Age and Chemical Composition of Тне Zнaмanshin Crater Impactites and Tektites Cqmparison with Australasian Tektites

E.Izokh, L.каshkаrоv, N .коrоtkоvа

AGE AND CHEMICAL COMPOSITION OF ТНЕ ZНAМANSHIN CRATER IMPACTITES AND TEKTITES AND CQMPARISON WITH AUSTRALASIAN TEKTITES

Novosibirsk 1993 RUSSIAN ACADEMY OF SCIENCES SIВERIAN BRANCI:I UNIТED INSTIТUTE OF GEOLOGY, GEOPНYSICS AND MINERALOGY

E.Izokh, L.Kashkarov, N.Korotkova

AGE AND CHEMICAL COMPOSITION ОР ТНЕ ZHAМANSHIN CRATER IMPACTITES AND TEKTITES. AND COMPARISON WITH AUSTRALASIAN TEKTITES

NOVOSIВIRSK 1993 E.Izokh, I,.каShkагоv N .Korotkova. A�e . and chemical composition of the Zhamanshin Crater ...lmpactites and Tektites and comparison with Australasian Tektites. NovosibIrSk, 1993. 94 р.

ISBN 5-7323-1784-6

ТЬе Zhamanshin impact ci'ater is the only impact crater оп the Earth where impactites, various tektites and microtektites coexist. Тhus t�e Crater becomes the best object to solve the old tektite puzzle. Published before and new data оп the radiogenic ages and chemistry of the Zhamanshin tektites and Australasian tektites summarized to demonstrate their close genetic relations. ТЬе tektite age-paradox �erves as the base evidence in favor of the exstraterrestrial origin of tektites. Тhe petrographical and petrochemical features of tektites demonstrate their most рсоЬаЫе volcanic origin.

ISBN 5-7323-1784-6 © E.P.Izokh, UIGGM, 1993 L.Firsov (Novosibirsk) was the first to obtain < 1 т.у. K-Ar age of the Zhamanshin acid glasses. V.Perelygin фиЬпа Inst. of Nuclear Physics) obtained 0.81 +0.16 т.у. fission track age of the same glasses (Florensky et аl, 1979). 1.07+0.05 and 1.07+0.06 fission track ages of the acid zhamanshinites and irghizites respectively were obtained Ьу Storzer and Wagner (1977, 1979). Following Florensky and Dabizha (1980, р. 32), the age of the Zhamanshin crater was determined between 0.69-0.85 т.у. Ьу five independent methods: Ьу stratigraphy (Iess than 25 т.у.); Ьу geomorphology (05-1 т.у.); Ьу K-Ar dating « 1 т.у.); Ьу fission .track dating (0.65-0.75 т.у.), and from reverse magnetization of the impactites (0.69-0.85 т.у.). Al1 these data served as the base for the most recent judgement оп the crater age because по other il1terpretation was permitted Ьу the EIТ. S.Taylor and S.McLennan (1979, р. 1551) noted а close compositional resembIance between Zhamanshin acid glass and НепЬигу impact glass, which "has, Ьу chance, а composition identical for most elements to australites". They saw in the irghizites "а parental material similar {о terrestrial subgraywacke, Iike that at the НепЬигу target rocks, while basaltic andesite is а Iikely source for the basic zhamanshinites" (ор. cit., р. 1558). "The chemical and possibIe age similarities between the irghizites and the Australasian tektites are sufficiently close to warrant а detailed investigations" (ор. cit., р. 1555), and "estabIish the Zhamanshin structure as а possibIe source for the Australasian strewn field" (р. 1563). V.Bou�ka also studied P.Florensky's samples, but suggested that platform cover, i.e. the Paleogene sands and clays, served as the precursor of the various Zhamanshin glass (Bouska et al,1981). After Р .Florensky's researches the investigations of the crater were supported Ьу the Siberian Branch of the Academy of Sciences and continued Ьу E.Izokh (1984). Later, V.Masaitis, V.Feldman, Ja.Boiko and other geologists were invited to participate in the research Program. Three bore holes of -1 km deep were drilled within the crater fu nnel Ьу regional geological survey (Aktyubinsk) under the auspices of the аЬоуе Program. From the beginning E.Izokh noted unusually young morphological features of the crater and the close resembIance between acid zhamanshinites and Muong Nong-type tektites (MN-tektites) from Vietnam, as we]J as the absence of proper target rock for tektites (lzokh, 1984; Izokh et al, 1984) . . V.Masaitis, оп the other hiшd, as а staunch supporter of the EIТ, tried to find compositional analogues in the Paleozoic beds, but not in the sediment cover, which, from his point of view, did not participate in the impact melting process

4 INTRODUCTION

ТЬе Zhamanshin impact crater (North of Aral Sea) is the only one where at least 3 different types of melted glass are found 'together: 1 - impactites, 2 - various layered Muong Nong-type tektites, 3 - tektites-irghizites associated with microtektites, ТЬе well known tektite age-paradox (the great difference betwee� the age of tektite formation and their geological position) is widely recognized as an argument in favor of the extrateri'estrial origin of tektites, Thе close genetic relation between the Zhamanshin crater and the Australasian tektite strewn fieId (ААTSF), as evidence of their simultaneous origin, is also clearly recognized, ТЬе currentIy dominant Earth Impact ТЬеосу (ЕП) does not' explain the аЬоуе and many other data, Thеalternative extraterrestrial volcanic hypothesis proposed Ьу J.O ' Keefe (1976) seems more suitable. Some corrections based оп the tektite age-paradox are necessary, however. Thus, the discussion, now more than l00-year old, оп the origin of tektites continues. ТЬе Zhamanshin structure represents in itself an excellent testing ground оп which to develop the discussion, and to check and to compare the rival ideas of impact cratering, the origin of the tektites, catastrophic global changes connected with the tektite faB, etc.

HistoryоС the Zhamanshin Crater Study

ТЬе basic data оп the Zhamanshin crater: geology, age, target rocks and various glass composition are to Ье found in Florensky and Dabizha (1980); Вошо (1983); Izokh (1984-1991); Masaitis (1987-1991).1t was Florensky (1975) who first recognized the crater as an impact structure and distinguished three main types of glass: basic zhamanshinites, acid zhamanshinites and tektites� irghizites. Florensky suggested that the basic zhamanshinites originated from various target rocks, including those from the paleozoic and tertiary formations. Не considered the acid zhamanshinites as completely melted paleozoic quartzite-slates, while the irghizites were regarded as formed Ьу condensation and accretion of the melt droplets within an incandescent gas cloud, where evaporated slates and meteorite were mixed (Florensky ' and Dabizha,1980).

3 (Masaitis and Selivanovskaya, 1987; Masaitis, 1989). In general, Ье fo11owed the рзth laid out Ьу Р j<'lorensky. V.Feldman used а statistical cluster method to compare the chemicaI composition of target rock and glass. Не concltided that' а11 types of the Zhamanshin glass Ьауе chemical analogues in the basement and in the platfol"ffi cover, as well. ТЬе most likely source material for tektites, Ье considered, was the superficial loess-like cover. V.Feldman underlined the most unusual feature of the Zhamanshin crater: that is, the formation of various compositional groups of gIass, quite distinct from the homogenization of the target rock соттоп to other well studied impact structures. At present, аН participants of the �rogram unanimously admit the impact origin of the basic zhamanshinites Ьу rrielting of the carbonic (С1) andesite volcanicS. With respect to the origin of the acid gIass, significant disagreement remains.

Previous Age Determinations

ТЬе first age determinations were applied only to the acid gIass (table 1, 1-4). ТЬе basic impact gIasses were analysed later'by L.каshkагоv et аl (1986) оп the request of E.Izokh. As it was anticipated, the fission track age of the basic impactites turned out to Ье one or two orders of magnitude Iess than that of the acid gIass « 0.1 т.у. vs - 1 т.у.; tables 1, 2). ТЬе same speciniens were analysed Ьу Е.коlеsпikоv (Moscow U!1iversity) and Ьу D.Storzer (Museum of Nat. History, Paris). As L.Kashkarov's results were doubted Ьу these researchers, а dramatic discussion arose; the course of this, discussion is ihstructive. E.Kolesnikov et аl (1988) found 153-1.66 т.у. K-Ar age of'the basic impact gIass (table 2). Nevertheless, 1.1 т.у. age was inferred, following the К Ar isochron. Unfortunate\y, incompatible data were plotted оп the diagram to align the isochrone. As fig. 1 shows, only acid gIass data Ьауе s\gnificantweight to give the slope of the isochron confirming 1 т.у. age of the tektites alone, but not impactites. Matsubara et aI. (1991) also found rather oId 0.99 т.у. age of the basic gIass, which, as they write, "is in agreement with the corrected fission track age of 1.07- т.у." obtained Ьу Storzer and Wagner (1979) and Ьу Koeberl and Storzer (1987). However,the value of К2О = 2,67% was erroneously used for the age calculation in this case. In fact, К2О = 1.43+0.16% (average from 27 analysis) is tyPical of the Zhamanshin basic impact glass, while К20 =

5 2.86 +0.19 (average from 42) is typical only of acid Muong Nong-type g1ass (Izokh, 1986). Therefore, the calculated age for the sample Zh62j3b wШ Ье - 2.2 т.у., which is much older in comparison with апу fission .track ages obtained for Zhamanshin glasses.

Fig. 1. K-Ar isochron of the Zhamanshin glasses: 1 - basic (impactites), 2 - acid (tektites), (see tables 1, 2) (Kolesnikov et al, 1987) .

. / 02

The discrepancies between fission track ages and K.Ar age& are the соmтоп feature of various impactites. This. feature сап Ье easily explained "Ьу incomplete degassing or contamiriation Ьу old source material" (Matsubara et al, 1991, р. 2954). As to tektites, such discrepancies are either absent or less significant; tabIe 1 represents а good example. The basic zhamanshinites, indeed, practically always have numerous target rock inclusions; therefore, misinterpretation of their K-Ar age is easily understood. Contrary to basic zhamanshinites, the acid MN-type zhamanshinites with. rare exceptions (see below), have по impurities of this kind. Thus, their K-Ar ages near equal to the fission track ages could Ье interpreted as the age of tektite formation. From this point of view, the confirmation of the 5.2 т.у. age of acid zhamanshinite (sp. 57j2b) Ьу the fission track measurements seems to Ье of high importance. Quite unexpectedly to us D.Storzer inferred -1 т.у. fission track age of the basic impact glass (tabIe 2, 8-10), however, only after large correction. During the detailed personal discussion with the authors in Moscow in September, 1989, D.Storzer explained that the fission tracks in the basic glasses

6 were уесу small and could Ье observed only with high-quality optical equipments. Не suggested that fission tracks had annealed in the heat of the Sun, in contrast to the supposedly тоге stable acid glasses.

ТаЫе 1 Radiogenic ages о! the acid zhamanshinites .and irghizites

# Specimen Method Age (т.у.) References

1 Irghizites and acid K-Ar < 1.0 F!orensky and zhamanshinites Dabiz�a, 1980 2 - " - Fission 0.81±O.l6 - . - tracks 3 Irghizite · " · 0.99;tO.05:0 Storzer and 1.07;tO·06000 Wagner, 1979 1.08 ±О.l1о " · " · 4 Acid zhamanshinite 0.87;tO·0600 - 1.07 ±О.о.\о 5 Acid zhamanshinite " - 1.1 ±О2 Kashkarov (Zh7/6) et a!1987 · 000 : 6 - " - �Zh20/5) " 0.75±О.1 - . - 7 - " - Zh7/6) K·Ar 1.17±Q.ll Ko!esnikov et a! 1987 8 - " . (Zh20/5) · " · 1.02±о.о9 - � - 9 Yellow pumlce ·" · 120±О27 - " · (Zh37e) 10 Irghizite (Zh11) · " - 3.63 ±О.61 о . " · 11 "B!ue" zhaman- · " · 1 0.91 ±О.о.\о Koeber!and shinite (Zh31/6c) 1.04±О.12000 Storzer, 1987 12 - " - (BZ8601) - " · 1.09±О.14 Storzer and 000 Koeber!. 1989 13 - " - (BZ8602) · " · 1.08±О.14 - · 14 Acid zhamanshinite · " · 0.95 ±О.15 Arake!jants (Zh ) et а!. 1988 " / " - Т - 15 "2.j /1) - 1.oI ±О.15 - ,, - 16 - " - Zh20/1� - " - 0.75 ±О.15 - " - 17 - " - Zh22/1 - " - 0.73 ±О.15 - " - 18 - " - Zh23/1 - " - 0.78±О.15 - " - 19 Acid zhamanshinite Ar-Ar 0.943±О.16 Deino et а!1990 20 - " - (next !ayer) - " - 0.868 ±О.11 - :. - 21 Acid zhamanshinite K-Ar 520±О.84 Matsubara (Zh57/2b) 1991 et al, 22 - " - �Zh36/2) - " - 1.00±О.43 - " - 23 - " - Zh30a) - - " - 0.69±О.07- - " - о 00 000 Apparent a�e. plateau correction, size correction. Specimens with the letter Zh _ from Elzokh s collection. .

ТЬе authors were not satisfied Ьу this adhoc explanation, because spontaneous fission tracks of normal dimensions compared with that of the induced ones. though rare (as а matter of fact single), are well preserved in the

7 basic glass. Therefore, one сап conclude that this glasses did not undergo heating at least during the last 0.01 т.у. This paradoxical situation stimulated us to perform an experiment involving the heating of both types of glasses in order to detect any differences in their thermal stability. Basic impactites taken from the deep bore holes, where solar heating was impossibIe, were also studied. . ТаЫе 2 Radiogenic ages оС the basic impactites-zhamanshinites

# Specimen, # Method Age (т.у.) Ref�rences

'" 1 Basic zhamanshinite Fission < 0.1 Kashkarov (Zh4За tracks et 1,1987 " � 2 - �45a - - 0.1 - - -" �Z � ±о.оз::: " з - ". Zh45e . - " - 0.1 ±О.ОЗ - - 4 - " - Zh45e К-Аг 1.5З±О.19 Kolesnikov et l, 1987 " � 5 - :: - (Zh4За) - - 1.66±О.12 -- " " - - - 6 - - - 1.6З±О20 (ZhЗ9d/З) " " 7 Basic dlaplectite - - 1O.64±Q.O� - - 8 Basic zhamanshinite Fission 038±Q.05 Koeberl and tracks Storzer, " 1987 1.19±Q24: 9 Basic "irghizite" - " - 0.74 ±Q.04" - " - 1.09±О.06",

" 1.12±Q.18", 10 . Basic zhamanshinite - - 0.96±О26 Storzer and (Zh57j4c) Koeberl. +) 1989 11 ." - (Zh62jЗЬ) j K-Ar 0.99±Q.12 Matsubara et al, 1991

See comments to table 1. +) Corrected calculated age is 22 m.y.(see text).

Thermal StаЬШty Study оС the Zhamanshin Tektite and Impactite Glasses

Results of artificial annealing of the· basic and acid Zhamanshin glasses аге presented in fig. 2. It is clear that the basic glass has less therma! stability compared to the acid glass, indeed. However, this difference is o'ne of only - 1.5-2 times, rather than а difference of 1-2 orders of magnitude suggested Ьу D.Storzer. For instance, at то = 400-4500С оуег а time period of опе hour, the fissioI1 l)'acks in the basic glass annealed completely, while approximately 20% of them remained preserved in the acid glass. At то > 5000с the differences Ьесаmе insignificant.

8 Fig. 3 shows the extrapolation of the experimental data over а time 0 period of 0.01-1.0 т.у. at то = 60-90 С, which is the highest suggested level of daytime Solar heating. Under these conditions -40-50% of the fission tra<;ks would Ье preserved in the basic glass, with -70-80% remaining in the acid glass. In order to generate almost complete annealing of the fission tracks (> 90%) in the basic glass, а eontinuous Solar heating over а period of tens of millions years would Ье required.· Moreover, this time period would Ье even longer if day-night, seasonal and climatic changes in Solar radiation were taken into account. Insomuch as the effective exposure to the Sun was hardly mor'� than 0.2-0.3 т.у., the annealing effect cannot Ье explained in this way. IJf/IJo (6'158 1,°1 '-'� I 87-6 620-5 48

40 Acio'

о�-.--.--,г--г--т--т--��--r--,---- ·200 �oo 500 т,�

Fil. 2. Resu!ts of the 252Cf fission tracks experimenta! annea!ing at то = 0-5000с during опе hour. 1 - basic zhamanshinites-impactites, 2 - acid zhamanshinites-tektites. Limits of the observationa! errors indicated.

It is important to note, that аН the above mentioned calculations are valid only for spontaneous fission tracks older than 1 т.у., because heating time will Ье proportionately shortened for the younger tracks. Therefore, we must also take �nto account the various stages of the preservation of fission tracks. х 6asi" о O'"ia'

.907,,60 Tt'

Fig. 3. Extrapolation of Фе basic impact glassexperimental data оп а heating time 0.01-1.0 т.у, at то = 5О-1()()Ос(outer quadrangle), and at то = 6О-9()Ос (inner quadrang1e). Ratio of the fission tracks preserved at the prescribed conditions (in '%) indicated.

10 The fact of exceBent fission track preservation in the acid glass, which are laying together with the basic ones, forced оnе to exclude аnу other possible source of glass heating such as fires, lightnings, etc.

Fission Track Age of Basic Impactites from Deep Вore Holes

. То eliminate the p6ssibility of daytime surface heating, the.specimens of basic glass, especially selected Ьу A.Raichlin and V.Masaitis from the deep bore-hole cores, were examined. ТЬе most suitable samples were glass fragments (without bubbles) from bore-hole # 103 at а depth of 150 т. Three stage etching and polishing was performed оп them to obtain larger surfaces for fission track counting. Nevertheless, only two fission tracks was found in -20.7 тт area. As table 3 shows, the upper limit of the fisiion track age is most probably -0.01 т.у. Thus, the very young time of the basic glass melting Ьесате undisputable from our point of view.

ТаЫе 3 Fission track age of the basic impactites from the deep bore holes

Боrе Uranium Number of Observed Number of Upperage hole #/ content glass area(mm2) spontaneous limit depth (ррт) fragments tracks (т.у.) 101/75 1.6-2.0 12 3.1 О <0.1 101/178 " 8 21 О < 0.1 103/150 -- 21 20.7 2 - 0.01

It is important to note that the whole observed glass area (26 тт2) exceeds Ьу 15-20 times that required for determination of the fission track age of acid glass. ТЬе statistics in this case must Ье applied n6t to comparison of fission track number but only to investigated areas. If this reasoning is correct, then irghizites and acid zhamanshinites nearly 1.0 т.у. old were originated long before the Zhamanshin impact event and arrived оп the Earth mostly intact, as partially preserved projectile material. • V.Masaitis (personal discussion) opposed the above conclusion, because Ье found the acid zhamanshinite fuB of target rock inclusions, mixed with acid

11 glass. This fact V.Masaitis interprets as irrefutable evidence of an impact origin of а11 tektite-like glasses. E.lzokh, in contrast, assumed that this is due to а secondary remelting during the impact. In order to solve long lasting discussion а special "experimentum c1Ucis"was carried out.

