Seismic data, geometry, evolution, and shortening in the active Sulaiman fold-and-thrust belt of Pakistan, southwest of the Himalayas

Journal Article · Sun May 01 04:00:00 EDT 1994 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:7198653

Jadoon, I A.K. ^[1]; Lawrence, R D; Lillie, R J ^[2]

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1. Quaid-i-Azam Univ., Islamabad (Panama)
2. Oregon State Univ., Corvallis, OR (United States)

Despite its long history of exploration, the Sulaiman fold and thrust belt is a poorly known structure and detailed structural and geochemical investigations are vital for the successful exploration, evaluation and exploitation of any hydrocarbons. Recent nappe and duplex structural models provide a framework for exploration. Surface and subsurface data from the Sulaiman fold-and-thrust belt are integrated to analyze the deep structure, tectonic, shortening, and kinematics of the Sulaiman fold-and-thrust belt at the western margin of the Indian subcontinent. Seismic reflection data show that nearly all the 10-km-thick sequence of dominantly platform (>7 km) and molasse strata is detached at the deformation front. The strata thicken tectonically to about 20 km in the hinterland without significant thrust faults in the foreland. A balanced structural cross-section suggests that structural uplift in the Sulaiman fold-and-thrust belt is a result of a thin-skinned, passive-roof duplex style of deformation. Sequential restoration of the balanced section reveals a series of structural and geometrical features including: (1) development of low-amplitude, broad concentric folds at the tip of the decollement; (2) increase in amplitude of a detachment fold to a critical level for development of ramp and duplex structures; and (3) out-of-sequence thrusting to create required critical taper for an outward translation of the foreland fold-and-thrust belt. A balanced structural cross-section 349 km long from the Sulaiman fold-and-thrust belt restores to an original length of 727 km, suggesting a maximum of 378 km of shortening since 21 Ma in the cover strata of the Indian subcontinent. Calculation of displacement rates over the Sulaiman fold-and-thrust belt (18 mm/yr) added to the resolved rate of the Chaman fault vector for the component parallel to the plate convergence direction (15 mm/yr) are close to the current India-Asia plate convergence rate (37 mm/yr). 68 refs., 13 figs.

• OSTI ID: 7198653
• Journal Information: AAPG Bulletin (American Association of Petroleum Geologists); (United States), Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (United States) Vol. 78:5; ISSN 0149-1423; ISSN AABUD2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
ASIA
DEFORMATION
DEVELOPING COUNTRIES
DISPLACEMENT RATES
EXPLORATION
GEOLOGIC AGES
GEOLOGIC FAULTS
GEOLOGIC FRACTURES
GEOLOGIC HISTORY
GEOLOGIC MODELS
GEOLOGIC STRATA
GEOLOGIC STRUCTURES
GROUND UPLIFT
HYDROCARBONS
JURASSIC PERIOD
MAPPING
MESOZOIC ERA
ORGANIC COMPOUNDS
PAKISTAN
ROCKS
SEDIMENTARY ROCKS
SHALES