Analisis Komponen Volatil Dan Laju Alir Lava Pada Erupsi Gunung Semeru, Jawa Timur

Gunung Semeru merupakan salah satu gunung aktif di Indonesia dan telah mengalami Perubahan tipe erupsi sejak tahun 1967. Sehingga penting untuk dilakukan penelitian mengenai analisis erupsi berdasarkan komponen volatil dan penentuan laju alir lava Gunung Semeru dengan tujuan untuk memperkirakan mekanisme sifat erupsi pada masa sekarang dan untuk mengetahui potensi daerah berbahaya aliran lava G. Semeru bila terjadi letusan eksplosif.Analisis erupsi didasarkan pada parameter fisika terhadap analisis geokimia batuan sedangkan laju alir lava didasarkan pada kemiringan topografi yang dilaluinya. Hasil penelitian menunjukkan berkurangnya tekanan akan mengakibatkan lepasnya gas dari magma dengan cepat, Hal ini memicu terjadinya sifat hembusan. Daerah yang memiliki laju alir lava G. Semeru paling cepat adalah Desa Oro oro Ombo, Kecamatan Pronojiwo, Kabupaten Lumajang

Identifikasi Kantung Magma Gunung Bromo Berdasarkan Analisa Sebaran Hiposenter Gempa VTA

Gunung Bromo merupakan salah satu dari serangkaian gunungapi aktif di Indonesia yang terletak di dalam kaldera Tengger, Kabupaten Probolinggo, Jawa Timur. Dalam sejarahnya, tercatat bahwa Gunung Bromo telah mengalami lebih dari 50 kali erupsi sejak tahun 1775. Penellitian guna mengetahui geometri dari kantung magma Gunung Bromo telah dilakukan dengan menganalisa sebaran hiposenter gempa vulkanik dalam (VTA). Gempa VTA merupakan gempa yang terjadi di gunungapi yang disebabkan oleh proses pergerakan magma di kantung magma. Penelitian dilakukan terhadap data rekaman seismik Bromo pada bulan Februari – Maret 2014. Penentuan posisi hiposenter dilakukan dengan metode GAD. Hasil penelitian menunjukkan bahwa hiposenter gempa VTA tersebar di bawah kawah Bromo dengan kedalaman ± 2 km – 15 km dari puncak kawah Bromo. Selain itu, titik episenter tersebar dengan radius ± 25 m dari pusat kawah pada arah Timur Laut-Baratdaya. Posisi hiposenter gempa mengindikasikan bahwa Gunung Bromo memiliki 2 (dua) buah kantung magma dengan ukuran berbeda. Kantung magma dangkal dengan ukuran lebih kecil berada di kedalaman sekitar 2 km hingga 5 km dari puncak yang ditunjukkan oleh sebaran hiposenter yang rapat. Sedangkan kantung magma yang lebih besar berada di kedalaman sekitar 7 km hingga 15 km dari puncak Bromo

Assessment of spatiotemporal variability of meteorological droughts in northern Iraq using satellite rainfall data

The absence of a dense rainfall monitoring network and longer period data are the major hindrances of hydroclimatic study in arid and semi-arid regions. An attempt has been made for the evaluation of spatiotemporal changes in droughts at the northern semi-arid region of Iraq for the period 1981–2018 using high-resolution (0.05°) precipitation data of Climate Hazards Group Infrared Precipitation with Stations (CHIRPS). The performance of CHIRPS in replicating rainfall and Standard Precipitation Index (SPI) for different timescales at eleven locations for the available period of observation data (2000–2014) was evaluated. The SPI was also used to estimate drought frequency and evaluate drought trends at all the CHIRPS grid points. A modified version of the non-parametric Mann-Kendall (MK) test was employed for a robust evaluation of the spatial distribution of temporal trends in droughts. The results showed a good ability of CHIRPS in reconstructing observed SPI with a correlation coefficient ranged from 0.64 to 0.87, BIAS between 1.05 and 1.81, Nash-Sutcliff efficiency from 0.39 to 0.55, and Willmott Index between 0.67 and 0.79. The CHIRPS also able to reconstruct the time series and probability distribution of observed SPI reasonably. Spatial distribution of droughts revealed a higher frequency of droughts of all categories and timescales in the east and north of Northern Iraq, mainly due to high rainfall variance. The MK test revealed a reduction in 6- and 12-month droughts in the northwest and an intensification at a few northeastern grids. It indicates droughts became more recurrent in the already drought-prone region and lessened in a less drought-prone region

A New Bayesian Network-Based Generalized Weighting Scheme for the Amalgamation of Multiple Drought Indices

Drought is one of the most multifaceted hydrologic phenomena, affecting several factors such as soil moisture, surface runoff, and significant water shortages. Therefore, monitoring and assessing drought occurrences based on a single drought index are inadequate. The current study develops a multiscalar weighted amalgamated drought index (MWADI) to amalgamate multiple drought indices. The MWADI is mainly based on the normalized average dependence posterior probabilities (ADPPs). These ADPPs are obtained from Bayesian networks (BNs)-based Markov Chain Monte Carlo (MCMC) simulations. Results have shown that the MWADI correlates more with the standardized precipitation index (SPI) and the standardized precipitation temperature index (SPTI). As proposed, the MWADI synthesizes drought characteristics of different multiscalar drought indices to reduce the uncertainty of individual drought indices and provide a comprehensive drought assessment.Validerad;2023;Nivå 2;2023-05-04 (hanlid);Funder: Deanship ofScientifc Research at King Khalid University  (RGP.2/23/44); Prince Sattam bin Abdulaziz University (PSAU/2023/R/1444);Part of special issue: Technologies-Based Advanced Machine Learning Models: Applications in Civil Engineering 2021</p

Abstracts of 1st International Conference on Computational & Applied Physics

This book contains the abstracts of the papers presented at the International Conference on Computational &amp; Applied Physics (ICCAP’2021) Organized by the Surfaces, Interfaces and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria, held on 26–28 September 2021. The Conference had a variety of Plenary Lectures, Oral sessions, and E-Poster Presentations. Conference Title: 1st International Conference on Computational &amp; Applied PhysicsConference Acronym: ICCAP’2021Conference Date: 26–28 September 2021Conference Location: Online (Virtual Conference)Conference Organizer: Surfaces, Interfaces, and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria