Seismic Hazard and Microzonation Study of Tanjung Region, North Lombok (Indonesia) using Microtremor Measurement

Tanjung Region is one of the severely damaged areas by the Lombok earthquake on June 22, 2013. Therefore, to anticipate the similar events, it is necessary to perform microzonation in this region. Objective of this study is to map the distribution of the physical quantities related to the vulnerability of area included the frequency characteristics, amplification factor, and soil vulnerability index. The results showed that the value of the resonant frequency in this region ranged from 0.401 to 16.92 Hz. In general, the lower frequency was 0.40 to 5.91 Hz contained 87 data (71%) were located in the north of the region, which meant that that area has a high vulnerability. While based on the H/V amplitude and vulnerability index, the zone that suffered severe damage on the earthquake of June 22, 2013, showed a different uncertainty of amplification and vulnerability index value.Wilayah Tanjung adalah salah satu daerah yang mengalami rusak parah akibat gempa Lombok pada tanggal 22 Juni 2013. Oleh karena itu, untuk mengantisipasi kejadian serupa, maka perlu untuk melakukan mikrozonasi di daerah tersebut. Tujuan dari penelitian ini adalah untuk memetakan distribusi besaran fisis yang terkait dengan kerentanan suatu daerah terhadap gempa bumi yang meliputi frekuensi respon, amplitudo getaran tanah dan indeks kerentanan tanah. Hasil penelitian menunjukkan bahwa nilai frekuensi resonansi di wilayah ini berkisar antara 0,401-16,92 Hz. Secara umum, frekuensi respon di daerah ini rendah yaitu 0,40-5,91 Hz dengan jumlah 87 data (71%) yang terletak di utara dari wilayah tersebut, yang berarti bahwa bagian utara wilayah memiliki kerentanan yang tinggi. Meskipun berdasarkan nilai amplitudo H/V dan indeks kerentanan, daerah yang mengalami kerusakan parah saat gempa 22 Juni 2013 menunjukkan pola amplifikasi dan indeks kerentanan yang sangat tidak biasa.

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Mikrozonasi di Daerah Plampang, Nusa Tenggara Barat

EKSPLORIUM ◽

10.17146/eksplorium.2021.42.1.6243 ◽

2021 ◽

Vol 42 (1) ◽

pp. 39

Author(s):

Eko Rudi Iswanto ◽

Theo Alvin Riyanto ◽

Hadi Suntoko

Keyword(s):

Seismic Vulnerability ◽

Volcanic Rocks ◽

Spectral Ratio ◽

Vulnerability Index ◽

Tectonic Activity ◽

Analysis Method ◽

The North ◽

Vulnerability Maps ◽

Vulnerability Map ◽

Microtremor Measurement

ABSTRAK Provinsi Nusa Tenggara Barat (NTB) merupakan daerah dengan aktivitas kegempaan yang tinggi. Fenomena ini disebabkan oleh adanya aktivitas tektonik sebagai akibat pertemuan Lempeng Eurasia-Australia (zona subduksi) di bagian selatan dan Sesar Flores di bagian utara serta adanya keberadaan sesar-sesar lokal. Terkait dengan rencana pengembangan kawasan Samota di Pulau Sumbawa, NTB, perlu dilakukan suatu kajian kegempaan. Tujuan penelitian ini adalah memetakan indeks kerentanan seismik (Kg) melalui pengukuran mikrotremor dengan analisis menggunakan metode Horizontal to Vertical Spectral Ratio (HVSR). Hasil penelitian berupa peta kerentanan seismik daerah Plampang yang menunjukkan bahwa sisi utara lokasi penelitian memiliki indeks kerentanan seismik rendah yang ditandai dengan nilai amplifikasi kurang dari tiga jika dibandingkan daerah lainnya. Geologi sisi utara lokasi penelitian tersusun oleh batuan gunung api dengan karakteristik batuan keras, ketebalan sedimen sangat tipis, dan tersusun atas batuan Tersier atau lebih tua. Peta kerentanan seismik berguna sebagai acuan dalam mitigasi gempa bumi untuk mengurangi risiko yang ditimbulkan. ABSTRACT Nusa Tenggara Barat (NTB) Province is an area with intense seismic activity. This phenomenon is caused by tectonic activity as the result of the convergency of the Eurasia-Australia Plates (subduction zone) in the south and the Flores Fault in the north as well as the presence of local faults. Regarding the plan to develop the Samota area in Sumbawa Island, NTB, a study concerning earthquakes should be done. The purpose of this study is to map the seismic vulnerability index (Kg) through microtremor measurement by using the Horizontal to Vertical Spectral Ratio (HVSR) analysis method. The result of the study is a seismic vulnerability map of the Plampang area which its northern part has a low seismic vulnerability index indicated by the amplification factor value of less than three compared to other areas. The geology of the northern part of the Plampang area consists of volcanic rocks which has hard rock characteristic, very thin sediment thickness, and composed of Tertiary or older rocks. Seismic vulnerability maps can be useful as a reference for earthquake mitigation to reduce its risks.

