No abstract

Used tyres interact with soil, water and the atmosphere during temporary or permanent storage and also when used as additive or paving materials in landscapes, asphalt, concrete and for coastal protection. Various organic and inorganic compounds can penetrate into the environment from used tyres at various rates dependent on climatic and soil conditions. In this study, laboratory leaching batch experiments were conducted to determine the heavy metals and other constituents that could possibly penetrate into the leachate created during tyre usage/storage. The results obtained in this study showed that tyres were dissolved due to their usage and the climatic and environmental conditions thus leading to soil and groundwater pollution in their usage/reuse/storage/disposal areas. Zinc concentrations were the highest among the heavy metals measured in the simulated leachate. The average weight loss for all tyre samples was calculated as 3.6‰.

Armutlu Peninsula is in the Marmara Region of Turkey, located at the western end of the 1999 Kocaeli rupture. Armutlu peninsula is believed to be adjacent to the Intra-Pontide Suture Zone, or even to be a part of it. This zone has a key role for the understanding of the neo-tectonic features of this region and the interactions between high seismicity with high thermal activity and neo-tectonic faults that have originated through the ongoing movement of the two branches north and south of Armutlu. A horst and graben structure appears in this region, whereby the Armutlu Peninsula represents a horst between two branches of the North Anatolian Fault System, which results in a complex dextral zone. To understand the relationships among the micro-earthquake activity, the hydrothermal activity, and the tectonic structure of the region, the Armutlu Network (ARNET) was installed. ARNET aims to monitor the chronological evolution of the seismicity, and to investigate the deformation of the Armutlu Peninsula, and possible interactions between seismic waves and pore-pressure variations in the geothermal systems. The Armutlu-Yalova-Gemlik region has a very complicated tectonic structure, and it has scattered micro-earthquake activity. The upper part of the crust includes a low-velocity zone that conforms to present tectonic activity and the brittle deformed metamorphic rocks. Recent seismic activity has been confined to Gemlik Bay, and the Yalova-Termal region. Therefore, special attention is needed to monitor the seismic activity in these regions, to understand the likely and forthcoming larger event(s) in the Marmara Region. We believe that this region will have an important role in our understanding of the formation of the next larger earthquake at the western extension of the North Anatolian Fault system.

Earthquake early warning systems aim to reduce the potential danger by providing a warning in the seconds before strong ground shaking occurs. In this study, we implemented EPIC, an early warning algorithm for Bursa province and its surroundings, which is a seismically active region. We replayed 104 earthquakes of M ≥ 3.5, which occurred in and around the study area between 2012 and 2021. We derived period and amplitude-based magnitude-scaling relationships using peak displacement amplitude (Pd) and predominant period (Tpmax) parameters of the first 4 s of P-wave arrivals. We investigated the performance of magnitude-scaling relationships through testing with real-time data. We observed an improvement when comparing the magnitude estimates made with the newly developed equations with the default equations used for California. We have also found that magnitude estimation with Pd gives better results than Tpmax for estimating the accurate final magnitude. We aim to adapt the EPIC early warning system, implemented for Bursa province and its surroundings, specifically for each region of Türkiye where the earthquake risk is high.

Depremleri izlemede kullanılan hız algılayıcılarının dinamik aralıkları (en büyük genliğin en düşük genliğe oranı) 165 dB civarında olmasına rağmen, bazen deprem dalgalarının meydana getirdiği yer hareketi hızı güçlü olduklarında, bu cihazların verisi doyuma giderek kırpılacağından, bu veriler kullanılamaz hale gelirler. Depremleri izleyen en önemli kurulumların başında Boğaziçi Üniversitesi Kandilli Rasathanesi ve Deprem Araştırma Enstitüsü (KRDAE) ve Afet ve Acil Durum Yönetimi Başkanlığı (AFAD) gelmektedir. Bu kurumlar; genişband sismik algılayıcı kullanmaktadır. Van ilinde, 23.10.2011 tarihindeki depremden sonra bu kurumlardaki sismik algılayıcıların kaydettiği sinyallerinin çoğunun doyuma ulaşması sonucu, sinyalin üstten ve/veya alttan kırpılmasıyla depremin büyüklüğü ve yerinin belirlenmesi konusunda sıkıntılar yaşanmıştır. Ülkemizde, yanlış bir şekilde yerleşmiş olan genişband sismik algılayıcılar doyuma ulaşmazlar inanışını değiştirmek amacı ile bu makalede genişband sismik algılayıcıların nasıl doyuma ulaştıkları hakkında bilgi verilecektir.