Hydrocarbon accumulation in basins with multiple phases of extension and inversion: examples from the Western Desert (Egypt) and the western Black Sea

Abstract

Abstract. Folds associated with inverted extensional faults are important exploration targets in many basins across our planet. A common cause for failure to trap hydrocarbons in inversion structures is crestal breaching or erosion of top seal. The likelihood of failure increases as the intensity of inversion grows. Inversion also decreases the amount of overburden, which can adversely affect maturation of source rocks within the underlying syn-extensional stratigraphic section. However, many rift basins are multi-phase in origin, and in some cases the various syn-rift and post-rift events are separated by multiple phases of shortening. When an inversion event is followed by a later phase of extension and subsidence, new top seals can be deposited and hydrocarbon maturation enhanced or reinitiated. These more complex rift histories can result in intra-basinal folds that have higher chances of success than single-phase inversion-related targets. In other basins, repeated inversion events can occur without significant intervening extension. This can also produce more complicated hydrocarbon maturation histories and trap geometries. Multiple phases of rifting and inversion affected numerous basins in North Africa and the Black Sea region and produced some structures that are now prolific hydrocarbon producing fields and others that failed. Understanding a basin's sequence of extensional and contractional events and the resulting complex interactions is essential to formulating successful exploration strategies in these settings.

Together but separate: decoupled Variscan (late Carboniferous) and Alpine (Late Cretaceous – Paleogene) inversion tectonics in NW Poland

“…As it was described and illustrated above, the area analysed in this paper underwent two phases of inversion. Repeated extension and compression realized along the same faults have been described by many authors (e.g., Bosworth and Tari, 2021;Dichiarante et al, 2020;Minguely et al, 2010). In our case, the presence of Zechstein evaporites resulted in mechanical decoupling between the Devonian-Carboniferous and Triassic-Cretaceous levels, and, despite close location, both inversion structures evolved independently.…”

Analogue modelling of the inversion of multiple extensional basins in foreland fold-and-thrust belts

“…It has been recognised that rifts with highly faulted crust are prone to early inversion in collision-related intraplate deformation (e.g. Ziegler 1995;Angrand et al, 2021), but in how far horizontal stresses can act and reactivate pre-existing extensional structures, and to what extent, is still elusive 45 (Bosworth and Tari, 2021).…”

Analogue modelling of basin inversion: a review and future perspectives

“…Inverted basins are very common geological features and are found in multiple locations, for instance the North Sea area (Lamplugh, 1919;Glennie and Boegner, 1981;Nalpas et al, 1995;Evans et al, 2003;De Jager, 2003;Hansen et al, 2021), the Pyrenees and European Alps (Pfiffner, 1993;Ziegler et al, 1995;Kiss et al, 2020;Mencos et al, 2015;Lescoutre and Manatschal, 2020;Musso Piantelli et al, 2022), the Atlas Mountains (Vially et al, 1994), Iran (Boutoux et al, 2021), the Araripe Basin in northeastern Brazil (Marques et al, 2014), the Andes (Ferrer et al, 2022b, and references therein), offshore of Korea (Park et al, 2021), and China (Yu et al, 2021), as well as many other places around the globe (Letouzey, 1990;Lowell, 1995;Iaffa et al, 2011;Gibson and Edwards, 2020;Bosworth and Tari, 2021;Dooley and Hudec, 2020).…”