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Microtremor HVSR study of site effects in the urban area of the town of Mytilene, Lesvos (Greece) - Preliminary results.

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.10955 ◽

2016 ◽

Vol 47 (3) ◽

pp. 1081

Author(s):

E. Bouranta ◽

F. Vallianatos ◽

N. J. Hatzopoulos ◽

I. Papadopoulos ◽

P. Gaganis

Keyword(s):

Amplification Factor ◽

Spectral Ratio ◽

Predominant Frequency ◽

The North ◽

Soil Deposits ◽

North Aegean ◽

Microtremor Measurement ◽

The City ◽

The Town ◽

Microtremor Measurements

Mytilene is the capital of Lesvos, the eighth largest island in the Mediterranean Sea and the largest in the North Aegean. The region of North Aegean is a geotectonically complex area, because its geodynamic status is directly affected by the North Anatolian Fault Zone. In the present paper, microtremor data have been analyzedfor the city of Mytilene using Nakamura technique of Horizontal to Vertical Spectral Ratio (HVSR) to ascertain the structure in terms of the predominant frequency. 100 microtremor measurements have been performed in the city of Mytilene. At each point of microtremor measurement, the natural frequency and amplification factor have been determined. The predominant frequency varies from 0.4 Hz to 6.6 Hz. The amplification factor in 0.4-8.07 range has been obtained from the HVSR analysis. The results are presented in terms of maps, including the spatial variability of the predominant frequency and developed GIS database. The results of this study make it clear that the characteristics of microtremors depend on the type of soil deposits.

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LOCAL SEISMIC HAZARD ASSESSMENT OF THE MATARAM CITY, INDONESIA BASED ON SINGLE STATION MICROTREMOR MEASUREMENT

10.31227/osf.io/ghxed ◽

2018 ◽

Author(s):

Syamsuddin

Keyword(s):

Seismic Hazard ◽

Resonant Frequency ◽

Resonance Frequency ◽

Seismic Hazard Assessment ◽

Spectral Ratio ◽

Frequency Variation ◽

Single Station ◽

Noise Measurements ◽

Dominant Period ◽

Microtremor Measurement

Horizontal to vertical spectral ratio technique is used to assess the local seismic hazard through estimation of fundamental resonant frequency in Mataram city, Indonesia. In this study ambient noise measurements are carried out at 332 sites with the minimum duration of noise recording is about ten menit. Results of measurement indicate that the fundamental resonance frequency for Mataram range from 0.311 to 12,534 Hz. The resonance frequency variation showed a heterogeneous lithological conditions of the area. The resonant frequency is low or high are the dominant period in the western city of Mataram, while the resonant frequency high or low dominant periods are in the eastern. This means that the western region is very prone to earthquakes. In addition, there is a good correlation was found between Geology of Mataram city and HVSR results obtained in this research.

