نشریه زمین شناسی محیط زیست
پیاپی 65 (زمستان 1402)

The southwestern region of Lorestan, Zagros in Iran is known for its seismic activity, which is a result of the Arabian and Eurasian plates converging. This region is a part of the Alpine–Himalayan orogenic system, which was formed due to the closure of the Neo-Tethys oceanic during the Cenozoic era.

This study aims to explore the environmental impact of earthquakes in this region, with a special focus on the effects on geological features such as hidden faults, numerous fractures, a sedimentary layer, the Gachsaran Formation, and Hormuz salt.

The study involved the analysis of seismic waveforms collected from 2006 to 2019 from a network of 36 seismic stations. The quality factor of seismic body waves was estimated using the extended coda normalization method. Additionally, a quantitative morphometric evaluation was conducted through the Tu index to predict the catchment-scale suspended sediment yield on the scar area and derive the erosion rate affecting the landslide after the cut of the landslide dam by the Seymareh River.

The study found that the attenuation of seismic waves in the Zagros area is significant due to geological features such as hidden faults, numerous fractures, a sedimentary layer, the Gachsaran Formation, and Hormuz salt. The spatial variation in Q values reveals that the attenuation is higher in the northern parts of the region than in the southern parts. The Seymareh Landslide, one of the largest rock mass movements on the Earth’s surface with an estimated volume of 44 Gm 3, is a significant geological event in this region.

The study concludes that earthquakes in the southwestern region of Lorestan, Zagros have a significant environmental impact, particularly on geological features. The significant attenuation of seismic waves in the area is due to the complex geological features, leading to gravity-induced phenomena with considerable implications for natural hazards. The Seymareh Landslide serves as a prime example of the large-scale geological changes that can occur as a result of seismic activity.

The horse breeding and keeping industry has created employment in many provinces of the country. The purpose of this research is to investigate the potential of using organic waste from riding and horse breeding complexes. The waste of equestrian and horse breeding complexes is mainly organic and includes manure and bedding. This research was done in the spring and summer of 2023. To obtain information, an online questionnaire was provided to people who were somehow related to riding and horse breeding centers. The results of the questionnaire were analyzed and analyzed by SPSS software and statistical tests. The waste of one of the equestrian clubs was performed and physical, chemical and biological tests were performed. The physical analysis of the fertilizer of the physical waste (fertilizer and substrate) shows the values of ash 23.6%, 66% moisture and 34% dry matter. The measurement of the C/N ratio showed that horse fertilizer has high values of C/N. The amount of phosphorus 192 ppm, nitrogen 5.63%, organic carbon 44.3%, C/N ratio 7.8, ammonia 125.2 ppm, organic matter 76.4%, zinc 62.50 ppm, iron 65 ppm and copper 11.80 ppm have been seen in horse litter. Ash 23.6%, moisture 66% and dry matter (solid) 34% were measured. horse fertilizer is not dangerous to humans in terms of coliforms and pathogens. The calorific value of horse manure showed that this waste can also be used as fuel.

Based on the research results and tectonic indicators, the region is in an average tectonic state. One of the threatening factors in the region is the effect of the Minab fault on the rise of the region, which increases the slope of the region in the northern parts. This, in turn, causes an increase in water flow and flooding of rivers in the downstream areas and causes slope instability and landslides in the region. The purpose of this research is to provide valuable insights about the influence of the geological structures of the region on the future geological and environmental challenges. By calculating morphotectonic parameters and morphometric indices in order to estimate the tectonic risks of Minab fault, its role on geological-environmental risks has been discussed. Based on this, the effect of the Minab fault on the rise of the region can increase the slope of the region in the northern parts and lead to an increase in water flow and river flooding in the downstream areas. This can cause slope instability and landslides in the region. In terms of tectonic risks, the existence of the Minab fault and its related tectonic activity can lead to various tectonic risks, including earthquakes. As a result, while the Minab fault and related tectonic activities can create significant environmental challenges, with proper planning and understanding of tectonic conditions, these challenges can be reduced and lead to sustainable development. The area helped.