Palu-Koro Fault Research Articles

Neotectonics of the eastern Matano fault, Sulawesi, Indonesia: Preliminary results

The Matano fault in central Sulawesi is one of the major strike-slip faults that accommodate the rapid left-lateral slip between the Pacific and Australian plates. The Matano fault has a high seismic potential of producing large (Mw ≥7) earthquakes. However, the Matano fault was less studied, unlike the Palu-Koro fault. This paper presents preliminary results of our active fault investigation in the eastern Matano fault which may help in understanding the neotectonics and earthquake hazard in central Sulawesi. The late Quaternary deformation of the eastern Matano fault is evidenced by deformed young geomorphic surfaces. The fault shows predominantly left-lateral motion and has steeply dipping fault plane. The eastern portion of the Matano fault may form a seismic gap that potentially host the next surface-rupturing earthquake.

Investigation of Geological Structure Using Magnetotelluric and Gravity Data Optimization on Non Volcanic Geothermal, Bora, Centre of Sulawesi

The existence of geological structures is one of the important parameters in determining the permeability zone in a geothermal system. This research was conducted in a non-volcanic geothermal field, Bora, located in the province of Central Sulawesi, aiming to identify the subsurface features, especially geological structures related to permeability zones by optimizing geophysical data. Magnetotelluric (MT) 3D inversion modelling is some of the latest methods to identify geological structural patterns in geothermal systems. The results of the MT model and analysis its parameters can find variations in the distribution of subsurface resistivity, orientation of the direction of the prospect area, and indications of geological structure zones. The type and geometry of the geological structure associated with the high permeability zone can be complemented by determining the contrast of gravity values ​​and analysis of the maximum First Horizontal Derivative (FHD) and zero of the Second Vertical Derivative (SVD). Based on the analysis of geophysical data, it is possible to identify the permeability zone associated with the main structure, namely the Palu-Koro fault, delineate the geothermal reservoir at a depth of 1500-2000 meters and determine the location of well drilling. To visualize the geothermal system comprehensively, a conceptual model is developed by integrating the geophysical model with geological and geochemical data that are correlated with each other, therefore it can assist in determining the location of production well development.

Identifikasi Sesar dengan Menggunakan Metode Gaya Berat (Studi Kasus: Sulawesi Tengah)

The study of the geological structure of Sulawesi Island, especially the Central Sulawesi region, is very interesting because it has high complexity as a result of the dynamic interactions of the world's three main plates. Indications of high seismic activity and deformation processes in the Central Sulawesi region can be found from the morphological appearance and activity of several existing faults such as the Palu-Koro fault, the Lawanopo fault, and the Matano fault. The data used in this study are secondary data measuring the distribution of gravitational field anomalies (FAA) and topographical data using the Topex application. At CBA values ranging from 31 mGal to 56 mGal. The height anomaly on the CBA contour map is shown in red to light purple which has a value range of 40.7 mGal to 62.7mGal. Low anomaly is shown in light green to blue which has a value range of 27.3 mGal to 3.2 mGal. The regional gravity anomaly values range from 5.1 mGal to 62.8 mGal with a distribution of gravity anomalies from south to north. While in this study it can only be explained that the residual anomaly value is influenced by rock type and density. The high anomaly found in the southern part is thought to be caused by rocks having high density and being in a sedimentary rock environment which has low density.

Social Construction of Religious Attitude towards Disaster among Victims of Natural Disasters in Palu and Lombok

Every religion has teachings related to the best ways to cope with problems, including those caused by natural disasters. Thus, natural disasters can reshape the construction of religious attitudes among the community. Therefore, this research aims to understand how natural disasters are perceived by religious leaders in the aftermath of earthquakes in Palu and Lombok and how these perceptions impact the community's views on ideal religious attitudes after a disaster.
 This research employs a phenomenological approach with thematic data analysis techniques applied to research data collected through interviews with various religious leaders and community members in Lombok Island and Palu City, two regions that experienced natural disaster events in 2018.
 The research findings suggest that, despite the resurgence of a back-to-nature sentiment following the disasters in Lombok, for the Wetu Telu Muslim community, this sentiment carries a deeper meaning than merely promoting an environmentally conscious way of life. It signifies a return to a way of life rooted in traditions passed down through generations, a way of life that has been eroded by the modernization brought about by the proselytizing efforts of the majority Muslim group over the past five decades. In Palu City, the earthquake and tsunami disaster in 2018 has also shaped the community's perception of disasters and influenced their religious behaviors in the post-disaster society. In general, three common perspectives were identified. First, a majority believes the disaster is a form of divine admonition from Allah due to various deviant behaviors in the society. Second, some believe the disaster is a result of the shifting of the Palu-Koro fault plates, an unavoidable natural event, grounded in empirical knowledge sources and disaster facts. Third, Muslim groups view the disaster as a test from Allah. These three perspectives have essentially shaped a unique religious attitude among the community expressed in various forms of religiosity.