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Application of a GIS-based DRASTIC model and groundwater quality index method for evaluation of groundwater vulnerability: a case study, Sefid-Dasht

Water Science & Technology Water Supply ◽

10.2166/ws.2015.032 ◽

2015 ◽

Vol 15 (4) ◽

pp. 784-792 ◽

Cited By ~ 3

Author(s):

Nastaran Khodabakhshi ◽

Gholamreza Asadollahfardi ◽

Nima Heidarzadeh

Keyword(s):

Groundwater Quality ◽

Quality Index ◽

Major Ions ◽

Groundwater Vulnerability ◽

Vulnerability Index ◽

Aquifer Vulnerability ◽

Index Method ◽

Drastic Model ◽

Groundwater Quality Index ◽

The North

Pollution control and removal of pollutants from groundwater are a challenging and expensive task. The aims of this paper are to determine the aquifer vulnerability of Sefid-Dasht, in Chaharmahal and Bakhtiari province, Iran, using the DRASTIC model. In addition, the groundwater quality index (GQI) technique was applied to assess the groundwater quality and study the spatial variability of major ion concentrations using a geographic information system (GIS). The vulnerability index ranged from 65 to 132, classified into two classes: low and moderate vulnerability. In the southern part of the aquifer, the vulnerability was moderate. Furthermore, the results indicate that the magnitude of the GQI index varies from 92% to 95%. This means the water has a suitable quality. However, from the north to the south and southwest of the aquifer, the water quality has been deteriorating, and the highest concentration of major ions was found in the southwest of the Sefid-Dasht aquifer. A comparison of the vulnerability maps with the GQI index map indicated a poor relation between them. In the DRASTIC method, movement of groundwater is not considered and may be the reason for such inconsistency. However, the movement of groundwater can transport contaminants.

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Assessment of seismic hazard in the North Caucasus

Izvestiya Physics of the Solid Earth ◽

10.1134/s1069351307070051 ◽

2007 ◽

Vol 43 (7) ◽

pp. 559-572 ◽

Cited By ~ 16

Author(s):

V. I. Ulomov ◽

T. I. Danilova ◽

N. S. Medvedeva ◽

T. P. Polyakova ◽

L. S. Shumilina

Keyword(s):

Seismic Hazard ◽

North Caucasus ◽

The North

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The 2011 Oichalia (SW Peloponnese, Greece) seismic swarm: Geological and seismological evidence for E-W extension and reactivation of the NNW-SSE striking Siamo Fault

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.10927 ◽

2016 ◽

Vol 46 ◽

pp. 81 ◽

Cited By ~ 2

Author(s):

A. Ganas ◽

E. Lekkas ◽

M. Kolligri ◽

A. Moshou ◽

K. Makropoulos

Keyword(s):

Normal Fault ◽

Severe Damage ◽

Damage Distribution ◽

Field Orientation ◽

Axis Orientation ◽

Geological Evidence ◽

Seismic Swarm ◽

The North ◽

Seismological Data ◽

The Village

The Upper Messinia basin (Peloponnese, Greece) hosted a seismic swarm during the second half of 2011. The geological evidence (surface breaks striking N160°E), the seismological data (distribution of relocated earthquakes and T-axis orientation) and severe damage distribution are aligned along the eastern margin of the basin, so as they are attributed to reactivation of the bordering NNW-SSE normal fault. In particular, the rupture of the 14 August 2011 M=4.8 event is associated to the surface breaks inside the village Siamo. The length of the reactivated fault is estimated as 7 ±1 km based on the longest dimension (NW-SE) of the swarm epicentres (June to October 2011). The mode of rupture of the Siamo fault is probably related to a) the change in stress field orientation from south to north inside the basin (from E-W extension in the Siamo – Katsaro area to N-S extension in the north of Oichalia area) and/or b) to the occurrence of magmatic fluids due to the proximity of Messinia to the Hellenic subduction.

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Resonant Frequency Characteristics of a SAW Device Attached to Resonating Micropillars

Sensors ◽

10.3390/s120403789 ◽

2012 ◽

Vol 12 (4) ◽

pp. 3789-3797 ◽

Cited By ~ 20

Author(s):

N. Ramakrishnan ◽

Harshal B. Nemade ◽

Roy Paily Palathinkal

Keyword(s):

Resonant Frequency ◽

Frequency Characteristics

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Carbon Tariff vs. Emission Cap of North–South Countries in Response to Manufacturer’s Production

Sustainability ◽

10.3390/su12041443 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1443

Author(s):

Rui Dai ◽

Jianxiong Zhang ◽

Guowei Liu

Keyword(s):