Fission Track Age Qf the Tektite-Zhamanshinite Remelted During the . Impact Event

V.Masaitis' specimen represents typical layered bIack-уеllоw tektite zhamanshinite, which is partially preserved within grey pumice replete with target rock inclusions: quartzite-slates, clayish quartzites, transparent vein quartz and diaplectites of these rocks. АН of them are found оп the surface of the crater rim. А piece of black nonvesicular glass was taken from the tektite remnant for study. 32 spontaneous fission tracks were found оп the observed area whkh was investigated Ьу the repolished method. Two groups of them with evidently different diameters were recognized (table 4, fig.4). First group represents the old (pre-impact) fission tracks with the diameter d < 3.J'1-�. Setond group represents the fission tracks with the diameter - 4jLm, that is equal to those induced Ьу the 252Cf fission fragment's source. ТаЫе 4 Fission track age of the acid Zhamanshinite пiixеd with target rocks

Groups of fission Number of Fission track Apparent tracks spontaneous dепsi age,m.y . . fission tracks /ст зу I .f

1 - partly annealed (old) 26 70 > 0.1

II - fresh (post-impact) 6 15 < 0.02

Specimen # �158a-2f was given Ьу V.Masaitis. Uranjum contentz2,5 .± 3р.р.m.; observed . агеа 0385 сm . .

These fresh unaltered fission tracks were undoubtedly accumulated after the impact event, while the fission tracks of the first group were partially annealed during the remeIting of· the glass. As table 4 shows, the lowest limit of the effective age for the first group сап Ье estimated as > 0.1 т.у. The accumulation time of the second group is < 0.02 т.У. Again, this another unexpected result appears to confir!ll the уегу young age of the Zhamanshin impact event. .

12 Fig. 4. Distribution of the spontaneousfission tracks in the remelted acid Zhamanshinites of Muong Nong 20 type.Partial1y annealed fission tracks (1) Ьауе 1-3 m in diameter, while wel1 preserved fission tracks (Пr Ьауе 18 -4J4 m in diameter (equal to that. of the induced fission tracks). 16

�'" 11f -Q 12 с:§ 1j 10 !::s �8 6 '1 2 О О 1 2 5

Thermoluminescence Analyses оС the Zhamanshin Glasses

ТЬе dramatic character of the current discussion forced· us to use ап independent (thermo!uminescent) method of the g!ass age dating. This method is based оп the measurements of the equiva!ent dose of the radiogenic radiation (Deq), at which the i.ntensityof natura! (1"Lnat) and artificia! (ТLart) thermo!uminescense Ьесате equa!. Our first task was to сотрасе Deq of the basic and acid zhamanshinites with known fission track ages. After measurement of the TLnat the glasses were exposed to various doses of r - quantum radiation from а standart radioactive source (137Cs, 60Со). ТЬе dosage ranged from 60 to - 5500 Кrad. ТЬе stepped measurements of the ТL parameters in а process of Deq r accumu!ation allowed us to appreciate the уа!ие of � = ТL r/TL nat which characterized the rate of ТL-ассuпщ!аtiоп in еасЬ specimen, and the value of Deq r. whenq = 1. ТаЫе 5 and fig. 5 show the great. differences in ages (an order of magnitude) between the basic and the acid g!asses. For instance, in the basic impact g!ass 1 = 1 when Deqr= 100

13 Кrad, while in the acid tektite glass � 1 only when Deqf> 1500Кrad or еуеп = 5000 Кrad (fig. 5).

--- � 4, - - - �б � a 1,! �5 �б � 1,4

1,2 ---

! �8

CJq t?4 �2

!С'С' J/J/J .;оо

Fig. s. Ratio variations Iz. = TLart DrП �аt under various doses of D r exposition for basic (sp. 45а, 43а) an(! acid z.namanshinglasses (sp. 20-5, 7-6).

Thus, basic and acid glasses have .the same great differences in ТL-age (time of TL-accumulation), as in the fission track ages.

Paleomagnetic Dating

The Zhamanshin basic impactites have reversed magnetization opposite to the direct опе of the latest (Brunhes) epoch which lasts from 0.69 т.у. ир to the present. This date was compared with the Matuyama epoch of reversal polarization (2.4-0.7 т.у. ago), since it coincides with radiogenic ages of tektites obtained before (Florensky and Dabizha, 1980). Meanwhile, the Brunhes epoch was interrupted several times Ьу short episodes or excursions of reversed magnetization, as well. The latest of them is the Heteborg (Hetenburg) episode

14 ТаЫе 5 Intensity оС the thermoluminescence in basic and acid zhamanshinites in comparative unit оС measurement

Dose of r -radiation, Krad *)

Sp. # TLnat 60 130 620 1440 5500 TLart tz TLart i TLart ,z TLart -1 TLart 1 acid 112 0.5 0.04 0.65 0.06 0.8 0.07 1.95 0.17 12.6 1.1 7-6 acid 7.5 1.1 . 0.15 2.55 0.34 43 0.57 6.0 0.8 21.4 2.8 20-5 basic 2.5 1.6 0.64 2.45 0.98 61 112 43 1.72 20.0 8.0 43а basic 1.8 1.4 0.78 1.95 1.10 4.6 2.55 6.9 3.83- - - 45а

= 137 ;)Prr 60-1440 krad, ('-source Cs of - 1 krad/hour power; О,,= 5500 krad, .r-source со of - 1()()()krad/hour power. of 0.09-0.011 т.у. age (Gurary et al, 1984; Tretyak et al, 1989). This is just the time interval which coincides with the radiogenic ages of the Zhamanshin impactites and with the geological age of the crater. То verify data which had been previously obtained, [оис oriented samples of the basic zhamanshinites were drawn [сот the same impactite bed which v/as sampled before Ьу P.Florensky. The paleomagnetic measurements made Ьу A.Kazansky of the Institute of Geophysics (Novosibirsk) сопПгтрГl the reversed magnetization of the impactites.

Geological Age оС the Zhamanshin Impact Crater

This рсоЫет has Ьееп discussed in detail (Izokh, 1986,1990, 1991; Volkova, 1990). The main '!.rguments [ог the very young age of the crater асе as folIows. Morphological Ceatures . The perfect preservation of the crater rim, composed mostIy of soft сlау and sand, is the first impression recorded Ьу а field-observer. SmalI (50-200 m in diameter) unstable satellite craterlets surrounded Ьу low rim of loams are strikingly well preserved, as well. The dendritic pattern (net) of the temporary streams is Iimited. most1y Ьу the hills of the circular crater rim (see the Landsat MSS images in: Grieve et аl, 1988).

15 Finally, the small (50-200 т in diameter) compact areas of the tektite concentration show по traces of replacement. Perfect preservation of these morphological structures during -1 т.у. after the alleged old impact event is highly improbable, especially if the substantial climatic changes connected with Pleistocene glaciation are taken into consideration. Geomorphological f�atures . Some special investigations performed at oиr request Ьу I.Novikov (1992) did not confirm P.Florensky and A.Dablzha (1980) opinion about > 0.1 т.у. age of the drainage pattern, because of ап uncertainity of the geomorphological dating. Meanwhile; I.Novikov found that' Zhamanshin structиre coincides with ап older circular drainage systeffilocated оп the vast flat table land. У. Masaitis et аl (1991) considered this old morphostructиre of - 13 km in diameter to Ье the outer circular contoиr of the Zhamanshin impact structure, however, without trace of the outer Tim, which supposedly was somehow selectively removed Ьу erosion. Following the work of I.Novikov, Zhamanshin crater is опlу - 6 km in diameter, as was first estimated Ьу P.Florensky ahd A.Dabizha (1980). Palinological data. Deep drillihg shows that the crater funnel is filled опlу Ьу Ноlосепе sediments which are characterized Ьу nearly modern роНеп species (Volkova, 1990). These sediments in the center of tlle crater асе represented Ьу lacustrine clays and 10ams interlaying with loess-like 10ams which fill а small deep ( - 55 т) pit left at the impact funnel just after the explosion. Sиrrounding this pit, опе comes ироп опlу loess-like 10ат layer of 14-25 т thick аЬоуе the allogenic breccia (Izokh, 1990). The same loess cover (usually 05-1 т thick) is widespread in the vicinity and far out from the crater, covering practically the entire Aral Sea region. Stratigraphical data, The 10ess-like cover lies in the tJppermost portion of the regional stratigraphic sequence (excluding the soil) and is unanimously considered as Ноlосепе formation. Its 10cation at the иррес level of the 3-5- high river terraces (but not оп the modern flood-plain level) is а good confirmation of the Ноlосепе age, as well. The regional disconformity between loess-like cover and. the underlying beds (including late Pleistocene) indicates the sharp boundary between' the Pleistocene and the Holocene ( - 0.01 т.у. age). The 10wer limit of the crater's' stratigraphical age is less definite, as the Holocene 10ams mostly lie оп the top of Paleogene and, supposedly, Pliocene sediments (Volkova, 1990). It is опlу at а significant distance from the crater, оп the 35 т - high tепасеs of the Irghiz and Tиrgai rivers, that 10ess-like 10ams cover Фе late-Pleistocene river sands and gravels.

16 Anomaly layer. Just at the base of the loess-like cover E.Izokh (1990, 1991) discovered the geochemically anomalous layer, enriched in Ir, Ni, Со, Cr, Мп, Cd, Zn, Си, РЬ, Лu, F, etc. Due to Mn-enrichment (but not enrichment of Fe-oxides) this layer is usually (but not always) .well recognized in the field. Within the crater funnel this layer 10cated just аЬоуе the allogenic breccia. It was traced in the sequences of the satellite craterlets near the vicinity of the crater, and at great distance from the crater (Izokh, 1991). Within the crater funnel and in the aj acent area the layer is enriched in coarse-grained material, including the chock metamorphosed quartz with planar features, as noted Ьу D.Badjukov (personal сотт:). Лs distance from the crater incl�ases (>5-10 km from the crater rim) the coarse grain material gradual1y diminishes. . ТаЫе 6 Iridium content in the anomalous layer Crom vicinity оС the Zhamanshin crater

Locality, Sediments Depth from Analysed *) sequence# surface Ьу:

9 km Е of the . 1�ss,Q4 0.4 12/11 0.021 F.T.Kyte, crater near 0.5 12/10 0.049 California paved road " 0.6 12/9 0.037 University, (# 33) anomaly 0.7 12/8 029 USA, layer wlth gravel: { clay,sand Р 0.73 12/7 0.042 NAA-method 0.75 12/6 0.052 0.8 12/5 0.069 0.9 12/4 0.024

11 km Е ofthe soil. 0.05 10/1 R.Melnikova crater,along l�ss, Q4 0.1 10/2 Inst.of the same road 02 10/3 Geolow, (# 55) - - 03 10/4 NovoSlbirsk anomal6us layer: { 0.4 10/5 0.62 NAA-method sa�dy clay,P 0.61 10/6 - 0.8 10/7 021 " 1.0 10/8 " 12 10/9 " 1.5 10/10 0.13

*)Sequence # see in (Izokh, 1991; fig. 6а,Ь).

V.Volkoya· (1990) noted another interesting рЬепотепоп. She found that in the anomaly layer near the crater tbere were mainly deformed and

17 smoothed роНеп grains'which look as if partiaHy melted ог burned, while at а distance > 5-10 km from the crater the pollens gradually Ьесоте тоге intact. The heat and steppe Пге caused Ьу the impact event аге the most ргоЬаЫе cause of this phenomenon.

ТаЫе 7 Iridium content in the anomaly layer from Kazakhstan and from the tektite- bearing horizon in Vietnam

Sp.# Locality,sediments De th from Ir (ррЬ) surF: асе (т)

55 11 km Е of crater, 10ess 0.4-05 4.7 75 14 km NE 10ess 05 5.4 83 230 km NE пеаг Turgai village,loess 0.8 8.08

tk2 18 km N of Saigon city, 1aterite 1.0 1.99 under the tektite 1ауег tk7 the same lace 10ess. 0.8-1.0 5.3б tk10/2 45 km N � of Saigon city, 10ess. 1.0 9.17 tk25 10 km N� of Nam Dan village,the same 05 8.18 tk2БЬ 05 8.82 tk29c between Hai Phong and Hong Gai 1.0 5.20 cities, 10ess. tk3б 4 km NW of Son Tai village, 10ess 05 { 9.18 7.75 tk37 7 km S of Son Tai village, 10ess 1.0 95�

. . Ana1ysed Ьу R.D.Me1nikova. NAA-method. For the geo10gica1 sequences, see Izokli and Le Duc Ап (1988); Izokh, (1990, 1991).

Thus, we сап assume а c10se connection between the Zhamanshin crater шd the апота1у 1ауег, 10cated as it is оп the P1eistocene/Ho10cene lisconformity р1апе. The апота1у 1ауег .has Ьееп traced more than 200 km to .he NW and to the W, and тоге than 1000 km to the SE of the crater (lzokh, 1991). Могеоуег, the enrichment in Ir concentration was a1so estabIished in the Vietnam tektite-bearing 1ауег (Izokh, Me1nikova, 1990) (tabIe 7). Therefore, the genetic re1ation between the geochemica1 апота1у and formation of the AATSF, as ап integra1 unit, but not Ьу а single Zhamanshin impact event, seems the most ргоЬаЫе assumption. The pre1iminary suggestion of ап Ir-anoma1y оп the P1eistocene/Ho10cene boundary ОП Izokh, 1991; fig. БЬ) was confirmed recent1y Ьу F.кytе, who ana1ysed samp1es from another anomaly l'lyersequence пеаг Zhamanshin (ор. cit., fig. ба) (tabIe б). Могеоуег, а few separate samples which were taken as opportunity

18 offered in Kazakhstan and in Vietnam demonstrate higher iridium concentration (tabIe 7). These preliminary data allow us to suspect а new cosmogenic Ir-anoma!y оп the P!eistocene/Ho!ocene boundary, which needs further thorough examination.

Chemical Composition of the Zhamanshin Glasses and Target Rocks

The obvious independence of tektites from target rock in chemica! composition was demonstrated before Ьу using - 400 bulk chemical analyses (Izokh, 1986, 1991). Now we have at oиr disposa! тоге than 150 additiona! analyses from the V.Masaitis collection, and -140 from the literatиre. Thus, new chemical featиres have Ьееп disclosed, and the statistics have Ьесоте тоге геliаЫе. Detailed discussion of the Zhamanshin chemistry is ап appropriate subject for another рарег. Nevertheless, the main featиres which help to interpret the tektite age-paradox might Ье considered. The three main groups of me!ted g!ass which were described Ьу Florensky and' Dabizha (1980) need only few terminologica! improvements. Basic zhamanshinites we саll as impactites; the acid zhamanshinites will Ье named MN-type-zhamanshinites. "Basic sprays" of P.Florensky we exclude from the irghizite group. We will discuss below mainly melted glass, but not the diaplectites (impactites of the first type in the termino!ogy of V.Masaitis), which аге widespread in the allogenic breccia debris. The diaplectites аге completely amorphized target ro.cks (si!urian metabasa!ts, porfiroids and s!ates, carboniferous andesites and tuffs, vein quartz, etc.), with initia! structure тоге or less preserved and with chemical composition practically unchanged. For this reason, аll diaplectites are plotted together with target rocks in figures 6-11. Melted impactites form а few separate beds, but mostly they аге found as bombs ог their fragments. The small basic drops like lapilli аге гаге, while basic microspherules of microtektite dimensions аге unknown. The chemical composition of impactites is identical to that of C1-volcanics which were essential1y homogenized Ьу impact melting (fig. 6, 7). Опе must note that central position of the me!ted impactites within the compositional fie!ds of suevites ог target rocks (plotted оп diagrams) is typical of impact craters. R.Grieve (1988, р.163) definitely writes that "Impact melt deposits аге characterized Ьу а high degree of compositional homogeneity. They , correspond to а mixture of the target rocks, еуеп when occиring in volumes of

19 1 2 3 MgO, % м 0,10 Mettea i,mpactLte_s MN""'"Zhaтanshinites lrghizit es Microtektites 8 n=8S n=133 n= 181 n=69 7

O�--�--�--� �=;==��==� 75 8060 50 55 60 85 50 55 80 65 70 7б 80 8б 70 2 3 AZaO /'/0 1 ЗS Melt ed Irghi.z'-tes MicrotektL tes i.mpactites MN- Zhamanshinites n= 181 n=85 30 n=-133 n=89

2б

5 !---т---т----.---....,....--' ...--т-- -т----т-----т--,----,г-----i L.....т-----т----4 Lr----т--,-___г-- -г-' 65 70 8080 65 45 50 5б 60 65 БО б5 60 75 80 8б 70 75 70 75 80 1 2 3 4 FeO,% FeO, 0;0 • Microtektites Меиеа i.mpactites MN- Irghiz'-tes .. 72 Zhal77anshi.nites 1;J3 n=8б n= 1 1 n= 8 n=6Э 11 • Ingh'z'- , • te$ 10

8 7

2�r--.--,--� г--r--г--.--,---т--�-� 55 50 80 8550 55 80 85 70 75 80 85 70 7б 80 85 70 75 80

1 2 3 4 СаО,% СаО,%

Irghizl.te$ Micf'otektites 11

0 1 n=133 n= 181 n=69 n= 85

3 2

1 O г-___ г-___�� ::�� 45 50 55 � �r-� r.---,--.-__� __ � $,02,"0 85 70 75 80 --+ Si 02' СУО Fig. 6a-d. Zh a�anshin . impact crater: . t сот Ь a rams of he rnelte d lmpactites, MN-tektit 1z��o�J�� :kd ! g M( g A 1 РеО, <;аО) - Si02 О, 2�3, es, ir h t1t g es (see ta b es1 6-16ш AppendlX). 1 MgO, ;0 Target,P Torget,Pz 7

1 0 L-�--� 2 1

о 45��--�---r--.---г--.---r�IГ--�� 50 55 80 85 70 75 80 8б 90 95 100 во 65 70 75 80 85 1 2

14 т а r 9 еt: Р,Q.,

70 9 8

;f 2

7 О 40 45 70 75 80 85 90 9б 100 85 70 75 80 85 90 95 1 2 СаО, 11 0;0 Torfjet,Pz 10

