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Abstract the preant Work &1maat, evaluating the nature of interference between tbe deltaic sediment. and the desert soils of the eastern border of the Nile Delta. To·tollow the possible variations 10 such area, t~elve protiles were selected alOOI three lines traversing the studied area in easte’.rn and north easterl1 di.rections. The1 st. .~ traverse extends t1”OllDikernls eastwards to El-Tina ”a.ad il-Tina plain. The •• cOl1dtraver •• ext.enda trom Z&18z1g north eastllards to Bl-8alh1a and West Ka.ntara. Also, the 3 -rd-. traver.. extends from Toukheastwards to Belbe1st lad1 Il-Tum.il,at and ends at Abu SWlr •. The studied profiles were thoroughly examined , morpbologlcal11~ described, and ’+6 samples represent1n.g the var1at1Olls throUChollt their entire depths ~8re collected. the •• 8amples were subjected to pby’.lcal, chemical ~d mineraloglcal investigations. fbe obtained results could be sWllD&rized as tollows t 1. M~chan1cal composition. reveals that the protiles or tho 1 !!. traverse line are clay-textured. Those or the ? 2~. traverse Une are 108117 sa.D.d to s11~ clay ( 1n zagaz11 ) a.nd change ’to aaad7 tex’bu’e aaatvards, except the layers or profUe 6 or Kl-8alh1a who•• texture 1s clay- The 3 -rd-. traverse 11ne includes the clay protile at Toukh changing to sandy-textured protiles, except protile 11 or EI-TUmeilat depression which displays apparent texture dlscont1nuit,v. 2. Total carbonate content attains its~ highest value at Dikernls, where 1t ranges trom 2.,8 to 10.32%, while the other protiles, regardless ot their localities, shoWlow contents ot total carbonate, ranging from traces to ~.67~. It shows no specific pattern that could be used tor 80il d1tterentlatlo.n. 3. Organic matter co.o.tent ls generally ve’l’7 low. It ranee. troaa aa low aa 0.01 to 1.81$ due to the prevailing arid1 t1 which contribute. eftectivel, to its rate ot decompo8itlOll, thus dalni.hes its conten’” in the 80118 ot the studied area. It. So11 reaction (pH) 11. quite variable along the stud1ed traverse linea. Though He,ll rea~tlo.n 18 slightl)” to mildly alkaline in most prof11(s, yet protile 2 (El-Tina) and 3 eEl-’lina plain) are nellcral to slightly acid. This ”,as explained OA the preaj,t.e that these latter solIs are saline-alkali, cl1splarLng some a:tages or deterioration. In addition, the preu41C8 ot gypsUill either in the torm ot crystauaria or 8Ab1(.rite .a7 attect. their so11 reaction 5. So1l sal1n1’t7 al’(,WS ita highest level e152-25Ommhos/em.) at El.~1na and El-~1na plain protiles, whereas the lo~est level 1s characterizing the sandy soils at Belbels, West EI_Kantara and the stratif’ledprof’11e ot Wadi El·TUIlel1c1t. With respect to the lateral pattern ot s811n1 ty along th~ studied traverse lines, data indicate that salinity incrt’ eases eastward along tbe 1 -s-t. traverse. Along the 2 n-d~. traverse, however, soil salinity decreases until reaehin! its lo~est level at West El-Kantara• SolI sa11n11y along the 3 -r-d. traverse 11ne, .shOWls a alight decrease on pBss •• ing trom Toukh to Belbe1s and Wadi EI-Tumellat, tollo~ed by a relative increase at Abu Swire Topographical variat- 10ns encoWlUred throughout the studied area 1s shown to play an 1mport~t role in 8011 sBllnization. 6. Exchanae charac .• :r1stiC8 indicate that the .value ot ~ C.E.C. ranges tram 3.2 to ;7.0 me/lOOg depending on &011 texture. Exchangeable ca dominated the exchangeable cations or the Nile alluvial salls and most ot the investigated protiles, while ~ dominated those of El-T1n8 and El-tina plain. Exchangeable cations follow the patterns, Kg> Na> Ca> K tor the tormer and latter s011s, respectively. At Abu Swir, however, Ha predolJl1nate,ex~hangeable cat~.on followed bY’Ca, Me &Ad K. 7. The.~ntent oramorpbous inorganic materials varies considerably trom one protile to another. Generally,s111ca 1s the most abwu1ant,tollowed by iron,While al.umjna 1s the least. Along the 1 -s-t. traverse line, amorphous silica and iron are quite high ,at Dikernis ~d decrease on the ’border tringe. Along the 2-n-d. and 3 r-d-. traverses, amorphous iron tollows a trend characterized by.continual decrease on passing eastwards. Other amorphous materials, however, have no specific trend. &!gh~__!!n!!!!! t These minerals constitute more than 89.6% of the sand minerals. They are dominated by quartz which torms more than 97% or the light mineralh The other associated minerals are related to feldspars which are dlstinguiaped into orthoclase,plag1oclase and microcllne. The predominance ot orthoclase ~ong this group is remarkable. Computation of the weighted mean (profile mean) indicates that orthoclase increases progress1vly eastward along the 1 -s-t. traverse, while it d08S not tollow any trend with respect to other traverses. The presence