The interpretation of subsurface in the Semarang City with 3D inversion model using the Chi Fact ... more The interpretation of subsurface in the Semarang City with 3D inversion model using the Chi Fact algorithm has been carried out to reveal the subsurface especially related to the presence of groundwater basins. The gravity data model in this research uses 80 stations with a research area of 20 km2 which is specialized in the surrounding area of Kaligarang district. The results of the 3D inversion using the Chi Fact algorithm founded the distribution of subsurface rock density values in the Semarang City area ranging from 1.6 gr/cc to 2.98 gr/cc. The distribution of subsurface density values indicates the subsurface geological structure of the Semarang City area had a normal fault leading to the southeast.
Landslide is one of the disasters that often occurs in Pati Regency. This study aims to analyze t... more Landslide is one of the disasters that often occurs in Pati Regency. This study aims to analyze the risk of landslides in Pati Regency. The landslide risk index in Pati Regency is carried out by analyzing three components: the hazard index, vulnerability, and capacity according to BNPB head regulation No. 2 the year 2012 concerning General Guidelines for Disaster Risk Assessment. The results showed a high landslide risk index in 49 villages out of 406 throughout Pati Regency. The sub-districts with the highest landslide risk index are Sukolilo District with nine villages and Gunungwungkal with seven villages. The high-risk index in the area is influenced by the high danger of landslides and the lack of existing capacity. The recommended recommendations include installing EWS, socializing knowledge on disaster preparedness, improving emergency response management, increasing community participation, evaluating RTRW, and reviewing vegetation types.
IOP Conference Series: Earth and Environmental Science, 2022
Surakarta City is the center of economic activity in the great Solo area. As a result, land use c... more Surakarta City is the center of economic activity in the great Solo area. As a result, land use changes occur very quickly. This study aims to identify land use and land changes due to their effects on groundwater levels in Surakarta City. The method used in this research is a descriptive-quantitative method. The analysis technique used is time series, by comparing image data for 2003, 2008, and 2019. The image is obtained from Google Earth and then visually interpreted in a GIS application to get the land use area. Land use in Surakarta City includes buildings, agriculture, vacant land, tourist land, waters, settlements, green open spaces, rice fields, shrubs, and dryland agriculture. The results of image processing show that there is a change in land use in Surakarta City. The results show that there is a relationship between land use/change with an increase in population and ground water use. The areas most affected by the decline in groundwater are in the central part of the cit...
IOP Conference Series: Earth and Environmental Science, 2022
Groundwater use in Sukoharjo increases every year. This study aims to identify the depth of groun... more Groundwater use in Sukoharjo increases every year. This study aims to identify the depth of groundwater in the northern part of Sukoharjo district as a solution to fulfill agricultural irrigation using the Vertical Electrical Sounding (VES) method. This study used the OYO resistivity meter. Research data processing uses uses Non-Linear Optimization method to obtain the true layer resistivity value vertically. The research was conducted in 5 different locations using the Vertical Electrical Sounding (VES) method with Schlumberger configuration. The length of the research site is 250 - 300 meter with a target depth of more than 120 meters. Based on the value of rock resistivity can be determined the depth of groundwater level in the northern Sukoharjo district. The results of the interpretation showed the groundwater level is at a depth of 15.2 - 82.21 meter consisting of a layer of top soil, sand, gravel and clay rocks.
Telah dilakukan penelitian tentang analisis karakteristik sumur bor. Penelitian ini merupakan sua... more Telah dilakukan penelitian tentang analisis karakteristik sumur bor. Penelitian ini merupakan suatu contoh penelitian tentang analisis karakteristik sumur bor di daerah batu karang dan tandus. Penelitian mengambil contoh di sumur RSPTN Universitas Udayana berlokasi di Jimbaran Badung Bali. Analisis yang dilakukan efisiensi sumur (Ew), faktor pengembangan sumur (Fd), perbaikan sumur (C) dan debit optimum (Q opt ). Hasil penelitian didapatkan bahwa berdasarkan hasil pengukuran geolistrik, pada sumur bor memang ada akuifer. Sumur yang dibikin termasuk sumur yang efesien dengan tingkat efisiensi 84,71%. Ini berarti sangat efesien untuk pengambilan air. Sumur memiliki faktor pengembang 0,077864 hari/m 3 Ini berarti sumur sangat baik untuk dikembangkan. Nilai C = 28994,2. Ini berarti apabila sumurnya ada kendala misalnya debitnya mengecil, maka sumur sulit dikembalikan menjadi seperti semula. Kapasitas jenis (Sc) rata-rata didapat: 0,0196908 m 2 /s, nilai ini lebih besar dari 0,005. In...