9 �--- � ----- 8

4S 50 б5 во 65 ·70 75 80 85 90 95 10060 65 70 75 ВО 85 90 9S $i02,io � � $i02,CYo Fig. Zhamanshin impact crater: comparison Harker 7a-d. Ьу �iagrams(MgO, А1 0 , FeO, СаО) - Si02 0f the target rocks, melted impactites and tektites. Compositional - 2 з fields: 1 metabasalts (greenstones), S - porphyroids, S (6); - quartzite-slates, S (47); 4 - andesites and tuffs, (46); clays, �12); 2 3 С1 5 - loams, sands, �(38); 6 - loess, О (74); 7 - melted impactites - 4. MN-�ektites-zhama�shinites analyses ш brackets. See (133); 8 (1.81); 9 - irghizites (69). Number of analyses of the Zhаmапshш target rocks шАррепd1Х, tables 17-22. hundreds of сиЫс ki1ometers" (Grieve and Floran, 1978). In the Zhamanshin case, however, the melting агеа was limited mostly Ьу relatively smaH vblume of the carboniferous volcanics. The presence of аН of the trarisitional stages from initial carboniferous andesites and tuffs to diaplectites, to slags and. pumices, to glass bombs fuH of parent rock inclusions and, at last, to compact glass bombs is the strongest argument for the basic glass origin most!y (ог exclusively) from the С1- volcanics. It is significant to note that Silurian target rocks (gr�enstones, quartzite-slates, porfiroids) have only diaplectite апаlоguеs.тhis indicates that the si1urian material underwent only shock metamorphism and not impact melting. Muong Nong-type tektites-zhаmапShiпitеs. аге represented Ьу bombs of various size (ир to 05 m in diameter) and Ьу the fragments ог chunks of larger bodies. Individual beds (such as those of impactites) аге not found. Their compositional field оп the petrochemical diagrams does not coincide with that of impactites (fig. 6, 7). There аге по transitional forms ог other ties between impactites апо tektites. The MN-tektite series is strikingly long (from - 50% to - 85% Si02)' This is surely the longest tektite series recorded. Its 10w-sШса part (50-62% Si02) consists mainly of dark sJightly .violet pumice, visuaHy resembling black impactite pumice. The middle part of the MN-tektite series (63-70% Si02) consists of yellow pumice and glass, usually interlaced with dark, low-silica pumice ог with high-silica black glass . .тhе acid part of the series is composed of black glass, often with lenses· ог layers of dense whitish pumice. The well-ordered compositional trends оп the diagrams, and the coexistance of two ос еуеп аН three compositional types of glass within опе chunk аге the best arguments for the genetic unity between аll members of the MN-tet:tite series. e Оп the basis of th MgO content. (fig. 6а) two distinct subseries сап Ье distinguished: LMg and HMg. AdditionaHy, another group сап Ье suspected, resembIing that of уегу high-Mg irghizite series. The MN-tektite series сап Ье опе subdivided into тоге detailed groups using differerit FeO, Са О, К20, etc. compositional trends (fig. 6, 7). With the use of cluster analyses and inner correlation data of various components it is possible to isolate several distinct tektite families, but that is а subject for another рарег. As ап example, the Ыие acid zhamanshinite with Jiquid immiscibility effects (Koeberl, 1988; Zolensky, Koeberl, 1981) should Ье mentioned as опе of visually distinct type of glass. Ii belong: to '1егу Н-Са, H-Mg and L-AI, L-Fe family (fig. 6). Clayish quartzite-slates were proposed Ьу Masaitis and Selivanovskaya

20 (1987) as а compositional equivalents to the acid zhamanshinites. Paleogene clays and sands were proposed Ьу V.Bouska et аl (1981), whereas V.Feldman (1990) offers loess-like loams. However, this latter suggestion сап Ье dismissed from the start, since these loams clearly accumulated after the impact. Mixture of the Paleogene clays, loams and sands (fig. 7, 8) do offer ап acceptable candidate for the acid part of the MN-series. However, for аIl of the sedimentary rocks there exists а negati�e correlation between Si02 and К2О, which is to Ье expected for mechanical mixtures of quartz and feldspar or clay. The tektite series, in contrast to sediments, show positive correlation between Si02 and К20 ос Na20, and this feature is seen only in wеll-фffеrепtiаtеd magmatic series (fig. 8). This feature сап Ье exploited as а sound indication of а nonsedimentary source for the tektites. Indeed, the total absence of target rock analogues fo!' the low-silica part of the MN-tektite series which bears ап unusuaIly high Аl20з concentration (25-34% · а! 50-60% Si02) is the most impressive feature of the Zhamanshin crater (fig. 7). The source material in this case must have had the composition of some уесу specific (exotic) terrestrial rocks, for instance, either low-Fe boxites, ос metasomatic secondary quartzites (diasporites) , ос some metamorphic rocks rich in garnet, sillimanite, corundum, etc., which асе unknown in the Zhamanshin асеа. Мосе than that, it is hardly possible in principle to find them in association with volcanic sedimentary Palaeozoic formations. Thus, the MN-tektite series of the Zhamanshin crater appears out of place in its geological environment. Tektites-irghisites are small « 1-2 ст) glass drops, mainly of comp1icated twisted shape with numerous smal1 « 1 тт) glass spherules agglutinated to the surface (Flor�nsky, 1975). When separated, these smaIl spherules might Ье aptly labeled microtektites or microirghizites. Relative to MN-zhamahshinites, irghizites are richer in MgO, and also sometimes in FeO; they асе роосес in А120з and К20 (fig. 8). However, irghizite-like glass drops compositionaIly identical to MN-zhamanshinites were also found: Irghizites сап also Ье divided into separate fami1ies, using MgO, FeO, СаО, etc. trends (fig. 6). MN-zhamanshinites and irghizites belong to aj arent tektite fami1ies with obvious strong genetic ties, whereas compositional equivalents for irghizites and microtektites remain unknown among Zhamanshin target rocks, despite special attempts to find them. The previously imagined mixture of target sedimentary rocks and stone-meteorite materials, which were evaporated and condensed together (Florensky, Dabizha, 1980; Masaitis, 1989) has по independent ptoof and appears to Ье ап adhoc assumption.

21 f 2 J

.q '1 �J� j

N ,� .... N cO

50 - - St�/ � Si 021 % .... - - Fig. 8. Zhamanshin impactcrater: comparison Ьу Harker diagrams К2О -SЮ.2 of the MN tektites zhamanshinites, basement porphyroids and quartzite-slates, and platform соуес sediments. Composffionaltтe lds: 1 - quartzite-slates, S (47); 2-- porphyroids, S (6); 3 - clays, *'; 4 - loams, *'; 5 - sands, *'; 6 - loess, Q (74); 7 - MN-zhamanshinites (181); 8 - irghizites (69); 9 - melted impactites (133). Number of analyses ih brackets (see Appendix).4 Microtektites represent an integra! part of the irghizite family and, like them, сап Ье subdivided into separate c!usters ог groups (fig. 6), first noted Ьу B.G!ass et а! (1983). They аге arranged in !onger series comparative to the irghizite series, and have the varieties with the highest MgO content. The extrapo!ation of the observed trends further to the !owcSi direction allows us to expect microtektites even richer in MgO, possibly similar to bottle-green microtektites found in sea-bottom sediments (G!ass, 1990). . In sum, the two main typ es о! melted gla.5s present at Zhamanshin аге principally dijferent in origin: basic impactites with - 0. 01 т.у. age origina/ed fr om /he Carbonijerous target volcanics, wherea.5 /he /ektites (acid zhamanshinites, irghizites and micro/ektites) with various (0. 7-5.2 т.у.) ages аге strangers /0 the geological environmen/. Тhey evidently fe ll "from the sky" а.5 а partо! /ektite-bearing projectile.

Comparison of the Zhamanshin апд Austra!asian Tektite Chemistry

305 bu!k chemica! ana!yses of the Zhamanshin tektites, a.ld > 450 tektites from the ААTSF were used to p!ot Harker diagramms. Approximate!y 300 ana!yses were taken from the literature (Baker, 1959; Barnes, 1964; Веуег, 1934; Chapman and Scheiber, 1969; Fudali et а!, 1991; G!ass and КоеЬег!, 1989; Кing and КоеЬег!, 1991; КоеЬег!, 1992; Mason, 1979; Тау!ог, 1962; Тау!ог and Sachs, 1964; Тау!ог and McLennan, 1979; Schnetz!er and Pinson, 1963; Van Potter et а!, 1981; Weinke and КоеЬег!, 1984; Yagi et а!, 1982). Моге than 130 unpublished ana!yses of Vietnamese tektites (fгom E.lzokh and Le Dyc An collection) were a!so p!otted. Ehman et а! (1977) and Тау!ог and McLennan (1979) first noted the compositiona! similarities between Java tektites and acid Zhamanshin g!asses. In this context the Zhamanshin was regarded as а possible candidate for the !ong awaited source-crater for ААTSF, in view of the radiogenic age resemblance and distribution a!ong the !ength of the AATSF (fig. 9). The striking simi!arities between !ayered acid zhamanshinites and MN-tektites from Vietnam were first underscored Ьу E.lzokh (1984, 1986). These similarites were independently confirmed Ьу C.Koeberl (1986, 1988, 1990). As fig. 10 shows, HMg acid zhamanshinites c!ose!y coincide with HMg MN-tektites fгom Indochina and with HMg shaped tektites (S-tektites) fгom South Vietnam and Australia. Numerous scientists (Ehmann et а1, 1977; Frederikson et al, 1977; Taylor and McLennan, 1979; Van Potter, 1981) have noted that the chemica1

23 composition of irghizites most closely resembles .that of Java tektites and billitonites. Beside this, HMg-tеktitеs from Australia and the Philippine have the same close similarity (fig. 10). Figures 6 and 10 demonstrate the distinct compositional clustering of the AATSF-tektites, а well known feature fust estabIished Ьу Chapman and Sheiber (1969) .

• . . . : .. \.... '" """""'------�/

Fi}:. 9. Location тар showing Australasian tektite strewn field (АЛTSF) relative to possible Zharnanshin and Carnbodian source regions. The great circle frorn Zharnanshin through Carnbodia to Adelaide becornes straight line approximately . parallel (о 320-3300 trend line of australite distribution (Taylor and McLennan, 1979, fig. 2). 1 - Zharnanshin irnpact crater, 2 - suggested Carnbodian source region, 3 - rnicrotektite strewn field, 4 - bottle-green (Cpx-bearing) spherule strewn field; 34 - frorn (Glass, 1990).

Вlack-yellow layered acid glass is /.ypical for Zhamanshin, but up today was unknown in апу other part of the АА TSF. Оп гаге ocasior_s slightly similar bIack MN-tektites with yellow lenses were found Ьу Le Duc Ап and the author пеаг Nam Dan village in Central Vietnam. In 1991 E.Izokh chanced to find in the Smithsonian Museum tektite collection (Washington) ап apparently identical bIack-уеllоw MN-tektite fгom Thailand. Specimens, kindly presented

24 а 3 МЛI - telrfttes, In ciослini - AustraZt:tes .!Q VClI7I.teS' 7 Pl7 iliPtoites - 7 tes N Cllltts 171. 17=28 Ill doc!;il7(] И;еtll(l1lJ 17=/41 8 11 = 98 17=37 n=d7 б 5 Ir;lJizi S � t"s 9 3 i J 2 2 1 1

75' 50 ,15 70 75 80 70 75 0'5 70 75 dO

---!-- Si02J% - ь ,)i�, % Аг20",% 1 2 J s Аг2о.»% .1Q val7it.es MN -telrfites) !l7 dОСлil7itеs AuSfra lites Pl7iZLp,01,- 17=141 tJites 17=28 /l7dochLl1a 17 =/3'2 17=37 25

20 15

10 ��II.1 /�

I---,..---т--� ....,.-...,..-----т---,----т---i t---т--т--f �.z...... ;"";;;";"';"";;"";:;'-.---I 5 5 80 115 70 75 dO 85 70 75 80 t55 70 75 dO 70 75 ;:e �% с 11 MN -tе/( titеsJ .:t, 10 In dochil7o ) n'=g8 9 tI 7

О 5 5 • 4 4 3 ,3 �---r---,----т------,--1 t-----.----т---'L..,r-----т----т---I 2 75 2 В5 05 7{} 75 8{} 80 05 70 75 &0 70 75 0'5 10 80 55 70 75 "О 2 5 Са4 % Сао. % 1 tI 3 А Jtl vani tes /ndоСI7t'лifе.r ustrt1lites ) 7 17=14/ 17 =/32 17=28 5

4 . ... J

2 ; J �---т--...,..-� t tJ � �--� �-�-r-��-г  70 6'5 70 75 75 70 75 t5{} 55 15 80 85 70 15 !{} 80 70 55 -----i__ St:O2) %

Fig. 10. Comparison Ьу Harker diagrams (МgО,А12Оз ,FeO,CaO) - Si02 of the tektites froт different parts of AATSF with the Zhamanshin tektites. In fig. lОа-2: 1 - South Vietnam tektites, 2 - North Vietnam tektites, belonging to different bands. A�alises plotted оп diagraтs taken froт: Taylor and М�Lennan (197�); BouSka , et al. (1979); Florensky and Dablzha (1980); Glass at al. (1983'), and from the tables 1-4, ш the Appendv(. Ьу R.Clarke, B.Mason and BEudali, were analysed and turned out to Ье identical to the black-уеВоw zhamanshinites not only visuaBy, but in chemical composition (fig. 11) and in radiogenic age, as weB (see below).

§ s 4 J 2 1 О �-.---т�-.---т��+---.--.�--r--.��--т---� 55 70 75 55 70 15 70 75 7(J 7S 10 15 155 70 15 $iO;/ 1. - ----t.�$i�,� Fig. 11. Comparison of the black-yellow MN-tektite from Тhailand (microprobe analyses) with Zhamanshin MN-tektites compositional field given оп fig. 6. See tables 4-5 in the Appendix.

ТЬе c!ose similaritites between Australasian and Zhamanshin tektites cannt Ье considered now as purely accidenta!, пог сап the origins of these g!asses Ье explained Ьу the melting of identical source material. In this respect, view оп the origin of НепЬигу impact glass, which "has, Ьу сЬапсе, а composition identica! for most e!ements, to australites" and "to subgraywacke" (faylor, 1966) require revision. Bearing Zhamanshin in mind,Henbury glass cou!d Ье part of the tektite-bearing projectile, partly ог completely remelted during the impact. As ап additional argument we also note the comparatively young age of Henbury impact t:rater, ап age close to that of the AA-tektite faB.

Comparison оС Radiogenic Ages оС the Zhamanshin and the Australasian Tektites ТаЫе 8 and fig. 12 summarize data оп тоге than 180 radiogenic ages of AATSF-tektites (а11 published before). ТЬеу demonstrate that fission track age mostly varies between 0.6-0.8 т.у. This is the basis for the widespread ppinion that the age of AAТSF is nearly 0.7 т.у. As а matter of fact, however, tektites of quite different ages Ьауе Ьееп found within the AAТSF. For instance, D.Storzer and G.Wagner (1980) obtained, after а11 needed corrections,fission track ages for certain australites and indochinites differЬу - 0.13 т.у. B.G!ass

25 n = ч.9 I 1 Х -А,. I О 2 5 • J � � о Ч

о 1,5, 1,0 , 1,7,+ 1,� 3,0,' 'f,o, I. 5,0" 10,0т--т- 10о q� т.!! t: 10 0,'1 0,'2 �3 d* d5 �6 fl ssi.On · tracks n=135

� 5, Н

9 1., i I I I I • О 111 111 11111 ..1 11l' _,."- ,.,• ., .-,,,-gI 1 , el\' iili lll� � 5 1,0 1,7 1,8 3,0 *,0 5,0 to,О 11,0 т.!/

. Fig. 12. Summary of the radiogenic datin� of the Zhamanshin and ААTSF tektites (tables 2 and 8). 1·2: АА TSF; 3-5: Zhamanshin; 1,3: fission track data with known аппеаlшg correction; 2,4: fission·track data withput noted corrections; 5 . disputable data of the Zhamanshin basic impactites (see table 1). 6 - fission· . track age of the basic Zhhamanshinites-impactites (our data). (1986) did caJ1 these data into doubt, citing tl1e fact that he had located not two, but only опе microtektite layer in the sea-bottom sediments near AATSF. However, as the genetic Iink between land tektites and sea-bottom microtektites is disputed (see below), B.Glass arguments seem to Ье incorrect. ТаЫе 8 Radiogenic ages оС the tektites from the Australasian strewn field

N # Specimen Method Age, т.у. References 1 2 3 4

1 Australites (6 sp) K-Ar 0.72±О.06 Zahringer, 1963 (O'Keefe, 1976) 2 Indochinites(3 sp) 0.73±О.6 3 Philippinites (5 sp) 0.70±О.07 4 Thailand, Вorneo 0.72:tO.06 е.о. (4 sp) Аа Fission e 5 ustrali te <0.03 Fleis her and· track Price 1964 6 " О.l1±О.04 7 " O.l3±O.02 8 " 0.34.±О.01 9 " 0.66.±О.0 1 10 " 0.64.±Q.l6 11 -"-(core) 0.69±О.05 12 - " - (f1ange) 0.69±0.о7 13 Australite 0.80:t02 14 Darwin glass 0.65:tO.l •• 15 Australite (660-1) 0.66:tO.02 Gentner et al, · 1969 16 Australite (660-2) 17 Australite (660-3) �i�;g:��••: 7 о. 1 :tO.l4. 18 Australite (660-4) 0.54 :tO.02 •• 19 Australite (660-5) ��;g:�. 0.66±О.14 . 20Australite (660-6, 0.34±О.03:•• core) 0.70:tO.l4• 21 Australite (f1ange) 0.13:tO.02 · 0.74 ±O.l4 22 Australite (660-7, 0.40:tO.05 :•• core-l) 0.74:tO.l4• 23 Australite (core-2) Fissiоп 0.63 :tO.04•• Track 0.72 ±O.l4

27 ТаЫе 8 (contin.) 1 2 3 4 . 24 Australite (flange) Fission О.48;±О.06•• Gentner et al, track О.71;±О.14 1969 " . " 25 Аustrali te (660-8, - - 031 ±Q.04•• - - core) 0.71;±O.l4 " . 11 .' 26 Australite (flange) - - - 033±Q.03 · O.68;±O.l 27 Australite (660-9, - " - 0.71±Q.04< - " - core) " " 28 Australite (flange) - - О.70±Ш� - - 29 Australite (133) - " - 0.68±Q.1 Wagner, 1966 (Gentner et al, 1969) " " · - 30Australite (134) - - 0.63±Q.l •• - 0.73±Q.l4 " . 31 Australite (131) - - Gentner et al, 1969 32 Muong Nong tektite - " - 0.68±Q.04g� �:��.:. - " - (572-1) 33 - " - (572-2) - " - 0.72±Q.04 - " - " " 34- " - (597-1) - - 0.61 ±Q.04: - - " . " 35 - " - (597-2) - - 0.67;±О.04 - - " . " 36 - " - (597-3) - - 0.65±Q.04 - - . " 37 - " - (58) - " - 0.64 ±Q.04 - - " . " 38 - - (Kemray) - " - 0.67;±О.04 - - " 39 Darwinglass - " - 0.69,{).74� .04 - - (ave. of 6 sp) 0.72±Q.04 40 Philippinite (GA1514) K-Ar 0.70'{).84 McDougal and (ауе. of 10) (0.78;±О.05) Lovering, 1969 " " 41 Philippinite (GAl992, - - 0.78-1.41 ±Q.o2 - - ауе. of 14) O.96;±O.l 42 Philippinite (GAl992) - " - 4.50;±O.l - " - 43 Australite (GA2054) K-Ar 0.83.{).91±Q.02 core (ауе. of 7) 0.88±О.03

" " 44Australite (GA2349) - - 0.73-О.86±о.о2 - - core (ауе. of 2) ·0.79 ±Q.09 " " 45 Australite (GA2064) - - 0.79,{).93±Q.02 - - core (ауе. of 5) 0.86 ±Q.07 " 46 Astralite (GA2055) - " - 0.81-1.13±Q.02 - - core (ауе. of 5) 0.

