Stephanie Ross Soil characteristics of LUSI s mud Feb 12 2008 Soil Characteristics of Mud From the Indonesian Mud Volcano LUSI Stephanie Ross Abstract In Sidoarjo on the island of Java Indonesia a mud volcano nicknamed LUSI has been erupting since May of 2006 Although belated efforts were made to contain the mudflow a region greater than 600 hectares Jakarta AFP 2008 has been completely inundated The mud has become the new substrate of the region so its fertility may influence species recolonization of the area as well as indicate the potential of future land use Since most mud volcanoes are studied for their fluid mosaics and gaseous effluxes no studies have specifically investigated the mud for its nutritive qualities This study establishes a simple fertility index of LUSI s mud by testing for three soil properties that are important for plant growth Carbon to nitrogen ratio C N pH and cation exchange capacity CEC LUSI s C N ratio 12 1 1 01 n 13 fell at the low end of the of corresponding tropical soil data range 10 3 27 Trumbore 1993 LUSI s pH was found to be basic 8 22 0 062 n 13 relative to the range of tropical soil pH 3 9 6 3 Motavalli et al 1995 LUSI s CEC 19 72 cmol kg 1 28 n 12 was high relative to tropical soil CEC 6 55 cmol kg 1 12 n 9 Trumbore 1993 More specifically LUSI s C 1 293 C 0 0448 n 13 and N 0 1076 N 0 0052 n 13 were both very low Motavalli et al 1995 Ewel et al 1991 These values indicate that C and N may need to be fertilized for plant growth because levels are so minimal and buffering for the basic pH may be necessary as well The high CEC levels indicate there are reasonable amounts of nutrient cations present in the mud Together these results indicate that although the mud is not completely infertile but reutilization of the region for agricultural use will probably require a significant amount of modification to the mud p 1 Stephanie Ross Soil characteristics of LUSI s mud Feb 12 2008 Introduction Unique among mud volcanoes is LUSI which erupted May 29th 2006 in Sidoarjo Java Indonesia close to heavily populated regions of the island Davies et al 2007 Still exuding mud it is the largest and longest lasting of reported mud eruptions Mazzini et al 2007 Mud volcanoes usually subside in a few days or weeks Mazzini et al 2007 but LUSI has been erupting for almost 2 years Before leveling to its current 130 000 150 000 m3 day Jakarta AFP 2008 the flow rate peaked at 180 000 m3 day Mazzini et al 2007 an amount equal to 72 Olympic sized swimming pools Moreover the volume of this mud has an unusually high percentage of water 70 which makes it an outlier at the dilute watery end of the mud volcanoes viscosity spectrum Cyranoski et al 2007 An expected percentage would be approximately 20 40 water Hovland et al 1997 given its depth of eruption estimated to be between 1615 1828m Mazzini et al 2007 Furthermore there is heavy subterranean pressure buildup therefore the core eruption column has not clogged allowing for continued mud expulsion Cyranoski et al 2007 The magnitude and length of the eruption has been so great that mud and water have inundated an area of approximately 600 hectares an area equal to 2200 football fields Jakarta AFP 2008 and has displaced over 30 000 people Mazzini et al 2007 This is significant considering only 900 of the 1700 known mud volcanoes are terrestrial Jerosch et al 2007 and none of comparable scale has been documented before Davies et al 2007 Most mud volcanoes are studied during periods of dormancy after they have already been established Mazzini et al 2007 whereas LUSI has been monitored since its origin as a pioneer mud volcano Davies and Stewart 2005 Interestingly this has lead to a heated political and scientific debate as to whether the eruption was catalyzed by drilling operations Cyranoski et al 2007 Davies et al 2007 or by a recent 6 3 magnitude earthquake Mazzini et al 2007 Aside from its unclear origins LUSI does not categorize well into the three typical mudflow types Lokbatan Chikishlyar and Schugin as described by Dimitrov 2002 taken from Kalinko 1964 which are summarized as follows Lokbatan type explosive with flames from ignited gasses and long periods of dormancy well formed cones with high water content Chikishlyar type weak continuous eruption that lacks explosiveness many vents emitting gasses and mud pool like or only very slightly conic Schugin type represents the transitional type of mud volcano weak activity during the periods of eruption predominantly composite craters p 2 Stephanie Ross Soil characteristics of LUSI s mud Feb 12 2008 presumably with minimal mudflow Comparing these characteristics to LUSI s makes it clear that LUSI does not fit in with any of these three classifications Like the Lokbatan type LUSI has high water content but LUSI has had no long periods of dormancy nor is LUSI conic in shape Although LUSI is flat and not conic in shape unlike the Chikishlyar type LUSI is not represented by weak activity nor does it have more than one distinguishable epicenter LUSI has least in common with the Schugin type with neither weak activity nor minimal mudflow Since LUSI does not categorize well into the three established mud volcano types it is plausible that its mud characteristics are also anomalous relative to other mud volcanoes Numerous other mud volcanoes have been studied at the Alaskan Mountains Sorey et al 2005 Azerbaijan Gallagher 2003 the Gulf of Cadiz Hensen et al 2007 Mt Etna Giammanco et al 2007 etc Usually such studies test or monitor gaseous effluxes Giammanco et al 2007 and fluid mosaics Hensen et al 2007 which refers to the variety of fluids oil brine etc that may be present in the mud and their possible origins from underground Despite being new even LUSI has had its gas and water composition extensively analyzed by Mazzini and colleagues 2007 but LUSI s mud composition has not yet been investigated other than for the purpose of determining the depth of its epicenter Mazzini et al 2007 Some trends do emerge from studies of other mud volcanoes that could be seen in LUSI s mud composition such as a basic pH of the mud Ginsburg et al 1999 Kopf 2002 Despite a few potential points of commonality with other mud volcano studies there are few if any mud volcano studies with data relevant to my study The reason for this lack of comparability is because gaseous efflux and fluid mosaic data are measured in units different than those measured in this study this study investigates
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