Scholarlink

<p>The Chorgali Formation (Early Eocene), exposed in the Hazara Basin near Khanpur Dam, District Haripur, was investigated to reconstruct its depositional environment and characterize its microfacies. Although Eocene carbonate successions in other basins of Pakistan have been studied, the depositional setting and microfacies variability of the Chorgali formation in the Hazara Basin remain poorly understood. This study addresses this gap by integrating field observations and petrographic analyses. The section is exposed along the Khanpur-Haripur Road, showing a maximum thickness of 96&#xa0;m. It primarily comprises massive, thick-bedded, medium to thin-bedded, and nodular limestone with shale intercalations. Five distinct microfacies were identified: as Foraminiferal Mudstone Microfacie (CMF1), Foraminiferal Wackestone (CMF2a), Foraminiferal Wacke–Packstone (CMF2b), Assilina-dominated Packstone Microfacies (CMF3), and Nummulites–Assilina packstone–grainstone (CMF4). The microfacies are dominated by larger benthic foraminifera, particularly <i>Nummulites</i> sp., and <i>Assilina</i> sp., whose distribution patterns provide key insights into the depositional setting. Microfacies analysis combined with field observations suggests that the Chorgali Formation was deposited in inner-to middle-ramp environments under predominantly low-to moderate-energy conditions. Moreover, the prevalence of shallow water benthic foraminifera further supports this interpretation, reflecting the depositional setting during the Early Eocene. Diagenetic processes result in both porosity enhancement and reduction, depending on the specific type of diagenetic modifications. The present study provides a comprehensive understanding of the microfacies and depositional environment, enhancing the current knowledge of carbonate sedimentation within the Hazara Basin.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Microfacies analysis and depositional environment of Eocene Chorgali formation at Khanpur Dam Road Section, Hazara Basin, Pakistan

  • 期刊论文

  • 发表日期：

    2025年11月6日

查看全文
  • Bilal Shah,
  • Syed Mamoon Siyar,
  • Salman Khurshid,
  • Dicky Muslim,
  • Raden Irvan Sophian,
  • Zahid Ullah,
  • Abdul Wahid Asykarulloh,
  • Asad Muhammad,
  • Syed Muhammad,
  • Wasim Sajjad

摘要

The Chorgali Formation (Early Eocene), exposed in the Hazara Basin near Khanpur Dam, District Haripur, was investigated to reconstruct its depositional environment and characterize its microfacies. Although Eocene carbonate successions in other basins of Pakistan have been studied, the depositional setting and microfacies variability of the Chorgali formation in the Hazara Basin remain poorly understood. This study addresses this gap by integrating field observations and petrographic analyses. The section is exposed along the Khanpur-Haripur Road, showing a maximum thickness of 96 m. It primarily comprises massive, thick-bedded, medium to thin-bedded, and nodular limestone with shale intercalations. Five distinct microfacies were identified: as Foraminiferal Mudstone Microfacie (CMF1), Foraminiferal Wackestone (CMF2a), Foraminiferal Wacke–Packstone (CMF2b), Assilina-dominated Packstone Microfacies (CMF3), and Nummulites–Assilina packstone–grainstone (CMF4). The microfacies are dominated by larger benthic foraminifera, particularly Nummulites sp., and Assilina sp., whose distribution patterns provide key insights into the depositional setting. Microfacies analysis combined with field observations suggests that the Chorgali Formation was deposited in inner-to middle-ramp environments under predominantly low-to moderate-energy conditions. Moreover, the prevalence of shallow water benthic foraminifera further supports this interpretation, reflecting the depositional setting during the Early Eocene. Diagenetic processes result in both porosity enhancement and reduction, depending on the specific type of diagenetic modifications. The present study provides a comprehensive understanding of the microfacies and depositional environment, enhancing the current knowledge of carbonate sedimentation within the Hazara Basin.