ; pey, Jogjakarta) is the capital city of Special Region of Yogyakarta in Indonesia, in the south-central part of the island of Java. As the only Indonesian royal city still ruled by a monarchy, ...
two days before. As a result, seismic waves were geometrically focused at the Lusi site leading to mud and CO2 generation and a reactivation of the local Watukosek Fault. According to their hypothesis the fault is linked to a deep hydrothermal system that feeds the eruption. However, this hypothesis has been heavily criticized due to the original models containing a major error. The original study proposed that a “high velocity layer” focussed earthquake waves, amplifying the effect of the earthquake. However, the “high velocity layer” has since been demonstrated to be a non-existent artefact caused by velocity measurements of the steel casing in the Banjar Panji-1 well, which resulted in the original models assuming that a ‘layer of steel’ existed underground. Lupi et al. have acknowledged this error, but argue in a corrigendum that it makes no difference to their results, as they have proposed in a new velocity model, arguing for the existence of a different high velocity layer at the same depth. There still remains significant doubt about this revised model, as another study indicates that there is no geological or geophysical evidence for any significant domed high velocity layer at the mudflow location that would reflect and amplify seismic waves. A study by Rudolph et al. in 2015 replicated the seismic wave propagation modelling at the Sidoarjo mudflow location using the two competing velocity models, and proposed that the modelling conducted by Lupi et al. exaggerates the effect of the Yogyakarta earthquake at the mudflow location.
In June 2015, Tingay et al. used geochemical data recorded during the drilling of the Banjar Panji-1 well to test the hypothesis that the Yogyakarta earthquake triggered liquefaction and fault reactivation at the mudflow location. Liquefaction of the Kalibeng clays is a crucial component of the earthquake-induced fault reactivation hypothesis, as this process releases gases and fluids that cause the pressure changes proposed to induce fault slip. The drilling geochemical data measured gases produced by subsurface rocks in the Banjar Panji-1 in the weeks before the Yogyakarta earthquake and the days afterwards, and provides the first data to directly examine the downhole effects of the earthquake. The data showed no increased release of gases in the days following the Yogyakarta earthquake, indicating that liquefaction and associated gas-related pressure changes were not triggered by the earthquake. The data also shows that gas increases from downhole formations only commenced when the drilling kick occurred, providing further support that the mudflow was triggered by drilling activities.
Gallery
Remenants of Sidoarjo town.JPG, Photo taken of the area of Sidoarjo destroyed by the mud.
School destroyed by mud.jpg, School destroyed by mud flow.
Lake created by mud with steaming mud flow in background.jpg, Lake created by mud with steaming mud flow in background.
Mud hole opening.JPG, Image shows scale of the mud hole, with efforts to contain it by removing the mud and creating embankments for flood defence.
References
External links
Internet Portal for Lapindo's Victim
Bakrie & Brothers homepage
* ttp://www.crisp.nus.edu.sg/coverages/mudflow Satellite imagery and Google Earth kml satellite image overlaysby CRISP/National University of Singapore
The National University of Singapore (NUS) is a national public research university in Singapore. Founded in 1905 as the Straits Settlements and Federated Malay States Government Medical School, NUS is the oldest autonomous university in the c ...
The EGU Newsletters, Issue 19 March 2007: Mud volcano in Java, known locally as 'Lusi' may continue to erupt for months and possibly years. p.5.
Humanitus Sidoarjo Fund – LUSI Research Library
{{DEFAULTSORT:Sidoarjo Mud Flow
Mud volcanoes
Volcanoes of East Java
Volcanoes of Java
Disasters in Indonesia
2006 disasters in Indonesia
2006 in Indonesia
Drilling technology
Geology of Indonesia