High-Resolution Sequence Stratigraphy of Upper Shuaiba Member Aptian 5, Lower Cretaceous, In the Southeast of United Arab Emirates

The Upper Shuaiba Member (USM) or Apt 5 (Whitecomb et al. 2021; Alsuwaidi et al. 2022) has proven significantly prolific hydrocarbon potential, as evidenced by numerous oil fields (e.g., Safah, Malaan, Deleel Fields), particularly along the eastern margin of the Bab Basin (Al Habsi et al. 2014), in relation to the currently recognized position of the intrashelf basin (Murris 1980; Sharland et al. 2001; van Buchem et al. 2002; Yose et al. 2010; Yamamoto et al. 2013). In order to understand the depositional environments and the internal architecture of the Aptian sediments, numerous wells have been drilled since the 1980s (Boote and Mou 2003), resulting in the depositional models (e.g., Safah Field) exhibiting thin, low-angle prograding clinoforms, extending over 100 km from the northwest of Oman through the United Arab Emirates (UAE) to the southwest. The prograding clinothems consist of shallow, high-energy inner ramp settings to deeper, low-energy outer ramp zones (Boote and Mou 2003). Seismic characteristics of the USM in the east of the intrashelf basin, however, appear to be relatively poorly defined as compared to those in the west, largely due to low seismic resolution and quality. Therefore, considerable challenges have been posed to their seismic stratigraphic analysis. As a result, the detailed internal structures and associated facies distribution are not fully explored. To date, few interdisciplinary studies have been conducted to comprehensively delineate these aspects of the fourth-order sequences in the eastern margin of the intrashelf basin. The present study aims to elucidate the depositional evolution and assess the hydrocarbon reservoir potential of the USM by combining the drilled well data and two seismic cubes covering 4,400 km2. This approach seeks to detail the USM's characterization, thereby providing a more comprehensive framework for hydrocarbon exploration and development.