28 ТаЫе 8 (contin.) 1 2 3 4

49 Australite (аА235О) K-Ar 0.92-1.01 ±О.03 ·McDougal and core (ауе. of 3) 0.95 ±О.05 Lovering,1969 50 Australite(аА2065) 0.77-1.00±О.02 " core (ауе. of 6) О.87±О.О9 51 Same sp� flange, 0.85-1.02 ±О.03 (аА2066),ауе. of 4 0.94±О.12 52 Australite (аА2067) 0.7�.80±О.О2 core (ауе. of 4) 0.75±О-07 53 Same sp. (аА2068) 0.99-1.11 ±О.03 flange (ауе. of 4) 1.05±О.ОЗ 54Australite (аА1995) 0.85.Q.97±О.03 core (ауе. of 4) 0.91 ±О.09 55 Same sp. аА1996), 1.16+М4 flange 56 АustлiJitе (аА1997) 0:79-1.09 ;tO.02 core (ауе. of 4) . Q.94±021 57 Same sp� flange 1.79±О.04 58 Australite (аА1993) 1.11±О.03 compositeflange 59 Australite (аА2089) 0.86-1.19 ±о.02 core 60Same sp. (аА2091), K-Ar 1.19±О.02 McDougal and front part Lovering, 1969 61 Same sp. (GA2090), 1.12±О.03 " flange 62 Australite (аА2057) 0.70-1.02;tO.02 соте (ave.of 10) 0.85±O.l1 63 Same sp. (аА2056), 1.О9±О.03 .flange ' 64 Philippinite Fission 0.6З±О.06 Fleischer et al, 1969 1 track 65 -"- 0.78±О.08 66Muong Nong tektite, 0.78±О.08 Тhailand 67 - " - 0.45±О.05 68 Darwinglass 037±О.04 69 -"- 0.75±О.08 70 -"- 0.66±О.07 71 -"- 0.76;tO.08 72 -"- 0.59;tO.06 73 -"- 0.68 ±О.07 74 -"- 0.69+0.07 О.60±о.06 75 Macedon glass ' 76 -"- 0.59±О.06 Fleischer et al, 1969 2

29 ТаЫе 8 (сопtin.) 2 3 4

77 HNa-аustrаlitе Fission 425 0.43 F1eischer et al, track + . (AN87) 4:65±о.50 196?, 2 78 - " - (AN245) 3.10+0.30 79 -'� - (AN370) 3.54±о35 80Average australite J<-Ar 0.72±О.06 O'Keefe, 1976 81 - " - Fission 0.70±О.1 track 82 Average indoshinite K-Ar 0.73±О.06 83Average philippinite K-Ar 0.70±Q.07 84 Average javanite K-Ar О.72±О.О6 85 Average Darwin glass Fission 0.72±О.1 track 86 Average Muong Nong 0.71 ±Q.1 tektites 87 Average microtektites O.71±QJ 88 Average Australasian 0.1 �.7 ' •• Storzer and Wagner, tektites 0.70±Q.07. 1979 89 Australite (А-1) 0.75 ±Q.12 •• Storzer and Wagner, 0.845 ±Q.0f6 1980 90 _.- (А -l1) 0.73±О.06 •• . 0.821 ±O.0i5 91 lndochinite(JA-2) О.66±О.О8 •• 0.692 ±Q.Oi5 92 - " - (JA-3) 0.73;tO.08 •• 0.69610. 013 93 Philippinite (18) 0.7110.08 •• 0.691;1;0·064 94Javanite 0.67 •• Nishirnura, 1981 95 MN-tektite 0.651РО У agi et al, 1982 96 Javanite 0.71 •• Watanabeet al, 1985 97 HNa-аustrаlitе 11.0 Storzerand . . Mliller-Sohnius,1986 (after Koeberl, 1988) 98 Australite 0.6410.11:. Virk, 1985 О.83±О.11. 99 .11. 0.75.±Q.09•• . 0.95±О.09. 100 -"- 02610.04•• 032±Q.04 • 101 Darwin glasS 02410.06•• 034±О.06 102 Indochinite Fission 0.11 10.03:. track 022±О.03

30 ТаЫе 8 (contin.) 1 2 3 4

103 Philippinite Fission 0.72;tO.ll:0 Virk, 1985 track 0.82 ;tO.11 • 104 Indochinite, Dalat K-Ar О.86±О.08 Shukoljukov and (1-4) Javnel, 1986 (Elzokh's specimens) " " 105 - " -,Оиу Нор - - 0.86±Q.08 - - (7-6) " " - " 106 - -, Нат Уеп . - O.76;tO.08 - - 7) (24- " 107 - " -, Уеп Bai - " - 0.79;tO.08 - - (30-4) " 108 MN-tektite, Danang - " - 0.76;tO.08 - - - (А55 5) " 109 - " - (А65-4) - " - 0.76 ;tO.08 - - " " 110 - " -, Nguyen Dak - - O.86;tO.08 - - Nong (А 79-8) " 111 Indochinite,Phu Tho - " - O.99;tO.08 - - (33-7) 00 112 MN-tektite, Bien Fission 0.44;tO.05 Kashkarov et al, 1986 Ноа (А72-3) track (E.Izokh's specimens)

" 113 Indochinite, Dalat - " - 0.44 ±О.03 - - (1-3а) " " 114 - " -, Kyang - - 0.44 ;tO.05 - - Ngai (А67-3) 115 МN-tektite, Danang - " - 0.45 ;tO.06 - " - (А55-6) " 116 Indochinite,Dalat - - О.46 ±О.О4 - " - (1-3) li7 - " -, Bien Ноа - " - 0.47±О.06 - " - - (А 73 4) " - " - (А75-2) - " - 0.48±О.06 - - 118 " 119 MN-tektite, Kuang Fission 0.50±О.07 - - (А59-5) . track Ngai " 120 Indochinite, Nguen " - 0.51;tO.05 - - -7) Dak Nong (А79 " 121 MN-tektite, Kyang - " - 0.52 ±О.06 - - Ngai (А49-6) 122 Indochinite,Tai - " - О.56±О.О7 - " - Phuong (19-5) " 123 MN-tektite, Danang - - 0.57±О.06 Kashkarov00 et al, (А57-2) 1986

31 ТаЫе 8 (end) 1 2 3 4

- " Fission 124 -, Копшm track О.59±О.06 Kash� y.et al, (А12-3) �� " 125 Indochinite,Pleiku - - О.60±О.О7 - " - (А20-2) " 126 MN-tektite, Danang - - О.60±О.О7 - " - (А4-2) " 127 Indochinite, Vinh, - - О.61±О.О7 - " - Nam Оап (A8i-15) . " " 128 - -, Phu Tho - - О.61 ±О.О8 - - (33-6) " " 129 - " -, Куи Нор - - O.62±Q.06 - - (7-5) " 130 - " -, (8-5) - " - О.62±О.06 - - n " 131 МN-tеktitе,наm Уеп - - О.62±О.О7 - - (24-6) 132 - " -,Тиуеп Quang - " - O.63±Q.07 - " - (29-3) " 133 - " -, Phan Rang - " - O.67±Q.06 - - (А28-2) " " 134 - " -, Nam Dan - - О.67±О.08 - - (А83-1) " 135 Indochinite,Kontum - " - О.68±О.09 - - (А13-2) " 136 MN-tektite, Phan Fission О.69±О.06 - - Thiet (А39-2) track " " 137 lndochinite, Kontum - - O.77±Q.08 - - (А19-2) " " 138 - -, Уеп Bai - - O.79±Q.09 - " - (30-2) " " " 139 - -, Dalat - - O.80±Q.06 - - (А33-2) " .. " 140 - " -, Kyang Ngai - - О.80±О.1 - - (А50-2) " " 141 - " -, Уеп Bai - - O.83±O.l1 - - (30-5а) " " " 142 - -,Nam Dan - - О.!!8±О.О9 - - (А81-15) 143 - " -, Dalat К-Ат О.76±О.12 Arakeljants et al, (1-1) 1988 144 MN-tektite; Danang - " - О.68 ±О.12 (А55-8) • •• Apparent fission �;ack age or по commentaries оп correction; corrected age.

32 Notably, tektites with ages of 354-4.25 tn.y.were found Ьу Fleischer et аl

(1969), whereas Storzer and Muller-Sohnius (1986) reported tektites of - 11 т.у. in Australia. After the fl rst finding of tilOse "old" tektites V.Barnes (1973, Р.195) ironicalIy noted that "these specimens show _the same amount of etching as the younger australites, and why, with the whole wщld as а target, did these tektites соте to rest in а area of similar tektites?" Moreover, the first systematical fission track age investigation of the tektites, collected from а single tektite-bearing stratigraphic layer in Vietnam (Kashkarov et al, 1986) revealed three statistically discrete tektite groups with different ages: 0.4, 0.6 and 0.8 т.у. (table 8). Insomuch as с.коеЬегl (1992, р.1052) has called these data i.nto question, these results are here represented in light of the compari�on between the diameters of spontaneous and induced fission tracks (fig. 13). Thus, we have evidence that the AATSF contains tektites of different ages which apparently fell simultaneously. This assumption does not square with the EIТ, and thus generally ignored-.

Sp AJJ -2 Sp A50-2 Sp AlJ Sp A5.9-5 �60x�Oo t160rq! q4li:q. 450:tq07 N m.у. /77.у. ту. /77.у.

20 '

� 10 f о - �O о 40 О �O

Fig. 13. Examplary histograms: diameter (D) - number (п) of the spontaneous (hachure) and induced fission-tracks in tektites with different a�e from Vietnam. Тhe an:ilealing correction used only to Sp. А 50-2 (Kashkarov et al� 1986). .

33 ТЬе table 8 and fig. 12 demonstrate that K-Ar ages are often (but not always) older comparative to fission track ones. In order to find the explanation of these рЬепотепа, it is essential to remember that -flanges in some button-shaped australites bear systematically older K-Ar ages than the cores of the same specimens do (McDougall and'Lovering, 1969; table 8, 43- 63). ТЬеп, as J.O'Keefe writes (personal letter) "the flange glass will Ьауе extra (parentless) argon, which is so often discussed". J.O'Keefe explains this fact Ьу earth's atmosphere ablation, which "removed something - like half of the. original mass; of this, а major fraction was 10st Ьу vaporization. "As the experimenters insist that argon is retained with great tenacity, in this process potassium was 10st more than argon". Thus, Ье concludes, "the radiogenic dating supports the geo10gical evidence for а wide difference between the date of formation of the tektites some 0.8 т.у ago, and the date of theyr deposition . оп the earth".

However, this traditiona1 арреа1 to _ the earth's atmosphere ablation seems to us invalid, since fission track ages of tlie cores and flanges - of the button-australites are practically equal (Gentner е! а1, 1969; table 8, # 20-28). ln rare cases these tektites suffered оп1у recent periphera1 heating iшd subsequent peripheral fissiontrack annealing wheQ penettated through earth's atmosphere, 1ше that of meteorites (Korotkova et а1, 1987). Тherefore, button shape australites obvious1y fell to Earth fuHy shap'ed and practically intact. Тhus, quite naturally they Ьауе по obvious traces of interaction with the earth's oxygen and water vapors, as well as with the earth's ground materials. То break through the long 1asted controversy we assume that b.utton shape australites underwent some process of extraterrestria1 abIation, Inost. probably the secondary melting of small- vo1canic ЬотЫ slow1y descending opposite to the stream of the eruptive gas jets (Izokh, 1987). Following this idea, the slightly older K-Ar ages of tektites comparative to their fission track ages сап Ье exp1ained Ьу the presence of ап extra argon inherited from older mineral inclusions, such as quartz (1echatelierite), feldspars, etc. These crystalline grains are often ' concentrated . a10ng the stirface- between distinct layers in the MN-tektites (Barnes, 1963, 1973; D.Futrell, persona1 сотin.) and оп the "old". surface of the button-iiustralites covered Ьу secondary melted flanges (Barnes, 1963; СЬао, 1963; Glass, 1970; Delano, 1992). Тhese partially preserved сгуstаШпе inclusions are sometimes composed of coesite, chromite, zircon, etc, which are alien to апу tektite glass. Тherefore, these inclusions could Ье considered' as some kind of "peppering" or precipitation of

34 environmental dust. Of course, ап extraterrestrial mode of origin of these foreign inclusions is а disputable question. However, as G.Baker (1959, р. 86) notes: " ...there is nothing to disprove that they could have Ьееп develo�d ироп some extraterrestrial source". Оп the whole, the compatibility of tektite K-Ar and fission track dating looks тисЬ more satisfactofy than that of impact melted glasses, which are usually тисЬ more contaminated Ьу the old material comparative to tektites. Thus, the nearly equal tektite ages measured Ьу tw

ТаЫе 9

Fission track age of the black-yellow layered МN-tektite fгош Тhailand

Sp. # U Nsp spont� induc. Apparent Corrected f 2 f 2 (ррm) сm .1 ст age,m.y. age,m.y О). .БZ6S" 2.4+{)3 93 570 +60 I (4.8+02)105 058+05 12+02 ">Diameter-correction of annealed spontaneous fission tracks, relatively to induced ones, is -0.48.

ТЬе comparison of the э;gе data given in tables 1 and 9 shows а close age similarity between MN-tektites from Zhamanshin crater and from Thailand. As the impact origin for identical glass with such specific features in distant sites is highly improbable, there remains only one solution: to assume that the Zhamanshin tektites and Thailand tektites fell "from the sky" simultaneously along the ' АЛТSF stripe, i.e. along the same trajectory. ТЬе age-paradox occurence in Australia, Indochina, and in the Zhamanshin crater (Iwkh, 1985, 1987) is the strongest argument for the above assumption, as well.

35 ТЬе Main Results and-Discussion

Age of the Zhamanshin impact event . Approximately -0.01 т.у. age 01 the Zhamanshin impact event was obtained Ьу several iridependent mефоds, which stand in contrast to the earlier view of_ - 0.7�1 m.y.age, а view based exclusively оп the dating of tektite glasses. ТЬе methods used to prove our new statement are as follows: mo;phological (the state of the preservation of the crater's structure); geomorph,ological (ages of the river terraces); str.atigraphic (Holocene position pf the filling sediments and 10ess-like sediments in the vicinity);palynological (Ноlосепе pollens in the post-impact sediments and burned роllеп grains in the anomaly layer); geochemical (апота1у layer, rich in Ir, Ni, Со, Cr, Мп, etc., wbich coincides with the impact event and is 10cated оп the P1eistocene/Ho10cene boundary); paleomagnetic (tlie reverse po1arization of the impactites, characteristica1 0f Heteborg episode of 9-11000 y.�go); - 0.01 m.y.I/Ssion track age for the basic impactites both from -the surface and from the deep bore-ho1es (new data); - 0.01 m.y.f/Ssion track age for the MN-type zhamanshiniie which was remelted at the Оте of impact (new data); and Ппаllу, the thermoluminescence method (independent confirmation of the - 2 order of magnitude difference between the Zhamanshin impactites and tektites). Special experiments permit the elimination of the suggested differences of therma1 stability between basic and acid Zhamanshin glasses (with respect to the fission tracks preservation) as а possible cause of observed age differencies. In· the end, the radiogenic ages of the Zhamanshine tektites proved to Ье far older than those of the irp.pactites(0.7-5.2 т.у. vs - 0.01 т.у.).

Age paradox . Severa1 versions of the tektite age-paradox are visible in the Zhamanshin crater: 1 - the great difference between tektite age of formation and age of 1anding uроп the Earth; � - the same differerice between the radiogenic ages of the impactites and tektites; 3 - similar difference between intact tektitesandtektites melted during the impact event; 4 - the coexistence of tektites with various radiogenic ages which fell obvious1y together. ТЬе age-paradox was first established in Australia, confirmed Ьу E.lzokh and Le Duc Ап (1983, 1986) in Vietnam, and finally noted in the Zhamanshin crater (Kashkarov et а1,. 1988). rhis age-paradox is fata1 to the EIТ, and по wonder there are continued attempts to ignore or - otherwise _ disavow its significance (G1ass, 1978,1986,1990; Koeber1,1986-1992; Masaitis et аl, 1991; etc.).

36 Composition and source оС the Zhamanshin glasses. Sharp differences between impactites and tektites in b.oth age and c.omp.ositi.on pr.ovides the str.ongest argument in fav.or .of their different .origin. ТЬе Zhamanshin impactites represent с.отт.оп type .of melted target r.ocks, resembIing th.ose f.ound in .other impact structures. Their melting area was limited .only t.o the carb.onifer.ous (С1) v.olcanics, while the silurian target r.ocks suffered m.ostly str.ong sh.ock metam.orphism. Unlike melted impactites, Zhamanshin tektites are highly heter.ogene.ous and сап Ье subdivided int.o several c.omp.ositi.onal gr.oups, as it is clearly visibIe .опthe Harker diagrams (fig.6-8). These gr.oups сап Ье named as ev.oluti.onal series and subseries in the language .of igne.ous petr.ol.ogy. Comm.only, these gr.oups are labeled tektite fami1ies, gr.oups, lineages, clusters, etc. MN-type zhamanshinites represent the l.ongest kn.own tektite series (50- 85% Si02) with micr.otektites ranging а sh.orter .опе (60-80% Si02)' Irghizites Ьауе the sh.ortest range (70-80% Si02)' ЕасЬ .of these series сап Ье also subdivided int.o discrete subseries, which differ with respect t.o c.oncentrati.on .of MgO, FeO, СаО, К20, etc., taken separately .ог in c.ombinati.ons. It is imp.ossibIe t.o IQcate апу c.omp.ositi.onal equvalents t.o these tektite series (if we take them as the integral units) am.ong the Zhamanshin target r.ocks. Only а few c.omp.ositi.onal tektite an.ol.ogues сап Ье f.ound Ьу special selecti.on ·.of the appropriate chemical analyses .of s.ome clayish quartzites .ог l.oams, .or alternatively, Ьу the imaginary mixing .of vari.ous sediment layers as it is esp.oused Ьу adherents .of the EIТ (Tayl.or, 1966; Delan.o and Lindsley, 1982; Masaitis and Selivan.ovskaya, 1987; K.oeberl, 1992, etc.). Fr.om the EIТ p.oint .ofview, the Zhamanshin impact event was unique when c.ompared with .other impact f.ormati.ons, because it pr.oduced h.om.ogenized basic melted impactites while simultane.ously generating widely differentiated tektites, which alIegedly .originated Ьу уегу exact impact melting .ofthe selected r.ock layers. Meanwhile, the c.omp.ositi.on .ofLSi-НАI part .of the MN-tektite series cann.ot Ье explained Ьу the EIТ, in principle, because .oft.otal absence .of the equivalent target r.ocks. ТЬе irghizite and microtektite series als.o lack а suitabIe equivalents in the target materials. Nevertheless, the .origin .of irghizites is explained (Ш} hoc) · as а mixture .of mete.orite and target materials, which evap()rated and c.ondensed fr.om ап impact expl.osi.on cl.oud (Fl.orensky and Dabizha, 1980; Masaitis, 1989). H.owever, it has t.o Ье уегу peculiar cl.oud, curi.ously c.ompact and small, considering the dimensi.ons .of the irghizite landing patches. Additi.onally, the suggested mete9rite pr.ojectile s.omeh.owleft п.оtraces in the c.omp.ositi.on.of the basic impactites . Finally, the

37 supposed impact ОГlgш of the irghizites implies (М hoc) the selecttve evaporation of exactIy selected quartzite layers in the close vicinity of meIted basic impactites, while they themselves were not evaporated. The platform соуег sediments, mostly soft and unstable, show по evidence of impact compression and meIting. Thus, they must Ье eliminated as possible tektite source material (Masaitis and Selivanovskaya,1987). Опе must also note the post-impact sedimentation of the loess-like loams. Moreove)', all of the sedimentary rock are,in fact,a mechanical mixture of quartz and feldspar (or clay) components, and hence have negative correlation between SiOZ апд KzO or NaZO. Therefore, theY4f;annot Ье а source material for tektites. All of the аЬоуе listed observational (not deduced!) facts, not to mention the age-paradox, cannot Ье explained Ьу the EIТ without а number of various ad hoc assumptions. It is more logical to assume, that аll of the Zhamarishin tektites were part of the projectile itself, as it was proposed Ьу J.O'Keefe (1987). The secondary impact melting noted in some of. the MN-zhamanshinites confirms this idea. Origin оС the Zhamanshin tektites.The hypothesis of the extraterrestrial volcanic origin for tektites, persistentIy developed Ьу J.O'Keefe, was supported Ьу D.Futrell (1977, 1986, 1991). Now it is strongly confirmed Ьу the data presented in this study. For instance, only ап extraterrestrial volcanic process could produce and accumulate in опе place tektites of differing ages and chemical composition, which were .carried together to the Earth in ап ordered fasblon, in а possible accordance with initial distribution around volcanic centre. The layered MN-tektites сап Ье compared with lava-flows formed over а long period of time (Futrell, 1986). Thus, the discovery of two layers of different age within опе of the MN-zhamanshinites (Deino et al, 1991; see table 1) becomes understandable. Shaped tektites and irghizites, in their turn, сап Ье compared with volcanic bombs and lapilli. The irghizites and microtektites were most ргоЬаЫу produced in ап especially turbulent volcanic eruption, while normal S-tektites were probably the products of quieter explosions. Last, but not least, various tektite compositional famiIies have their analogues in eruptive series, phases, irnpulses, et<;. of а terrestrial volcanoes, though corrections in respect of extraterrestrial conditions are necessary. Considering the age-paradox span (from hundreds of thousands to millions years), we prefer to replace the tektite source volcano оп the Мооп, as proposed Ьу J.O'Keefe, Ьу some тоге distant planet body, however, still unknown (lzokh, Ап, 1983, Izokh, 1987).

