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This review article aims to provide details on the primary phytochemicals found in Acacia and its numerous pharmacological activities. For those working on the creation of new pharmaceutical products, this review is helpful.

Recognizing ancient deltas' depositional architecture is challenging due to the complex interplay of the fluvial, waves, and tidal processes. The integration of field-based sedimentological and trace fossils studies of the Late Cambrian-Early Ordovician Barik Formation in Central Oman allowed better identification of different lithofacies architectures and depositional process signatures. The Barik Formation is a major tight-gas reservoir in the Oman Sedimentary Basins, where it is over 800-m thick. The only outcrop analogue is in the Qarn Mahatta Humaid area, where ca. 50-m thickness of the formation is exposed and extends laterally over 5 km. This study revealed the presence of four lithofacies associations, including (a) mouth bar/shoreface, (b) tidal flat, (c) tidal channel, and (d) delta distributary channels using 12 logged sections. The depositional features identified in the field include tidal, wave/storm, and fluvial. The tidal signatures are represented by mud-drapes, large-scale reactivation surfaces, sigmoidal cross-bedding, and climbing and flaser bedding, predominantly in the mixed mud-sand tidal flats of the lower delta plain and delta distributary channels of the upper to lower delta plains. The wave/storm signatures are represented by wave ripples and small-scale hummocky cross-stratification in the mouth bar/shoreface of the delta front platform. The fluvial and subaerial signatures are represented by the occurrence of the scour surfaces with lag deposits of channel-fill and the development of desiccation mud-cracks. The Barik Formation delta sandstones form amalgamated sheet-like bodies prograding to the north-northeast and deposited along a ramp-type low relief basin. This prograding delta represents a highstand system tract. This study presents an example of the ancient fine-grained hybrid-energy prograding delta, where fluvial processes operated beside the tidal and wave/storm processes over a broad and low relief shelf in a vegetation-free system. This work is supported by His Majesty's Trust Fund Grant # SR/SCI/ETHS/15/01 to Sultan Qaboos University (SQU)

Kariz (Qanat or Roman Aqueduct) is an old knowledge that has been used in more than 35 countries. Kariz, previously recognized as a water management technology, involves horizontal subsurface galleries and vertical monitoring shafts, which works based on natural gravity force. This paper reviews various geoengineering and environmental impacts studies that have been carried out on Kariz networks during recent decades. Geoengineering studies aim to figure out the location, geometrical structure, depth and path of Kariz galleries, which characterize a major hazard particularly in sites located in cities. Among the geoengineering studies, geophysical methods such as electrical resistivity tomography (ERT), ground-penetrating radar (GPR) and electromagnetic (EM) methods are very common methods in exploring underground tunnels and other structural parameters related to Karizes. Defining the location and size of un-mapped Karizes also help to estimate the risk of subsidence and to develop plans for restoration and safety. Further, remote sensing and geographic information system (GIS) techniques, which have been recently applied in a number of fields, are discussed. These new techniques help to map the positioning of networks in regions. Other emerging impacts of Kariz systems as an environmentally-friendly technology, its impacts on tourism attraction, land subsidence, and water management have been explored here. Due to modern lifestyle and demand for clean water as a result of population growth, especially in semi-arid or arid climates, this review study aims to explore the important role of Kariz system as a sustainable way of underground water management.

This is the first comprehensive study of the >170-m-thick late Oligocene to Pliocene(?) Barzaman Formation from the northern side of the Oman Mountains. Our work closes a major gap in the understanding of a complex geological interval and region which was affected by regional doming, syndepositional thrusting, changing eustatic sea level and changing climate. The dynamic, and diverse setting is reflected by the formationʼs varied lithologies. Based on seven measured sections we subdivided the Barzaman Formation into five lithostratigraphic units which we correlated over a distance of 1.3 km. The lower three units are shallow marine, the remaining two units are terrestrial. The marine development was at first siliciclastic (near-shore; Unit 1), followed by coral limestone deposition with some associated siliciclastics (Unit 2) and then siliciclastic again (Unit 3). The limestones include a coral-bearing limestone debrite. Associated (or at least contemporary) with the debris flow, are coral limestone boulders which rolled downslope beyond the area of limestone deposition. The lower terrestrial unit (Unit 4) is marked by isolated lenticular claystone beds within weathered conglomerates. The claystone beds, which may be cellular, consist of palygorskite and commonly also of saponite. Their clay mineralogy, limited areal extend and association with conglomerates indicate their origin from evaporation of small ponds/pools between wadi gravel. Within the claystones and conglomerates, two slides were identified. These slides and the limestone debrite indicate slope instability which we attribute to syndepositional thrusting. Thrust deformation may explain the thickness variations of units 2–4. The uppermost Unit 5 is characterized by highly altered conglomerates whose primary features are largely obliterated by diagenesis such as (1) alteration and replacement of igneous ophiolite clasts, (2) local basal silica cementation and (3) mainly dolomite cement with some calcite cement. Based on the general geological setting (doming, falling eustatic sea level) and the involved near-surface diagenetic processes we interpret these conglomerates as terrestrial. Diagenesis of Unit 5 indicates an increasingly wet climate. Considering the foraminifer-constrained age of Unit 2, paleostress constraints and dated climatic change data, we conclude that the Barzaman Formation dates as late Oligocene to at least the mid-Miocene.