The Study of Seismic Hazard in Near-Fault Areas Using Probabilistic and Deterministic Approach

Earthquake is one of the most common natural disasters in Indonesia and usually destroys both high and low-rise buildings as well as triggers liquefaction and Tsunami. This means it is important to provide a robust building design with the ability to resist earthquake load and other induced phenomena. One of the methods commonly used to determine the relevant response spectrum of the bedrock is seismic hazard analysis which can be either Probabilistic Seismic Hazard Analysis (PSHA) or Deterministic Seismic Hazard Analysis (DSHA). The application of PSHA allows the representation of the response spectrum of an earthquake using the return period, thereby providing the engineers with the flexibility of selecting the appropriate natural period. Meanwhile, DSHA is based on geological observations and empirical data that can be easily understood. This research discussed the greater influence of seismic hazard analysis on the bedrock response spectrum of near-fault areas including Bandung situated at a distance of 12.9 km from Lembang Fault, Palu at 3 km from Palu Fault, and Yogyakarta at 8.5 km from Opak Fault. Moreover, EZFRISK Program was used to generate a response spectrum at bedrock and the results showed that PSHA is consistently more conservative than DSHA. It was also noted that there are significant differences at shorter periods for Palu site but these differences were observed at the natural period between 1s and 2s for Bandung and Yogyakarta sites.

Liquefaction potential analysis for Palu City based on CPT method

During the 28 September 2018 Palu-Donggala earthquake, liquefaction was also a prominent hazard causing significant damage to buildings and infrastructures in Palu City. To mitigate such a hazard in Palu City, knowledge of the depth of the liquified soil layer is necessary. This paper presents the results of CPT-based liquefaction potential analysis in some locations around the city where sand boiling and ground settlement occurred. The analysis shows that liquefaction occurs at various depths less than 15 m and may induce ground settlement up a few centimeters. In the Palu-Koro Fault zone, the liquified sand layer is likely thicker than in other locations. Consequently, the total ground settlement is higher than in other locations The results of this study suggest that the liquefaction potential should be accounted for in the development of Palu City to reduce future earthquake risk.

Climate-controlled sensitivity of lake sediments to record earthquake-related mass wasting in tropical Lake Towuti during the past 40 kyr

Located at the triple junction of the Pacific, Eurasian and Sunda plates, the Island of Sulawesi in Indonesia is one of the most tectonically active places on Earth. This is highlighted by the recurrence of devastating earthquakes such as the 2018 Mw 7.5 earthquake that damaged the city of Palu and caused several thousand fatalities in central Sulawesi. The majority of large-magnitude earthquakes on Sulawesi are related to stress release along major strike-slip faults such as the Palu-Koro Fault and its southern extensions, the Matano and Lawanopo Faults. To date, information on the frequency and magnitude of past major events on these faults is limited to instrumental records and historical sources restricted to the last century, whereas information from natural archives is completely lacking. Lake-sediment records can fill this gap, but a detailed assessment of the various factors that influence the sensitivity of sediment successions to past earthquakes is required to evaluate their suitability. Lake Towuti, situated in Eastern Sulawesi, is known for its paleoclimate record and also promises to be a key site to generate a paleoseismology record for Sulawesi. The lake lies close to the highly active Matano and Lawanopo strike-slip faults and thereby is an ideal archive for past earthquakes that have occurred in the surrounding area. Here we combine high-resolution chirp seismic data with lithostratigraphic and petrophysical data of sediment piston cores to assess the recurrence of seismically generated mass-transport and turbidite deposits. Three major seismic-stratigraphic units are distinguished in the upper ∼10 m of the sediment succession and linked to differences in the frequency of mass-wasting during the past 60 kyrs. The evidence of a more turbidite-prone period between 12 and 40 ka is roughly coincident with a dry phase and associated lake-level lowstand during the last glacial period at Lake Towuti. Hence, we suggest that climate strongly influences the sensitivity of slopes to fail during seismic shaking in this tropical setting as a consequence of lowstand-forced sediment redeposition from the shelves onto the slopes and into the basins. As climate significantly impacts the sensitivity of the lacustrine sediments to record earthquake-related mass wasting deposits, we suggest that the frequency of mass-transport deposits can additionally be employed as a quantitative indicator for past changes in hydroclimate in these tropical settings.

