ABSTRAK

INTERPRETASI DATA WELL LOGGING UNTUK MENENTUKAN LAPISAN AKUIFER  DI KABUPATEN HULU SUNGAI UTARA, KALIMANTAN SELATAN

 (Oleh : Hudchon Doyo Hastomo; Sri Cahyo Wahyono, S.Si., M.Si.;  Simon Sadok Siregar, S.Si., M.Si ; 2023 ; 55 halaman)

Penelitian interpretasi data Well Logging untuk menentukan lapisan akuifer  telah dilakukan di Kabupaten Hulu Sungai Utara Kalimantan Selatan. Metode yang digunakan yaitu mengolah 12 data Well Logging resistivitas dan gamma ray menggunakan software wellcad untuk mendapatkan nilai log gamma, log resisitivity serta kurva gamma ray dan resistivitas dalam bentuk 1D sehingga diketahui litologi bawah permukaan di daerah tersebut, selanjutnya dilakukan interpolasi menggunakan software hydrogeoanalyst untuk mendapatkan model penampang 2D dan 3D sehingga diketahui jenis lapisan akuifer dan sebaran akuifer di daerah penelitian. Hasil pengolahan data menunjukkan bahwa terdapat 4 lapisan batuan yaitu lempung, lempungan pasiran, pasir, dan batubara  dengan sifat batuan akuiklud, akuitar, akuifer dan akuifug. Dari interpretasi litologi yang telah dilakukan dapat diklasifikasikan jenis akuifer yang terdapat pada masing-masing 16 titik sumur, terdapat 2 jenis akuifer yaitu : akuifer bebas dan tertekan. Sebaran akuifer pada penelitian ini menunjukkan potensi akuifer tertekan dengan ketebalan terbesar sampai terkecil masing masing secara berurutan yaitu pada Sumur 2 (48,5 m ) – Sumur 12 ( 47 m) – 10 (45,5) – Sumur 4 (44 m) – Sumur 11 (42 m), – Sumur 8 (41,5 m ) – Sumur 3 (38,5 m) –  Sumur 5 (37 m) – Sumur 7 (26,5) – Sumur 6 (30,75 m) – Sumur 1 (28 m), – Sumur 9 (19,5 m ). Sehingga secara keseluruhan dapat disimpulkan bahwa di Kabupaten Hulu Sungai Utara memiliki potensi air tanah dalam yang cukup besar karena terdapat banyak lapisan pasir.

Kata Kunci : akuifer, gamma ray, resistivitas, Well Logging.

ABSTRACT

INTERPRETATION OF WELL LOGGING DATA TO DETERMINE AQUIFER LAYERS IN HULU SUNGAI UTARA DISTRICT, SOUTH KALIMANTAN

(By : Hudchon Doyo Hastomo; Sri Cahyo Wahyono, S.Si., M.Sc.; Simon Sadok Siregar, S.Si., M.Si ; 2023 ; 55 pages)

Research on interpretation of Well Logging data to determine aquifer layers has been carried out in Hulu Sungai Utara District, South Kalimantan. The method used is to process 12 resistivity and gamma ray Well Logging data using WellCAD software to obtain gamma log, resistivity log and gamma ray and resistivity curves in 1D form so that the subsurface lithology in the area is known, then interpolation is carried out using hydrogeoanalyst software to obtain 2D and 3D cross-sectional models so that the types of aquifer layers and distribution of aquifers in the study area are known. The results of data processing show that there are 4 layers of rock, namely clay, sandy loam, sand, and coal with the rock properties of aquicludes, aquitars, aquifers and, aquifers. From the lithological interpretation that has been carried out, it can be classified the types of aquifers that are found at each of the 16 well points, there are 2 types of aquifers, namely: free and confined aquifers. The distribution of aquifers in this study shows the potential for aquifers under pressure with the largest to smallest thickness respectively, namely Well 2 (48.5 m) – Well 12 (47 m) – 10 (45.5) – Well 4 (44 m) – Well 11 (42 m), – Well 8 (41.5 m ) – Well 3 (38.5 m) – Well 5 (37 m) – Well 7 (26.5) – Well 6 (30.75 m) – Well 1 (28 m), – Well 9 (19.5 m ). So as a whole it can be concluded that Hulu Sungai Utara Regency has a large potential for deep groundwater because there are many layers of sand.

Keywords: aquifer, gamma ray, resistivity, Well Logging.