Penelitian ini berlokasi di daerah Kalan, Kabupaten Melawi, Kalimantan Barat. Batuan Metamorf Pinoh merupakan litologi dominan yang terbentuk pada Pegunungan Schwaner. Batuan Metamorf Pinoh merupakan formasi batuan yang berumur tua, yakni berumur Trias. Batuan Metamorf di daerah Kalan memiliki kajian menarik untuk dilakukan penelitian, karena didapatkan mineralisasi unsur radioaktif. Terbentuknya mineralisasi unsur radioaktif berkaitan dengan protolith dan fasies metamorfime (proses suhu dan tekanan). Untuk mengkaji penelitian ini, digunakan beberapa metode penelitian. Metode penelitian yang digunakan adalah pengukuran radiometrik, analisis petrologi, analisis geokimia, dan analisis petrografi. Metode-metode tersebut di korelasikan sehingga mendapatkan kesimpulan protolith dan fasies metamorfismenya. Daerah Kalan ditemukan protolith berupa batuan pelitik dan batuan kuarsa-feldspatik. Fasies metamorfisme yang terjadi adalah fasies sekis hijau yang dicirikan dengan ditemukan mineral klorit, aktinolit, muskovit, biotit, kuarsa, hingga garnet.

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This study is located in the Kalan area, Melawi Regency, West Kalimantan. Pinoh Metamorphic Rocks are the dominant lithology formed in the Schwaner Mountains. Pinoh Metamorphic Rock is an old rock formation, which is Triassic in age. Metamorphic rocks in the Kalan area have interesting studies to conduct research, because radioactive element mineralisation was obtained. The formation of radioactive element mineralisation is related to protoliths and metamorphism facies (temperature and pressure processes). To study this research, several research methods were used. The research methods used are radiometric measurements, petrological analysis, geochemical analysis, and petrographic analysis. These methods are correlated to get the conclusion of protoliths and metamorphism facies. The Kalan area found protoliths in the form of pelitic rocks and quartz-feldspathic rocks. The metamorphism facies that occurs is the green schist facies characterised by the discovery of chlorite, actinolite, muscovite, biotite, quartz, and garnet minerals.