Environmental Policies ◽

Well Being ◽

Differentiated Products ◽

Severe Damage ◽

The South ◽

Developed Country ◽

The North ◽

Stage Game ◽

Pareto Improving ◽

Carbon Tariff

Economy prosperity has concurrently caused severe emission damages worldwide, which calls for strong abatement efforts from both nations and manufacturers. In this paper, we establish a two-stage game to investigate the policy selections of a foreign developed country (North) and a domestic developing country (South), and the response of a Southern manufacturer. The welfare-maximizing governments in the two countries participate in an announcement game of environmental policies where the South decides on whether or not to enforce an emission cap and the North chooses either a carbon tariff or no policy, after which the profit-seeking manufacturer reacts to make production strategies and distribute differentiated products to the two countries. Our analysis shows that under an emission cap, the manufacturer shrinks product quantities in both markets, cuts emissions, and suffers profit losses. A carbon tariff has similar impacts on the manufacturer except for unaffected domestic sales. In addition, equilibrium policy selections for the two governments depend on the degree of emission damage in the South: A moderate level of damage generates an equilibrium in the scenario of the unilateral tariff policy where the Northern welfare peaks and the Southern well-being is not the worst; a severe damage leads to a prisoner’s dilemma, since the two governments would arrive at an equilibrium in the bilateral-policy scenario, but it is dominated by a no-policy scheme. What is more, we find that a negotiation between the two governments is able to help them out of the dilemma and achieve a Pareto-improving outcome.

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Peak ground acceleration at surface for Mataram city with a return period of 2500 years using probabilistic method

MATEC Web of Conferences ◽

10.1051/matecconf/201819503019 ◽

2018 ◽

Vol 195 ◽

pp. 03019

Author(s):

Rian Mahendra Taruna ◽

Vrieslend Haris Banyunegoro ◽

Gatut Daniarsyad

Keyword(s):

Seismic Hazard ◽

Return Period ◽

Peak Ground Acceleration ◽

Subduction Zones ◽

Amplification Factor ◽

Hazard Analysis ◽

Probabilistic Method ◽

Seismic Zone ◽

Ground Acceleration ◽

Back Arc

The Lombok region especially Mataram city, is situated in a very active seismic zone because of the existence of subduction zones and the Flores back arc thrust. Hence, the peak ground acceleration (PGA) at the surface is necessary for seismic design regulation referring to SNI 1726:2012. In this research we conduct a probabilistic seismic hazard analysis to estimate the PGA at the bedrock with a 2% probability of exceedance in 50 years corresponding to the return period of 2500 years. These results are then multiplied by the amplification factor referred from shear wave velocity at 30 m depth (Vs30) and the microtremor method. The result of the analysis may describe the seismic hazard in Mataram city which is important for building codes.

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Evaluation of Seismic Vulnerability Indices for Low-Rise Reinforced Concrete Buildings Including Data from the 6 February 2016 Taiwan Earthquake

Journal of Disaster Research ◽

10.20965/jdr.2020.p0009 ◽

2020 ◽

Vol 15 (1) ◽

pp. 9-19

Author(s):

Santiago Pujol ◽

Lucas Laughery ◽

Aishwarya Puranam ◽

Pedram Hesam ◽

Li-Hui Cheng ◽

...

Keyword(s):

Reinforced Concrete ◽

Seismic Vulnerability ◽

Vulnerability Index ◽

Exact Form ◽

Reinforced Concrete Buildings ◽

Severe Damage ◽

Concrete Buildings ◽

Damage And Failure ◽

Taiwan Earthquake

Communities need seismic vulnerability indices to identify which buildings are most susceptible to severe damage during earthquakes. To be of greatest value, these indices should be easy to use and should be vetted against data from previous earthquakes. To date, more than 800 reinforced concrete buildings have been surveyed after earthquakes for the purpose of evaluating a seismic vulnerability index proposed by Hassan and Sozen in 1997. This number includes 130 buildings surveyed after the 6 February 2016 earthquake in Taiwan. The data collected during these surveys consist of descriptions and photographs of damage, structural sketches, and measurements. Analyses of the data indicate that probability of severe damage and failure increases with decreasing column index and wall index (normalized measures of column and wall areas). They also suggest that the exact form of the threshold used to distinguish more vulnerable structures from less vulnerable structures is of little consequence in terms of the probable cost and benefits of the strengthening program this threshold may inform.

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