Gunung Merapi Research Articles

The Economic Benefit of Gunung Merapi National Park for the Welfare of the Buffer Village Community

The Economic Benefit of Gunung Merapi National Park for the Welfare of the Buffer Village Community

Development of Land Cover and Carbon Storage in Plawangan Hill of Gunung Merapi National Park, Yogyakarta, Using Landsat Data Series 2009, 2013, 2017, and 2023

Globally, habitat loss, deforestation, and climate change are mostly caused by land cover changes (LCC). The amount of land covered by trees has had a major impact on global warming and climate change. Increasing the amount of land cover helps to mitigate climate change and global warming. This study aims to investigate the changes in land cover and carbon storage in Plawangan Hill, Indonesia, over four years (2009, 2013, 2017, and 2023). The study site was defined as a conservation area that has been periodically impacted both directly and indirectly by volcanic eruptions. Images from Landsat 7 and 8 were used to collect data. Additionally, land cover changes were assessed using the forest canopy density (FCD Mapper) model, which was then utilized to quantify the carbon storage of the research site. The findings demonstrated fluctuations in land cover changes between 2009 and 2023. Additionally, changes in land cover have a direct impact on changes in carbon storage. The age of the trees, type of vegetation, succession stage, and history of eruptions were the variables that were apparent to be the main causes of these changes.

The characteristic of impacted soil by the Merapi Eruption in Plawangan Hill of Taman Nasional Gunung Merapi, Yogyakarta, Indonesia

Mount Merapi National Park (TNGM) is one of the active volcanos in Indonesia. It has past volcano eruption history since 1911 up to date. Specifically, Plawangan Hill is a part of the TNGM recently designated as Geo-heritage and has experienced volcano eruption indirectly and directly. Additionally, since the Indonesian government designates Plawangan Hill as a Geological Heritage (Geo-Heritage) location, it is crucial to determine its geological features and how they relate to the development of the vegetation there as the study’s objectives. A field survey and a soil laboratory examination were conducted to obtain the data. As a result, Plawangan Hill’s DEM was classified from very low to very high classes, while the DSM was categorized from flat to very steep slopes. Further, the results demonstrated that the pH of the soil was typically somewhat acidic (5.93–6.54). While the soil’s nitrogen content was found to be low to medium, both phosphorus and potassium levels were typically very low. The carbon-nitrogen ratio was generally categorized into the medium, while the organic C ranged from low to medium (1.44% to 3.22%). The soil’s N total, K total, organic matter, carbon content, and C-N ratio increased by the erupted material age. Additionally, it was discovered that the vegetation growth was excellent in indirect (IA) and directly affected (DA) conditions, as indicated by their diameter at breast height (Dbh) and height (H). The correlation between soil characteristics and vegetation growth differed in indirectly affected (IA) and directly affected (DA) areas. As a result, the study found that volcanic materials significantly contributed to Plawangan Hill’s soil characteristics and vegetation growth. Furthermore, this study’s findings were highly beneficial because they were one of the primary explanations for why Plawangan Hill was designated a Geo-heritage site.

The Vernacular of Disaster: The Rhetoric and Memory of Volcanic Eruption at Museum Gunung Merapi, Indonesia

This study analyzes the vernacular rhetoric of disaster in a volcanic eruption museum. Using the Mount Merapi Museum (Museum Gunung Merapi or MGM) in Indonesia, the research investigates how the site has become a public memorial for volcanic disasters through archival work, textual analysis, and in-the-field methods. The findings show that MGM materializes a “vernacular rhetoric of disaster” through the socio-cultural aspect. It emphasizes the juxtaposition of mythological stories, scientific descriptions, and everyday discourses produced by the disasters, centering on the philosophy of eling or the act of remembering in Javanese society. Finally, the paper offers observational frameworks to understand the museum. Those are the situational setting of the museum's location culturally and socially, the building design, and the connection of everyday life to the surrounding contexts. This framework is helpful to be applied in another setting.