38 Comparison of the Zhamanshin and Australasian tektites shows that both have similar if not identical radiogenic age and chemical composition. The EIТ offers two rival hypothesis to explain the distribution of similar tektites within the gigantic ААTSF (-13000 km long) from Tasmania to Indochina and to Zhamanshin crater. The most popular of these hypothesis posited а single source crater somewhere in the Indochina, most likely at the Топlе Sap lake site in Cambodia, where tektites · were supposedly produced from jurassic sediments (Rartung, 1990; Blum et al, 1992; Koeberl, 1992). The second hypothesis suggests multiple impact cratering with supposed "first touch me1ting" of the surface loess (Barnes, 1973; Wasson, 1991). In the second hypothesis, however, "the crater problem has Ьееп multip1ied - instead of опе missing crater, there would Ье а multip\e of missing craters" (Koeberl, 1992, р. 1057). Neither of these hypotheses, however, сап explain the close connection between the Zhamanshin crater and the AATSF. Spatial distribution of tektites of different chemical composition is опе of the most intriguing features of the AATSF. Its discrete (clustered) structure, i.e. tektite distribution in the form of long distinct bands was first established Ьу D.Chapman (1971), and later confirmed in Austra1ia Ьу BJylason (1979, 1990) and in Vietnam Ьу E.lzokh and Le Duc Ап (1983) . . The spatial distribution of tektites оп the surface of the Zhamanshin crater rim also bears clustered character, though the tektites occur only in patches. Since the Zhamanshin structure is surrounded Ьу а host of satellite craterlets, it is logical to assume that it is ап imprint of the landing of the · swarm of disintegrated extraterrestrial body, with possibIe voluminous (not flat) dimensions. This observational fact he\ps to explain the perfect preservation of tektites which supposedly fell in the wake of swarm, i.e. at the end of ап impact explosion, while the tektites, which fell ап instant ear1ier, Ьесате partially ог completely remelted. The idea of tektite delivery Ьу а specific eruptive comet (lzokh. and Ап, 1983; Izokh, 1988) also sheds light оп the evidently soft landing of some tektites, the disappear\lnce of main projecti1e materia\ of the craterlets, and оп the patch-1ike distribution of tektites. The complex Zhamanshin structure could Ье interpreted as the impact of а comet swarm with the relatively steep ог nearly vertical trajectory. The band-1ike structure of the AATSF, in contrast, сап Ье explained Ьу less angular ог skipping trajectory of а comet swarm which produced bands of "tektite showers" and soft tektite landings in certain localities (lzokh, Ап, 1983). Ап occasional direct impacts, producing relatively small craters like Darwin,

39 НепЬигу, Wabar ог Аоиеllоиl craters, сап not Ье ruled out, however. АII of the аЬоуе pattern of the tektite spatial distribution in the АЛ TSF was excellently explained Ьу D.Chapman (1971), who applied ballistics trajectory calculation to the case of landing of ап ordered tektite swarm, supposedly originated Ьу impact оп the Moon� J.Wa.sson's (1991) calculations of comet fragmentation and landing аге also helpful in the understanding of the origin of the АЛTSF. Only опе step forward is needed to further the idea of V.Barnes and J.Wasson; that is, to recognize that the comet swarm did not produce tektites from the Earth's surface, but rather carried them within itself. /n short, this рарегsuggests that the Zhamanshin crater сап Ье considered small modelfor the gigantic М TSF. . as а · Relationship Ьетееп tektites and microtektites. This рroЫет has intrigued scientists for years, and there is to date по satisfactory answer. ТЬе main Zhamanshin data wich helps to solve the ргоЫет аге as follows: 1. Microtektites and irghizites both belong to the same HMg- family. 2. The . both belong to the specific morphological tektite-type, with microspherules agglutinated to highly deformed, twisted glass bodies. 3. Microtektite chemical variations аге wider (60-80% Si02) relative to that of irghizites (70-80% Si02), and thus represent тоге complete and possibIy тоге complicated process of formation. 4. Zhamanshin microtektites,in principle, аге not unlike microtektites found in the sea-bottom sediments. The bottle-green glass spherules typica1 of them аге absent at the Zhamanshin. However, they сап Ье predicted Ьу extrapolating observed chemica1 trends to the 10west sШса агеа (fig. 6). 5. Irghizites and microtektites Ьауе their chemical (but not morphological) equivalents among the MN-tektites-zhamanshinites, as well as among S-tektites from Java, BiIliton, Australia and the Philippines. 6. The irghizite morphologica1 type is not known in other parts of the АЛTSF ог in other tektite strewn fie1ds. Thus, the well known absence of microtektites оп land becomes understandabIe. 7. Darwin glass of the irghizite morpho10gica1 type represents the sing1e exception which a1so proves the rule. 8. Microtektites of the Zhamanshin crater аге excellent1y preserved and have по traces of etching ог corrosion. Nevertheless, the fact of the total absence of microtektites оп the 1and has Ьееп interpreted Ьу proponents о! the EIТ as а result of intense ground corrosion ог demolition during геdеiюsitiоп (G1ass, 1974, 1978; Koeberl, 1988). ТЬе microtektites from the Zhamanshin demonstrate the inconsistencies of these suggestions.

40 9. ТЬе age-paradox forces us to assume rather unusual extraterrestrial conditions for irghizite- and microtektite formation, still not known оп the Earth. Based оп the data presented in this work, опе must assume ап exceptionally turbulent volcanic eruption; with dispersion or pulverization of the boiling melt producing the twisted, agglutinated irghizites and separated microtektites. Оп the other hand, the S-tektites of normal morphological type must Ьауе originated during а less violent volcanic eruptions. ТЬе coincidence between the stratigraphic and radiogeniC" ages of sea bottom microtektites ( - 0.7 т.у.), ajacent to the AAТSF, is almost unanimously recognized. This is the main ' reason cited in rejecting the age paradox (Glass, 1978; Koeberl, 1986, 1992). However, if this coincidence is real, then' microtektite- and 'land tektite strewn fields represent the different tektite systems. ТЬе different spatial orientation of both strewn fields: submeridional for the ААTSF, and lattitudinal for the microtektites, is another confirmation, especially if' the bottle-green microtektites, which stretch across the whole РасШс Осеап, are considered (see fig. 9). However, if ihe extraterrestrial origin of tektites and microtektites is taken as the reality (following the Zhamanshin example), then something wrong сап Ьу supposed with the microtektite sea-layer stratigraphic or radiogenic ages. As а matter of fact, almost аll microtektite concentrations are found аЬоуе the Brunhes/Matuyama boundary, i.e. in the stratigraphic position of 0.06-0.26 т.у younger then the 0.7 т.у age of the reversal boundary (Glass, 1986). C.Burns (1989, р.254) writes: "the stratigraphic relationship betweem the microtektite layer and the reversal boundary is not . . . clear because the microtektites Ьауе Ьееп displased from theyr огigiпаl position Ьу bioturbation, and the reversal boundary has Ьееп affected Ьу the process of postdepositional detrital remanent magnetization". Now we Ьауе а rigt to suggest that the age-paradox still was not recognized in the microtektite case. If our logic is correct, опе would expect to find primarily irghizite-like morphological type of tektites in association with sea-bottom microtektites. However, the problem of belonging australasian tektites and microtektites to опе or two different events remains unsolved.

Summary

ТЬе following new data were presented in this paper: 1. Fission track dating of basic Zhamanshin impact glass �ollected from deep bore holes shows the same -0.01 т.у. age, as that of the day-surface

41 glasses, analysed before. Thus, the possibility of annealing of the impact glasses Ьу the heat of the Sun, fires, etc. is eliminated. 2. Experimental glass heating did not support former contentions that the basic glass is thermally highly unstable relative to acid glass. 3. The Muong Nong-type tektite-zhamanshinite, partially remelted during impact, Ьауе fission track age of - 0.01 т.у., while tektites not remelted (intact) аге тисЬ older (0.7-5.2 rn.y.). 4. Similar significant age differences between basic impactite� and acid tektites were independently confirmed Ьу the thermoluminescence method. 5. Еагliег findings regarding the reverse magnetization of impactites were confirmed. However, they аге interpreted to indicate тоге recent (-0.01 т.у. ago) Heteborg episode of reversed magnetization, but not previously suggested . Matuyama epoch. 6. АН available geological d-ata (stratigraphical, palynological, geomorphological, etc.) were presented and summarized to demonstrate the уегу young age of the Zhamanshin impact event which coincides with the Pleistocene/Holocene boundary - 0.01 т.у. old. 7. Preliminary data оп the geochemical anomaly (Ir, Ni, Со, Сг, Мп, etc.) at the аЬоуе boundary were confirmed Ьу new Ir-analyses completed in University of California Ьу F.Kyte. The simultaneous formation of the anomalous layer and the Zhamanshin impact crater provide additional confirmation of its уегу young age. 8. Insomuch as the radiogenic age of the Zhamanshin tektites is for the most part -1 т.у., the famous tektite age-paradox appears quite well-defined and points to the extraterrestria\ origin of tektites as the most plausibIe. hypothesis. 9. Essentially extended data of the Zhamanshin chemistry al10w us to confirm independent origin for basic iml?actites and the acid tektites. 10. Melted impactites, in general, аге products of the complete melting and homogenization of the target carboniferous (С1) volcanics, while adjacent silurian greenstones, porphyroids and quartzite-slates suffered mainly shock metamorphism. There is по evidences that the sediments of the platform соуег participated in the impact metamorphism and melting. 11: Iп сопtгаst to impactites, Zhamanshin tektites аге not homogenized, but аге represented Ьу different compositional groups: series and subseries (families, clusters, etc.), resembling the products of various volcanic eruptions (phases, impu\ses, etc.), however, working in an extraterrestrial conditions. 12. Comparison of Zhamanshin tektite and 1arget rock chemistry shows

42 that the tektites Ьауе по compositiona! equiva!ents in the target rocks and appear to Ье tota! strangers in the given geo!ogica! environment, as it is true with all other tektites, as well. Thus, the :lhamanshin crater сап Ье indeed regarded as а unique, if small, tektite strewn-fie!d . . 13. Comparison of the Zhamanshin and Austra!asian tektite chemistry shows а strong compositiona! resemblance in most cases. For instance, some tektites-zhamanshinites are identica! to MN-tektites from Indochina, and irghizites resemble S-tektites from Java, Australia and the Philippines, etc. 14. Specific !ayered black-yellow MN-tektite, though typica! to the Zhamanshin crater, were visually compared with the rare МN-tektite from Thai1and. Both g!1jsses.turned .out to Ье identica! in composition and in' fissi"n

track age ( - 1 т.у.) . . 15. Wide!y differentiated MN-tektite series (50-85% Si02) is а unique feature of the Zhamanshin crater. As mentioned аЬоуе, however, this !ongest MN-tektite series тау Ье presented in Thai1and, as well: 16. А summary of аН ауаi1аЫе radiogenic age data for tektites shows that

the common!y-accepted - 0.7 т.у. age of the AATSF is по more than convention. In fact, wide differences were found in ages of tektite (0.4 to 11 т.у.) аll !aying within опе young !ayer. Therefore, опе сап deduce that tektites of various ages accumu!ated at some extraterrestria! !осаОоп as а resu!t of periodic volcanic activity, and then were recently carried to the Earth and !anded together. 17. ТЬе Zhamanshin crater, if taken as а mode! of the ААТSF, he!ps to so!ve the !ong discussed problem of re!ationship between tektites and microtektites. Microtektites were originated together with tektites of the irghizite morpho!ogica! type, perhaps as а resu!t of ап excer-�ional1y turbu!ent volcanic process, whi!e normal shaped tektites were like!y produced Ьу а more quiet,' volcanic eruptions. Therefore, the presence or absence of microtektites in the !and strewn-fie!ds сап Ье connected with а specific morpho!ogica! type of tektites. 18. Serious doubts remain in respect to ,1 corre!ation of the AATSF tektites with the oceanic microtektites, because they both тау belong to different tektite falls. This particular problem requires more detailed investigation. For practically all the аЬоуе listed points, the Earth Impact ТЬеоту of tektite origin (EII) fai1s to provide adequate solutions without арреаl to numerous ad hoc assumptions. Indeed, the EIТ has practical1y; по theoretical or experimenta! basis. For instance, Е.уОп Enge!hardt et. а!. (1987, р.1) write" "Some problems are not yet satisfactori1y reso!ved, e.g. the transport of tektites

43 from craters to their pi:esent sites, the physico-chemica! conditions of tektite formation, and the parent materia!s. Ореп questions have given rise to controversia! hypotheses: extraterrestria! and impact". The main and practically so!e argument in support of the EIT is the striking geochemica! and isotopic resemblance bet\veen tektites and terrestia! sedimentary rocks, пате!у !oess, c!ayish sandstones (subgraywackes) or se!ected mixtures of quartz and с!ау. In light of the age-paradox, this similarity сап Ье interpreted in two a!ternative hypotheses. First, опе сап argue that tektites were produced within the Earth Ьу а still unknown processes, which !aunched tektites to space and returned them а !ong time after that. The mechanism of а terrestria! cryptoexp!osion has Ьееп discussed; however, it seems highly improbable, А second idea envisages а still unknown distant planet body geochemically resembling the Earth or, to speak more exact!y, with similar magmatic evo!ution trends. This idea was expressed Ьу тапу scientists,. mostly prior to the monopolization the thinking of scientific society Ьу the EIТ. The authors prefer the extraterrestria! idea, follo�ing J.O'Keefe, who deve!oped the theory of volcanic origin of tektites from the Мооп. However, after the АроНо missions, the Мооп does not seem to Ье the proper р!асе. The age-paradox span dictates that а more distant p!anet body shou!d Ье chosen. The idea Qf tektite delivery Ьу а specific eruptive comet (Izokh, Ап, 1983; Izokh, 1988) he!ps to untang!e the o!d tektite jig-saw puzz!e. It he!ps to fasten together а framework of а huge number of observationa! and ana!ytica! data Ьу some !ogica! though yet hypothetica! ties. In short, this рарег suggests that the Zhamanshin impact crater is а reaBy unique testing ground to check and to compare riva! theories of tektite origin. The crater is easily accessible and well exposed. The need for а joint investigation in the site has Ьееп noted Ьу тапу scientists (Р.F!ore nsky, S.Taylor, B.G!ass, V.Bou�ka, C.Koeber!, R.Grieve, etc.), though оп!у а few steps have Ьееп carried ои! so far. The formation of the Zhamanshin and the АЛTSF, as parts of the tektite puzz!e, has fundamenta! scientific significance not оп!у for p!aneto!ogy, cosmo!ogy and impact cratering, but a!so for igneous petro!ogy, Quarternary geo!ogy, ancient ' history, and for the problem of g!oba! climatic changes and mass extinctions оп the P!eistocenejHo!ocene boundary which тау Ье connected with а recent Earth-Comet collision, enormous tektite faB and. subsequent great catastrophe -10000 years ago. This "geo!ogicaly reeent Ьи! historica!y remote event "(Fenner, 1935, р.140) was discussed not !ong ago in the light of . . �' geo!ogica! facts and in the light of the ora! tradition of mankind,

44 an equally геуеаl ng source, with the latter helping to bring out the far reaching eultural impIications of this physieal event" (E.Tollman and A.Tollman, 1992, .5). Тhe autho� app eaL to the Scientijic Community for assistance in organizing the Zh mаnsЫn crater IntemationaL Joint Project, considering the fu ndamentaLsigni lcance о! the results obtained before and anticipated. AcknowLedg ments. The authors аге grateful to Dr. V.Masaitis for additional ehemi I analyses of the Zhamanshin target rocks and glasses, for specimens of d ер buried basic impaet glass and of remelted aeid zhamanshinite, а d for severe critique which sometimes turned to Ье eonstruetive. We ге obIiged to Drs. B.Mason, B.Fudali and R.Clarke from the Smithsonian Mus ит (Washington) for speeimens of the bIaek-уеllоw Muong Nong-tektite from Thailand, and to Dr. F.кytе from University of California (Los Angeles) for new Ir-analyses of the anomalous layer sequenee. The diseussions with B.Mason, C.Koeberl, B.Glass, Y.вoи�a, J.Wasson, B.Glass and espeeially with J.O'Keefe were helpful in formulating and sharpening arguments рго and contra extraterrestrial vs terrestrial tektite origin. То perform these diseussions we obIige to Раиl Barringer's personal support. We express our gratitude to V Akhmetova, T.Miryasova, A.Vladimirova and N.Кruk for assistanee in preparing this рарег. We аге much obIiged to John O'Keefe and Martha O'Keefe, and to Peter Smith from Language Media Centre (University of Texas) for translation the preIiminary text from our "Siberian English" to тоге eorreet usage.

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53 APPENDIX

Тhe /ollowing tables аге composed mostly о/ unpublished chemical analyses о/ tektites, impactites and target rocks used (о. plot various Harker's diagraтs in this рарег. All analyses with letter М (МlЗ/5, etc) belong (о V.Masaitis, and with letter F belong (о P.Florensky. Specimens with letter А (А 81-12, etc) were given (о us Ьу Le пис Аn /гоm his personal collection and were analyzed in Novosiblrsk All sp ecimens with letters Zh, тk ог without special indication belong (о E.Izokh and were analyzed in Novosiblrsk All analyses were obtained Ьу usual wet chemistтy method (Fерз and FeO analized separately), and Ьу соттоп instrumental х-гау fluorescent ог microprobe methods (only FeO ог Fе20з analized).

