Role of preexisting faults in the geodynamic evolution of Northern Tunisia, insights from gravity data from the Medjerda valley

Amiri, Adnen; Chaqui, A.; Nasr, Imen Hamdi; Inoubli, Mohamed Hédi; Ayed, Naceur; Tlig, S.

doi:10.1016/j.tecto.2011.03.004

Cited by 41 publications

(16 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It depicts one of a series of long, E-W right-lateral strike-slip crustal fault system (Aoudia et al, 2000;Jallouli et al, 2013) that is characteristic for northern Africa and extends over 200 km from the high mountains of Debagh (in Algeria; Meghraoui, 1988;Vila, 1980) in the west to Thibar region (in northern Tunisia) in the east. This E-W major fault zone is reported clearly in previous geological studies (e.g., Bounif et al, 1987;Guiraud, 1977;Maouche et al, 2013;Meghraoui, 1988;Rouvier, 1977;Vila, 1980), geophysical data (e.g., Amiri et al, 2011;Harbi et al, 1999) as a dextral strike-slip fault system. Moreover, it is characterized by neotectonic and seismotectonic activities (Harbi et al, 1999)…”

Section: The Eastern Tell (Box 1)supporting

confidence: 74%

Active Faulting Geometry and Stress Pattern Near Complex Strike‐Slip Systems Along the Maghreb Region: Constraints on Active Convergence in the Western Mediterranean

et al. 2018

View full text Add to dashboard Cite

The Maghreb region (from Tunisia to Gibraltar) is a key area in the western Mediterranean to study the active tectonics and stress pattern across the Africa‐Eurasia convergent plate boundary. In the present study, we compile comprehensive data set of well‐constrained crustal stress indicators (from single focal mechanism solutions, formal inversion of focal mechanism solutions, and young geologic fault slip data) based on our and published data analyses. Stress inversion of focal mechanisms reveals a first‐order transpression‐compatible stress field and a second‐order spatial variation of tectonic regime across the Maghreb region, with a relatively stable SHmax orientation from east to west. Therefore, the present‐day active contraction of the western Africa‐Eurasia plate boundary is accommodated by (1) E‐W strike‐slip faulting with reverse component along the Eastern Tell and Saharan‐Tunisian Atlas, (2) a predominantly NE trending thrust faulting with strike‐slip component in the Western Tell part, and (3) a conjugate strike‐slip faulting regime with normal component in the Alboran/Rif domain. This spatial variation of the present‐day stress field and faulting regime is relatively in agreement with the inferred stress information from neotectonic features. According to existing and newly proposed structural models, we highlight the role of main geometrically complex shear zones in the present‐day stress pattern of the Maghreb region. Then, different geometries of these major inherited strike‐slip faults and its related fractures (V‐shaped conjugate fractures, horsetail splays faults, and Riedel fractures) impose their component on the second‐ and third‐order stress regimes. Neotectonic and smoothed present‐day stress map (mean SHmax orientation) reveal that plate boundary forces acting on the Africa‐Eurasia collisional plates control the long wavelength of the stress field pattern in the Maghreb. The current tectonic deformations and the upper crustal stress field in the study area are governed by the interplay of the oblique plate convergence (i.e., Africa‐Eurasia), lithosphere‐mantle interaction, and preexisting tectonic weakness zones.

show abstract

Section: The Eastern Tell (Box 1)supporting

confidence: 74%

Active Faulting Geometry and Stress Pattern Near Complex Strike‐Slip Systems Along the Maghreb Region: Constraints on Active Convergence in the Western Mediterranean

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Owing to the successive compressive and extensive phases, the master strike slip displacements participate to the reactivation of the Triassic material. This geodynamic evolution is well illustrated in the diapir zone (Perthuisot 1978; Sarsar Naouali et al 2010; Amiri et al 2011), where the Triassic salt ascendance is facilitated by strike‐slip‐fault movements and causes the appearance of Triassic bodies such as pillows, diapir structures and salt glaciers.…”

Section: Discussionmentioning

confidence: 93%

Subsurface geology of the Ariana region (Diapir Zone, northern Tunisia) by means of gravity analysis