ot t.ldsp8rs leads to the suggestion that the stUdied soils are young trom the pedological point of view. ~~!y_~!g!!!!!Th!e content and distribution of these mLnerals vary considerably from one protile to aoother and even in the subsequent layers or the same pro tile • Weighted meSA or opaqu.es along the 1 st. traverse indicates a tendency of slight increase on passing from the n.lta to the eastern tringe. Along the 2!!g. and 3 !2· traverses, opaques tend to increase abruptly on moving toward the eastern border. Augite 1s the most representative of pyroxene” it constitutes more than 90% ot such minerals. Its protile mean indicates an 1nc,;re8se eastward along the 1 ,~. traverse, while it decreases north-eastward $longthe 2.!l4. and 3 Eg. traverses. Hypersthene and. d10pside are absent in ~he deltaic sediments ot Dikern!s, zagazlg and ’roukh, ’While 1t appears in those ot the eastern tringe. Hornblende, which 18 tb, most predominant amphibole, shows a general decreasing tendenC7 on pas.ing· from the Delta eastward. or north-eastwards, Glaucophane· shoWI a tendenc1ot decrea.e on passing e8stli8rd or northea8tw~ rd along the 1 ~. and 3 ~. traverse 11nes, ~hlle’ 1t 1I1creases along the 2~. traverse. Epidote group 1s represented by epidote, z01a1te and cl1nozois1 te. Weighted mean or epidote shows a distinct pattern of decrease on passing along the 2 D4. traverse trom zagazlg, while an opposite tr-od i8 maintained along the 3 £9. traverse. The 1!!. traverse, however, displays a rluctu~tlng trend With resg8ct’ to that mineral. Prof118 !Deans tor zircon is char.ct&rized by an increase in that mlneral,on passing trom the Delta eastwards along the studied three traverses. Witl11.o. the studied travers.a, rutile is absent in some pretl1 •• er lay&ra while displays an irrigular distribution in the others. Tou~allne distribution reveals no specific pattern pertaining to locality nor to soil depth. Tne latter three minerals indicate an apparent discontinuity ot the studied profiles, even those repra’8Ating the deltaic sediments. This is explained on basis ot the v~iation. in multi-depositional regime or the deltaic sediments and/or tne multi-origin or sediments in the eastern border. computation or weathering ratios. indicates that Wr 1 and figure index are the most suitable ratios. Wr1 reveals that the delt_ic sediments display similar values which are q,uite different from. those consti tutlng the eastern border ot the Nile Delta. This 1s also evident from the figure index, however it sho~s some discrepancy Within the deltaic sediments. ~!2!!!!2’l_2!_g!!I_~£!g~!22~ The data sbows that lnter$tratifled minerals and/or mont- !porillonl te dominate the 1~.Layminerals suite or the stUdied clars, irrespective of lo:~ation. Other associated minerals, - however. var.y with locali;y, are commonly identified as hydrous mica, kandi tet virmlcull te and chlorite. S£~!!£!T!h!e c18) fractions of soil ~rorl1es located along this traverse are dominated by Interstratlf1ed minerals. ~ectlte’montmor1l1onlte} dominates the clay trac~ tion of Dikernia, while it only dom1nates ia some layers of protiles locatedeastw8rds along that traverse. Hydrous mica is present as a second predominant clay mineral. Kandlt8(kaollnite) is a180 detected in moderate to rew quantities. Vermicul1te and chlor1te are commonly present in traceable amounts. This identical pattern of clay mtnerals SUite, may 10 tact suggest a unique origin or parent material, mainly the deltaic deposits. The minute variation, within the profiles are attributed mainly to the depositional regime a~ well 8S the local environments ot each profile. -2--n-d-.---t-r-a-v-e-rs..e_r--mineralogical data indicate a marked change on passing eastward trom El-Zagaz1g. In tact,the dominant minerals ot the deltaic sediments are changeable as in El-Salhi8t where smectite(montmorillon1te) 1s shown to be the dominant. The differences in clay minerals assemblage are a true reflection of the multi-origin ot sediments in El-Salhia as well as the multI-depositional regimes prevailed in the area during soils formation. J_~g~_!!!~!!!!Th!e clay fractions of soil profiles located along this traverse are characterized by the dominance of interstratif1ed minerals + smectlte(montnorillon1te) and 1s somewhat disturbed on passing north east~ards to Wadi EI-Tumellat and ~bu Swir. The mineralogy of clay in the latter sediments is dominated by interstr8tltled minerals tollo~ed by smectite(monbnorillonlte),l.e., deltaic snd probably lacustrine and aeolian deposits. Noteworthy to mention that the multi-origin ot sediments 1n the eastern-fringe and/or the multi-depositional regime have had their influence on the accessory minerals assemblage, as all of them, except quartz, d1splay discontinuity throughout the entire depth of the studied profiles. |