Tectonic landform and paleoseismic events of the easternmost Matano fault in Sulawesi, Indonesia

The 190-km-long Matano fault is a major left-lateral strike-slip fault in Sulawesi, Indonesia that accommodates the rapid westward motion of the Pacific plate relative to the Australian plate. The Matano fault has remained unruptured at least in the past two centuries. The lack of geologic information, such as precise active fault traces, paleoseismic history, and slip rates has been a significant barrier to assessing the seismic hazards of the Matano fault. This paper presents the results of tectonic geomorphic and paleoseismic investigations on the 30 km long easternmost portion of the Matano fault. We identified four geometrical fault segments, documented five surface faulting events, and calculated a surface-rupturing earthquake recurrence interval of 200–470 years and a slip rate of 21 ± 9 mm/yr. The timing of the most recent surface-rupturing earthquake was constrained between 1432 and 1819 CE with an estimated Mw ∼ 7.4 and a probable rupture length of ∼110 km. At least 200 years have passed since the latest faulting event, exceeding the shortest recurrence interval. Thus, the next surface-rupturing earthquake is already due. Integrating our interpretations with results from several published studies clarifies that the Matano fault slips slower than the Palu-Koro fault and connects to the South Sula fault in addition to the Tolo thrust.

Diversity of substrate type, ethnomycology, mineral composition, proximate, and phytochemical compounds of the Schizopyllum commune Fr. in the area along Palu-Koro Fault, Central Sulawesi, Indonesia

Schizophyllum commune Fr. is a wild macro fungus species, which is often used as a food source by the indigenous Kaili tribe along the Palu-Koro fault, Central Sulawesi, Indonesia. This fungus has a wide variety in terms of the weathered wood substrate as a place to grow and is found in almost all types of ecosystems. Although its diversity has been investigated, there is no identification of the weathered wood type as a substrate for growth. Some communities in Indonesia have not also known its potential and benefits. Therefore, this research aims to determine the wood type that grows S. commune fungus, ethnomycology, mineral composition, proximate, and phytochemical compounds. It was carried out using the descriptive explanatory approach and the fungi location as well as wood substrate sampling, was determined through the purposive sampling technique in forest areas, agroforestry, and community gardens along the Palu-Koro fault, Central Sulawesi. The samples of unknown wood types were through the collection of tree parts, namely twigs, leaves, flowers, and fruits, which were brought to Herbarium Celebense, Tadulako University for identification. Analysis of mineral content, proximate, and fungal phytochemical compounds was carried out based on the method according to the existing protocol. The results showed that 92 types of rotted wood found where the fungus S. commune grew, belonged to 36 families. The nutritional content is also good, although it varies based on the type of wood growing media. Therefore, it can be used and processed into various health-beneficial food products. This showed that domestication of the fungus needs to be carried out to support its commercialization as food and medicine in the future.

Seismic microzonation based on HVSR inversion results for shear wave (Vs30) mapping and soil vulnerability in West Sulawesi and South Sulawesi Regions

The Horizontal to Vertical Spectral Ratio (HVSR) is a seismic analysis method used to obtain information about subsurface geological characteristics. This method is based on the spectral ratio analysis between the horizontal and vertical components of earthquakes or other vibration sources. HVSR has proven to be an effective tool in evaluating rock layers, layer thickness, rock hardness, and geological hazard potential. In the HVSR method, seismic data are measured using three-component seismometers, the N-S (North-South), E-W (East-West), and vertical components. In this study, the HVSR method is used for Vs30 inversion to estimate shear wave velocity at a depth of 30m. The southern and western regions of Sulawesi have various geological conditions and high seismicity levels. The results of this inversion can be used for mapping soil vulnerability indices. The obtained soil vulnerability index values indicate high vulnerability near the Palu-Koro fault, with A0 9.27 at F0 3.2 Hz. This method can also estimate shear wave velocity values at a depth of 30 m. Vs30 values range from 200 m/s to 500 m/s at various measurement points, indicating variability. According to the SNI 1726:2012 and NEHRP classifications, the research area has soil conditions ranging from medium to soft.

