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Surface exposure ages of marine and fluvial terraces based on in situ 10Be dating were determined to estimate formation ages and long-term rates of coastal uplift along the northern Pacific coast of Northeastern Japan. Surface rock samples were collected along the northern and southern coasts of Sanriku based on a reinterpretation of dispersed marine and fluvial terraces using DEM and aerial photographs. We collected three samples at the Samuraihama site from outcrops of pairs of marine and fluvial terraces distributed over the east-facing flank of the Kitakami Mountains. At the Yoshihama site, in contrast, where bedrock surfaces could be better exposed, we took vertical samples from weathered granite rocks on small trench walls dug on the middle marine terrace at Yoshihama Bay. Surface exposure ages from 10Be concentrations in quartz calculated from the measured 10Be/9Be ratios commonly suggest slow in both sites, whereas steep (~ 10°) dip domains on the marine terraces along the northern Sanriku coast may imply localized permanent strain accumulation.

Precise levelling surveys were conducted across the central Longitudinal Valley Fault, eastern Taiwan, to understand the deformation of the transition zone between the stable fault creep area and the asperity area. In order to investigate the surface relationship between the fault creep area and the geological condition of the transition zone, we established levelling routes in the Yuli, Chike-san, and Reishuei areas. The Yuli area forms the geological boundary of the Lichi Melange Formation, which is composed of chaotic mudstones containing numerous exotic blocks of various sizes and lithologies. Along the Yuli route, located on the Lichi Melange, an uplift rate of 30 mm/yr was detected during the period 2010–2012, suggesting that aseismic fault creep might be continuing with long-term stability. Along the Chike-san route, a vertical deformation rate of 8 mm/yr was detected in the period 2010–2011. However, a large deformation with an uplift rate of 40 mm/yr was detected in the period 2011–2012. Along the Reisuei route, we detected a deformation of 8 mm/yr in the period 2011–2012. A two-dimensional single-fault model was developed to discuss the slip distributions in the periods 2010–2011 and 2011–2012. Relatively large slip rates were estimated at two parts of the fault plane—one at a depth of ~ 1.5 km and another at a depth of ~ 4 km—in both periods. Because both parts of the fault plane show approximately the same slip distribution, we believe that the detected deformation resulted from an episodic acceleration event of creeping slip. The northern limit of the stable creep area may be the Yuli area. The episodic creep event occurred in the transition zone between the stable fault creep area and the asperity area. The boundary between the stable creep area and the episodic creep area is consistent with the geological boundary of the Lichi Melange Formation.

We perform terrestrial laser scanning (TLS) to detect changes in surface morphology of a mud volcano in Murono, north-central Japan. The study site underwent significant deformation by a strong earthquake in 2011, and the surface deformation has continued in the following years. The point cloud datasets were obtained by TLS at three different times in 2011, 2013 and 2014. Those point clouds were aligned by cloud-based registration, which minimizes the closest point distance of point clouds of unchanged ground features, and the TLS-based point cloud data appear to be suitable for detecting centimeter-order deformations in the central domain of the mud volcano, as well as for measurements of topographic features including cracks of paved ground surface. The spatial patterns and accumulative amount of the vertical deformation during 2011–2014 captured by TLS correspond well with those previously reported based on point-based leveling surveys, supporting the validity of TLS survey.

Lanyu and Lutao Islands to the southeast of Taiwan are located in the northern extension of the Luzon Arc. Crustal deformation of these islands provides a key to understand the collision of the Luzon Arc against Taiwan. To clarify the style and the rate of vertical movement during the Holocene, uplifted coral reefs fringing these two islands were investigated. Living corals were also investigated for comparison with fossil corals. It was found that Isopora palifera lives dominantly in the upper slope of the present-day fringing coral reefs in Lanyu Island at an average depth of 101 ± 46 cm (one standard deviation) below mean sea level. Using I. palifera as an accurate indicator of paleo-sea levels, Holocene relative sea-level changes were reconstructed. Lanyu Island has been uplifted continuously at a rate of 2.0 mm yr−1, at least during the late Holocene from 2,269 cal. yr BP to the present. Lutao Island has been uplifted at an average rate of 1.2 mm yr−1, since at least 5,749 cal. yr BP, although it is unclear whether the uplift was continuous. The present observations, combined with the GPS displacement field and deep crustal structure, suggest that the continuous uplift is related to aseismic slip on the Longitudinal Valley Fault.

We find three coral boulders (approx. 5 m across) resting on the Holocene coral terrace on the Jiupeng coast of southeastern Taiwan. Three exotic corals on the outer part of the boulders are dated at ca. 5000 yr BP which is similar to that of in situ corals composing the Holocene terrace. We interpret that these boulders were broken off from the coral terrace and were transported by tsunami waves, although the timing of the paleotsunami is not determined at this stage.

This paper reports on the trench log data covering the Chelungpu Fault preserved at the National Science Museum and 10 bore hole data across the fault. Trench log indicates the vertical offset of the 1999 displacement of terrace deposits is ca. 1.5 m and the presence of four branch faults cutting terrace deposits within 1.8 m width zone. Estimated height difference of bedrock surface based on bore hole data is more than 4.2 - 5.8 m, larger than the offset by the 1999 earthquake. These facts imply that at least one earthquake event occurred at this site before the 1999 earthquake. We also estimate the fault plane dips eastward at about 30 degrees based on the location and stratigraphy of one bore hole which penetrates the terrace gravel on the hanging wall through the bedrock.