2020 IEEE Asia-Pacific Conference on Geoscience, Electronics and Remote Sensing Technology (AGERS), 2020
The tidal of the sea is a phenomenon of rising and falling sea levels periodically caused by the ... more The tidal of the sea is a phenomenon of rising and falling sea levels periodically caused by the influence of gravity from celestial objects, especially the moon and sun. The purpose of this research is to determine the tidal type in West Sumatra Water, especially in Sabang, Sibolga, and Padang cities. Tidal type can be used as a reference for the port to determine when the ship can go in or out of the port. We used satellite altimetry and tide gauge data. Tidal types in the West Sumatra Waters are influenced by the characteristics of tides in the Andaman Sea and the Indian Ocean. Determining the tidal type required the Formzahl number obtained from the comparison of tidal constants using harmonic analysis. We obtained that the West Sumatra Waters has semidiurnal tidal types with a Formzahl number 0.2013 at Sabang station and has a mixed tidal type (semidiurnal dominant) at Padang and Sibolga stations with Formzahl number values of 0.4306 and 0.4893, respectively. We found 9 tidal c...
Kata kunci : pelatihan geofisika, UNS, resistivitas, seismik refraksi Telah dilakukan P2M program... more Kata kunci : pelatihan geofisika, UNS, resistivitas, seismik refraksi Telah dilakukan P2M program IbIKK untuk Memperluas akses bagi masyarakat dan resource sharing di bidang ilmu geofisika dan aplikasinya. Program ini berupa pelatihan atau workshop tentang metode geofisika. Dengan tujuan agar keberadaan minat geofisika dapat dikenal oleh swasta dan instansi pemerintah. Pelatihan diadakan 2 kali pada bulan September dan Oktober 2012 dengan tema pelatihan berbeda. Pertama Metode Resistivitas untuk aplikasi airtanah dan Geoteknik. Kedua metode resistivitas dan metode seismik refraksi. Hasilnya pada pelatihan pertama tanggal 7-8 September 2012 diikuti 39 peserta dengan rincian 32 dari UNS, dan 7 peserta dari luar UNS (2 (ITB), 2(UPN), 1 (UNIVET), 2(LSM)). Sedangkan pelatihan kedua tanggal 10-11 Oktober 2012 diikuti 12 peserta dengan rincian 4 dari UNS dan 8 dari luar UNS (2 (Aneka Tambang), 2 (UNSOED), 1 (UNJ), 1 (UIN),1 (UPI) dan 1(UPN)). Dari kedua pelataihan menunjukkan untuk pelatih...
In the last two decades, the city of Surakarta has shown significant population development, as w... more In the last two decades, the city of Surakarta has shown significant population development, as well as in industry and tourism. This development must be accompanied by the provision of water resources for the lives of the population. As we know that in 2015 and 2019, there was a long dry season that resulted in a lack of water for residents and for the hotel industry, where most residents of Surakarta and the hotel industry are located in the southern part of the city of Surakarta. Therefore, the purpose of this study was to determine the level of groundwater aquifers in the south part of the city of Surakarta. We used the vertical electrical sounding (VES) method with the Schlumberger configuration at 10 survey locations. The current electrode interval in the Schlumberger configuration is from 1.5 meters up to 300 meters. With this stretch of electrode current, it is expected to reach target depth of up to 150 meters. Data processing uses the principle of non-linear optimization m...
In 2019, most of the areas in Central Java Indonesia experienced drought disaster. There are 3 di... more In 2019, most of the areas in Central Java Indonesia experienced drought disaster. There are 3 districts that conduct emergency response due to drought disasters. If there is another drought in this year during Covid-19 pandemic, it will be very fatal due to the need for more water than usual. Besides being used for daily needs, water is also needed for washing hands and bathing during the Covid-19 pandemic. This study aims to determine the level of drought in Central Java province and provide solutions on how to reduce the drought strategy so as not to aggravate the spread of Covid-19. The method used to determine rainfall prediction is the Canonical Correlation Analysis (CCA) method with input data of average monthly rainfall for approximately 30 years in Central Java. Then to determine the drought map using the Standardized Precipitation Index (SPI) method with input data of rainfall prediction for the last 3 months from the CCA method. The results of data processing show that in...
The Pulutan Village is in the karst area consisting mostly of limestone so that during the dry se... more The Pulutan Village is in the karst area consisting mostly of limestone so that during the dry season will cause drought. Drought caused by water is located below the surface so it is difficult to take and known location, it is necessary to investigate the presence of aquifer. The study aims to find out the structures beneath the surface, the depth of the aquifer, and to get cross-section results in 3-dimensional form. The method used in this research is the method of geoelectric resistivity with Schlumberger configuration using the 3 points sounding. The results of the study were obtained that aquifer is located on a coating of tuff sandstone with a resistivity between 2.40 ňm to 4.15 ňm. The second Sounding point, it is known that there is a large prospect of groundwater visible from the thickness of the aquifer layer.