Gendhing Sekaten. (2010) 2020Gendhing Pahargyan. (2012) 2020Gendhing Kurmat Dalem. 2020Gendhing Gati. (2015) 2020Gendhing Gati Volume 2. 2020Gendhing Soran Volume 1. 2021

Gendhing Sekaten. (2010) 2020Gendhing Pahargyan. (2012) 2020Gendhing Kurmat Dalem. 2020Gendhing Gati. (2015) 2020Gendhing Gati Volume 2. 2020Gendhing Soran Volume 1. 2021

Response of terrestrial mammals to various types of disturbance in the Gunung Merapi National Park, Indonesia

Abstract. Sulaksono N, Pudyatmoko S, Soemardi, Wardhana W, Hadiyan Y, Nurvianto S. 2022. Response of terrestrial mammals to various types of disturbance in the Gunung Merapi National Park, Indonesia. Biodiversitas 23: 1635-1647. Human disturbance in the form of sand mining and grass harvesting activities in the area of Mount Merapi is an important component of the ecological process alongside the eruption. The group of terrestrial mammals (TM) is one of the essential elements that are affected by this disturbance. Therefore, the objectives of this study were to determine the response of the TM in various types of habitats in areas affected by eruption disturbances >20 years (ERL), eruption < 20 years (ERE), mining (MIN), grazing (GRA), and non-disturbance areas (NDA) in Gunung Merapi National Park (GMNP). Camera traps were used to identify the abundance of each TM. Vegetation data were also used to represent habitat conditions and were taken on a plot of 0.04 Ha. The analysis results showed that the highest abundance of TM is at the NDA site (14.4), while the lowest is at the MIN site (2.08). The site with the highest level of TM diversity is ERL (1.97) and the lowest is NDA (1.52). Furthermore, there is a significant difference in TM abundance between the MIN and ERL sites, which indicates that each disturbance reacts differently to the site. Based on the results, mining disturbances negatively influenced the abundance of TM in GMNP, therefore, managers need to regulate mining activities and make efforts to restore the affected areas.

Sistem Komunikasi Radio Terpadu Masyarakat Mitra Polhut dan Masyarakat Peduli Api di Kawasan Gunung Merapi

Abstract Purpose: to find out the Integrated Radio Communication System potential volunteers from the community who are members of the MPP and MPA to increase their understanding of mastery of radio communication tools, ethics, and coded communication and to follow the frequency regulations set by the Ministry of Communications and Information Technology. Methode: The community service method uses an Integrated Radio Communication System workshop and training for people who are members of the MPP and MPA on how to set up radio communication tools, using two-meter band radio communication procedures, communication ethics, and mastery of communication languages. Result: Design and installation of radio repeater Integrated Radio Communication System Workshop resulted in an understanding of the SKRT system and improved MPP and MPA capabilities. Mastery of communication tools, ethics, communication code language, and following frequency regulations set by the government. Limitations: By planning and implementing the SKRT and preparing volunteers from the community, MPP and MPA will support the main tasks and functions of the Taman Nasional Gunung Merapi for the protection and security and handling of the Mount Merapi eruption disaster. Research Contribution: Carrying out the implementation, in this case, is the Taman Nasional Gunung Merapi to plan and implement the SKRT and prepare the potential of the community to take joint responsibility for the conservation, protection, and security, and disaster response of Mount Merapi.

