Early Results of Eastern Indonesia P-wave Tomography Study Using Regional Events

The tectonic system of Eastern Indonesia is controlled by several major and minor plates, such as Indo-Australian, Australian plate, and Pacific plates. This area is known for its complexity, and high seismic activity. This study tries to image the complex structures beneath this region by employing regional events data and seismic tomography methods. We used five years of regional events catalog provided by the Indonesian Agency of Meteorology, Climatology, and Geophysics. We have sorted 7336 events recorded between 120° – 136° longitude and 0° – 13°(-) latitude consisting of 46446 P and 15467 S wave arrival data. Relocated hypocenter map shows a better constrain location on seismicity along outer Bandar Arc. A dipping pattern of seismicity is seen that is going deeper to the Banda Sea. The seismicity map also images a steep angle pattern of seismicity that could be related to the subduction slab roll-back model at North of Wetar island. Interestingly, we spotted a seismicity gap in West Seram that could be linked with slab tear zone. The checker-board test suggests a proper resolution is still reliable to a depth of 200 km with a less interpretable model at a depth of 300 km. P-wave tomographic models image the high velocity dipping down going slab. The Banda slab is seen to subduct from south Timor Island to the north, from east Tanimbar and Aru Island to west part, and from north Seram Island to south. We observed the down-going slab meet from all directions at about 300 km beneath the Banda sea. P wave tomogram also shows the Timor Island slab has a steeper dip that agrees with the seismicity pattern. Near the Seram island, we identify a low-velocity anomaly zone infiltrate the Banda slab beneath the shallow part of West Seram, which was previously interpreted as slab tear zone. This study also noticed a higher velocity tomogram model at North of Wetar island that might indicate a back-arc thrust. Lastly, a low-velocity band is also exposed at a shallow depth close to the volcano chain along that Banda volcanic arc.

Microzonation of Cisarua District Using Horizontal Vertical Spectral Ratio

The Bandung region is part of the framework of the Indonesian tectonic system, namely the tectonic plate meeting zone, where the Indo Autralia plate is infiltrated under the Eurasian plate in a convergent manner. The subduction process produces an effect in the form of an active fault geological structure in the Bandung area. One of these active faults is the Lembang Fault, which has a length of ± 29 kilometers and a shear acceleration of 3 to 5.5 millimeters per year. The microtremor measurement method is a passive geophysical method that utilizes natural subsurface vibrations so that it can provide dominant frequency data and amplification factors for soil layers. Based on the results of seismic susceptibility research using microtremor measurements using the HVSR method in the Lembang Fault zone in Cisarua Sub-District, it can be seen that the distribution of the dominant frequency values tends to be influenced by lithology and topography. In the research area, it is known to have a dominant frequency value that varies due to the different types of lithological units. In general, the dominant frequency ranges from 1-3 Hz because it is dominated by tuff sand and tuff pumice, and areas composed of volcanic breccias have a dominant frequency value between 3-6 Hz. Meanwhile, the amplification factor value will be influenced by rock deformation and weathering. The area that has a very high amplification factor value is in the southeast of the study area with an A0 value greater than 5. This indicates that the area is composed of a layer of thick and not dense tuff sand

SALT WELDING DURING CANOPY ADVANCE AND SHORTENING IN THE GREEN CANYON AREA, NORTHERN GULF OF MEXICO

Welds form due to the tectonically-induced thinning and/or dissolution of salt, with their composition and completeness thought to at least partly reflect their structural position within the salt-tectonic system. Despite their importance as seals or migration pathways for accumulations of hydrocarbons and CO2, we have relatively few examples of drilled subsurface welds; such examples would allow us to improve our understanding of the processes and products of welding, and to test analytical models of the underlying mechanics. In this study we integrate 3D seismic reflection and borehole data from the Green Canyon Area of the northern Gulf of Mexico, USA to characterize the geophysical and geological expression of a tertiary weld, as well as its broader salt-tectonic context. These data show although it appears complete on seismic reflection data, the weld contains 124 ft (c. 38 m) of pure halite. This thickness is consistent with the predictions of analytical models, and with observations from other natural examples of subsurface welds. Our observations also support a model whereby compositional fractionation of salt occurs as the salt-tectonic system evolves; in this model, less mobile and/or denser units are typically stranded within the deeper, autochthonous level, trapped in primary welds, or stranded near the basal root of diapirs, whereas less viscous and/or less dense units form the cores of these diapirs and, potentially, genetically related allochthonous sheets and canopies. We also show that shearing of the weld during downslope translation of the overlying minibasin did not lead to complete welding.