The interpretation of subsurface in the Semarang City with 3D inversion model using the Chi Fact ... more The interpretation of subsurface in the Semarang City with 3D inversion model using the Chi Fact algorithm has been carried out to reveal the subsurface especially related to the presence of groundwater basins. The gravity data model in this research uses 80 stations with a research area of 20 km2 which is specialized in the surrounding area of Kaligarang district. The results of the 3D inversion using the Chi Fact algorithm founded the distribution of subsurface rock density values in the Semarang City area ranging from 1.6 gr/cc to 2.98 gr/cc. The distribution of subsurface density values indicates the subsurface geological structure of the Semarang City area had a normal fault leading to the southeast.
Landslide is one of the disasters that often occurs in Pati Regency. This study aims to analyze t... more Landslide is one of the disasters that often occurs in Pati Regency. This study aims to analyze the risk of landslides in Pati Regency. The landslide risk index in Pati Regency is carried out by analyzing three components: the hazard index, vulnerability, and capacity according to BNPB head regulation No. 2 the year 2012 concerning General Guidelines for Disaster Risk Assessment. The results showed a high landslide risk index in 49 villages out of 406 throughout Pati Regency. The sub-districts with the highest landslide risk index are Sukolilo District with nine villages and Gunungwungkal with seven villages. The high-risk index in the area is influenced by the high danger of landslides and the lack of existing capacity. The recommended recommendations include installing EWS, socializing knowledge on disaster preparedness, improving emergency response management, increasing community participation, evaluating RTRW, and reviewing vegetation types.
IOP Conference Series: Earth and Environmental Science, 2022
Surakarta City is the center of economic activity in the great Solo area. As a result, land use c... more Surakarta City is the center of economic activity in the great Solo area. As a result, land use changes occur very quickly. This study aims to identify land use and land changes due to their effects on groundwater levels in Surakarta City. The method used in this research is a descriptive-quantitative method. The analysis technique used is time series, by comparing image data for 2003, 2008, and 2019. The image is obtained from Google Earth and then visually interpreted in a GIS application to get the land use area. Land use in Surakarta City includes buildings, agriculture, vacant land, tourist land, waters, settlements, green open spaces, rice fields, shrubs, and dryland agriculture. The results of image processing show that there is a change in land use in Surakarta City. The results show that there is a relationship between land use/change with an increase in population and ground water use. The areas most affected by the decline in groundwater are in the central part of the cit...
IOP Conference Series: Earth and Environmental Science, 2022
Groundwater use in Sukoharjo increases every year. This study aims to identify the depth of groun... more Groundwater use in Sukoharjo increases every year. This study aims to identify the depth of groundwater in the northern part of Sukoharjo district as a solution to fulfill agricultural irrigation using the Vertical Electrical Sounding (VES) method. This study used the OYO resistivity meter. Research data processing uses uses Non-Linear Optimization method to obtain the true layer resistivity value vertically. The research was conducted in 5 different locations using the Vertical Electrical Sounding (VES) method with Schlumberger configuration. The length of the research site is 250 - 300 meter with a target depth of more than 120 meters. Based on the value of rock resistivity can be determined the depth of groundwater level in the northern Sukoharjo district. The results of the interpretation showed the groundwater level is at a depth of 15.2 - 82.21 meter consisting of a layer of top soil, sand, gravel and clay rocks.
Telah dilakukan penelitian tentang analisis karakteristik sumur bor. Penelitian ini merupakan sua... more Telah dilakukan penelitian tentang analisis karakteristik sumur bor. Penelitian ini merupakan suatu contoh penelitian tentang analisis karakteristik sumur bor di daerah batu karang dan tandus. Penelitian mengambil contoh di sumur RSPTN Universitas Udayana berlokasi di Jimbaran Badung Bali. Analisis yang dilakukan efisiensi sumur (Ew), faktor pengembangan sumur (Fd), perbaikan sumur (C) dan debit optimum (Q opt ). Hasil penelitian didapatkan bahwa berdasarkan hasil pengukuran geolistrik, pada sumur bor memang ada akuifer. Sumur yang dibikin termasuk sumur yang efesien dengan tingkat efisiensi 84,71%. Ini berarti sangat efesien untuk pengambilan air. Sumur memiliki faktor pengembang 0,077864 hari/m 3 Ini berarti sumur sangat baik untuk dikembangkan. Nilai C = 28994,2. Ini berarti apabila sumurnya ada kendala misalnya debitnya mengecil, maka sumur sulit dikembalikan menjadi seperti semula. Kapasitas jenis (Sc) rata-rata didapat: 0,0196908 m 2 /s, nilai ini lebih besar dari 0,005. In...
