Validating Structural Styles in the Flysch Basin Northern Rif (Morocco) by Means of Thermal Modeling

Abstract

Vitrinite reflectance and a micro-Raman spectroscopy parameters data set have been acquired on dispersed organic matter of the Maghrebian flysch basin and the Tangiers unit across a NE-SW section in the north-western Rif belt (North Morocco). Thermal maturity shows increasing values from the hinterland to the external unit (from NE to SW). Paleo-thermal indicators show that the internal flysch basin (i.e., the Mauretanian unit) is less mature than the external one, (i.e., the Massylian unit), with Ro% and Ro eq. Raman values ranging from 0.64% to 1.02% (from early mature to late mature stages of hydrocarbon generation). 1D thermal modeling estimates the overburden now totally eroded ranging from 3.1 km to 6.0 km, and has been used as constraint to reconstruct the complete thrust wedge geometry in Miocene times. The reconstructed geometry accounts for high shortening (about 63%) due to the development of an antiformal stack in the frontal part of the wedge made up by the flysch succession. This stacking is interpreted as a consequence of the western translation of the Alboran Domain in the core of the Betic-Rif orogenic system.

An insight on the polyphase thermal history of the Internal Rif (Northern Morocco) through Raman micro-spectroscopy investigation

“…The Rif belt is classically divided into three main tectono-stratigraphic domains (Favre & Stampfli, 1992;Frizon De Lamotte et al, 2011), namely from north to south and from internal to external portion of the chain: (i) Internal or Alboran Domain (Milliard, 1959;Bouillin, 1986;García-Dueñas et al, 1992), (ii) Maghrebian Flysch Basin Domain (Guerrera Et al., 1993Lepretre Et al., 2018;Atouabat Et al., 2020), and (iii) External Domain (Didon et al, 1973;Leblanc, 1979;Michard et al, 2014;Gimeno-Vives et al, 2019;Gimeno-Vives et al, 2020). The internal domain, object of this work, is subdivided into three tectonic complexes, recognized from bottom to top as: Sebtides complex, Ghomarides complex and the 'Dorsale Calcaire' (EL KADIRI et al, 1992).…”

Validating far-field deformation styles from the Adjara-Trialeti fold-and-thrust belt to the Greater Caucasus (Georgia) through multi-proxy thermal maturity datasets

“…Less frequently, it is applied to validate structural styles in deformed orogenic belts (e.g. Aldega et al, 2018;Atouabat et al, 2020;Balestra et al, 2019;Caricchi et al, 2015;Di Paolo et al, 2014;Muirhead et al, 2020;Tozer et al, 2020), either because of lack of constraints on timing of exhumation that can bias thermal modelling, or because such indicators mostly derive from surface outcrops and can allow modelling only of pseudo-well sections, rather than present-day boreholes, introducing an extra degree of uncertainty.…”

A Predictive Model for Maceral Discrimination by Means of Raman Spectra on Dispersed Organic Matter: A Case Study from the Carpathian Fold-and-Thrust Belt (Ukraine)

“…In thermal model calibration for petroleum exploration and basin analysis, vitrinite reflectance is still the most accurate and reliable indicator [2][3][4][5]. On the other hand, vitrinite discrimination among different organic facies has always been a critical issue for a correct assessment of thermal maturity [6,7], in particular when other low reflecting macerals occur [8][9][10][11]. Given this and the occurrence of other pitfalls that can interfere with vitrinite reflectance assessment (e.g., suppression and retardation [12,13] and references therein), alternative methods have been proposed, such as palynomorph darkness index (PDI, [14,15]), FT-IR spectroscopy [16][17][18][19][20], NMR [21], XPS [22], or Raman spectroscopy [23][24][25][26][27][28][29][30][31][32][33].…”