We logged five outcrops of the Middle Limestone Member (MLM) of the Early Eocene Rusayl Formation. The eastern sections contain more, much coarser and also more angular detritus than the western sections. Moreover, notable concentrations of red algae , gastropods , corals, oysters and echinoids only occur in the eastern sections. Benthic foraminifers are typical for the entire MLM, but in the west, they are more abundant (dominated by miliolids). Peloids are restricted to the western sections. While the western sections display a subtidal lagoonal facies , capped by thin intertidal deposits, the coarse clastic material of the eastern sections indicates the proximity of a mountainous paleocoast with a resulting rocky coast environment. The coarse eastern facies proves that the Saih Hatat Dome as part of the Oman Mountains had already emerged while the MLM accumulated. Because of the differences, no outcrop correlations between the western and eastern sections are possible. However, facies boundary correlations among the western sections are feasible, spanning a distance of 23.5 km. Among the eastern sections, basal coarse clastics as well as two bioclastic marker horizons were correlated over 26 km. Deposition of the MLM was favored by high temperatures during the Early Eocene Climatic Optimum (EECO) at 53-51 Ma and a correspondingly high eustatic sea-level. The presence of corals in proximity of a mountainous, rocky paleocoast indicates dry conditions (clear water) during the EECO. The final shallowing-up observed in the west is attributed to the end of the EECO when mean global temperatures and the eustatic sea-level dropped. Shallowing from subtidal to intertidal conditions restricted parts of the lagoon and caused evaporation/hypersaline conditions as indicated by monospecific small miliolids and also by early dolomitization due to Mg-rich brines (reflux model). The western sections show signs of dolomitization. The Al-Khod section is the first one to be reported to be intensely dolomitized.

Two new species of larger benthic foraminifera, Neorotalia omanensis n. sp. and Operculina musawaensis n. sp. are described and illustrated from the eastern Oman Mountains. N. omanensis n. sp. occurs in the Musawa Formation in association with the planktonic foraminifera Morozovella edgari and Truncarotaloides topilensis indicating an early to middle Eocene age (P10-P13). Operculina musawaensis n. sp. occurs in the Abat Formation in association with the planktonic foraminifera Acarinina esnaensis and A . soldadensis indicating an early Eocene age (P6). This is the first known record showing the presence of genus Neorotalia in the Middle East. Representatives of the larger foraminiferal genus Linderina sp. are also described and illustrated from the Musawa Formation and compared with the published Linderina species in the surrounding countries .

Four species, Arxina parva (Douville, 1930), Arxina cf. schwageri (Silvestri, 1928) A. schwageri (Silvestri, 1928) and Arxina sp. cf. alpina (Douville, 1916) assigned to the newly erected genus Arx...

An early Oligocene (Rupelian) diagnostic larger foraminiferal assemblage is described and illustrated from marls and limestones of the Asmari Formation, at Jabals Hafit and Malaqet in the UAE. An equivalent assemblage is identified in the mudstones of the Tahwah Formation, Wadi Suq, Oman. Although Nummulites intermedius (D'Archiac 1846) and N. fichteli are fully synonymous (e.g. Roveda 1970; Schaub 1981; Sirel 2003), in this study both species are biometrically differentiated, distinct and both names are valid. N. fichteli Michelotti 1841, N. intermedius (D'Archiac 1846) and N. emiratus n. sp., which are index for the early Oligocene (Rupelian), and they are replacing each others competitively and environmentally. The presence of Blondeauina bouillei n.gen., N. emiratus n.sp., N. intermedius, N. fichteli, Planoperculina complanata (Defrance 1822) and Austrotrillina asmariensis Adams 1968 ascribed the section of the Asmari Formation to the early Oligocene (Rupelian). The studied marls and limestones were d...