The Identification of Earthquake Shake Levels in Palu City Based on Mw 6,8 Shakemap Scenario by Palu Koro Fault

Palu city is an active earthquake region, mainly sourced from the activity of the Palu Koro Fault. Referring to the Mw7.4 Central of Sulawesi earthquake on September 28th, 2018 with ground shaking intensity reached VII-IX MMI level in Palu. As a supporting data and preparation of an earthquake contingency plan document in Palu City, we proposed 3 sources of earthquake scenarios in the Palu Koro fault at a depth of 11 km, namely Mw6.8 in the Palu City Segment with coordinates 119.830 E – 0.800 S, Mw 6.9 in the Saluki segment with coordinates 120.010 E - 1,250 S and Mw 7.1 in the Makassar Strait segment with coordinates 119.750 E – 0.380 S. The worst-case scenario is that the Mw6.8 earthquake in Palu City can reach VI-VIII MMI.

KABAR BENCANA DARI SURAT KABAR: MEMBACA ULANG SEJARAH BENCANA 20 MEI 1938

The earthquake and tsunami that occurred in Tomini Bay and Palu Bay, on May 20, 1938, was one of the natural disasters that attracted much attention in the archipelago at that time. This research was conducted to thoroughly review the history of the 20 May 1938 disaster, in the eyes of the newspapers published in the Dutch East Indies and the Netherlands at that time. Newspaper sources from the disaster were considered capable of presenting an overview of the atmosphere after the disaster and how the handling efforts were carried out by the Dutch East Indies government and religious and humanitarian organizations. This study used historical methods consisting of heuristics (finding sources), source criticism, interpretation (meaning), and historiography (writing history). It is hoped that the results of this study can be a learning material for people living in the Central Sulawesi region, especially Palu Bay which is crossed by the Palu Koro Fault, and Tomini Bay which is crossed by several faults, one of which is the Tokararu Fault.

Characteristics of Palu-Koro Fault based on Derivative Analysis and Euler Deconvolution Model of Gravity Data

Indonesia is located at the confluence of three plates, namely the Eurasian, Indo-Australian, and Pacific plates which causes the formation of an active fault line. One of these active faults is the Palu-Koro fault, Sulawesi, with a shift rate of 30-44 mm/year. A geophysical method such as gravity determines the fault’s characteristics. Gravity data is processed by a derivative analysis process in the form of First Horizontal Derivative (FHD) and Second Vertical Derivative (SVD), which is carried out to represent the type of fault, and the Euler Deconvolution method is used to determine the location and depth of the fault anomaly source. The results show that the Palu-Koro fault has a high anomaly value in the west of 0.00557-0.01087 mGal in the north-south direction on the FHD map and an anomaly value of 0 in the north-south direction on the SVD map. The source of the anomaly can be seen more clearly in the results of the Euler Deconvolution modelling at a depth of 50-400 m from the topography of the study area. The Palu-Koro fault is proven to have many structures at shallow depths with very active movements that can trigger earthquakes.

Back-projection results for the M w 7.5, 28 September 2018 Palu earthquake-tsunami

A back-projection technique allows seismologists to analyse rupture properties once seismic signals from a dense array of seismic networks are available. The observed waveforms are then traced back in space and time to the source region of an earthquake under investigation. In this study, the method utilised the back-projection image of the recorded high-frequency P-seismic waveforms filtered at 0.25-1.0 Hz by Multiple Signal Classification (MUSIC) processing to estimate the extent and the spread of earthquake rupture propagation of the M w 7.5 Palu event on 28 September 2018, generating a severe tsunami. This study aims to estimate rupture duration, its extent (the distance over which rupture propagates) and the corresponding speed, and rupture directivity (where most of the seismic energy propagates). The results revealed that the front of rupture propagates slightly offset southward at about 2.9 km/s over a distance of ~140 km away from the epicentre for about 49 s before slowing down at much smaller amplitudes after reaching the south end of Palu Bay. This finding is consistent with an NNW-SSE orientation of the active Palu-Koro Fault lying along the bay, suggesting that the strong ground motion is associated with the fault activities. This study has therefore substantial implications for enhanced earthquake and tsunami early warnings, helping the government and local authority build community resilience by warning people at risk from future possible earthquake and tsunami hazards.

