Perbandingan Analisis Distribusi Ukuran Butir Menggunakan Metode Momen dan Metode Grafis pada Sedimen Sungai Progo dan Sungai Bogowonto
Abstract
Abstrak – Analisis distribusi ukuran butir sedimen dapat dilakukan secara statistik menggunakan metode momen dan metode grafis. Analisis ukuran butir pada sedimen Sungai Progo dan Sungai Bogowonto dilakukan untuk mendapatkan parameter berupa ukuran butir rata-rata, sortasi, skewness, dan kurtosis. Aplikasi dua metode berbeda memungkinkan munculnya hasil nilai numerik maupun terminologi deskriptif yang berbeda untuk setiap parameter ukuran butir. Sampel sedimen Sungai Progo mayoritas menunjukkan distribusi ukuran butir unimodal, sedangkan sedimen Sungai Bogowonto didominasi oleh distribusi bimodal. Parameter ukuran butir dari sampel Sedimen Sungai Progo lebih banyak memiliki kesamaan secara terminologi deskriptif dari dua metode yang digunakan dibandingkan dengan sedimen dari Sungai Bogowonto. Parameter ukuran butir rata-rata dan sortasi tidak terlalu dipengaruhi oleh distribusi ukuran butir, sehingga terminologi deskriptif yang dihasilkan dari analisis distribusi ukuran butir cenderung memiliki kesamaan antara metode momen dan metode grafis. Parameter skewness, diikuti parameter kurtosis merupakan parameter yang paling terpengaruh oleh distribusi ukuran butir, ditunjukkan oleh perbedaan hasil parameter ukuran butir sedimen Sungai Progo dan Sungai Bogowonto.
Kata Kunci: Distribusi ukuran butir, Metode Momen, Metode Grafis, Sungai Progo, Sungai Bogowonto.
Abstract – Grain size distribution analysis of sediments can be done statistically using the moment and graphical methods. Grain size analysis in the Progo and Bogowonto Rivers sediments was carried out to obtain parameters such as average grain size, sorting, skewness, and kurtosis. Applying two different methods allows the emergence of different numerical values and descriptive terminology for each grain size parameter. Most of the Progo River sediment samples showed a unimodal grain size distribution, while a bimodal distribution dominated the Bogowonto River sediments. The grain size parameters of the Progo River sediment samples have more in common regarding the descriptive terminology of the two methods than the sediments from the Bogowonto River. The parameters of the average grain size and sorting are not significantly affected by the grain size distribution, so the descriptive terminology resulting from the grain size distribution analysis tends to have similarities between the moment and the graphical methods. The skewness parameter, followed by the kurtosis parameter, is the parameter most affected by the grain size distribution, shown by the difference in the results of the grain size parameter of the Progo River and Bogowonto River sediments.
Keywords: Grain size distribution Moment method, Graphical method, Progo River, Bogowonto River.
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DOI: https://doi.org/10.31315/jigp.v9i1sp.9416
DOI (PDF (Bahasa Indonesia)): https://doi.org/10.31315/jigp.v9i1sp.9416.g5229
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