Allochthonous carbonatite and ultramafic lamprophyre occur in a diatreme at the beach of the Asseelah village, northeastern Oman. The diatreme consists of heterogeneous deposits dominated by ‘diatreme facies’ pyroclastic rocks. These include aillikite and carbonatite, which intrude late Jurassic to early Cretaceous cherts and shales of the Wahra Formation within the Batain nappes. Both rock types are dominated by carbonate, altered olivine, Ti–Al–phlogopite and Cr–Al–spinel and contain varying amounts of apatite and rutile. The carbonatite occur as fine-grained heterolithic breccias with abundant rounded carbonatite xenoliths, glimmerite and crustal xenoliths. The aillikite consists of pelletal lapilli tuff with abundant fine-grained carbonatite autoliths and crustal xenoliths, which resemble those in the carbonatite breccia. The aillikite and carbonatite are characterized by low SiO2 (11–24 wt%), MgO (9.5–12.4 wt%) and K2O (

Fieldwork in the Upper Cretaceous (Maastrichtian) Al-Khod Conglomerates in the Sultanate of Oman led to the discovery of a large bone fragment tentatively identified as a partial distal left humerus of a sauropod and an ornithopod dorsal vertebra. The very fragmentary state of preservation of the dorsal vertebra makes specific attribution difficult, but it shows remarkable similarities to the rhabdodontid dinosaurs Rhabdodon and Zalmoxes.

The late Cretaceous-lower Tertiary hydrothermal alteration of serpentinized peridotite in the Semail ophiolite has formed two distinct types of listwaenite. Type I is characterized by the presence of calcite (Type IA) or dolomite (Type IB)+fuchsite±spinel. Type II is dominated by silicate minerals (quartz, chlorite, fuchsite)±calcite+dolomite±magnetite±apatite±plagioclase. Most listwaenites occur as veins along thrust fault zones within the ophiolite melange. High Cr and Ni contents, abundant occurrence of Cr-spinel within a matrix of red-brown ferruginous carbonates within a micro-vein network of goethite, and the relics of mesh texture indicate an ultramafic protolith. Type I and II listwaenites represent different stages of hydrothermal alteration. The mineralogical and chemical distinctions of both types are the response to the extent of the reactions between the protoliths and the solutions leading to different stages of metasomatic replacement. The hydrothermal fluids involved in the formation of Type I listwaenite were enriched in Ca, Mg, and CO 2 , whereas Type II listwaenite bodies were formed from a hydrothermal fluid enriched in SiO 2 . REE and trace elements in both listwaenite types were extracted in part from adjoining peridotite. No Au anomaly in the study areas has been detected.

The Tertiary volcanic rocks of the central and the eastern parts of the Oman Mountains consist mainly of basanites with abundant upper mantle ultramafic xenoliths. The lavas are alkaline (42–43 wt.% SiO2; 3.5–5.5 wt.% Na2O + K2O). They include primitive (11–14 wt.% MgO) features with strong OIB-like geochemical signatures. Trace element and Sr–Nd isotope data for the basanites suggest mixing of melts derived from variable degrees of melting of both garnet- and spinel lherzolite-facies mantle source. The associated xenolith suite consists mainly of spinel and Cr-bearing diopside wehrlite, lherzolite and dunite with predominantly granuloblastic textures. No significant difference in chemistry was found between the basanites and xenoliths from the central and eastern Oman Mountains, which indicate a similar mantle source. Calculated oxygen fugacity indicates equilibration of the xenoliths at − 0.43 to − 2.2 log units above the fayalite–magnetite–quartz (FMQ) buffer. Mantle xenolith equilibration temperatures range from 910–1045 + 50 °C at weakly constrained pressures between 13 and 21 kbar. Xenolith data and geophysical studies indicate that the Moho is located at a depth of ∼ 40 km. A geotherm substantially hotter (90 mW m− 2) than the crust–mantle boundary (45 mW m− 2) is indicated and probably relates to tectonothermal events associated with the local and regional Tertiary magmatism. The petrogenesis of the Omani Tertiary basanites is explained by partial melting of an asthenospheric mantle protolith during an extension phase predating opening of the Gulf of Aden and plume-related alkaline volcanic rocks.