55 ТаЫе 1 Muong Nong-type tektites from Vietnam

N N Sp.# Si02 Тi02 АI2Оз FezОз FeO МNO MgO СаО a20 Kio L.i. Р205 Sum

1 А57 68.49 0.79 12.09 1035 0.12 2.55 1.87 1.73 222 . 0.05 10026 2 А61-1 69.78 0.87 11.93 8.90 0.12 2.82 2.03 1.41 235 0.05 10026 3 ТК1М 70.03 0.79 12.47 9.82 0.13 1.92 1.48 1.18 2.56 0.12 100.50 4 ТК22 7036 0.81 12.11 8.52 0.11 223 2.00 1.48 2.50 0.12 10024 5 61-2 70.42 0.78 1220 8.71 0.12 233 1.97 121 2.48 0.09 10031 6 А59 70.57 0.78 11.78 8.90 0.11 2.51 1.74 1.60 226 0.06 10031 7 ТК13 70.66 0.76 11.74 9.47 0.13 2.41 1.70 123 2.16 0.07 10033 8 А54 70.81 0.79 10.91 9.83 0.10 1.81 1.67 1.54 224 0.12 99.82 9 А55-1 72.00 0.79 12.00 5.62 0.08 2.79 1.92 1.50 225 0.06 99.01 10 А55 7234 0.79 1134 7.77 0.10 1.98 1.60 1.79 235 0.11 100.17 v\ 11 А65 72.76 0.80 1136 7.58 0.10 1.92 1.59 1.55 237 0.12 100.15 0\ 12 ТК23А 73.05 0.80 11.15 8.00 0.09 1.75 1.60 136 . 234 0.12 10026 13 А73-1 7320 0.84 1320 5.09 0.08 1.77 0.91 138 2.69 0.14 9930 14 А65-3 73.69 0:72 12.12 4.49 0.08 2.03 233 1.08 2.41 0.08 99.03 15 А64 74.03 0.76 11.03 7.02 0.09 1.58 1.54 129 225 0.11 99.70 16 А65-1 74.80 0.78 1137 4.74 0.07 2.00 1.85 1.56 · 225 0.11 99�3 17 А72 77.49 0.58 8.81 6.52 0.12 137 1.76 1.11 2.17 0.08 100Ш 18 ТК8 78.05 0.58 8.23 6.89 0.12 120 1.64 1.00 1.94. 0.07 99.72 19 ТК25 ' 70.00 0.79 12.47 8.56 0.11 2.00 2.19 1.18 2.53 0.08 99.91 20 ТК27 71.55 0.79 12.53 6.76 0.11 . 1.92 2.02 124 2.56 .о.08 99.56 21 А81-7 72.46 0.71 10.87 9.11 0.12 1.56 1.43 120 237 0.08 99.91 22 А81-2 72.53 0.75 11.07 8.82 0.14 1.49 121 1.61 236 0.10 100.08 23 ТК28 72.53 0.78 12.50 · 5.66 0.10 1.89 1.96 127 2.50 0.08 9927 24 А81-12 7320 0.72 12.00 0.59 4.49 0.10 1.86 1.76 1.60 2.50 032 0.09 9923 25 А81-8 74.10 0.75 11.60 0.78 3.95 0.09 1.81 1.70 1.57 2.44 0.56 0.08 99.43 26 А81-6/2 74.41 0.79 10.99 5.57 0.09 1.70 1.70 1.41 236 0.11 99.13 27 ТК26 74.48 0.78 12.00 5.45 0.11 1.85 1.87 0.93 2.51 0.09 100.07 28 А81-7 74.80 0.70 11.40 0.69 4.06 0.09 1.76 1.65 1.43 2.44 0.45 0.08 99.55 - 29 А81 6 75.10 0.68 10.90 0.42 435 0.10 1.58 136 1.50 2.44 . 030 0.09 98.82 30 А81-2 75.10 0.72 1130 033 424 0.10 1.60 127 1.43 2.44 0.43 0.00 98.96 31 А82М 75.16 0.72 10.14 8.47 0.12 1.41 123 1.03 2.44 0.10 100.82 32 ТК28М 7539 0.71 1135 6.69 0.12. 1.61 1.53 1.11 2.43 0.09 101.03 33 А83К 75.61 0.72 10.63 633 0.12 1.48 127 1.03 2.48 0.10 99.77 34 А81-1В 76.10 0.68 10.90 0.60 3.66 0.09 1.55 1.45 1.43 2.50 025 0.09 9930 35 А81-1А 76.10 . 0.77 10.70 029 3.77 0.10 1.54 121 1.43 2.50 036 0.11 98.88 36 А81-1А1 76.12 0.62 9.90 7.01 0.12 1.42 1.17 1.02 2.17 0.08 99.63 37 А83-1 76.80 0.66 1020 0.43 3.95 0.09 1.45 121 1.40 2.25 0.44 0.08 98.96 38 А82-1 77.40 0.60 9.90 0.54 3.88 0.11 138 132 1.40 231 0.43 0.01 9928 v> --J 39 11-1 79.40 0.63 9.60 3.94 0.08 1.16 1.10 131 2.06 0.09 9937

AVE 73.61 0.74 1125 0.52 6.59 0.10 1.82 1.61 135 237 039 Р.09 VAR 6.59 0.00 1.05 .0.02 427 0.00 0.16 0.10 0.04 0.02 0.01 0.00 SТD 2.57 0.07 1.03 0.15 2.07 0.02 0.40 032 021 0.15 0.09 0.03

Administrative Province and locality of specimens: South Vietnam_. A.jL8O km SE of Danang. МЫ: Phu Kanh, 100km SW of Qui Nhon. Ik..lm: 18 km N of Saigon. Ik..22: 10 krn WSW of Danang. �: Phu Kanh, 100km SW of Qui Nhon. �: Nghia Binh, 30 km NW of Quang Ngai. Th..U:50 km SW of Dalat, near Оа Dung. ЛЯ: 50 km SW of Danang. �, �,AjН�: 50 km SEaf Danang. �: Danang, 11 km NW of Тат Ку. A.n:l: Song Вe, 15 km NW of Bien Ноа. �, А...65:3: 50 km SW of Danang. А М: 40 km SE of Danang. . A.l2:Saigon, 10 km SW of Bien Ноа. Tk 8: 45 kin NW of Saigon: North Vietnam. Ik..2ill;�, к: Nghe Tinh, Nam Оап, -30 km WSW of Vinh. А 81-1 - A...8l:l1,А 82 -1, Ш. Nghe Tinh, DoLuong, 11:1: Nghe Tinh, 18 km W of Nge Оап. ТаЫе 2 Splash form tektites from North Vietnam

N Sp.# Si02 Тi02 Аl2Оз Fе20з FeO МпО MgO СаО Na20 КzO L.i. Р205 Sum

1 5 68.69 0.79 13.73 8.68 0.12 2.13 1.93 1.49 232 0.07 99.95 2 36 6928 0.77 12.03 9.64 0.13 1.98 2.68 124 234 0.07 100.17 3 17 69.59 0.75 12.80 10.13 0.12 1.94 1.95 121 236 0.06 100.93 4 А81/19 69.94 0.83 13.19 7.48 0.10 2.00 225 1.50 · 2.56 0.09 99.96 5 11 7028 0.80 1229 836 0.12 1.98 2.07 1.48 2.51 0.07 99.96 6 12 7028 0.80 12.50 8.13 0.12 2.09 2.08 1.16 2.58 0.07 99.81 7 ТК3О 7035 0.79 1237 8.24 0.12 2.03 233 0.84 2.05 0.05 99.17 8 22 70.42 0.74 11.99 8.84 0.13 2.00 2.70 i.05 228 0.06 10022 9 24 70.72 0.75 11.88 9.08 0.15 1.94 2.60 0.91 2.12 0.04 10021 10 33 70.74 0.77 12.09 830 0.13 2.05 2.44 1.17 236 0.06 100.11 11 А81-16 70.80 0.78 12.90 0.85 4.81 0.09 2.10 225 1.67 2.50 0.02 0.08 98.85 VI 00 12 6 70.85 0.80 12.47 7.76 0.11 2.02 2.09 1.45 2.57 0.07 10021 13 ТМ24В 71.03 0.76 11.90 8.42 0.12 2.01 2.12 129 2.44 0.08 100.18 14 34 71.03 0.82 12.84 7.03 0.12 2.09 2.74 1.03 221 0.06 . 99.97 15 А81С 7120 0.78 13.10 038 4.49 0.10 2.08 224 1.70 2.75 0.44 0.07 98.90 16 30 7134 0.79 12.94 6.89 0.12 2.10 2.65 0.89 2.17 0.06 99.97 17 А81/21 71.50 0.77 12.70 0.64 4.60 0.09 2.05 2.11 1.70 2.50 025 0.08 98.75 18 41 71.56 0.76 11.66 7.67 0.12 1.88 1.99 1.52 2.42 0.06 99.64 19 . 29 71.64 0.79 1225 7.68 0.13 2.01 2.51 1.04 228 0.05 100.40 20 А81/14 71.66 0.77 11.68 8.82 0.11 1.79 1.76 1.13 2.44 0.07 100.24 21 А81/17 71.77 0.78 12.11 7.95 0.11 1.82 . 1.83 1.44 239 0.06 10027 22 26 72.02 0.78 12.18 6.99 0.12 2.03 2.56 1.04 225 0.06 100.05 23 ТК42 72.07 0.77 11.96 6.91 0.11 1.83 1.88 121 237 0.03 99.15 24 А81/18 72.17 0.80 11.90 5.98 0.10 1.84 1.50 1.57 2.45 0.56 0.10 98.42 25 27 7228 0.73 12.01 6.95 0.12 1.91 231 1.05 2.14 0.05 99.57 26 ТК50 73.11 0.78 11.84 5.99 0.12 1.92 229 125 238 0.05 99.75 27 12-1 7З20 0.81 12.60 520 0.08 1.84 1.70 1.63 2.50 0.11 99.67 28 ТК29А 73.42 0.78 1237 5.72 О.11 1.85 1.78 120 2.40 0.05 99.69 29 19 73.54 0.75 11.73 6.46 0.10 1.95 2.07 1.01 226 0.03 99.91 30 9-1 73.60 0.79 12.80 4.70 0.08 1.76 1.78 1.50 2.50 0.10 99.63 31 7-1 73.70 0.79 1230 4.59 0.08 1.76 1.76 1.63 2.50 0.09 9921 32 А-83 73.86 0.69 10.65 7.43 0.13 1.54 133 0.99 236 0.09 99.07 33 18-1 73.90 0.79 12.50 4.55 0.08 1.90 2.06 1".56 225 0.03 99.63 34 8-1 7420 0.80 1220 436 0.07 1.76 1.85 1.56 2.50 0.11 99.43 35 29-2 7431 0.73 12.51 4.42 0.09 1.77 2.70 0.78 225 0.05 99.61 36 33-5 74.56 0.73 12.49 4.46 0.09 1.72 2.43 1.12 2.49 0.06 100.17 37 19-1 74.60 (J.80 12.40 4.74 0.08 1.86 220 1.44 2.13 0.07 10033 38 24-1 74.60 0.79 12.70 4.89 0.09 1.86 236 1.19 2.13 0.05 100.68 39 10-1 74.90 0.78 1220 4.51 0.07 1.79 1.92 1.56 2.50 0.09 10033 40 30-1 7520 0.85 12.50 4.59 0.09 1.79 1.92 1.13 2.13 0.05 100.26 v1 АУЕ 72.10 0.78 1233 0.62 6.66 0.11 1.92 2.14 128 237 0.07 � VAR 2.94 0.00 027 0.04 . 3.00 0.00 0.02 0.12 0.07 0.02 0.00 STD 1.71 U.U3 0.52 0.19 1.73 0.02 0.13 034 026 0.16 0.02

Administrative province and locality : �: Nghe Tinh, 5 km N of Qиy Нор 3Q.:Вас Тhai, Cho Oon. 1L: Nghe Tinh, 40 km "NW of Соп Cuong. А 81-14-21 : Nghe Tinh, 00 Luong. l1..: Nghe Tinh, 18 km SE of QиaRao. 1L: Nge Tinh, 30 km SE pf Qиy Нор. IkJQ..: Вас Thai, near Тhai Nguyen, to S. 22 :На Tuyen, 27 kщS of Tuyen Qиаиg. 24 : На Tuyen, Нат Уеп. 3J..: Vinh Phu, 5 km N of Phu Tho. �: Nghe Tinh, 12 km NE of Qиy Нор. Tk24Ь .: Nghe Tinh, Nam Оап. 3i.: Vinh Phu, W of Viet Tri. 30 .: Hoang Lien $оп, within the Уеп Bai City. nя:На Nam Ninh, near Ninh ВinЬ. �: Hoang Lien Son, 10-13 km WNW of Уеп Bai. :rк..gQиang : Ninh, near Mong Cai. 2'1-: На Tuyen, Нат Уеп. Th 5Q : Vinh Phu, near Phu Тhо. Ш : Nghe Tinh, 30 km SE of Qиy Нор. _Tk 29 .: Qиang Ninh, пеат Hong Gai. l8:1....12.: На Son Binh, 30 km W of Hanoi. 2;L: Nghe Tinh, 15 km Е of Qиi Нор. 1:1..: Nghe Tinh, пеат Qиy Нор, to NNE. А..Ы.:Nghe Tinh, Nam Оап. 8:L: Nghe Тinh, 41 km Е of Qиy Нор. 22:2..:Hoang Lien Son,-WNW of Уеп Bai. �: Vinh Phu, 5 km N of Phu Тho. 12:L:На Son Binh, 30 km W of Hanoi. �: На Tuyen, Нат У en. lll: Nghe Tinh, 52 km Е of Qиy Нор. ЗQ:L: Hoang Lien Son, within Уеп Bai City.

# 28, 31, 37, 38: layered spheres, the transition form between S-tektites and MN-tektites. Table 3 Splash form tektites from South Vietnam

N Sp.# Si02 Тi02 А12Оз F�Оз FeO МпО MgO СаО N'ap К2О L.i. Р205 Sum 1 А27 68.67 0.84 13.34 931 0.15 335 1.92 0,84 2.01 0.05 100.48 2 ТК1 68.77 0.77 1233 1023 0.13 2.42 1.77 136 233 0.06 100.18 3 А69 68.91 0.75 11.01 1233 0.13 2.66 1.84 1.17 1.88 0.04 100.73 4 ТК19 69.08 0.76 11.79 10.11 0.13 2.60 227 137 230 0.08 10051 5 А18 69.43 0.77 11.99 932 0.12 2.49 223 128 223 0.08 99.94 6 А39 6953 0.79 12.34 9.81 0.13 НО 1.88 121 226 0.06 100.42 7 А5О 69.68 0.78 11.75 9.98 0.13 252 1.87 135 2.11 0.06 10023 8 А34 69.71 0.81 12.34 8.77 0.13 3.02 222 1.19 2.14 0.06 100.41 9 ТК17 69.73 0.78 11.62 10.49 0.15 2.60 1.92 130 222 0.06 100.87 10 К20 ·69.74 0.76 1233 9.14 0.13 2.42 1.89 125 227 0.06 100.00 11 А4 69.74 0.75 11.96 9.76 0.14 2.48 1.77 0.91 226 0.06 99.83 12 А19 69.76 0.75 11.42 10.73 0.14 223 2.18 1.10 230 0.08 100.70 13 А12 69.82 0.80 11.52 10.13 0.11 232 2.18 128 2.41 0.09 100.66 0\ 14 с> А40 69.83 0.80 12.03 1026 0.14 231 1.91 121 233 0.05 100.89 15 ТК12 69.87 0.80 1225 932 0.12 236 2.01 1:30 2.47 0.07 10058 16 А79 69.90 0.77 11.72 9.09 0.12 328 2.07 1.61 237 0.08 101.02 17 А42 69.95 0.81 12.03 9.50 0.12 2.71 1.94 134· 2.19 0.04 100.63 18 А3 70.10 0.77 1227 8.14 0.12 2.47 222 1.44 225 0.08 99.87 19 А60 70.13 0.79 11.96 923 0.12 2.51 1.79 127 224 0.05 100.11 20 44 70.19 0.83 12.42 8.80 0.12 2.00 2.13 158 2.65 0.10 100.82 21 А22 7020 0.77 1227 7.99 0.11 2.50 2.07 125 . 233 0.08 9958 22 . А47 7021 0.79 11.90 9.18 0.12 2.65 1.95 126 230 0.05 100.43 23 ТК13 7022 0.77 12.09 9.14 0.13 2.55 1.78 1.17 2.28 0.06 100,20 24 А31 7027 0.80 11.96 932 0.14 2.66 1.91 1.34 230 0.06 100.77 25 ТК18 7030 0.80 11.97 932 0.13 2.60 1.99 1.17 235 0.07 100.71 26 А82/1 7030 0.80 12.14 8.68 ол 1.87 2.13 1.41 2.67 0.10 10022 27 А82/24 7039 0.78 12.50 8.87 0.11 1.83 1.96 120 2.54 0.06 10024 28 А29 7039 0.79 11.99 1024 0.13 232 1.91 137 238 0.07 101.61 29 А25 70.49 0.74 10.81 10.48 0.11 237 1.91 139 2.14 0.06 100.51 30 А9 7050 0.76 11.10 9.58 0.11 239 2.17 152 229 0.08 10050 31 А38 70.54 0.79 11.85 8.65 0.12 2.93 225 1.06 2.07 0.06 10033 32 А33 70.66 0.79 12.07 8.82 0.14 2.59 1.88 1.06 225 0.06 100.34 33 43 70.71 0.75 1229 6.89 0.11 2.34 220 139 238 0.10 99.17 34 А5 70.89 0.76 11.98 · 8.15 0,14 2.61 1.81 0.98 226 0.08 99.68 35 А28 70.89 0.75 Н.83 9.00 0.12 2.42 1.92 1.04 220 0.07 }0О24 36 А13 71.17 0.75 11.79 831 0.11 239 2.05 1.13 223 0.07 100.01. 37 Аб 71.17 0.79 12.55 7.34 0.11 2.45 1.76 124 235 0.06 99.84 38 А52 7122 0.78 11.54 8.63 0.11 225 1.70 1.56 238 0.08 10026 39 А53 7133 0.78 11.60 8.47 0.11. 2.50 1.78 139 233 0:07 НХ>36 .40 А1 71.51 0.69 11.87 7.91 0.12 2.17 1.51 1.05 2.14 0.05 99.04 41 1 72.40 ·0.78 1230 5.44 0.10 2.64 1.57 125 225 0.10 98.83 42 А17 72.45 0.74 10.84 8.78 0.10 1.81 1.70 . 1.40 236 . 0.09 10028 43 А63 72.47 0.74 10.34 9.87 0.10 1.57 1.50 131 222 0.11 10024 44 39 72.73 0.81 11.78 7.11 0.11 1.87 1.90 1.49 225 0.04 100.09 45 А84 73.58 0.67 10.75 7.96 0.11. 1.45· 1.07 1.82 238 0.10 99.91 46 А73 7420 0.63 924 923 0.13 1.66 1.52 135 2.19 0.07 10022

0\ АУЕ 70.52 0.77 11.82 9.08 0.12 2.40 1.91 128 228 0.07 .... УЛR 135 0.00 0.43 128 0.00 0.14 · 0.06 0.03 0.02 0.00 STD 1.16 0.04 0.66 1.13 0.01 . 038 024 0.18 ·0.14 0.02

