scholarly journals Study of Heavy Minerals from the Vjosa and Mati river delta sediments in Albania

2020 ◽  
Vol 56 (1) ◽  
pp. 223
Author(s):  
Emiriana Xhaferri ◽  
Ruben Corijn ◽  
Agim Sinojmeri ◽  
Rudy Swennen ◽  
Çerçis Durmishi

This research is focused on the determination of the heavy minerals (HM) load of the Vjosa and Mati river delta deposits along the Albanian coastline and it is based on X-ray Diffractometry. The Albanian coastline consists of sandy beaches at the north (Adriatic coastline) and rocky escarpments at the south (Ionian coastline). Several layers of heavy mineral deposits, up to 50 cm thick, with heavy mineral fraction up to 95% and 88% of total sample for Vjosa and Mati sediments respectively, are identified. The layers enriched in heavy minerals from Vjosa delta deposits are almost black in colour, while at Mati delta these layers are dark green coloured. Separation of the heavy from the light fraction was performed, in order to compare the different fractions between the two studied delta areas. The accumulation of HM occurs mainly in the fraction of 125-250 µm in the sediments of both deltas. The HM dominate in the magnetic field of 0.4-0.8 A/m. XRD analysis results show a great variety of minerals present in the delta samples which can be attributed to the wide variety of geological zones and lithologies that are intersected by the Vjosa and Mati rivers, respectively. In the 63-425 μm fraction rich in heavy minerals of both delta systems considerable amounts of magnetite (up to 39.4% in Vjosa samples), chromite (up to 20.2% in Vjosa samples), garnet (up to 13.6% in Vjosa samples), ilmenite (up to 8.3% in Mati samples), rutile (up to 4.7% in Mati samples), hematite (up to 2.2% in Mati samples), and zircon (up to 2.1% in Vjosa samples) are observed. Rock forming minerals such as pyroxene, amphibole, and epidote compose significant percentages of this fraction. In addition, the presence of gold grains in Vjosa delta sediments is remarkable. Both catchment areas consist to a great extent of similar formations such as the Mirdita Ophiolite Zone and the Pindos Ophiolite complex, providing thus a similar HM fingerprint at both delta areas. Minerals that occur in higher abundances reflect the extensive presence in the drained areas of related parent rocks which are rich in these minerals and which are often more vulnerable to weathering. The samples of Vjosa river delta show high percentage of carbonate constituents, which is related to the presence of carbonate rocks of the Ionian and Kruja tectonic zones within which the hydrographic network of the Vjosa River has been developed. The samples of Mati river delta show lower abundance of carbonate minerals, reflecting the limited presence of carbonate rocks at the Kruja Zone, which occur in the catchment area of the river near its mouth.

GeoArabia ◽  
2004 ◽  
Vol 9 (4) ◽  
pp. 77-102 ◽  
Author(s):  
Mahbub Hussain ◽  
Lameed O. Babalola ◽  
Mustafa M. Hariri

ABSTRACT The Wajid Sandstone (Ordovician-Permian) as exposed along the road-cut sections of the Abha and Khamis Mushayt areas in southwestern Saudi Arabia, is a mediun to coarse-grained, mineralogically mature quartz arenite with an average quartz content of over 95%. Monocrystalline quartz is the dominant framework grain followed by polycrystalline quartz, feldspar and micas. The non-opaque heavy mineral assemblage of the sandstone is dominated by zircon, tourmaline and rutile (ZTR). Additional heavy minerals, constituting a very minor fraction of the heavies, include epidote, hornblende, and kyanite. Statistical analysis showed significant correlations between zircon, tourmaline, rutile, epidote and hornblende. Principal component R-mode varimax factor analysis of the heavy mineral distribution data shows two strong associations: (1) tourmaline, zircon, rutile, and (2) epidote and hornblende suggesting several likely provenances including igneous, recycled sedimentary and metamorphic rocks. However, an abundance of the ZTR minerals favors a recycled sedimentary source over other possibilities. Mineralogical maturity coupled with characteristic heavy mineral associations, consistent north-directed paleoflow evidence, and the tectonic evolutionary history of the region indicate a provenance south of the study area. The most likely provenances of the lower part (Dibsiyah and Khusayyan members) of the Wajid Sandstone are the Neoproterozoic Afif, Abas, Al-Bayda, Al-Mahfid, and Al-Mukalla terranes, and older recycled sediments of the infra-Cambrian Ghabar Group in Yemen to the south. Because Neoproterozic (650-542 Ma) rocks are not widespread in Somalia, Eritrea and Ethiopia, a significant source further to the south is not likely. The dominance of the ultrastable minerals zircon, tourmaline and rutile and apparent absence of metastable, labile minerals in the heavy mineral suite preclude the exposed arc-derived oceanic terrains of the Arabian Shield in the west and north as a significant contributor of the sandstone. An abundance of finer-grained siliciclastic sequences of the same age in the north, is consistent with a northerly transport direction and the existence of a deeper basin (Tabuk Basin?) to the north. The tectonic and depositional model presented in this paper differs from the existing model that envisages sediment transportation and gradual basin filling from west to east during the Paleozoic.


