Endorsing Trusheim’s classic model of salt-diapir growth by the interpretation and restoration of seismic lines in the southern region of the Great-Tunb Island, Persian Gulf

Document Type : Research Paper

Authors

1 Department of Earth Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan, Iran

2 Geosciences Barcelona, Geo3Bcn-CSIC, Lluís Solé i Sabarís s/n, 08028 Barcelona, Spain

3 Department of Geophysics, Iranian Offshore Oil Company (Falat-Ghare), Tehran, Iran

Abstract

This paper investigates the geometry and evolution of the Oligocene and lower Miocene Fars salt diapirs and adjacent minibasins in the southeast Persian Gulf. Utilizing 2D offshore seismic lines, integrated with well data, we conducted detailed interpretations to construct NE-trending geological cross-sections south of the Great-Tunb Island. Subsequent stepwise restoration, guided by thickness patterns of syn-kinematic sediments, local unconformities, growth strata, and halokinetic sequences, unveiled the growth history of salt massifs, turtle anticlines, and salt horns featuring normal fault systems at their crests. Our findings reveal a synchronous evolution of Fars salt diapirs and nearby minibasins, aligning significantly with the classic Trusheim concept (1960). The identified stages encompass; 1) The pre-kinematic stage, coinciding with the deposition of the Gachsaran Formation in the Lower and Middle Miocene; 2) the Growth of salt pillows, concurrent with the basal deposition of the Guri Member at the Middle and Late Miocene boundary; 3) Passive and rapid diapir growth, synchronous with the Guri Member deposition in the Late Miocene; and 4) The post-diapirism stage and basins associated with salt incompressibility, corresponding to the deposition of the Upper Mishan and Aghajari formations during the Late Miocene and Pliocene times.

Keywords: Salt diapirism, Marine seismic data, Kinematic evolution, Minibasin, Fars Salt, Hormuz Salt

Keywords

Main Subjects


Article Title [Persian]

-

Ala, M. A., 1974. Salt diapirism in southern Iran. AAPG Bulletin, 58: 1758-1770.
Alavi, M., 2004. Regional stratigraphy of the Zagros fold-thrust belt of Iran and its proforeland evolution. American Journal of Science, 304: 1-20.
Callot, J. P., Trocmé, V., Letouzey, J., Albouy, E., Jahani, S., Sherkati, S., 2012. Pre-existing salt structures and the folding of the Zagros Mountains. Geological Society, London, Special Publications, 363: 545-561.
Ezati Asl, M. E., Faghih, A., Mukherjee, S., Soleimany, B., 2019. Style and timing of salt movement in the Persian Gulf basin, offshore Iran: Insights from halokinetic sequences adjacent to the Tonb-e-Bozorg salt diapir. Journal of Structural Geology, 122: 116-132.
Faghih, A., Ezati-Asl, M., Mukherjee, S., Soleimany, B., 2019. Characterizing halokinesis and timing of salt movement in the Abu Musa salt diapir, Persian Gulf, offshore Iran. Marine and Petroleum Geology, 105: 338-352. Fossen, H., 2016. Structural geology. Cambridge University Press.
Ghazban, F., Al-Aasm, I. S., 2007. Hydrocarbon-induced dolomite formation associated with Hormuz salt plug in the Persian Gulf, Iran. In GAC-MAC Annual Meeting. Yellowknife, Abstracts, 32: 31.
Groshong, R. H., Groshong, R. H., 1999. Elements of Map-Scale Structure. 3-D Structural Geology: A Practical Guide to Surface and Subsurface Map Interpretation, 1-32.
Hassanpour, J., Muñoz, J. A., Yassaghi, A., Ferrer, O., Jahani, S., Santolaria, P., SeyedAli, S. M., 2021. Impact of salt layers interaction on the salt flow kinematics and diapirism in the Eastern Persian Gulf, Iran: Constraints from seismic interpretation, sequential restoration, and physical modeling. Tectonophysics, 811: 228887.
Hassanpour, J., Yassaghi, A., Muñoz, J. A., Jahani, S., 2021. Salt tectonics in a double salt‐source layer setting (Eastern Persian Gulf, Iran): Insights from the interpretation of seismic profiles and sequential cross‐section restoration. Basin Research, 33: 159-185.
Jackson, M. P., Hudec, M. R., 2017. Salt tectonics: Principles and practice. Cambridge University Press.
Jahani, S., Callot, J.-P., Frizon de Lamotte, D., Letouzey, J., Leturmy, P., 2007. The salt diapirs of the eastern Fars province (Zagros, Iran): A brief outline of their past and present. In: Lacombe, O., Lav`e,
J., Roure, F., Verg`es, J. (Eds.), Thrust Belts and Foreland Basins. Springer, Berlin, 289–308.
Jahani, S., Callot, J.-P., Letouzey, J., Frizon de Lamotte, D., 2009. The eastern termination of the Zagros Fold-and-Thrust Belt, Iran: Structures, evolution, and relationships between salt plugs, folding, and faulting. Tectonics 28: TC6004.
Kent, P. E., 1979. The emergent Hormuz salt plugs of southern Iran. Journal of petroleum geology, 2:117-144.
Motiei, H., 1993. Stratigraphy of Zagros. Treatise on the Geology of Iran, 1: 60-151.
Najafi, M., Lajmorak, S., 2020. Contractional salt-tectonic system in the south Dezful embayment, Zagros. Journal of Structural Geology, 141: 104204.
Najafi, M., Beamud, E., Ruh, J., Mouthereau, F., Tahmasbi, A., Bernaola, G., Yassaghi, A., Motamedi, H., Sherkati, S., Goodarzi, M.G.H., Vergés, J., 2021. Pliocene growth of the Dowlatabad syncline in Frontal Fars arc: Folding propagation across the Zagros Fold Belt, Iran. Bulletin, 133: 1381-1403.
Peel, F. J., 2014. How do salt withdrawal minibasins form? Insights from forward modeling, and implications for hydrocarbon migration. Tectonophysics, 630: 222-235.
Pirouz, M., Simpson, G., Chiaradia, M., 2015. Constraint on foreland basin migration in the Zagros Mountain belt using Sr isotope stratigraphy. Basin Research, 27: 714-728. 306 Haji Khani et al.
Snidero, M., Carrera, N., Mencos, J., Butillé, M., Granado, P., Tavani, S., Muñoz, J. A., 2020. Diapir kinematics in a multi-layer salt system from the eastern Persian Gulf. Marine and Petroleum Geology, 117: 104402.
Stewart, S. A., 2018. Hormuz salt distribution and influence on structural style in NE Saudi Arabia. Petroleum Geoscience, 24: 143-158.
Trusheim, F., 1957. Über Halokinese und ihre Bedeutung für die strukturelle Entwicklung Norddeutschlands. Zeitschrift der deutschen geologischen Gesellschaft, 111-158.
Trusheim, F., 1960. Mechanism of salt migration in northern Germany. AAPG Bulletin, 44: 1519-1540.
Vendeville, B. C., 2002. A new interpretation of Trusheim's classic model of salt-diapir growth.