Cover, Content, and Editorial Note from Borneo J Pharm Vol. 4 No. 3 August 2021

Assalamu’alaikum Wr. Wb.
 Alhamdulillahirabbil ‘alamin. The next edition of Borneo Journal of Pharmacy (Borneo J Pharm), has been published in August 2021. Starting from this volume, Borneo J Pharm increases the frequency of publishing four times a year. This change aims to improve the circulation of the best articles published by Borneo J Pharm.
 This edition contains ten articles consisting of Pharmacology-Toxicology, Microbiology Pharmacy, Natural Product Development, Clinical-Community Pharmacy, and Management Pharmacy. This edition includes writings from four countries including Greece, Indonesia, Saudi Arabia, and Sudan. The authors come from several institutions, including STIKES Cendekia Utama Kudus, Universitas Sari Mulia, National Agency of Drug and Food Control of Republic of Indonesia, National Agency of Drug and Food Control of Republic of Indonesia in Gorontalo, Universitas Muhammadiyah Kalimantan Timur, Balai Taman Nasional Gunung Merapi, Universitas Sembilanbelas November Kolaka, Sekolah Tinggi Ilmu Farmasi Riau, Omdurman Islamic University, University of Khartoum, King Saud University, Indonesian Institute of Sciences, Universitas Pancasila, Universitas Lambung Mangkurat, Universitas Jenderal Achmad Yani, Ibrahim Adjie Health Center, University of Crete, Aristotle University of Thessaloniki, New York College, Universitas Islam Sultan Agung, Sekolah Tinggi Ilmu Kesehatan Borneo Lestari, and Universitas Muhammadiyah Surakarta.
 The editorial board would like to thank all editors and reviewers, and contributors of the scientific articles who have provided the repertoire in this issue. We hope that all parties, especially the contributors, could re-participate for publication in the next edition in November 2021.
 Wassalamu’alaikum Wr. Wb.

Principal-Agent Relation in Conserving the Kali Putih Area in the Reconstruction and Mitigation Zone of Merapi Mountain National Park

This article aims to observe the dynamics of policy implementation involving various stakeholders in the effort of conserving one of the National Parks in Indonesia, particularly Merapi Mountain National Park (Taman Nasional Gunung Merapi – TNGM). Following the Zoning Policy implemented in the TNGM area, there is a zone that should have been protected from mining activities, namely the reconstruction and mitigation zone. However, in its implementation, the conservation collaboration agreement of one of the areas in the zone, namely the Kali Putih Area, is instead used by some parties to engage in sand mining activities. The principal-agent theory is, thus, employed in this study to examine the extent of the relationship of every party in the zoning policy implementation process of an area designated as a Reconstruction and Mitigation Zone. The qualitative approach is used to gain direct insights pertaining to the implementation of efforts conducted by several relevant parties in conserving the Kali Putih Area in TNGM’s Reconstruction and Mitigation Zone. Study results ultimately show that moral hazard in the principal-agent theory should not only be understood as deviant behaviors enacted by the agent, but the moral hazard performed by the agent may also inϐluence the principal’s decision making process. This research is expected to provide an outlook to the government, which functions as the principal in a policy, to make several considerations prior to entering into any collaborative agreement or making any decision, so that the implementation process of policies can align with what has been previously planned.

Direct economic benefits and human dependence toward Gunung Merapi National Park, Indonesia

Abstract. Umaya R, Hardjanto, Soekmadi R, Sunito S. 2020. Direct economic benefits and human dependence toward Gunung Merapi National Park, Indonesia. Biodiversitas 21: 982-993. Merapi (Java, Indonesia) is recognized as the most active volcano in Indonesia. This area has also gazetted as a national park, called Gunung Merapi National Park (GNMP), despite the existence of humans who live adjacent to the park with high dependency on its resources. The objectives of this study were to determine direct use value (DUV) and investigate human dependence toward the goods and services generated from GNMP. The research was conducted in 27 sub-villages. In total 277 respondents and 62 key informants were selected using purposive sampling and 9 times focus group discussion. The DUV was estimated using market price approach. The results of this study found that the DUV of GMNP was IDR 87,947,589,505 year-1, generated from direct benefit of grasses for animal feedstock (41.74%), sand mining (31.32%), water consumption (20.23%), fuelwood collection (3.57%), ecotourism activities (1.65%), land management for agriculture (1.48%), and orchid conservation program (0.01%). The dominance of DUV derived from grasses collection, sand mining and water consumption was highly correlated with the characteristics of sub-villages communities, influenced by the events of eruption of Merapi volcano, changes in legal status of forest function and market situations. Sub-village communities have historically developed reciprocal relationships with Merapi volcano and its surrounding ecosystem in terms of ecological, economic, and cultural aspects, and they played important roles in natural resources management of Merapi volcano. The findings of this study suggest that an important strategy for GMNP authority is by positioning sub-village communities and their norms as resource beneficiaries and partners in managing the park, highlighting that their existence should not be neglected.