Clay Minerals ◽  
1984 ◽  
Vol 19 (3) ◽  
pp. 287-308 ◽  
Author(s):  
A. C. Morton

AbstractIntrastratal solution of detrital heavy minerals in North Sea Tertiary sandstones takes place in two different diagenetic settings, deep burial and acidic weathering. These are characterized by different orders of mineral stability: apatite, chloritoid, garnet, sphene and spinel are less stable in acidic weathering than in deep burial, whereas the reverse is true for andalusite, kyanite and sillimanite. Heavy-mineral dissolution patterns, therefore, do not follow one single order of stability but several, depending on the diagenetic environment in which the dissolution occurs. It seems from this that the relative order of stability for detrital heavy minerals is controlled by the chemistry of the interstitial waters, whereas the limits of persistence depend on pore-fluid temperature, rate of water throughput, and geological age. Because different diagenetic environments lead to differing orders of mineral stability, it may prove possible to elucidate certain aspects of the diagenetic history of a sandstone by heavy-mineral dissolution patterns.


2020 ◽  
Vol 90 (12) ◽  
pp. 1747-1769
Author(s):  
Xavier Coll ◽  
David Gómez-Gras ◽  
Marta Roigé ◽  
Antonio Teixell ◽  
Salva Boya ◽  
...  

ABSTRACT In the Jaca foreland basin (southern Pyrenees), two main sediment routing systems merge from the late Eocene to the early Miocene, providing an excellent example of interaction of different source areas with distinct petrographic signatures. An axially drained fluvial system, with its source area located in the eastern Central Pyrenees, is progressively replaced by a transverse-drained system that leads to the recycling of the older turbiditic foredeep. Aiming to provide new insights into the source-area evolution of the Jaca foreland basin, we provide new data on heavy-mineral suites, from the turbiditic underfilled stage to the youngest alluvial-fan systems of the Jaca basin, and integrate the heavy-mineral signatures with available sandstone petrography. Our results show a dominance of the ultrastable Ap-Zrn-Tur-Rt assemblage through the entire basin evolution. However, a late alluvial sedimentation stage brings an increase in other more unstable heavy minerals, pointing to specific source areas belonging to the Axial and the North Pyrenean Zone and providing new insights into the response of the heavy-mineral suites to sediment recycling. Furthermore, we assess the degree of diagenetic overprint vs. provenance signals and infer that the loss of unstable heavy minerals due intrastratal dissolution is negligible at least in the Peña Oroel and San Juan de la Peña sections. Finally, we provide new evidence to the idea that during the late Eocene the water divide of the transverse drainage system was located in the North Pyrenean Zone, and areas constituted by the Paleozoic basement were exposed in the west-Central Pyrenees at that time. Our findings provide new insights into the heavy-mineral response in recycled foreland basins adjacent to fold-and-thrust belts.


2021 ◽  
Vol 61 (2) ◽  
pp. 688
Author(s):  
Stuart Munday ◽  
Anne Forbes ◽  
Brenton Fairey ◽  
Juliane Hennig-Breitfeld ◽  
Tim Breitfeld ◽  
...  

The Early Permian in the onshore Perth Basin has experienced several significant discoveries in the last 8 years. Beginning with the play-opening Waitsia discovery (AWE), this was followed more recently by the Beharra Springs Deep (Beach Energy) and West Erregulla (Strike) discoveries. In addition, Late Permian sands (Dongara and Wagina sandstones) have long been recognised as excellent reservoirs in the basin. This study attempts to better understand the provenance of the Early and Late Permian sediments using automated Raman spectroscopy as a tool to identify variations in heavy mineral assemblages. Automated Raman spectroscopy analysis of heavy minerals minimises operator bias inherent in more traditional optical heavy mineral analyses. These data are integrated with publicly available chemostratigraphy data to enable a better understanding of sediment provenance variations with stratigraphy. In addition, publicly available detrital zircon geochronological data are incorporated to help further understand sediment sources. A transect of wells is investigated, from Arrowsmith-1 in the southernmost extent to Depot Hill-1 and Mt Horner-1 in the north. While the elemental (chemostratigraphy) data suggest some changes in sediment provenance through the Permian of the Perth Basin, the Raman heavy mineral data confirm a number of sediment provenance changes both at key formational boundaries (e.g. top Kingia sandstone) and complex sediment provenance variation within reservoir sandstone units. These results are integrated to demonstrate how sediment provenance holds the key to understanding controls on variable reservoir quality as well as understanding the early infill in this basin.


1982 ◽  
Vol 119 (5) ◽  
pp. 463-476 ◽  
Author(s):  
A. C. Morton

SummaryThree heavy mineral associations have been recognized in Palaeogene sands from the Hampshire Basin: one typical of the Scottish Highlands to the north, one of the Armorican massif to the south, and one characteristic of the Cornubian massif to the west. These associations interplay throughout the sequence to produce 10 heavy mineral units correlatable over the basin. The bases of several of the units correspond to commonly accepted time-surfaces and encourage correlation between areas showing strong facies variation. Transgressive units are dominated by Scottish-type material, regressive units by Armorican or Cornubian detritus. There is a relationship between local source area uplift and regression, the main reason for which is that the widespread transgressions submerged or otherwise cut off more local sediment sources, allowing input from the Scottish Highlands, a positive feature throughout much of Tertiary time, to dominate.


