Research

Understanding earthquakes with physics and AI

My work combines numerical simulation, machine learning and observational seismology to understand earthquake processes and turn seismic data into useful information, as part of the Computational Seismology Research Group.

Current project

Real-time monitoring & automatic AI processing

I am building a real-time seismic monitoring system with AI-based automatic processing in collaboration with Pertamina Geothermal Energy and Pemerintah Kota Surabaya.

Real-time seismic data acquisition
AI-assisted automatic event detection and processing
Partners: Pertamina Geothermal Energy, Pemerintah Kota Surabaya

Focus areas

Research interests

Earthquake rupture dynamics

3D dynamic rupture simulations on complex fault geometries and fracture networks.

Induced seismicity

Seismicity from geothermal and subsurface operations, and how it differs from natural earthquakes.

Deep learning in seismology

Denoising, detection and generative models for seismic waveforms.

Distributed Acoustic Sensing (DAS)

Fibre-optic seismic sensing, including the ITS fibre network, for dense-array earthquake monitoring and subsurface studies.

Earthquake source mechanics

Source parameters, stress fields and fault behaviour in Indonesia and beyond.

Fault & seismic hazard

Fault characterisation, stress mapping and earthquake scenarios for seismic hazard assessment in Indonesia.

Projects

Current research projects

Ongoing work across Indonesia, from AI-driven monitoring and fibre-optic sensing to earthquake source studies and subsurface imaging.

Monitoring, sensing & AI

AI agent for real-time earthquake monitoring in geothermal areas

An AI agent that supports real-time earthquake monitoring in geothermal fields, automating detection, processing and reporting of seismic events.

Distributed Acoustic Sensing on the ITS fibre network

Using the existing fibre-optic network at ITS as a dense seismic array with Distributed Acoustic Sensing (DAS).

Bromo seismicity

Seismicity of Mount Bromo, an active volcano in East Java.

Earthquake studies across Indonesia

Flores earthquakes

Earthquakes in the Flores region of East Nusa Tenggara: their sources and the faults that host them.

Halmahera earthquake

The Halmahera earthquake in North Maluku: its source and fault structure.

Poso earthquake

The Poso earthquake in Central Sulawesi: its source and fault structure.

Tarakan earthquake

The Tarakan earthquake in North Kalimantan: its source and fault structure.

Subsurface structure imaging

Dieng subsurface structure

Imaging the structure beneath the Dieng volcanic and geothermal complex in Central Java using receiver functions and joint inversion with surface waves.

Receiver functions from Bali to Timor

A receiver-function study of the crust and upper mantle along the Lesser Sunda Islands, from Bali to Timor.

Stress & seismic hazard

High-resolution spatial stress ratio and principal stress orientation in the Java region

We determine stress ratios and principal stress orientations across Java using open earthquake source-mechanism data from national and international agencies and published studies. Poorly constrained source mechanisms are re-evaluated with stochastic Bayesian moment tensor inversion, and stress is inverted with the open-source STRESSINVERSE software. The result is a public online platform with an interactive map of stress ratios and principal stress orientations, backed by a database that approved users can contribute to.

Project website West Java paper

Publications

Recent publications

Selected work from 2024 to 2026. Full lists on Google Scholar and SINTA.

Google Scholar SINTA

2026

Hydraulic stimulation experiments attempting to enhance induced seismicity for earthquake physics research

Gischig, V.S., Meier, M.A., Lambiase, A., Jiang, D., Hertrich, M., et al. (51 authors, incl. Palgunadi, K.H.)

Journal of Geophysical Research: Solid Earth, 131(7), e2026JB033768

DOI

Shear-wave anisotropy in the 2022 Mw 5.6 Cianjur earthquake area, Indonesia

Ry, R.V., Nugraha, A.D., Muttaqy, F., Zulfakriza, Z., Palgunadi, K.H., Kusumawati, D., Lesmana, A., Putra, A.S., Puspito, N.T. and Fatkhan, F.

Natural Hazards, 122(9), 389

DOI

Analysis of stress ratio and stress regime in West Java

Sirait, A.M., Palgunadi, K.H., Simanjuntak, A.V.H., Rahmania, N., Naufal, I., Dhiarofa, M.N.R., Karimah, A., Al-Ghifari, R.S., Ramadhani, A., Hady, F.H., Warnana, D.D. and Suryanto, W.

Indonesian Journal on Geoscience, 13(1), 43–55

DOI Stress map

Activating a natural fault zone in the Swiss Alps

Meier, M.A., Selvadurai, P., Gischig, V., Hertrich, M., Tinti, E., et al. (80 authors, incl. Palgunadi, K.H.)

Seismica, 5(1)

Article DOI

Evidence of a new backthrust fault system from the 2022 southeast Java, Indonesia earthquake sequence: insights from seismological analysis

Simanjuntak, A.V., Palgunadi, K.H., Syaifuddin, F., Muksin, U., Riama, N.F., Sirait, A.M., Setiadi, T.A., Kusumawati, D., Sahara, D.P., Anshori, M., Triahadini, A., Suryanto, W., Sulandari, B., Saleh, H.M., Iskandar, Y., Ahmadiyah, A.S. and Warnana, D.D.

