## 1 Introduction  
Denizli, a key city in Turkey's textile and traverntine industries, is one of the most significant urban centers in both Turkey and the Aegean Region, with a population exceeding one million. The Aegean region, encompassing the graben system, constitutes one of Turkey's most significant seismic zones. The faults within the Aegean graben generate numerous earthquakes, leading to various human and economic losses. Historical records document several major instrumental earthquakes in the region, including the 1899 Menderes earthquakes (M = 6.5 and 7.1), the 1956 Soke-Balat earthquake (M = 6.8), the 1965 Denizli earthquake (M = 5.7), the 1969 Alasehir earthquake (M = 6.7), and the 1970 Gediz earthquake (M = 7.2). The Acgol basin forms the approximate eastern boundary of the Aegean graben system in southwestern Anatolia. This region is characterized by rapid deformation and seismic activity due to dominant graben structures, including numerous small grabens in various orientations and larger east-west trending grabens. During the Late Oligocene to Early Miocene, the region experienced significant continental extension. This extension led to the formation of prominent morphological structures, such as the Gediz-Alasehir graben (GAG) and the Buyuk Menderes graben (BMG) (Figure 1). These structures have been extensively studied by researchers [1; 2; 3; 4; 5]. The east-west trending graben border faults are seismically active [6; 7; 8; 9; 10; 11; 12]. The formation of east-west trending grabens remains a subject of debate among researchers. Some argue that these grabens began to form during the Tortonian (Upper Miocene) [19], while others suggest that they originated in the Early Miocene and have continued to evolve up to the present [20,21]. Recent studies, however, indicate that Miocene sediments are not associated with the present-day grabens and propose that the development of east-west grabens occurred 5 million years ago (Plio-Quaternary) due to north-south extension [22]. In the eastern Aegean, NE-SW directional opening and, accordingly, NW-SE directional grabens/graben edge faults are active. These include the eastern part of the GAG, the Denizli graben (DG), the Dinar fault, and the Acipayam-Serinhisar fault [16]. The fault systems that form NW-SE trending grabens or grabens bounding faults are also active among others [23,24], as evidenced by the 1965 Denizli earthquake (M = 5.7) and the 1995 Dinar earthquake (M = 5.7). In western Anatolia, NE-SW trending basins and the elevations between them are secondary prominent tectonic features (e.g., Gediz, Simav, Gordes, Demirci, Selendi, and Usak-Gure basins). Particularly towards the east, NE-SW trending basins become more pronounced, including the Civril-Baklan graben (CBG), the Acigol graben (AG), and the Burdur graben (BG). Active faults forming grabens in this trend were highlighted by the 1914 Burdur earthquake (M = 7.0) and the 1971 Burdur earthquake (M = 5.9). Among these, the CBG in the NW and the BG in the SE predominantly trend NE-SW. The AG lies between them, trending NE-SW to the east and transitioning to an E-W trend towards the west. The  
Figure 1: (**A**) Location map in the tectonic framework of Turkey, annotations: NAF: North Anatolian Fault, EAF: East Anatolian Fault, NEAF: Northeast Anatolian Fault, BZTFB: Bitlis-Zagros Thrust and Fold Belt (modified from [13, 14, 15, 16]), (**B**) morphotectonic map of historical seismic faults and focal mechanisms in southwestern Anatolia [17] (via Google Maps). Annotations: BMG: Buyuk Menderes graben, KMG: Küçak Menderes graben, GAG: Gediz-Alasehir graben, DG: Denizli graben, CBG: Civril-Baklan graben, AG: Acigol graben, BG: Burdur graben, ASF: Acpayam-Serinhisar Fault, AF: Acpayam Fault, BF: Burdur Fault, AyF: Altnyayla Fault, KF: Kelekci Fault, CF: Cameli Fault (adapted from [5,16,18]). 2019 Bozkurt earthquake (M = 6.0) occurred along the western E-W trending fault of the Acgol depression, as inferred from fault-plane solution mechanisms [25] (Figure 2).