Slope stability analysis during an earthquake in flow-slide affected area of Jono Oge

On September 28th, 2018, the earthquake with a moment magnitude (Mw) 7.5 due to strike-slip Palu-Koro Fault in Central Sulawesi caused a major geological failure. In the Jono Oge area, the earthquake-induced liquefaction and flow-slide occurred on relatively flat ground with an average slope of 2%. In this paper, the safety factor for slope stability analysis was determined by shear strength reduction caused by the earthquake at the potentially liquefied soil layer, varying peak ground acceleration values, and groundwater level conditions. This analysis evaluated the potential of ground movement occurrence in Jono Oge with the condition of soil layer pre and post the Palu-Donggala earthquake that happened in 2018 using GeoStudio Slope/W geotechnical software. The analysis was conducted on the cross-section of the soil layer based on three boreholes incorporating standard penetration test (SPT) data on the study area. The analysis results showed ground movement potential because of the seismic loads and groundwater level conditions. The lower the safety factor of slope stability, the higher the ground movement potential in flow-slide affected area. This ground movement potential could trigger the occurrence of flow-slide in Jono Oge area.

Analysis of Coastline Changes in Palu Bay, Central Sulawesi after the 2018 Tsunami Based on Sentinel 1 Satellite Imagery Using the Digital Shoreline Analysis System (DSAS) Method

The Palu-Donggala earthquake that occurred on September 28, 2018 caused additional disasters in the form of liquefaction and tsunami. The tsunami that hit the coastal area of Palu Bay caused considerable damage, indicating a change in the coastline. The purpose of this study was to determine the changes in the coastline that occurred in Palu Bay, Palu City, Central Sulawesi as a result of the Tsunami. The data used in this study are Sentinel 1 satellite imagery before and after the Tsunami occurred. The coastline at each time is obtained from the extraction of Sentinel 1 satellite imagery. Analysis of shoreline change uses quantitative descriptive techniques with the help of the DSAS tool with change analysis based on the Net Shoreline Movement (NSM) method which is integrated with ArcGIS software. The results show that there has been a significant change in the coastline in Palu Bay, Palu City, Central Sulawesi. Coastline changes that occur are in the form of abrasion and accretion conditions, but are more dominated by abrasion. The highest abrasion of -167.53m is found on transect 309 which is located in the District of Mantikulore, and the lowest abrasion value of -0.43m is found on transect 242 which is located in the Ulujadi District. Meanwhile, the highest accretion value of 47.27m is found on transect 105 which is located in the West Palu District, and the lowest abrasion value of 0.56m is found on transect 68 which is also located in the West Palu District. The magnitude of the change in coastline that occurred in Palu Bay, Palu City, Central Sulawesi after the Tsunami was influenced by the openness of the coastal area to wave blows, the oval and narrow morphology of Palu Bay and the occurrence of ground deformation in the Palu-Koro Fault

Variasi spasial dan temporal nilai-b pada gempa bumi di wilayah Sulawesi Tengah, Gorontalo, dan sekitarnya menggunakan metode robust fitting

This study discusses variation in seismic and tectonic modeled by a Gutenberg-Richter relationship for earthquakes in the Central Sulawesi, Gorontalo, and surrounding areas using the Robust Fitting Method (RFM) with the weight function of Tukey’s bisquare. The declustering process on earthquake data is carried out using the Reasenberg equation. The values for both parameters are analyzed spatially and temporally. In the spatial analysis, the research area is divided into 43 grids. In the temporal analysis, the research area is divided into zone A and zone B. The data grouping is done using a sliding time window method, i.e., grouping 50 earthquake catalogs with 5 overlapping events. The results according to spatial analysis show that the b-values range from 0.38 – 1.19. Areas with low b-values (0.38 – 0.7) occur around the Palu-Koro Fault, i.e., Palu city, Malacca strait, and to Toli-Toli, and also in the northern region of Gorontalo, i.e., the subduction plate of the Sulawesi Sea. Meanwhile, high b-values (0.71 – 1.19) are in the Tomini Bay area which is an area with frequent occurrence of earthquakes but has the small potential to generate large-scale earthquakes. The results of the temporal b-value estimation in zones A and B range between values of 0.38 - 1.25. The b-values appear to decrease before the occurrence of major earthquakes in 1996 and 2018 in zone A. The b-values decreased before the occurrence of major earthquakes in 1990, 1991, 2000, and 2008 in zone B. However, the b-values cannot be used as a precursor before the big earthquake in 1997.
 Keywords: Tukey’s bisquare, Reasenberg equation, Gutenberg-Richter relationship, sliding time window, Robust Fitting Method. MSC2020: 86A15