2020 IEEE Asia-Pacific Conference on Geoscience, Electronics and Remote Sensing Technology (AGERS), 2020
The tidal of the sea is a phenomenon of rising and falling sea levels periodically caused by the ... more The tidal of the sea is a phenomenon of rising and falling sea levels periodically caused by the influence of gravity from celestial objects, especially the moon and sun. The purpose of this research is to determine the tidal type in West Sumatra Water, especially in Sabang, Sibolga, and Padang cities. Tidal type can be used as a reference for the port to determine when the ship can go in or out of the port. We used satellite altimetry and tide gauge data. Tidal types in the West Sumatra Waters are influenced by the characteristics of tides in the Andaman Sea and the Indian Ocean. Determining the tidal type required the Formzahl number obtained from the comparison of tidal constants using harmonic analysis. We obtained that the West Sumatra Waters has semidiurnal tidal types with a Formzahl number 0.2013 at Sabang station and has a mixed tidal type (semidiurnal dominant) at Padang and Sibolga stations with Formzahl number values of 0.4306 and 0.4893, respectively. We found 9 tidal c...
Kata kunci : pelatihan geofisika, UNS, resistivitas, seismik refraksi Telah dilakukan P2M program... more Kata kunci : pelatihan geofisika, UNS, resistivitas, seismik refraksi Telah dilakukan P2M program IbIKK untuk Memperluas akses bagi masyarakat dan resource sharing di bidang ilmu geofisika dan aplikasinya. Program ini berupa pelatihan atau workshop tentang metode geofisika. Dengan tujuan agar keberadaan minat geofisika dapat dikenal oleh swasta dan instansi pemerintah. Pelatihan diadakan 2 kali pada bulan September dan Oktober 2012 dengan tema pelatihan berbeda. Pertama Metode Resistivitas untuk aplikasi airtanah dan Geoteknik. Kedua metode resistivitas dan metode seismik refraksi. Hasilnya pada pelatihan pertama tanggal 7-8 September 2012 diikuti 39 peserta dengan rincian 32 dari UNS, dan 7 peserta dari luar UNS (2 (ITB), 2(UPN), 1 (UNIVET), 2(LSM)). Sedangkan pelatihan kedua tanggal 10-11 Oktober 2012 diikuti 12 peserta dengan rincian 4 dari UNS dan 8 dari luar UNS (2 (Aneka Tambang), 2 (UNSOED), 1 (UNJ), 1 (UIN),1 (UPI) dan 1(UPN)). Dari kedua pelataihan menunjukkan untuk pelatih...
In the last two decades, the city of Surakarta has shown significant population development, as w... more In the last two decades, the city of Surakarta has shown significant population development, as well as in industry and tourism. This development must be accompanied by the provision of water resources for the lives of the population. As we know that in 2015 and 2019, there was a long dry season that resulted in a lack of water for residents and for the hotel industry, where most residents of Surakarta and the hotel industry are located in the southern part of the city of Surakarta. Therefore, the purpose of this study was to determine the level of groundwater aquifers in the south part of the city of Surakarta. We used the vertical electrical sounding (VES) method with the Schlumberger configuration at 10 survey locations. The current electrode interval in the Schlumberger configuration is from 1.5 meters up to 300 meters. With this stretch of electrode current, it is expected to reach target depth of up to 150 meters. Data processing uses the principle of non-linear optimization m...
In 2019, most of the areas in Central Java Indonesia experienced drought disaster. There are 3 di... more In 2019, most of the areas in Central Java Indonesia experienced drought disaster. There are 3 districts that conduct emergency response due to drought disasters. If there is another drought in this year during Covid-19 pandemic, it will be very fatal due to the need for more water than usual. Besides being used for daily needs, water is also needed for washing hands and bathing during the Covid-19 pandemic. This study aims to determine the level of drought in Central Java province and provide solutions on how to reduce the drought strategy so as not to aggravate the spread of Covid-19. The method used to determine rainfall prediction is the Canonical Correlation Analysis (CCA) method with input data of average monthly rainfall for approximately 30 years in Central Java. Then to determine the drought map using the Standardized Precipitation Index (SPI) method with input data of rainfall prediction for the last 3 months from the CCA method. The results of data processing show that in...
The Pulutan Village is in the karst area consisting mostly of limestone so that during the dry se... more The Pulutan Village is in the karst area consisting mostly of limestone so that during the dry season will cause drought. Drought caused by water is located below the surface so it is difficult to take and known location, it is necessary to investigate the presence of aquifer. The study aims to find out the structures beneath the surface, the depth of the aquifer, and to get cross-section results in 3-dimensional form. The method used in this research is the method of geoelectric resistivity with Schlumberger configuration using the 3 points sounding. The results of the study were obtained that aquifer is located on a coating of tuff sandstone with a resistivity between 2.40 ňm to 4.15 ňm. The second Sounding point, it is known that there is a large prospect of groundwater visible from the thickness of the aquifer layer.
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