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Daerah Mamuju dan sekitarnya umumnya disusun oleh batuan gunung api. Batuan sedimen vulkanoklastik dan batugamping berada di atas batuan gunung api. Aktivitas gunung api membentuk beberapa morfologi unik seperti kawah, kubah lava, dan jalur hembusan piroklastika sebagai produknya. Produk tersebut diidentifikasi berdasarkan karakter bentuk-bentuk melingkar di citra Landsat-8. Hasil koreksi geometrik dan atmosferik, interpretasi visual pada citra Landsat-8 dilakukan untuk mengidentifikasi struktur, geomorfologi, dan kondisi geologi daerah tersebut. Struktur geologi regional menunjukkan kecenderungan arah tenggara – baratlaut yang mempengaruhi pembentukan gunung api Adang. Geomorfologi daerah tersebut diklasifikasikan menjadi 16 satuan geomorfologi berdasarkan aspek genetisnya, yaitu punggungan blok sesar Sumare, punggungan kuesta Mamuju, kawah erupsi Adang, kawah erupsi Labuhan Ranau, kawah erupsi Sumare, kerucut gunung api Ampalas, kubah lava Adang, bukit intrusi Labuhan Ranau, punggungan aliran piroklastik Adang, punggungan aliran piroklastik Sumare, perbukitan sisa gunung api Adang, perbukitan sisa gunung api Malunda, perbukitan sisa gunung api Talaya, perbukitan karst Tapalang, dan dataran aluvial Mamuju, dataran teras terumbu Karampuang. Berdasarkan hasil interpretasi citra Landsat-8 dan konfirmasi lapangan, geologi daerah Mamuju dibagi menjadi batuan gunung api dan batuan sedimen. Batuan gunung api terbagi menjadi dua kelompok, yaitu Kompleks Talaya dan Kompleks Mamuju. Kompleks Talaya terdiri atas batuan gunung api Mambi, Malunda, dan Kalukku berkomposisi andesit, sementara Kompleks Mamuju terdiri atas batuan gunung api Botteng, Ahu, Tapalang, Adang, Ampalas, Sumare, dan Labuhan Ranau berkomposisi andesit sampai basal leusit. Vulkanostratigrafi daerah ini disusun berdasarkan analisis struktur, geomorfologi, dan distribusi litologi. Vulkanostratigrafi daerah Mamuju diklasifikasikan ke dalam Khuluk Talaya dan Khuluk Adang. Khuluk Talaya terdiri atas Gumuk Mambi, Gumuk Malunda, dan Gumuk Kalukku. Khuluk Mamuju terdiri atas Gumuk Botteng, Gumuk Ahu, Gumuk Tapalang, Gumuk Adang, Gumuk Ampalas, Gumuk Sumare, dan Gumuk Labuhan Ranau. Mamuju and its surrounding area are constructed mainly by volcanic rocks. Volcanoclastic sedimentary rocks and limestones are laid above the volcanic rocks. Volcanic activities create some unique morphologies such as craters, lava domes, and pyroclastic flow paths as their volcanic products. These products are identified from their circular features characters on Landsat-8 imagery. After geometric and atmospheric corrections had been done, a visual interpretation on Landsat-8 imagery was conducted to identify structure, geomorphology, and geological condition of the area. Regional geological structures show trend to southeast – northwest direction which is affects the formation of Adang volcano. Geomorphology of the area are classified into 16 geomorphology units based on their genetic aspects, i.e Sumare fault block ridge, Mamuju cuesta ridge, Adang eruption crater, Labuhan Ranau eruption crater, Sumare eruption crater, Ampalas volcanic cone, Adang lava dome, Labuhan Ranau intrusion hill, Adang pyroclastic flow ridge, Sumare pyroclastic flow ridge, Adang volcanic remnant hills, Malunda volcanic remnant hills, Talaya volcanic remnant hills, Tapalang karst hills, Mamuju alluvium plains, and Karampuang reef terrace plains. Based on the Landsat-8 imagery interpretation result and field confirmation, the geology of Mamuju area is divided into volcanic rocks and sedimentary rocks. There are two groups of volcanic rocks; Talaya complex and Mamuju complex. The Talaya complex consists of Mambi, Malunda, and Kalukku volcanic rocks with andesitic composition, while Mamuju complex consist of Botteng, Ahu, Tapalang, Adang, Ampalas, Sumare, danLabuhanRanau volcanic rocks with andesite to leucitic basalt composition. The volcanostratigraphy of Mamuju area was constructed based on its structure, geomorphology and lithology distribution analysis. Volcanostratigraphy of Mamuju area is classified into Khuluk Talaya and Khuluk Mamuju. The Khuluk Talaya consists of Gumuk Mambi, Gumuk Malunda, and Gumuk Kalukku, while Khuluk Mamuju consists of Gumuk Botteng, Gumuk Ahu, Gumuk Tapalang, Gumuk Adang, Gumuk Ampalas, Gumuk Sumare, and Gumuk Labuhan Ranau.

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The Tertiary stratigraphy of Situbondo was constructed by a series of volcanoclastic-carbonate turbidite facies of Menuran Formation with Pacalan limestone Member, and Leprak Formation. These formations formed a regional east-west trending circular anticlinorium. The Tertiary formations were covered by Quaternary volcano-clastic Ringgit Formation and subsequent younger Bagor volcanic products. The oldest Tertiary rock units are the Late Miocene-Pliocene Menuran Formation, with Pacalan Limestone Member. Formation is mainly composed of foram-rich marls and calcareous, sometimes tuffaceous sandstones, with conglomerate intercalations. Sedimentation of this formation is interpreted as to be a mixing, from proximal to distal turbidite, involving volcaniclastic and carbonate sources, in  a bathyal open marine environment. The Early Pliocene Leprak Formation overlies conformably the Menuran Formation, which consists of alternating calcareous sandstones and tuff sandstones deposited in a bathyal open marine environment with proximal turbidite mechanism suggesting that basin depocenter was located to the east. Up to Late Pliocene, the region was dominated by developments proximal turbidite volcanoclastic sedimentation of The Leprak Formation, contemporaneous with increasing volcanic activity in the south. Deformation of Plio-Pleistocene in Java is believed to be the last major tectonic period, which forms the west-east trending structures. In Situbondo area, folding structures in this direction involves the Neogene Menuran Formation, Pacalan Member and Leprak Formation. Volcanic activity persists, and increases, with the activity of Ringgit-Beser volcano in Pleistocene. These late events of magmatism, volcanism and uplift were contributed to the last structural configuration of the area.Keyword : Situbondo, structural geology, volcanic-kendeng zone, stratigraphy