Administrative province ;ptd locality .: AI1: Тhиап Hai, near РЬап Rang. тk .1: 18 km N .of Saigon. А 69 .: Nghia ВшЬ, 60 km NNW of Qui Nhon. Ik..l2:Тhиап Hai, Саре Ка Na. A.l8 : 20 km S of Сопgtuш.�: Тhиап Hai, РЬап Тhiet. AjO:Nghia ВinЬ, 20 km W of Quang Ngai. �: Nghia Binh, 4Okm S of Qui NhoIf.Ik..11: Lam Dong, Da Pren. Ik.2Q: Lam Dong, Кrong РЬа, Е of Dalat. М: Тhиап Hai, РЬап Ri. А 19 .: 10 km S of Сопgщт. A..U near Сопgщт to NE. �: ТЬиап Наi,ЗOkm NNE of РЬап Тliiet. Th.1:Lam Dong, Вао Loc.A1!l.: Dac Lac, Nguyen Lac Nong. Ад2: РЬи Кhаnh, 40 km NNW of Nha T� ang. &.3: Lam Dong,80 km SW of Dalat. fiQ: Nghia Binh, зо km NW of QuangNgai. 44:Nge Tinh, Тап Ki. А 22: Nghia Binh,.60 kщ WNW of Qui Nhon. AS1:Nghia ВinЬ, зо krnSSW of Quang Ngai. Ik..U: Lam Dong, Вао Loc.A..Jl: цт pong, t: of Dalat. Ik.18: Lam Dong, Dalat city. А 82-1.А 81-24: NgheTinh, Do Luong. А..22: 40 km SW of Dalat. �: Nghia Binh, 8ОkшNW of Qui .Nhon. AJl: 20 km SSW of Congturn.А...38: Nghia Binh, 80 krn SSW of Qui Nhon. А..33: Lam Dong, 50 km S of Dalat. 13: Danang, Тат Ку. А2:Тhиап Hai, 5 km S of РЬап Rang. А.28:Тhиап Hai, 40 km SW of РЬап Rang. A.n: near Congtum eity. �: Тhиап Hai, NW of РЬап Rang. Aj2: Nghia Binh, N of Quang Ngai. A..j3.: W of DanaI).g. A..1: Dong Hai, Bien Ноа. 1: Dalat city. A.l1: 20 km NW of Сопgщт. A...БJ: Binh Tri Тhien, Quang Tri. 32: Dac Lac, Dac Nong. A:D.. Dong Nai, Bien Ноа. ТаЫе 4 lЗ lасk-уеllоw layered Muong Nong-type tektite from Thailand

N Sp.# Si0 Тi0 А1 О Fe О FeO МNO MgO СаО Na 0 К О Lj. Р 0 Sum 2 2 2 з z з . 2 2 2 5 1 1 67.01 0.96 15.18 5.68 0.09 2.52 3.16 0.87 2.80 0.00 0.00 9827 2 2 68.50 0.90 1422 524 0.09 238 3.10 0.76 2.84 0.01 0.02 98.06 3 3 67.14 0.94 14.80 5.52 0.09 2.50 3.43 0.78 2.63 0.02 0.01 97.86 4 4 68.91 0:88 1428 5.44 . 0.08 229 2.57 0.77 2.77 0.00 0.00 97.99 5 5 70.06 0.87 13.51 5.17 0.08 225 2.94 Н)5 2.76 0.02 0.01 98.72 6 6 68.84 0.91 1421 5.00 0.07 221 2.94 1.09 2.82 0.00 0.02 98.11 7 7 70.12 0.85 14.89 5.15 0.08 1.87 1.56 0.87 3.06 0.01 0.01 98.47 8 8 68.90 0.89 14.10 528 0.00 231 3.00 1.05 2.79 0.00 0.02 9834 9 9 67.07 0.92 14.80 5.66 0.09 2.52 327 126 2.69 0.01 0.00 9829 01 N 10 10 72.17 0.82 12.67 4.53 0.06 1.94 2.45 0.92 3.03 0.00 0.01 98.60 11 11 68.77 0.86 13.99 534 0.08 232 3.03 1.06 2.80 0.02 0.01 9828 12 12 69.74 0.83 13.56 4.88 0.08 2.15 2.86 0.86 2.86 0.00 0.00 97.82 13 13 69.67 0.84 13.40 4.97 0.08 225 2.79 1.02 2.95 0.02 0.02 98.01 14 14 68.70 0.90 14.68 528 0.08 2.10 1.91 0.93 3.18 0.00 0.01 97.77 15 15 68.43 0.70 14.47 533 0.08 235 2.93 1.14 2.89 0.00 0.00 9832 16 16 74.01 0.78 11.97 3.95 0.06 1.68 223 1.00 3.11 0.00 0.01 98.80 17 17 69.46 0.86 13.44 528 0.00 228 2.85 1.01 2.90 0.02 0.02 98.12 18 18 69.91 0.86 13.46 5.10 0.08 2.16 2.89 1.03 2.88 0.01 0.00 9R38 19 19 69.67 0.84 13.52 5.19 0.07 229 2.83 0.88 2.79 0.02 0.01 98.11 20 20 70.59 0.83 13.03 5.05 0.08 221 2.72 1.04 2.84 0.01 0.02 98.42 АУЕ 6938 0.86 13.91 5.15 0.07 223 2.77 0.97 2.87 0.01 0.01 VAR 2.58 0.00 0.63 0.14 0.00 0.04 0.19 0.02 0.02 0.00 0.00 STD 1.60 0.06 0.79 038 0.03 021 0.44 0.13 0.13 0.01 0.01

Specimen # 6265 from the Smithsonian Museum tektite collection (Washington). Microprobe profile ТаЫе 5 Black-yellow layered Muong Nong-type tektite from Zamanshin crater. Microprobe ()rofile

, e � u N Points Si02 Тi02 А12Оз FezОз F O МNO MgO СаО N 20 К2,? Р205 S in , 1 22 75.15 0.73 12.81 4.47 0.09 0.72 0.43 0.49 2.97 0.01 97.88 2 23 7133 0.90, 15.50 523. 0.10 0.91 051 0.55 2.85 0.02 97.91 3 24 ' 64.71 1.07 20.10 6.68 0.13 120' 058 0.86 2.75 0.01 98.11 4 25· 7453 0.75 , 1337 5.06 0.09 0.83 0.49 053 2.85 0.00 9850 5 26 74:61 0.78 13.98 436 0.07 0.74 038 036 ,2.99 0.02 9830 6 27 80.62 0.55 1025 ' 4.08 0.07 0.58 038 037 2.63 0.00 99.53 7 28 73.93 0.80 13.76 5.02 0.08 0.80 0.48 055 ,2.85 0.01 9828

0'\ 8 ' 29 75.67 0.73 13.08 434 0.08 0.72 0.43 0.41 2.90 0.02 9839 w 9 зо 71.11 0.87 1534 5.91 0.11 0.93 056 0.63 2.77 0.00 9825 10 31 72.16 0.83 15.19 536 0.09 0.87 0.47 053 2.91 0.01 98.42 11 32 67.46 0.90 16.68 6.89 0.13 1.12 0.69 0.76 2.74 ' 0.02 97.40 12 33 74.89 0.72 12.89 5.02 0.09 0.78 0.48 0.58 2Я4, 0.00 9.823 13 34 73.75 0.75 1356 539 0.09 0.84 050 0.46 2.85 0.01 9821 14 35 73.74 0.74 12.88 555 0.09 0.89 056 0.54 2.81 0.02 97.84 15 ,36 7223 0.83 14.42 ' 5.91 0.10 0.95 0.61 0.43 ' 2.86' 0.00 9835 16 37 72.71 0.75 1358 ' 4.93 0.09 0.78 '0.47 050 2.95 0.01 96.79 17 38 6733 0.92 18.11 632 0.11 1.01 0.60 0.83 2.72 0.02 97.97 18 39 75.93 0.67 11.94 4.72 0.09 0.69 054 038 2.94 0.00 97.91 19 40 71.07 0.87 15.69 5.72 0.11 0.96 052 0.63 2.87 0.01 98.47 АУЕ 73.00 0.80 1438 531 0.10 ОМ 051 055 2.84 0.01 VAR 1626 0.01 4.79 059 0.00 0.02 0.01 0.02 277 0.00 sm 4.03 0.11 2.19 0.77 0.02 0.15 0.08 0.14 0.09 0.01 �aЫe 6 . Zhamansbln impact crater: low-sШса part о! the Muong Nong�typetektite series u N Sp.# Si� Тi02 А12Оз FezОз FeO МNO . MgO СаО Na;O К2О Lj. Р205 S m 1 MI5W2 50.85 1.54 32.66 2.IJ7 0.07 1.16 0.85 155 4.76 0.00 96.41 2 М20МЗ 53.71 1.06 2725 8.17 0.01 1.74 0.93 224 139 . 0.01 . 9652 3 М15Il 53.97 120 24.71 10.43 0.08 0.97 055 . 051 133 0.02 93.79 4 M�3 54.06 1.13 27.94 8.45 0.14 0.74 1.92 126 2.00 0.01 97.66 5 М21К 5427 0.91 23.44 726 2.42 028 1.09 124 131 1.19 6.72 0.00 100.13 6 М8В2 5526 1.54 25.94 2.87 0.40 0.14 0.97 0:52 133 0.82 934 0.00 99.13 7 МI8-1 55.95 138 24.95 1027 0.01 1.12 1.41 1.03 1.98 0.01 98.13 · 8 � 5639 · · 1.02 25.02 7.72 020 1.44 152 ' 1.03 2.92 0.01 9727 9 М2Ю 5650 2.90 28.10 2.64 1.87 0.08 0.44 0.64 0.96 027 5.94 0.02 10036 10 МЗ2G1 56.54 134 2356 Ч3 050 3.97 0.78 139 3.69 0.00 99.10 0'\ 11 33R 5655 133 28.87 8.83 0.01 038 0.15 · 0.71 1.76 0.01 98.60 .j>. 12 М20-01 57.11 1.17 2422 4.74 4.43 0.15 136 2.93 124 1.83 0.70 0.02 99.90 13 МI8-2 • 5730 . 1.16 23.82 6.78 0.19 151 3.09 1.63 1.80 0.00 9728 14 МI512 57.41 1.09 25.46 758 0.13 0.61 151 1.13 1.67 0.01 96.62 15 39D-2A 57.82 120 17.71 2.44 5.73 0.11 1.11 5.93 0.97 1.00 2.48 0.12 9Р.62 16 МI9-1 5830 132 24.06 7.63 0.07 1.15 2.14 134 225 0.01 9827 17 М19-2 58.49 1.10 2335 756 0.06 1.18 336 127 2.03 0.02 98.44 18 37R-l' 5852 130 23.54 1.75 830 0.14 1.43 1.13 0.83 1.40 1.45 0.15 99.94 19 , . MI5W3 58.62 . 1.02 18.10 6.54 024 4.46 4.80 . 1.99 222 0.01 98.01 20 460-2 · 6026 1.15 2232 224 7.80 0.09 0.92 ,0.99 1.19 2.04 0.86 0.17. 100.03 21 19-1 61.80 0.90 1856 133 826 0.18 120 1.96 2.00 257 0.60 0.15 9951 22 М15 6231 1.05 18.11 5.12 .0.08 3.52 2.47 2.67 2.86 ' 1.81 0.00 100.00 23 F4 62.88 1.10 21.15 6.44 1.03 0.44 1.10 2.16 1.46 1.99 0.01 ' 99.77 АУЕ 57.17 126 . 24.04 138 , 633 0.15 1.46 1.87 135 1.99 131 0.03 VAR 8.03 0.15 13.08 452 7.80 0.01 1.07 1.90 024 ·0.87 6.16 0.00 SТD 2.83 039 3.62 2.13 2.79 0.12 1.04 138 0.49 0.93 2.48 0.05

## 10, 11, 20-22: dark lenses within the yeHow pumice; аН other sPecimens: dark fine-vesicular pumices. ТаЫе 7 Zhamanshin impact crater: medium-silica part of the Muong Nong-type tektite series

N Sp.# Si02 Тi02 АIzОз FezОз · FeO МпО MgO СаО . Na20 К2О L.i. Р205 Sum 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

1 39А-2 63.44 1.12 17.05 1.97 5.94 0.10 122 4.68 1.07 1.13 1.83 0.17 99.72 2 M15W2 63.30 1.00 15.59 6�74 023 3.40 3.52 138 325 0.00 98.41 3 32G2 63.82 1.07 1731 736 034 ·233 1.49 1.57 3.10 0.01 98.41 4 45W1 64.12 1.11 20.05 0.50 7.fiJ 0.10 1.02 0.85 135 2.12 0.84 0.17 99.83 5 37W2 6428 1.02 19.90 . 1.06 636 0.11 131 0.85 123 2.68 0.79 0.15 99.74 6 M15W2 64.43 0.94 15.fiJ 6.72 022 2.70 2.67 1.40 331 0.01 98.02 7 М15 64.52 О.93 15.74 622 0.11 3.16 3.48 1.89 2.80 1.17 0.00 100.02

0\ 8 М33 64.64 1.50. 16.96 1035 0.96 0.48 '0.52 1.03 2.83 0.01 9929 v> 9 М20М 65.00 1.58 22.69 0.45 3.69 0.08 0.74 0.99 0.75 129 2.57 0.02 99.85 10 4OW-2 65.14 1.05 1637 2.86 5.53 0.10 133 2.55 1.61 1.77 1.02 0.15 99.48 11 M32G 65.30 120 1325 3.10 5.00 032 1.84 2.fiJ 1.65 2.70 2.18 · 0.00 9.9.14 12 M15W3 . 65.58 0.90 15з1 629 0.08 2.44 2.95 1.45 339 0.02 98.48 13 0-5А 66.00 0.95 16.08 0.62 8.Q1 0.85 1.80 0.42 1.10 1.88 1.5Е 0,20 99.49 14 39G 6636 125 17.72 1.18 6.68 0.10 1.02 1.84 135 1.86 0.40 0.18 99.94 15 . 19-5 66.40 0.89 15.15 1.00 8.14 037 1.80 126 1.50 2.50 0.44 020 99.65 16 300 66.40 0.88 16.19 1.63 2.56 025 132 2.13 0.55 3.72 3.78 020 99.61 17 37Е 66.44 0.90 17.04 0.79 7.85 0.13 122 1.56 1.42 2.45 0.06 0.15 100.01 18 05Ь 66.66 0.95 14.18 0.69 723 0.15 4.30 126 1.10 2.14 0.80 0.11 99.57 19 05w 66.68 1.13 17.89 0.18 6.73 0.16 120 0.98 125 2.57 0.73 0.13 99.63 20 36О 66.80 0.85 15.85 134 627 0.14 1.43 0.99 1.53 2.57 2.04 0.15 99.96 21 FЗ 66.83 1.04 18.56 3.83 4.fiJ 0.12 1.16 2.01 125 1.77 0.00 0.07 10124 22 370 67.00 0.90 1720 0.81 7.02 0.11 121 0.71 122 2.64 0.82 0.13 99.77 23 .4ОВ 6728 1.50 2026 532 0.00 0.83 0.62 1.06 1.75 0.00 98.62 24 М12О 6732 0.87 17.fiJ 2.16 2.10 0.06 0.89 1.00 0.48 3.42 328 0.01 99.19 25 36G 67.42 1.02 18.05 0.75 5.86 0.10 122 0.85 138 2.76 0.64 0.17 10022 ТаЫе 7 (e nd} 1 2 3 4 5 6 7 8 9· 10 11 12 13 14 15

26 ЗOw 67.80 0.84 15.19 0.66 6.81 0.13 122 1.98 0.45 2.82 0.95 0.19 99.04· 27 39Ь 68.02 0.74 15.03 1.89 5.53 0.11 0.92 2.55 1.75 2.72 0.34 025 99.85 28 ВSЗ6G 68.05 0.77 1525 138 422 028 1.06 0.58 1.50 2.68 2.82 0.16 98.75 29 38ZH 68.12 0.70 11.13 0.67 5.45 0.09 1.53 2.69 135 236 5.48 0.17 99.74 зо М20М2 68.34 1.17 18.84 0.70 5.19 0.13 1.09 0.45 1.10 1.97 0.58 0.00 99.56 31 51-88 68.63 0.85 1536 6.52 0.12 121 0.76 1.71 2.71 130 0.12 9929 32 32-zh 68.78 1.06 1520 1.49 533 0.08 1.02 1.14 1.50 2.50 123 0.19 99.52 33 М21N1 68.88 1.05 17.53 4.97 0.10 125 031 1.34 2.60 0.02 98.06 з4 M21N2 69.49 0.98 1636 520 0.10 1.10 0.56 1.76 3.01 0.02 98.60 35 32О 69.50 0.90 12.74 1.11 6.07 0.15 2.04 2.13 120 2.86 1.03 028 100.01 з6 М32В 69.60 0.92 14.16 132 2.60 0.10 126 1.15 1.82 3.17 3.16 0.00 ' 9926 37 3Th 69.90 0.85 15.18 1.18 6.07 0.10 1.10 0.71 138 2.57 0.82 0.14 100.00 з8 BS5A 7022 1.22 16.74 0.85 3.89 030 0.98 0.56 128 2.16 1.02 0.16 9938 39 ЗЮ 70.86 0.88 12.07 1.% 5.02 0.11 1.74 1.99 120 2.71 . 0.97 025 99.76

АУЕ 66.86 1.01 1637 131 5.87 0.18 1.51 1.55 131 2.54 1.15 0.11 VAR 3.93 0.04 5.03 0.69 2.57 0.03 0.59 1.04 0.11 032 1.48 0.01 SТD 1.98 020 224 0.83 1.60 0.19 0.77 1.02 033 0.57 122 0.09

## 4, 13, 14, 16-20, 25, 26, 28, 35: yellow pumices; # 19 - yellow glass; ## 1, 3, 4, 10, 15, 22-24, 27: altemating dark (low silica) and yellow pumices; # 35: alternating yellow pumice and black (acid) glass. Detaile discriptions of other specimence are not available. ## 28, з8- from (Вoи�a et al., 1981); # 21 - from (Florensky and Dabizha, 1980). . ТаЫе 8 ZhamanShin impact crater: medium to acid part of the Muong Nощ�-typе tektite series

