Identifying and evaluating thin-bedded reservoirs using well logging data: A case study in Well X, Field YT, Cuu Long Basin, Vietnam

Truong, Thanh Quoc; Nguyen, Kha Xuan; Nguyen, An Viet; Nguyen, Tuan; Xuan, Tran Van; Nguyen, Tin Trung; Dang, An Truong; Mai, Xuan Huu; Nguyen, Thong Huynh

doi:10.22059/jchpe.2026.379012.1536

Identifying and evaluating thin-bedded reservoirs using well logging data: A case study in Well X, Field YT, Cuu Long Basin, Vietnam

Document Type : Research Paper

Authors

Thanh Quoc Truong ¹^{, 2}

Kha Xuan Nguyen ¹^{, 2}

An Viet Nguyen ¹^{, 2}

Tuan Nguyen ³^{, 2}

Tran Van Xuan ⁴^{, 2}

Tin Trung Nguyen ¹^{, 2}

An Truong Dang ⁵^{, 2}

Xuan Huu Mai ⁶^{, 2}

Thong Huynh Nguyen ¹^{, 2}

¹ Faculty of Geology & Petroleum Engineering, Ho Chi Minh City University of Technology, Ho Chi Minh City, Vietnam.

² Vietnam National University Ho Chi Minh City, Ho Chi Mihn City, Vietnam.

³ Faculty of Geology, Ho Chi Minh City University of Science, Ho Chi Mihn City, Vietnam.

⁴ Faculty of Geology & Petroleum Engineering, Ho Chi Minh City University of Technology, Ho Chi Minh City, Vietnam

⁵ Faculty of Physics, Ho Chi Minh City University of Science, Ho Chi Mihn City, Vietnam.

⁶ Faculty of Applied Science, Ho Chi Minh City University of Technology, Ho Chi Mihn City, Vietnam.

10.22059/jchpe.2026.379012.1536

Abstract

During the current period of decline in oil and gas production in the Cuu Long Basin, it is necessary to evaluate a typical reservoir. One of the important geometrical reservoirs is the thin-bed reservoir. To determine the presence and evaluate the potential of thin-bedded reservoirs, well logging data are normally used. At Well X in the Cuu Long basin, the distribution of Gamma Ray values (histogram), log curves from well logging techniques, and geological analysis are used to calculate the percentages of sand and shale. Based on these results, thin-bedded reservoirs will be recognized. In this study, the sand percentage ranges from 40% to 60% (equivalent to a shale percentage range of 60% to 40%), indicating the presence of thin-bed layers. Porosity and permeability tend to decrease with increasing depth, particularly when moving from the Lower Miocene formation to the Upper Oligocene formation.

Keywords

Cuu Long Basin

Reservoir

Thin-Bedded Reservoir

Well Logging

Subjects

Hydrogen generation and fuel cell

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