Participatory Communication in Children Empowerment Program in Yogyakarta: The Case of Sekolah Gunung Merapi and Komunitas Jendela Jogja

Using qualitative approach, this study aims to analyse the participatory communication in the children empowerment programs held by Sekolah Gunung Merapi and Komunitas Jendela Jogja, as well as its supporting and undermining factors. The data of this study were collected through in-depth interviews, semi-participant observations, and document collections. Six informants were involved in this study, which were purposively selected as they are activists of the two research communities. As a result, the study shows that participation in children empowerment programs in Yogyakarta appears at four processes: decision-making, activities implementation, monitoring and evaluation and outcome utility. In each process, they mostly use the concept of dialogue and carnival participation. In terms of participation level, the children empowerment programs held by Sekolah Gunung Merapi and Komunitas Jendela Jogja are both in partnership level with roles as accelerator, mediator, educator, expert and social planner. The supporting factors in the children empowerment programs include supports and facilities while the undermining factors are the lacks of number and teaching skill from volunteer’s side and troubles from student’s side.Keywords: Children empowerment program; participation; participatory communication; Sekolah Gunung Merapi; Komunitas Jendela Jogja.

Mitigation & Identification for Local Aridity, Based of Vegetation Indices Combined with Spatial Statistics & Clustering K Means

This research aims to develop new methods of mapping aridity risk zones and their potential impacts on land fires using a combination of indices to identify land fires such as the CSI and NBR and the indices for NDVI and SAVI. The research location is in Gunung Merapi National Park (TNGM) and Gunung Merbabu National Park (TNGMb), in Central Java Province and Yogyakarta. The data used in this research is Landsat 8 OLI image year 2010-2018, DEM data from ASTER image in TNGM and TNGMb area using landsat 8 OLI image specification. The research was conducted in 3 stages such as pre-processing, image data extraction and post-processing. Global and Local Moran’s Analysis on NDVI, SAVI, CSI and NBR vegetation indices data can be used as an indicator of aridity and potential land fires. The experiments show that the average is in class 4 including the moderate greenish classification. Moderate greenish is interpreted that the study area is overgrown with meadows, shrubs, barren, sandy, rocky areas and a low population of vegetation canopy that shows that the area is on the surrounding mountain peaks. The results of the analysis shows Positive Spatial Autocorrelation, the phenomenon of aridity has spatial connectivity between observed regions. Analysis of K Means on the high vegetation density conditions shows that the weight of the distance between the vegetation data to the centroid is shorter, therefore the data is concentrated on a region. In low vegetation density conditions, the weight of the distance between the data to the centroid is increasingly wide, therefore the data looks more widely distributed.

Fern Diversity in Taman Nasional Gunung Merapi and Its Potency as a Biology Learning Resource

In the kingdom of Plantae, fern (Pteridophyte) is one of the largest and diverse plant group. They are dominant on the forest floor in warm temperatures and high humidity. This research aims: (1) to present the diversity of fern in Taman Nasional Gunung Merapi (TNGM), (2) to analyze the potency of fern diversity in TNGM as biological learning resources and (3) the feasibility of Pteridophyte Photo Sequence as learning media. The research was carried out through observation for identifying anykinds of fern and analyzing the potency of fern diversity as a learning resource, especially to study the Pteridophyte. In order to develop media photo sequence, this research used the ADDIE model (Analysis, Design, Development, Implementation, and Evaluation), but it was limited to the step of Development. The result showed that seventy five species of fern have been found in TNGM which is included in the 3 of 4 classes i.e. Lycopsida (8 species), Equisetopsida (1 species), and Pteropsida (66 species). It could be used as learning resource on subtopic of Pteridophyte for high school students in 10th grade based on Biology Curriculum 2013. The feasibility value for media photo sequence of pteridophyte in TNGM showed “very good” category.