Konsep Penataan Ruang Kawasan Rawan Bencana (KRB) Tsunami di Kabupaten Karangasem, Pulau Bali

The island of Bali and its surrounding are part of Indonesia's seism tectonic system. The condition has been faced including by Karangasem Regency. Karangasem Regency is prone by seismic and tsunami disaster. The high level of disaster proneness in Karangasem Regency requires disaster preparedness in pre-disaster phase. Rehabilitation and reconstruction responses are not been effective since these steps require expensive funding and investment. Preparedness efforts in pre-disaster phase are carried out through quality enhancement of spatial plans based on Disaster Risk Reduction (DRR). This research is aimed to provide recommendation for spatial plan, including spatial pattern (land use) plan and development of mitigation infrastructure. This research uses qualitative and quantitative research methods. Analysis tools are Geographic Information Systems (GIS), good practices, and literatures, as well as policies from various sources. The output of this study resulted in a spatial assessment according to the level of tsunami disaster prone level.

Geochemistry of the black rock series of lower Cambrian Qiongzhusi Formation, SW Yangtze Block, China: Reconstruction of sedimentary and tectonic environments

The black rock series in the Qiongzhusi Formation contains important geochemical information about the early Cambrian tectonic and ecological environment of the southwestern Yangtze Block. In this paper, major, trace, and rare earth element data are presented in an attempt to reveal the sediment source during the deposition of the early Cambrian Qiongzhusi Formation and to reconstruct the sedimentary tectonic environment and weathering intensity during that time. The basin primarily received continental clastic material with neutral-acidic igneous rocks from a stable source and with a moderate level of maturity during the depositional period of the Qiongzhusi Formation. Furthermore, the strata were weakly influenced by submarine hydrothermal fluids during diagenesis. The reconstruction of the sedimentary environment and weathering intensity shows that P2O5 enrichment and water body stratification occurred due to the effects of upwelling ocean currents during the depositional period of the Qiongzhusi Formation. The combination of upwelling and bottom-water hydrothermal fluids led to environmental changes in the study area, from dry and hot to moist and warm. Last, the reconstruction of the tectonic environment of the Qiongzhusi Formation indicates that deposition occurred in continental slope and marginal marine environments associated with a continental arc tectonic system. These findings provide an essential basis for the comprehensive reconstruction of the early Cambrian sedimentary environment of the Yangtze Block.

Urban integration - MIA Dorćol, Belgrade

The effort to recreate the continuity of values in the existing context, both in terms of architecture and always inextricably linked to it and in the cultural sense, is realized through honesty. Honesty actually means achieving a relationship between the functional and tectonic system of the object itself and its appearance through an understanding of the spatial-semantic multidimensionality of the context. The semantic, dialogical and dualistic principles of contextualization, which ultimately has the true three-dimensionality of the facade itself, and which arose from the system and function of the building, established the identity and value continuity of architectural heritage, created during the industrialization of Belgrade and Serbia.

Adaptive kinematic textile architecture

The research presented in this paper explores how textiles can be formed into adaptive, kinematic spaces to be able to respond to its environment and users utilizing on-site, distributed, mobile robotic connectors. The project aimed at creating an adaptive system that consumes little energy while making use of textiles’ advantageous qualities—their lightweight, portability, and manipulability. This was achieved through the development of a bespoke on-material mobile machine able to locomote on suspended sheets of fabrics while shaping them. Together, the connector and the tectonic system compose a lightweight architectural robot controlled with a feedback loop that evaluates real-time environmental sensor data from the space against user-defined targets. This research demonstrates how the combination of mobile robotics and textile architecture opens up new design possibilities for adaptive spaces by proposing a system that is able to generate a significant architectural effect with minimal mechanical actuation.