Despite significant recent improvements to our understanding of the early evolution of the Order Proboscidea (elephants and their extinct relatives), geographic sampling of the group's Paleogene fossil record remains strongly biased, with the first ~30 million years of proboscidean evolution documented solely in near-coastal deposits of northern Africa. The considerable morphological disparity that is observable among the late Eocene and early Oligocene proboscideans of northern Africa suggests that other, as yet unsampled, parts of Afro-Arabia might have served as important centers for the early diversification of major proboscidean clades. Here we describe the oldest taxonomically diagnostic remains of a fossil proboscidean from the Arabian Peninsula, a partial mandible of Omanitherium dhofarensis (new genus and species), from near the base of the early Oligocene Shizar Member of the Ashawq Formation, in the Dhofar Governorate of the Sultanate of Oman. The molars and premolars of Omanitherium are morphologically intermediate between those of Arcanotherium and Barytherium from northern Africa, but its specialized lower incisors are unlike those of other known Paleogene proboscideans in being greatly enlarged, high-crowned, conical, and tusk-like. Omanitherium is consistently placed close to late Eocene Barytherium in our phylogenetic analyses, and we place the new genus in the Family Barytheriidae. Some features of Omanitherium, such as tusk-like lower second incisors, the possible loss of the lower central incisors, an enlarged anterior mental foramen, and inferred elongate mandibular symphysis and diminutive P(2), suggest a possible phylogenetic link with Deinotheriidae, an extinct family of proboscideans whose origins have long been mysterious.

A new fossiliferous locality is discovered from the upper Eocene Aydim Formation, in Dhofar, Southern Sultanate of Oman. A left ulna of Arsinoitherium is described, and cranial and postcranial specimens found in close proximity are referred to the same taxon. The locality is promising for the recovery of additional fossil specimens. Moreover, the presence of Arsinoitherium in Oman is of biogeographic significance; as the Red Sea did not exist during the late Eocene, these large-bodied animals were able to freely travel between what is now the Arabian Peninsula and continental Africa.

The Jafnayn Formation is an Early Paleogene carbonate unit that crops out widely along the Al Batinah coastal plain of northern Oman. It unconformably overlies the uppermost Cretaceous Al-Khod Conglomerates and is overlain by the Lower to Middle Eocene Rusayl Formation. The Jafnayn Formation is informally divided into two members that are separated by a biostratigraphically identified unconformity. The lower member comprises an upsection sequence of low to moderate energy, inner-shelf to lagoonal strata of (1) mudstones and wackestones, (2) massively-bedded, pseudonodular, bioturbated wacke-packstones, and (3) bioclastic mudstones. The lower member is dated as Late Palaeocene (Thanetian) based on the occurrence of the foraminifera Lockhartia diversa, Daviesina persica, Kathina sp. and Nummulitoides margaretae (NP8?). The upper member is Middle to Early Eocene (Ypresian) as suggested by the occurrence of Sakesaria cotteri, Heterostegina ruida and Nummulites globulus. It comprises coral and red algal-rich, well-bedded, occasionally rudaceous, nodular packstones-grainstones and cross-bedded calcarenites deposited in a shallow (less than 10 m), fairly high-energy open-marine shoal environment with nearby patch reefs supplying coral debris. The base of the upper member is marked by a locally distinctive thin (1–3 m) pebble bed rich in various siliciclastic grains and clasts reworked from the underlying member. The pebble bed was deposited immediately after a distinctive depositional hiatus corresponding to the upper part of the Upper Palaeocene and lower part of the Lower Eocene i.e. approximately two nannoplankton zones (NP9–NP10) representing the upper part of the Alveolina (Glomalveolina) levis zone to the lower part of the A. ucumiformis/ A. trempina zones. Although this hiatus is recognised lithologically and biostratigraphically at Wadi Rusayl, at other localities it is only detected through detailed micropalaeontological analysis.

Vegetation abundance in and around Sultan Qaboos University (SQU), Muscat, Oman and its response in Geoeye-1 high resolution imagery are studied using different image processing methods namely band ratioing, parallelepiped, Normalized Difference Vegetation Index (NDVI), Principal Component Analysis (PCA), Minimum Noise Fraction (MNF) and linear spectral unmixing. The developed band ratioing using the near infrared band (B4) as numerator, divided by visible bands (B2 and B3) shows the vegetation are highly reflective in the near infrared and absorptive in the visible bands. The RGB images produced using PCA uncorrelated output bands with the band of NDVI and the MNF inherent dimensional bands with the band of NDVI determined the more representative components for vegetation based on the spectral variations. The PCA and MNF bands processed by linear spectral unmixing shows a plausible coherence with the field observations, proving that the processing strategy applied on multispectral data is useful for vegetation abundance analysis in the study area. The assessment of accuracy for the occurrence and spatial distribution of vegetation provided the overall accuracy of 100% with Kappa Coefficient = 1 in the matrix of parallelepiped and compared with the Spectral Angle Mapper (SAM) and Spectral Information Divergence (SID) algorithms. The evaluation of the results was done by visual comparison and accuracy assessment of the classified images and the field/ancillary data.