Presenting Local Wisdom: A Multimodal Analysis of Sedekah Gunung Merapi Video as a Tourism Promotion in Boyolali Regency

Upacara tradisional Sedekah Gunung adalah salah satu kearifan lokal yang dimiliki oleh masyarakat Desa Lencoh, Selo, Kabupaten Boyolali. Upacara ini bertujuan untuk mengungkapkan rasa terima kasih penduduk desa dan meminta perlindungan Tuhan dari bencana. Upacara ini memiliki potensi karena sering menjadi daya tarik wisata. Liputan media diperlukan untuk menyebarkan konten dan informasi tentang upacara ini. Salah satu contoh liputan media tentang tradisi ini adalah video yang diunggah di situs berbagi video YouTube bernama Sedekah Gunung merapi. Tulisan ini menganalisis beberapa aspek: (1) Apa sarana yang digunakan dalam video Sedekah Gunung Merapi untuk menghadirkan Sedekah Gunung sebagai objek wisata Kabupaten Boyolali? (2) Bagaimana penyajian kearifan lokal Boyolali dalam video Sedekah Gunung Merapi mempromosikan pariwisata Kabupaten Boyolali? (3) Apa makna penyajian kearifan lokal dalam video Sedekah Gunung merapi sebagai promosi pariwisata di Kabupaten Boyolali? Metode yang digunakan dalam penelitian ini adalah nalisis multimodal yang dikembangkan oleh Kress dan van Leeuwen. Video yang diteliti mengandung lebih dari dua sistem semiotik yang terdiri dari linguistik, visual, audio, gestural, dan spasial. Penelitian ini menemukan bahwa wacana tentang kearifan lokal dibangun untuk menonjolkan kekayaan budaya yang dimiliki oleh komunitas Boyolali. Wacana dikemas dan disebarluaskan melalui video untuk mengkomersialkan pariwisata kabupaten Boyolali. The traditional ceremony of Sedekah Gunung is one of the local wisdoms possessed by the community of Lencoh Village, Selo, Boyolali Regency. The ceremony aims to express the villagers’ gratitude and requests the protection of God from disasters. This ceremony has potency as it often becomes a tourist attraction. media coverages are needed to disseminate contents and information about this ceremony. one example of existing media coverages on the tradition is a video uploaded on video-sharing website YouTube named Sedekah Gunung Merapi. This paper analyzes several aspects: (1) What are the means used in the Sedekah Gunung Merapi video to present Sedekah Gunung as a tourist attraction of Boyolali Regency? (2) How does the presentation of Boyolali’s local wisdom in Sedekah Gunung merapi video promotes Boyolali Regency’s tourism? (3) What is the meaning of presenting local wisdom in Sedekah Gunung Merapi video as tourism promotion in Boyolali Regency? The method used in this research is multimodal analysis developed by Kress and van Leeuwen. The studied video contains more than two semiotic systems consisting of linguistic, visual, audio, gestural, and spatial. The research finds that discourses on local wisdom are constructed to accentuate the cultural richness possessed by Boyolali’s community. discourses are packaged and disseminated through the video to commercialize the regency’s tourism.

RETRACTED: Peran modal sosial dalam penanganan bencana pada masyarakat desa rawan bencana Gunung Merapi

Following a rigorous and careful concerns and consideration in the review of the article published in JPPM (Jurnal Pendidikan dan Pemberdayaan Masyarakat) entitled “Peran modal sosial dalam penanganan bencana pada masyarakat desa rawan bencana Gunung Merapi” Vol 5, No 2, pp. 128-141, November 2018, DOI: http://dx.doi.org/10.21831/jppm.v5i2.21787This paper has been found to violate the principles of Jurnal Inovasi Pendidikan IPA Publication and has been retracted.The article has been drawn by the author and will be published in the Jurnal Cakrawala Pendidikan https://journal.uny.ac.id/index.php/cpThe document and its content have been removed from Jurnal Inovasi Pendidikan IPA, and reasonable effort should be made to remove all references to this article.