Naouali¹,

Inoubli²,

Amiri³

et al. 2011

Geophysical Prospecting

Self Cite

View full text Add to dashboard Cite

Gravity data were used to investigate subsurface geology in the Ariana region from the Diapir Zone in Tunisia. Our study area is located in the north‐eastern part of the Maghrebides affected by the Alpine orogeny. Despite the smooth topography and the low density of the Quaternary series, integrated geological data and gravity responses (Bouguer anomaly and derivative mapping) help decipher the geological heterogeneities beneath the Quaternary overburden. The interpretation of the gravity data points to alignments of positive anomalies delineating two major orthogonal features that are thought to characterize the subsurface deep structures: 1) a lineament striking north‐west at the emplacement of an actual horst bordered by a buried fault‐system directed N140 and 2) a second counterpart striking north‐east, and is clearly expressed in the surface outcrops. These principal structural features were described as the result of a regional tectonic, compressive phase dating the Miocene. This phase was marked by reactivation and oblique‐slip displacements of regional faults; some of which (N070) are reverse and south‐east vergent. Further faulting enhanced the ascension of Triassic evaporites in diapir structures. This tectonic evolution may be integrated in the regional tectonic scheme of Alpine orogeny induced by a collision between African and European plates.

show abstract

“…SO42. may also be de.rived from surface waterÐgroundwater interactions associated with the oxidation of pyrite derived from the Medjerda sand.stone (Amiri et al 2011). Ca2+ and Mg2+ concentrations were also generally high (Table 3) and reflect the major contribu.tion of calcite dissolution in the groundwater mineralization processes of the Medjerda Sandstone, and indicate a strong association with the lithology of the dolomines and dolomite limestones from the Jurassic and Middle Triassic periods.…”

Section: Discussionmentioning

confidence: 99%

Surface water quality assessment in a semiarid Mediterranean region (Medjerda, Northern Tunisia) using partial triadic analysis

Slimani

Jiménez

Guilbert³

et al. 2020

Environ Sci Pollut Res

View full text Add to dashboard Cite

A range of methods have been developed specifically to analyze several tables of data simultaneously (variable . space . time) in the field of ecological research, although they have been less widely used to examine water quality. In this study, we assessed the spatiotemporal variability of water quality in the Medjerda River basin (Northern Tunisia). Partial triadic analysis (PTA) provides an effective framework for the assessment of spatiotemporal variability of water quality in the Medjerda River basin (Northern Tunisia). Fourteen physicochemical variables were monitored from 12 sampling sites monthly during 2013. PTA allowed correlations among different physicochemical parameters to be identified and to assess overall water quality in the Medjerda River. Salinity (S), Cl.,SO42.,Ca2+,and Mg2+ ions were associated with intensive agricultural activities (agricultural pollution sources) leading to salinization. However, NH4+,PO43. , chemical oxygen demand (COD), and biochemical oxygen demand (BOD5) we more strongly associated with polluted urban sites. PTA helped illustrate that strong links exist between land uses and adjacent water quality. The advantages of this multi-table method approach for water quality monitoring include as follows: (1) identifying common multivariate spatial structures and problems associated with maintaining water quality, (2) allowing iden.tification of consistent patterns in water chemistry, and (3) allowing analysis on the temporal variability of water chemistry.

show abstract

Role of preexisting faults in the geodynamic evolution of Northern Tunisia, insights from gravity data from the Medjerda valley

Cited by 41 publications

References 17 publications

Active Faulting Geometry and Stress Pattern Near Complex Strike‐Slip Systems Along the Maghreb Region: Constraints on Active Convergence in the Western Mediterranean

Active Faulting Geometry and Stress Pattern Near Complex Strike‐Slip Systems Along the Maghreb Region: Constraints on Active Convergence in the Western Mediterranean

Subsurface geology of the Ariana region (Diapir Zone, northern Tunisia) by means of gravity analysis

Surface water quality assessment in a semiarid Mediterranean region (Medjerda, Northern Tunisia) using partial triadic analysis

Contact Info

Product

Resources

About