Karakteristik Dan Petrogenesa Batuan Beku Granit Di Daerah Sibayu, Kecamatan Balaesang, Kabupaten Donggala, Provinsi Sulawesi Tengah

The tectonic history of Sulawesi is closely related to the activities of the three major world plates that surround it. This results in the complexity of geological conditions on the island of Sulawesi, including the diversity of rock types. One of the most common types of rock is igneous granite, which is widespread in the Sibayu area, Donggala Regency, Central Sulawesi Province. This study aims to determine the characteristics and petrogenesis of igneous granite using megascopic and microscopic or petrographic observation methods. The results showed that the rock has a megascopic appearance in the form of a grayish-white fresh color and a brownish weathered color, a holocrystalline texture, a massive structure, and a mineral composition consisting of orthoclase, amphibole, and quartz. Its microscopic appearance shows a brownish-transparent color on parallel nikol, on brown cross-linked nikol, light gray to dark gray, mineral size 0.15-0.05 mm, the average mineral composition is orthoclase (41.25% ), quartz (43.75%), biotite (11.25%) and plagioclase (3.75%). Based on these data, it can be concluded that the rocks are Late Miocene to Late Pliocene, which proves that the Palu-Koro fault was still active during the Late Miocene to Late Pliocene. The presence of biotite in granitic rocks characterizes S-Type granite which is formed deep below the earth's surface which is characterized by euhedral-subhedral forms.

The role of fault interaction in earthquake migration in Central Sulawesi, Indonesia

Over the past 50 years, a sequence of destructive earthquakes, such as the 1968 (Mw 7.2), 1996 Tonimi (Mw 7.9), and 2018 Palu (Mw 7.5) earthquakes, occurred on the Palu-Koro strike-slip fault and the Minahassa Megathrust, which caused catastrophic disasters in Central Sulawesi, Indonesia. To explore the relationship between fault interaction and earthquake migration in this target area, we simulated the Coulomb stress change (ΔCFS) caused by 13 historical large earthquakes (M ≥ 6.0) since 1968. We show that the 1968 earthquake (Mw 7.2) on the Palu-Koro Fault promoted the 1996 earthquake sequence (Mw 7.9, Mw 6.6, and Mw 7.0) on the Minahassa Megathrust by transferring positive stress to its western edge with a maximum ΔCFS value of 124 kPa before 1996. Consequently, the 1996 earthquake (Mw 7.9) promoted six large earthquakes (M ≥ 6.0) including the 2018 Palu earthquake (Mw 7.5) on the Palu-Koro Fault between 1998 and 2020 via stress loading over the entire Palu-Koro Fault with a maximum ΔCFS value of 76 kPa. Via a positive feedback, these six earthquakes have increased stress at the western edge of the Minahassa Megathrust with a maximum ΔCFS value of 265 kPa up to 2020, resulting in increased seismic and consequent tsunami hazards in this region. Based on these risks, close attention should be paid to the future seismic hazards in Central Sulawesi. These findings suggest that the Palu-Koro Fault and the Minahassa Megathrust constitute a coupled fault system in which seismicity in either fault might bring the other closer to failure. Our results provide new insights into the causes of earthquake generation, migration, and hazard estimation in Central Sulawesi, and provide a basis for understanding stress transfer and seismic activity in strike-slip and thrust fault systems globally.

Morpho-bathymetric features of the Southwest Celebes Sea

The Southwest Celebes Sea lies within the region of Celebes Sea (also known locally as Sulawesi Sea)-Makassar Strait gateway which is controlled by active tectonic of North Sulawesi Trench and Palu-Koro Fault zone. In addition, this region is the major inter-ocean route of Indonesian Throughflow (ITF). Using the high-resolution multibeam bathymetry data supplemented with 2D seismic profiles, this study describes major morpho-bathymetric features that can be observed within the Southwest Celebes Sea. There are 4 types of morpho-bathymetric features: structural features, erosional features, gravitational features, and depositional features. The dominant structural related tectonic features and gravitational features mainly occur in the North Sulawesi Fold-Thrust Belt associated with the formation of the North Sulawesi Trench and Palu-Koro Fault zone. Whereas, to the northern part, the deeper area of the Celebes Sea and the region on the west are mainly controlled by erosional and depositional features. The identification of morpho-bathymetric features provides useful information for basin analysis study and present-day or future offshore activities such as infrastructure engineering related to geohazard potential caused.