AN ANALYSIS OF THE STRATEGIES USED IN TRANSLATING IDIOMS IN INDONESIA INTO ENGLISH FOUND IN INDONESIAN LEGENDS

In this global era, due to the growth of science, information, technology, and other people needs, translation becomes necessary in rendering information between languages. However, the process of translating is not as simple as switching the meaning of word for word based on the literal context.Idioms are one of the most problematical components of language. Idioms cannot be easily translated because of their unpredictable meaning and grammar. The purpose of this study is to find out; (1) the idiomatic expressions which are found in Indonesian Legends, (2) the meaning of the idiomatic expressions found in Indonesian Legends, and (3) the various strategies which are used in translating idioms in Indonesia into English found in Indonesian Legends.The descriptive qualitative research design, in the form of document analysis, was employed in this study. The instruments to collect the data were documents and expert opinion. Moreover, the documents consisted of the Bahasa Indonesia (Source Text) and English (Target Text) translation versions of five Indonesian Legends, namely; Batu Kuwung, Batu Menangis, Gunung Merapi, Tangkuban Perahu and Candi Prambanan. This study revealed that idiomatic expression translation strategy by paraphrasingwas the most dominant strategy used by the translator in translating the idiomatic expressions found in five Indonesian Legends (eleven out of eighteen cases). Meanwhile, the second most common strategy was translating by omission (six out of eighteen cases). The last was the strategy of using an idiom of similar meaning and form which only one out of eighteen cases. Thus, it can be concluded that the translator only applied three strategies out of the main five strategies of translating idiomatic expression suggested by Baker.

AN ANALYSIS OF THE STRATEGIES USED IN TRANSLATING IDIOMS IN INDONESIA INTO ENGLISH FOUND IN INDONESIAN LEGENDS

In this global era, due to the growth of science, information, technology, and other people needs, translation becomes necessary in rendering information between languages. However, the process of translating is not as simple as switching the meaning of word for word based on the literal context.Idioms are one of the most problematical components of language. Idioms cannot be easily translated because of their unpredictable meaning and grammar. The purpose of this study is to find out; (1) the idiomatic expressions which are found in Indonesian Legends, (2) the meaning of the idiomatic expressions found in Indonesian Legends, and (3) the various strategies which are used in translating idioms in Indonesia into English found in Indonesian Legends.The descriptive qualitative research design, in the form of document analysis, was employed in this study. The instruments to collect the data were documents and expert opinion. Moreover, the documents consisted of the Bahasa Indonesia (Source Text) and English (Target Text) translation versions of five Indonesian Legends, namely; Batu Kuwung, Batu Menangis, Gunung Merapi, Tangkuban Perahu and Candi Prambanan. This study revealed that idiomatic expression translation strategy by paraphrasingwas the most dominant strategy used by the translator in translating the idiomatic expressions found in five Indonesian Legends (eleven out of eighteen cases). Meanwhile, the second most common strategy was translating by omission (six out of eighteen cases). The last was the strategy of using an idiom of similar meaning and form which only one out of eighteen cases. Thus, it can be concluded that the translator only applied three strategies out of the main five strategies of translating idiomatic expression suggested by Baker.

KERAGAMAN GENETIK DAN PERMUDAAN ALAM PUSPA (Schima wallichii (DC.) Korth.) DI TAMAN NASIONAL GUNUNG MERAPI PASCAERUPSI TAHUN 2010

Schima wallichii (DC.) Korth. (puspa) is a native vegetation of Gunung Merapi National Park (GMNP). This species has an important function for soil and water conservation in GMNP area, especially in the area with high slope. Puspa is also one of prioritised species planted in the forest ecosystem restoration project of GMNP after 2010 volcano eruption. Information on genetic diversity and natural regeneration potential of each puspa stand groups is then very essential for the success of forest ecosystem restoration in GMNP. Genetic diversity parameters of puspa is assessed by isozyme analysis, while its natural regeneration is evaluated by vegetation analysis. Selection of samples on stand groups of puspa for genetic diversity and natural regeneration analysis is based on levels of vegetation damage (low and moderate) and the planting plots of ecosystem restoration area. The results showed that the stands with low damage level located at Gunung Malang and Mriyan have higher genetic diversity than those with moderate damage level (Balerante and Tlogolele). Stand with the highest genetic diversity is Gunung Malang, with the mean observed heterozigosities (Ho) of 0.284 and minimum fixation index value (FIS) of 0.0508. Stand in the Ecosystem Restoration Demonstration Plot has the lowest level of genetic diversity (Ho = 0.1936; FIS = 0.1127). Regarding natural regeneration potential, the stand group of Gunung Malang is the highest.