Journal of Asian Earth Sciences, 295, 106845

DOI

Do 3D dynamic rupture models capture the variability in long-period velocity pulses? Insights from the 2023 Mw 7.8 Kahramanmaraş earthquake

Preca Trapani, R., Marchandon, M., Palgunadi, K.H., Wu, B., Yen, M.H., Cotton, F. and Gabriel, A.A.

EarthArXiv preprint

DOI

2025

High resolution seismic waveform generation using denoising diffusion

Palgunadi, K.H., Bergmeister, A., Bosisio, A., Ermert, L.A., Koroni, M., Perraudin, N., Dirmeier, S. and Meier, M.A.

Journal of Geophysical Research: Machine Learning and Computation, 2(4), e2025JH000862

Code DOI

Crowdsource, crawl, or generate? Creating SEA-VL, a multicultural vision-language dataset for Southeast Asia

Cahyawijaya, S., et al. (99 authors, incl. Palgunadi, K.H.)

Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (ACL 2025), Vol. 1, 18685–18717

PDF DOI

Ground-motion characteristics of cascading earthquakes in a multiscale fracture network

Palgunadi, K.H., Gabriel, A.A., Garagash, D.I., Ulrich, T., Schliwa, N. and Mai, P.M.

Bulletin of the Seismological Society of America, 115(5), 2313–2335

Code SeisSol DOI

Rupture dynamics and velocity structure effects on ground motion during the 2023 Türkiye earthquake doublet

Li, B., Palgunadi, K.H., Wu, B., Suhendi, C., Zhou, Y., Ghosh, A. and Mai, P.M.

Communications Earth & Environment, 6(1), 228

PDF Code SeisSol DOI

Geometrically complex, relatively weak, and subcritically stressed Lembang Fault may lead to a magnitude 7.0 earthquake

Palgunadi, K.H., Simanjuntak, A.V.H., Ry, R.V., Daryono, M.R., Widiyantoro, S., Warnana, D.D., Triahandini, A., Syaifuddin, F., Ahmadiyah, A.S., Sirait, A.M.M. and Suryanto, W.

Journal of Engineering and Technological Sciences, 57(1), 129–144

PDF SeisSol DOI

2024

The western extension of the Balantak Fault revealed by the 2021 earthquake cascade in the central arm of Sulawesi, Indonesia

Simanjuntak, A.V., Palgunadi, K.H., Supendi, P., Muksin, U., Gunawan, E., Widiyantoro, S., Rawlinson, N., Daryono, M.R., Daryono, D., Karnawati, D. and Hanifa, N.R.

Geoscience Letters, 11(1), 35

PDF DOI

Fault size–dependent fracture energy explains multiscale seismicity and cascading earthquakes

Gabriel, A.A., Garagash, D.I., Palgunadi, K.H. and Mai, P.M.

Science, 385(6707), eadj9587

PDF Code SeisSol DOI

Seismic source analysis of the destructive earthquake November 21, 2022, Mw 5.6 Cianjur (Indonesia) from relocated aftershock

Zulfakriza, Z., Nugraha, A.D., Heryandoko, N., Ry, R.V., Muttaqy, F., Andika, A., Azhari, M.F., Putra, A.S., Palgunadi, K.H., Cummins, P.R. and Supendi, P.

Scientific Reports, 14(1), 12142

PDF DOI

Rupture dynamics of cascading earthquakes in a multiscale fracture network

Palgunadi, K.H., Gabriel, A.A., Garagash, D.I., Ulrich, T. and Mai, P.M.

Journal of Geophysical Research: Solid Earth, 129(3), e2023JB027578

PDF Code SeisSol DOI

$Graphical abstract showing multiscale fracture network and cascading earthquakes$

Fault-damage zones comprise multiscale fracture networks that may slip dynamically and interact with the main fault during earthquake rupture. Using 3D dynamic rupture simulations and scale-dependent fracture energy, we examine dynamic interactions of more than 800 intersecting multiscale fractures surrounding a listric fault, emulating a major listric fault and its damage zone. We investigate 10 distinct orientations of maximum horizontal stress, probing the conditions necessary for sustained slip within the fracture network or activating the main fault. Additionally, we assess the feasibility of nucleating dynamic rupture earthquake cascades from a distant fracture and investigate the sensitivity of fracture network cascading rupture to the effective normal stress level. We model either pure cascades or main fault rupture with limited off-fault slip. We find that cascading ruptures within the fracture network are dynamically feasible under certain conditions, including: (a) the fracture energy scales with fracture and fault size, (b) favorable relative pre-stress of fractures within the ambient stress field, and (c) close proximity of fractures. We find that cascading rupture within the fracture network discourages rupture on the main fault. Our simulations suggest that fractures with favorable relative pre-stress, embedded within a fault damage zone, may lead to cascading earthquake rupture that shadows main fault slip. We find that such off-fault events may reach moment magnitudes up to Mw ≈ 5.5, comparable to magnitudes that can be otherwise hosted by the main fault. Our findings offer insights into physical processes governing cascading earthquake dynamic rupture within multiscale fracture networks.