Mode of occurrence and thermo-remanent magnetization data of the Pliocene dacite pyroclastic deposits on Oyanoshima Island, Amakusa Islands, Kyushu, Japan

Table S1. Principal components of thermo-remanent magnetization identified by stepwise heating of the samples from locations 1–7.Fig. S1. Facies S1 exposed on the coast just east of the entrance to Shirato Inlet. (A) Close-up of fines-poor dacite lapillistone constituting the main part of Facies S1. Mechanical pencil for scale. (B) Clast-supported conglomerate sandwiched between fines-poor dacite lapilli tuff beds.Fig. S2. Facies S2 exposed on the coast just east of the entrance to Shirato Inlet (A, B) and 200 m east of this outcrop (C, D). (A) Laminated dacite tuff and lapilli tuff with a dune bedform 0.5–0.6 m thick. (B) Close-up of a dune bed showing the paleocurrent from right to left. (C) Bedded dacite lapilli tuff. Lithic lapilli ballistically emplaced into tuff layers. Hammer for scale. (D) Accretionary and armored lapilli in a normally graded bed 0.1 m thick.Fig. S3. Facies S3 exposed on the coast just east of the entrance to Shirato Inlet (A–C) and 200 m east of this outcrop (D). (A) Lapilli tuff beds of Facies S3, inversely to normally graded and accompanied by thin tuff layers. (B) Uppermost thin tuff layer and underlying lapilli tuff bed deformed by impact of lapilli. (C) Close-up view of B. Block-sag structure formed by emplacement of a ballistically ejected lithic lapillus. (D) Multiple lapilli tuff beds showing inverse to normal grading. Hammer and coin for scale.Fig. S4. Facies S4 exposed on the coast just east of the entrance to Shirato Inlet (A, B) and 200 m east of this place (C, D). (A) Non-stratified poorly sorted tuff breccia to lapilli tuff bed just overlying the lowermost locally cross-stratified. (B) Prismatically jointed dacite blocks. (C) Cauliflower bomb of poorly vesicular dacite. (D) Dacite block with jigsaw-fit cracks.Fig. S5. Facies K2 exposed along the coast 100–200 m east of the entrance to Kushi Inlet (A) and the coast just west of the inlet entrance (B-D). (A) Multiple beds of inversely to normally graded lapilli tuff to coarse tuff and wavy to parallel laminated fine-lapilli tuff to tuff, forming cross stratification. (B) Parallel to wavy or low-angle cross-laminated fine-lapilli tuff to tuff accompanied with a bed of inversely to normally graded lapilli tuff to coarse tuff. (C) Group of grey dacite fragments almost separated by jigsaw cracks in the graded lapilli tuff to coarse tuff. (D) Group of grey dacite fragments also separated but plastically deformed in the graded lapilli tuff to coarse tuff. Hammer and coin for scale.Fig. S6. Facies K3 exposed along the east coast of Kushi Inlet (A) and the west coast of the same inlet (B, C). (A) Facies K3 beds composed mainly of poorly sorted lapilli tuff with stratified tuff on top. Dacite breccias are intercalated between the beds. (B ) Armored lapilli in the lapilli tuff shown in Fig. 6D. (C) Accretionary lapilli in the stratified tuff layers shown in Fig. 6D. Hammer and coin for scale.Fig. S7. Facies K4 exposed on the west coast of Kushi Inlet (A, B) and the east coast of the same inlet (C, D). (A) Volcanic breccia to tuff breccia of Facies K4 unconformably overlying the stratified lapilli tuff of Facies K2. The facies boundary is sharp, plastically deformed and steeply inclined to the right (north). (B) A dacite blob-like block with many cracks extending into the interior. (C) Close-up of A showing jigsaw-fit dacite fragments almost separated by ash injection along the fractures. (D) Stratified lapilli tuff of Facies K2 enclosed in the poorly sorted, non-stratified tuff breccia to lapilli tuff of Facies K4. Person standing by the outcrop and hammer for scale.Fig. S8. Dacite intrusive rocks and clastic dikes exposed on the east coast of Kushi Inlet (A), the west coast of Kushi Hamlet (B and C), and the coast east of the entrance to Kushi Inlet (D). (A) Fluidal peperite produced along the surface of a dacite dike that intruded into Facies K4. (B) Dacite parallel dikes in the water-quenched and brecciated dacite lava. (C) Dacite lava comminuted and fluidized along the master cracks. (D) Clastic dike in Facies K4. Hammer for scale.Fig. S9. Variation in magnetization direction and intensity by stepwise heating of the samples from locations 1–7. Solid and open circles represent endpoints of magnetization vector projected onto the horizontal plane and the N-S vertical plane, respectively. Magnetization components on the horizontal plane are shown by red lines, in order to to make it easier to see how many components were obtained.Fig. S10. Characteristic remanent magnetization directions of dacite rock fragments from locations 1–7 and those of intrusive dacite specimens from locations OY3 and OY6, as determined by stepwise demagnetization.