Effects of volatile behaviour on dome collapse and resultant pyroclastic surge dynamics: Gunung Merapi 2010 eruption

Abstract In 2010, Gunung Merapi (Central Java, Indonesia) generated two violent eruption sequences on 26 October and 5 November culminating in widespread pyroclastic density currents (PDCs) associated with the destruction of lava domes. Tephra from PDC deposits were analysed to examine pre-dome collapse volatile behaviour and evidence of carbonate assimilation. Secondary-ion mass spectroscopy (SIMS) depth profiles of plagioclase phenocrysts reveal that the 7 Li/ 30 Si ratios in 26 October products are higher in the glass compared to the crystal, indicating a build-up of Li in the groundmass not observed in the 5 November samples. Higher Li in the groundmass suggests gas accumulation and rapid development of conduit overpressure in the shallow plumbing system prior to the initial 26 October explosion, which was only captured through the behaviour of quickly diffusing Li and not H 2 O. Following the explosion-induced decompression, juvenile magma rapidly ascended in great volume to generate extremely destructive PDCs following subsequent dome collapses, particularly on 5 November. Additionally, 26 October tephras contain carbonate grains in the ash component and abundant CO 2 within the lava lapilli groundmass glass, which supports previous studies indicating assimilation of calc-silicate lithologies by the Merapi magma at depth in the plumbing system prior to the onset of 2010 activity. supplementary material: Feldspar microlite compositions and SIMS volatile data for the glass measurements are available at http://www.geolsoc.org.uk/SUP18762 .

Fluid ascent and magma storage beneath Gunung Merapi revealed by multi-scale seismic imaging

Magma is fed to a volcano through a complex “plumbing” system that involves not only shallow structures beneath the volcano edifice, but also deep structures and processes within the underlying crust and upper mantle. This paper summarizes seismic experiments carried out over many years at Gunung Merapi in Central Java. These have resolved the 3D seismic velocity structure of the Merapi edifice, and provided a 3D structural image of the lithosphere and subduction zone beneath Central Java. Earthquake locations reveal that with distance from the trench, the dip of the subducting slab steepens from nearly horizontal (0–150km), through 45° (150–250km), to 70° (>250km). The slab appears as a 30km thick double layer of seismicity in a depth range of 80km to 150km, and it can be identified seismically to a depth of more than 600km. The active volcanoes of Merapi, Sumbing, and Lawu are located at the edge of a large low velocity body that extends from the upper crust to the upper mantle beneath Central Java. Shear wave signals recorded above this anomaly are strongly attenuated compared to neighboring areas. The anomalous body has a detected volume of >50,000km3 and a decrease in P and S velocities relative to adjacent regions of up to 30%. The resulting Vp/Vs ratio of up to 1.9 is unusually high for lower crust. Additionally, the anomaly extends along a 45 degree-slope downward from beneath the volcanic arc and meets the slab at 100km depth. We interpret this sloping anomaly as a pathway for fluids and partial melts. Increased seismicity is observed at depths of ~100km, possibly as a result of dehydration of the subducting slab with related fluid releases causing partial melting of overlying mantle material. The large velocity reduction and high Vp/Vs ratio in the region are consistent with an increase in temperature, a reduction of shear strength, and the presence of fluids or melts of 13 to 25vol.%. The detected strong anomaly beneath Central Java is unique in size and amplitude compared to other subduction zones. The geophysical evidence suggests that this segment of the arc has a high magma flux and is thus capable of developing even larger shallow crustal reservoirs and more voluminous explosive eruptions in the future.