1993 ◽  
Vol 30 (3) ◽  
pp. 553-574 ◽  
Author(s):  
Frances J. Hein ◽  
James P. M. Syvitski ◽  
Lynda A. Dredge ◽  
Bernard F. Long

Offshore areas, along the North Shore of the St. Lawrence Estuary, have major lithostratigraphic and seismostratigraphic units that relate to the advance or retreat of the Late Wisconsinan Ice Sheet, subsequent marine transgression or regression, and reworking of postglacial deposits. Glacial diamicton and glaciomarine units (acoustic units 1 and 2) were emplaced between >18 and 14.5 ka, by basal meltout or ice-marginal sedimentation; they reflect ice-proximal sedimentation associated with ice-terminal stillstands. Deep-water muds (acoustic unit 3) represent ice-distal accumulation of glaciomarine sediment from glaciofluvial plumes between 13.5 and 11 ka. After this time exceptionally thick nearshore coarse-grained deltaic and estuarine successions (acoustic unit 4) were deposited. The uppermost postglacial sediment (acoustic unit 5) forms the seabed and reflects a reworking phase concomitant with a lowering sea level and ablating Late Wisconsinan ice sheets.Glacioisostatic rebound, which occurred about 23 ka to the present, uplifted glacial and marine deposits and resulted in extensive reworking and production of modern placers. Heavy-mineral concentrations vary as follows: terrestrial tills, 9–20%; modem storm-berm and delta top deposits, 43–60%; delta slope deposits, 25–55%; and deep (170+ m) offshore sediments, 0–2%. Three stages occurred in marine placer formation: (1) 6700 BP, fluvial discharge was high, and fluvial-dominated deltas were built; marine limit was 30 m asl, with progradation of deltas and delivery of sediments with at most 2% heavy minerals; (2) 5200 BP, fluvial discharge was reduced; marine limit was 15 m asl, deltaic sediments were reworked, increasing heavy mineral concentration to 2–8%; (3) 2800 BP, fluvial input was greatly reduced, waves and tides were more influential, a strong littoral current system developed, causing significant reworking of nearshore sediments, heavy mineral concentrations increased, with values exceeding 20% locally. Mass budget calculations show that the second-cycle reworked sediment (acoustic unit 5) is a potential economic target (1 km3, or 1700 Mt). If 7% (using atomic weights) of this target sediment is ilmenite (FeTiO3). then 27 Mt of titanium may be available.


Geologos ◽  
2013 ◽  
Vol 19 (1-2) ◽  
pp. 147-158 ◽  
Author(s):  
A.N. Derkachev ◽  
N.A. Nikolaeva

Abstract The possible reconstruction of ancient sedimentary environments on the basis of heavy-minerals assemblages is presented by means of discriminant lithogeodynamic diagrams that compare modern and ancient sedimentary environments. This is exemplified by Mesozoic-Cenozoic deposits recovered from ODP cores obtained from the Philippine and Japan Seas, the Japan Trench and the North Atlantic, as well as by deposits from folded areas onshore. On the basis of the comparative analysis, it can be deduced that the main tendencies in mineral assemblages of modern deposits that depend on the structural-tectonic conditions, are fairly well preserved in Cenozoic deposits (including the deposits recovered by ODP drilling). On the other hand, the environmental reconstruction of folded and faulted pre-Cenozoic continental areas on the basis of their heavy-mineral assemblages, by comparing them with supposed modern analogs, is not always possible with much certainty. The main reasons may be either a considerable change in the composition of the initial (primary) mineral assemblages as a result of intralayer solution or the absence, at the time of deposition, of geodynamic environments that closely resembled modern ones.


1980 ◽  
Vol 17 (2) ◽  
pp. 244-253
Author(s):  
John Edward Callahan

Stream sediments from a 13 000 km2 previously glaciated area in central Labrador near Churchill Falls were examined for their heavy mineral content. The minus 0.25 mm (60 mesh) nonmagnetic heavy mineral fraction from 846 stream sediment samples consists mainly of magnetite, ilmenite. garnet, hornblende, epidote and minor clinopyroxene, orthopyroxene. kyanite. sillimanite, biotite. apatite, and zircon. Changes in the frequency distribution of epidote, hornblende, garnet, and sillimanite in the stream sediments correspond well with those reported in previously mapped underlying bedrock lithologies. The occurrence of kyanite and sillimanite, high concentrations of garnet and opaques (mainly ilmenite), and lower concentrations of hornblende and epidote were used to determine grades of regional metamorphism, resulting in revision of the geologic map of this area. Heavy minerals in glacial drift or fluvial deposits may be useful as an aid in mapping in glaciated areas.


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