N Sp.# Si0 Ti� Аl О F�О FeO МNO MgO СаО Na 0 К О Li Р 0 Sum 2 2 з з . 2 2 2 5 1 31k 70.04 0.99 14.85 0.97 6.90 0.07 1.12 1.14 1.14 257 028 0.17 10024 2 31р-3 70.04 0.92 13.60 12Т 6.57 (}.12 1.02 128 131 229 120 0.17 99.79 3 37r-3 7020 132 17.87 034 5.41 0.08 020 1.14 0.83 133 0.57 0.11 99.40 4 т-З3 70.41 1.10 16.47 5.58 0.12 1.15 0.47 132 2.09 0.00 98.71 5 тВа 70.68 1.14 17.08 434 0.02 0.95 032 0.92 2.03 01)1 97.'!IJ 6 2Ь 70.85 120 1630 031 4.85 0.09 0.94 .123 129 1.77 0.63 0.10 99.56 7 39а-l 7120 0.99 14.68 132 520 0.08 0.41 1.56 1.55 2.72 025 022 100.18 8 ЗQЬ 7122 0'.99 15.53 0.70 4�87 0.08 0.51 1.98 0.61 2.45 0.56 0.17 99.67 9 39d-2b 71.76 0.80 12.78 120 624 0.11 1.11 0.85 1.77 2.83 0.14 0.12 99.71 10 2d 71.90 0.74 12.66 0.89 5.08 · 0.11 220 1.08 1.54 2.76 0.55 0.02 99.53 11 37w-l 72.00 0.78 14.17 1.07 5:41 0.09 1.10 0.71 138 2.64 0.59 0.10 100.04 12 · 31w 72.02 0.71 12.49 1.16 4.73 0.09 1.12 1.14 3.00 3.00 1.02 0.16 100.64 cf\ 13 20d 72.00 0.73 13.'!IJ 126 4.83 0.05 0.90 0.84 1.85 3.14 0.59 0.15 99.84 -J 14 23Ь 72.00 0.61 14.41 6.49 0.12 1.00 0.77 1.80 3.10 0.11 100.41 15 4ОЬ 7227 0.90· 1435 129 4.63 0.09 9.91 . 0.10 1.58 2.48 037 0.11 108.68 16 ЗОе 72.66 0.63 1130 236 4.66 0.09 0.51 1.84 1.64 3.00 0�75 · 0.19 99.63 17 12w 72.72 0.66 1131 1.40 6.19 0.14 1.00 0.98 1.75 3.00. 030 0.15 99.60 . 18 22w 72.72 0.66 11.98 0.06 5.95 0.16 120 ·0.91 2.00 3.10 0.66 0.18 99.58 19 31d 72.78 0.72 12.67 0.88 5.16 0.07 123 1.14 1.71 3.07 0.84 0:16 100.43 20 26w 73.02 0.69 12.15 0.91 4.69 0.10 133 128 1.79 2.92 034 0.17 . 99.39 21 43w-2 73.06 0.71 12.52 1.01. 520 0.(),7 1.02 1.14 1.73 2.75 0.57 0.15 99.93 22 5 73.12 0.82 12.99 0.47 5.80 0.13 0.80 1.08 1.57 2.40 0.63 0.17 99.98 23 45d 73.12 0.76 1336 2.62 3.14 0.07 0.82 0.99 1.78 2.92 034 0.15 100.07 24 2Ь 73.44 0.75 12.66 0.75 4.62 0.11 1.40 0.95 1.75 2.60 0.80 0.08 99.91 25 4Ow-l 73.73 0.80 12.66 0.77 5.03 0.09 0.71 0.99 1.73 2.01 0:41 1.11 100.04 . 26 12d 73.73 0.56 9.09 135 5.78 0.10 2.70 0.70 1.80 2.93 0.63 0.14 . 99.51 27 33r 73.84 0.71 12.48 1.03 4.95 0.10 1.02 0.99 1.53 2.70 0.54 0.13 100.02 28 31Ь 74.06 0.73 13.00 0.83 4.46 0.09 1.02 0.99 1.50 3.07 0.10 0.18 100.03 AVE 72.16 0.83 13.53 1.05 524 0.09 137 1.04 1.58 2.63 . 0.49 0.17 VAR 1.41 0.03 . 3.50 030 . 0.62 0.00 2.93 0.12 0.18 020 0.09 0.04 sm 1.19 0.19 1.87 0.55 0.79 0.03 1.71 035 0.42 0.44 029 0.19 Layered yel\ow and general\y prevailed biack acid gJasses. ТаЫе 9 Zhamanshin impact crater: acid part of the Muong Nong-type tektite series.

N Sp. # Si02 Тi02 А1Рз F�Оз FeO MnO MgO СаО Na20 К2О L.i. Р205 Sum 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

1 M15Z 7035 0.88 15.16 532 021 0.82 0.42 1.41 229 0.00 96.86 2 М8В-l 70.58 0.62 1039 5.45 023 1.86 558 1.42 235 0.01 98.50 3 М8В-2 70.84 0.77 1332 523 0.05 1.51 129 1.77 2.94 0.02 97.76 4 М8А-l 7130 1.07 16.78 3.18 0.01 0.54 0.18 0.92 1.82 0.01 95.82 5 М8В-3 71.62 0.75 1324 4.57 0.19 126 1.64 1.74' 3.1 0.00 98.11 6 МD2 71.70 0.87 1559 1.78 4.50 0.19 0.97 0.74 1.48 2.63 0.51 0.08 101.04 7 МIА-l 71.86 0.73 12.67 428 0.15 0.94 054 129 2.48 0.01 0.01 94.96 8 ВS20-5 71.97 0.72 13.44 124 4.64 024 0.72 058 1.46 2.72 1.6 0.15 99.48 9 20В 72.10 058 10.46 1.06 826 0.11 0.80 1.11 1.75 2.73 0.54 0.14 99.64 0\ 10 BS9 7224 0.61 10.63 0.98 3.43 0.18 1.06 2.70 1.68 2.78 2.62 058 99.49 00 11 М8В-4 7230 0.50 11.07 4.53 0.11 121 335 1.79 2.73 0.00 9759 12 МIА'2 72.42 0.75 12.46 4.93 0.12 0.85 0.59 128 2.68 0.01 96.10 13 3ОА 72.76 0.67 11.98 0.92 5.62 0.11 0.81 1.42 1.78 3.00 0.11 021 9939 14 М22-2 72.84 057 12.45 3.83 0.00 131 2.61 1.01 223 0.02 96.87 15 6-1 72.94 0.73 12.96 0.46 5.04 0.16 1.10 0.95 1.87 2.86 0.55 0.03 99.65 16 M15Z 72.94 0.86 13.92 5.00 0.09 1.16 0.56 1.19 2J)2 0.01 98.36 17 М22-1 72.96 0.45 11.84 3.67 0.12 131 2.61 1.01 223 0.00 9620 18 12Е 73.00 0.70 10.10 135 6.07 0.12 1.11 1.11 1.75 2.86 1.36 0.14 99.67 19 4 73.50 0.68 12.49 0.7 4.12 0.1 12 1.49 1.87 3.00 0.46 0.11 99.72 20 MD8 73.55 0.76 14.12 1.9 3.36 0.15 0.97 054 1.48 2.90 037 0.00 100.10 21 зж 73.80 0.62 11.69 0.97 5.54 0.1 0.51 1.42 1.78 2.81 0.14 0.15 99.53 22 2Е 73.82 0.80 13.33 0.79 4.13 0.11 0.9 0.95 1.56 2.66 0.45 0.03 9953 23 31А 73.97 0.71 12.81 3.87 0.06 0.99 0.40 1.88 3.15 0.00 97.84 24 К-91 74.00 058 11.02 4.47 0.1 133 4.08 1.52 2.70 0.8 100.61 25 23-4 74.17 0.70 13.10 034 42 0.13 0.95 0.91 2.05 3.00 0.48 0.16 100.19 26 22В 7420 0.67 . 1232 029 533 0.15 0.70 1.11 1.80 3.10 0.14 99.81 27 МВ11 7422 0.70 13.04 1.17 427 0.19 1.13 1.00 2.02 2.75 0.69 0.08 10126 28 Н9 74.50 0.71 11.97 4.59 0.00 1.03 0.64 138 2.86 0.01 97.7 29 lOW 74.50 0.73 10.80 0.05 7.43 0.12 0.5 0.95 1.50 2.53 0.82 0.06 99.99 зо 10G 74.50 0.73 11.30 0.53 5.9 0.13 1.00 0.95 1.62 2.53 0.64 0.02 99.85 31 8 74.56 0.65 10.62 0.65 5.45 0.12 120 0.95 1.87 2.86 0.70 0.06 99.69 32 D-5D 74.58 а.66 11.81 · 039 4.75 0.15 1.00 0.91 1.75 2.93 0.50 0.15 99.58 33 20-2 74:60 0.60 11.50 032 428 0.09 0.86 1.09 1.87 2.81 0.72 0.11 98.85 34 31ZH 74.60 0.71 1131 1.47 4.17 0.08 1.02 1.14 1.71 3.00 0.12 0.18 99.51 35 12S 74.70 0.65 1220 0.83 4.02 0.12 0.9 0.76 1.80 2.75 0.45 0.14 9932 36 2а 74.80 0.57 11.30 236 I 3.51 0.09 0.95 . 0.61 2.14 323 038 0.00 99.94 37 22А 74.80 0.66 11.48 0.13 520 0.12 12 0.98 1.9.5 3.10 . 0.13 99.75 38 7-6 74.83 0.75 13.00 025 4.46 0.09 0.84 0.96 1.71 233 027 0.10 99.59 39 23А 74.88 0.68 1221 0.72 4.42 0.11 1.00 0.77 1.80 3.00 0.10 0.11 99.8 40 M13G 74.88 0.41 11.74 3.99 0.00 0.77 0.69 1.42 2.66 0.00 96.56 41 10Е-Е 74.90 0.67 12.30 0.72 3.88 0.10 0.82 0.66 1.70 2.50 0.43 0.09 98.77 42 6-2 75.02 . 0.65 11.47 0.30 4.87 0.10 0.85 122 1.85 3.10 0.53 022 100.18 43 7-4 75.17 0.75 12.40 0.69 3.88 0.09 0.70 0.91 1.75 2.45 0.55 0.10 99.44 44 19-3 75.20 0.66 11.14 1.02 5.00 0.11 0.90 0.84 1.75 2.73 0.07 0.13 99.55 45 USN6014 75.30 0.00 11.10 3.96 0.00 0.75 0.59 1.97 2.71 0.00 9638 46 MD5 7535 0.66 12.46 2.49 236 0.16 0.97 0.61 1.41 3.03 0.40 0.06 99.96 47 М22 0\ 76.40 0.66 12.50 0.85 4.05 0.12 0.6 02 1.72 2.79 0.10 0.01 100.00 \о 48 31Е 75.50 0.65 10.98 0.83 4.30 0.06 1.12 0.99 1.79 3.00 0.12 0.16 99.5 49 31Z 75.56 0.66 10.63 0.86 5.00 0.08 0.92 0.99 1.64 2.90 0.59 0.17 100.00 · 50 458 75.57 0:65 10.69 0.46 5.08 0.07 0.92 0:85 1.94 2.96 .0.56 0.16 99.91 51 2ZH 75.60 0.55 11.50. · 0.05 4.10 0.09 0.84 1.10 1.89 2.91 0.44 021 9928 52 12-3 75.67 0.60 1120 0.10 531 0.11 0.8 0.80 1.82 2.52 0.45 0.12 99.5 53 37-Р 75.76 0.42 9.52 1.63 520 0.09 0.51 128 1.74 2.64 0.42 0.18 9939 54 23W 76.00 0.60 11.81 0.52 4.00 0.12 1.00 0.84 1.80 2.87 0.44 0.12 100.12 55 2-5 76.15 0.50 1120 0.15 3.92 0.08 0.80 0.91 2.00 2.91 0.52 0.14 99.28 56 2А 76.17 0.60 . 12.10 020 4.02 0.09 0.70 ·0.80 1.89 3.00 0.49 0.18 10024 57 7-3 76.30 0.55 11.75 0.14 438 0.14 0.81 0.87 1.86 2.81 0.49 0.12 10022 58 USN6015 76.40 0.00 1120 4.65 0.00 0.91 ·0.60 1.87 2.56 0.00 98.19 59 20w 76.42 0.56 10.13 124 4.01 0.12 0.9 0.77 1.80 3.00 0.44 0.10 99.49 60 31А 76.48 0.56 10.72 0.59 4.46 0.05 0.82 0.85 1.86 3.07 0.02 0.14 99.62 61 К1820. 76.50 0.65 12.50 4.67 0.01 0.90 0.66 1.14 3.06 · 0.01 100.11 - · 62 20 1 76.60 0.55 10.50 027 4.17 0.08 0.76 0.76 1.90 2.81 0.40 . 0.09 98.89 63 12-2 76.60 0.58 10.50 0.45 4.06 0.09 0.8 0.74 1.87 2.75 033 0.10 98.87 64 М8В-1 76.72 0.51 10.90 331 0.09 0;62 0.79 1.61 339 0.01 97.97 65 10-2 76.90 0.50 10.40 0.63 3.88 0.09 0.71 0.56 1.83 2.75 0.35 0.09 98.69 TaЫ� 9 (end)

2 3 4 5 · 6 7 8 9 10 11 12 13 14 15

66 МDб 76.93 0.61 11.12 1.82 2.79 0.14 0.75 0.62 i.62 2.93 0.55 0.06 · 99.94 67 22-3 77.06 0.60 11.00 0.07 4.17 0.08 0.76 · 0.87 1.96 3.00 0.44. 0.11 100.12 68 М-1О 7730 0.64 11.50 0.80 3.78 0.11 0.55 03 1.88' .3.03 0.1· 0.00 99.99 69 1ОЕ-1 77.40 0.56 10.40 0.66 4.02 0.09 0.71 0.54 1.83 2.75 . 0.15 0.09 992 70 2-4 77.6 0.50 10.70 0.12 3.77 0.07 0.7 0.73 1.96 2.90 0.40 0.10 99.55 71 М20Р 78.03 0.57 926 0.48 3.98 0.13 0.71 0.61 1.7 2.79 0.90 0.00 99.16 72 М-35 7820 0.61 10.50 0.85 3.74 0.09 0.45 0.85 1.64 2.83 0.16 0.10 100.02 73 BS37P 7838 0.56 9.97 0.68 3.09 0.19 0.54 0.46 1.52 2.66 1.13 0.13 9931 74 М9А-1 79.14 0.48 9.66 2.73 0.13 0.58 123 1.64 2.93 0.02 98.55 75 М9А-2 8032 0.47 7.84 3.42 0.16 0.47 035 1.43 2.72 0.01 97.19 76 3IA-1 80.44 0.43 8.70 3.04 0.18 0.65 0:42 1.68 2.88 0.00 98.44 77 4ОВ 80.52 032 8.66 3.92 О 0.48 0.5 1.5 2.95 0.01 98.86 78 МЗ3 81.46 . 0.49 8.60 3.08 0.06 0.46 024 1.46 3.00 0.02 98.89 79 М41 82.60 0.43 7.70 0.78 3.08 0.11 035 0.4 1.61 . 2.77 0.10 0.00 99.93 ...J 80 М28 83.00 0.43 8.15 035 2.93 0.09 03 0.05 1.71 2.78 033 ' 0.01 100.13 с 81 М37 83.50 0.42· 735 0.75 32 0.1 03 02 1.6 . 2.54 0,13 0.02 100.11 82 К4/6 . 74.61 0.67 14.40 4.69 0.12 0.98 0.62 1.14 3.09 0.00 10034 83 К4/5 . 76.53 0.65 12.49 4.67 0.13 0.9 0.66 1.14 3.06 0.01 10025 84 К4/9 78.92 0.57 10.78 3.64 0.12 0.64 0.61 1.17 324 0.02 99.73 85 К4/1 79.79 0.47 10.75 3.45 0.17 0.6 0.53 1.00 325 0.00 100.01 86 К4/7 8034 0.51 10.68 337 0.11 0.63 0.53 1.00 32З 0.01 100.42 87 К4/8 80.74 0.58 10.16 329 0.08 0.56 0.53 1.10 324 0.00 1OQ3 88 К4/1О 81.58 0.48 9.56 3.11 0.12 0.57 0.53 0.97 3.06 0.02 100.01 89 К4/2 81.60 037 9.42 325 0.08 0.56 0.56 · 1.07 3.10 0.00 100.01 90 К4/4 81.72 0.53 9.47 332 0.06 0.56 ·0.45 0.96 2.94 0.02 100.05 91 К4/3 . 81.83 0.44 8.70 337 0.08 0.54 0.59 122 3.09. 0.01 99.88 АУЕ 75.83 0.60 1135 0.76 425 0.11 0.84 0.94 1.62 2.83 030 ' 0.08 VAR 9.11 0.02 2.76 031 0.89 0.00 0.07 0.62 0.09 0.07 0.16 0.01 STD 3.02 0.15 1.66 0.55 0.94 0.05 027 0.79 030 · 026 0.40 0.11

## 25, 26, 29, 39, 41, 55: layered bIack glasswith lenses of whitish dence pumice; ## 9, 19, 51: black glass with the bIue veinlets; # 24: separated bIue glass (Zolensky and Koeberl, 1991);## 34,49, 52: la ered bIack Iass with large voids, ## 79-88:microprobe rofile of the acid Zhamanshinite (Koeberl et al., 1985). ## 8, 10, 73 from [JВou�ka et а� � 1981). ## 45, S8 from (КоеЬеrl and FreSc eriksson, 1986). ТаЫе 10 Zhamanshin impact crater: tektites-irghizites . N Sp.# Si02 Тi02 АI2Оз F�Оз FeO MnO MgO СаО Na20 К2О Li Р205 Surn 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

1 11-6 69.00· 0.87 10.46 139. 7.06 0.15 . 4.00 2.71 137 1.82 0.77 0.04 99.64 . 2 В3 69.06 0.96 12.61 2.74 Ц9 0.10 2.67 226 1.75 1.90 2.59 020 100.03 3 11-5 69.40 0.80 10.46 129 7.85 0.15 320 2.17 137 2.13 0.86 0.05 99.73 4 М1 70.30 0.80 11.50 2.90 4.50 0.12 2.90 3.50 1.68 1.64 0.10 0.00 99.94 5 В2 7034 0.83 11.75 233 4.88 0.15 3.10 331 1.75 1.83 0.00 0.14 100.41

" 6 111-6 7035 0.81 8.72 13.41 0.12 2.04 1.71 1.05 1.95 0.94 0.03 101.13 ..... 7 в4 7036 0.77 1121 2.44 4.84 0.18 3.40 3.02 1.67 1.83 0.00 0.11 99.86 8 114 70.48 0.90 9.62 137 6.85 0.13 5.56 iJ.95 1.00 1.82 0.93 0.03 99.64 9 МВТ22 71.� 0.74 10.78 1.46 4.98 0.17 3.14 2.68 139 1.93 1.57 0.01 100.53 10 11-3 71.70 0.90 1026 1.65 6.44 0.15 2.90 2.03 1.12 2.00 0.71 0.05 99.91 11 11-2 71.76 0.90 10.46 0.41 7.72 0.15 . 2.40 1.50 125 2.13 · 0.84 0.11 99.63 12 Т 72.01 0.78 15.55 5.55 0.01 1.11 0.55 1.10 2.83 0.01 99.50 13 F 72.03 0.85 10.13 6.50 0.02 3.75 258 1.00 1.58 1>.02 98.46 14 F 72.15 0.82 9.77 6.48 0.01 3.59 2.80 . 0.96 1.62 . 0.00 9821 15 В5 72.44 0.70 10.72 1.80 5.16 0.18 3.40 2.87 133 1.83 0.00 0.10 100.53 16 ВS2 72.55 0.84 9.70 2.57 3.89 022 2.98 228 1.02 1.92 1.61 0.07 99.65 17 11-С 72.70 0.78 9.90 1.89 428 ,().10 324 2.73 1.17 1.86 0.40 0.03 99.08 18 ВS1 72.87 0.91 1020 2.15 3.68 0.19 2.64 234 1.30 . 1.90 0.94 0.09 9921 19 F/1 72.95 0.69 9.72 621 0.01 · 3.18 2.41 1.15 2.01 0.03 9837 ТаЫе Ю 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 20 F/2 73.00 0.79 9.82 6.06 0.02 320 2.68 1.06 .1.83 0.02 98.50 21 F/3 73.11 0.84 9.92 637 0.01 3.50 2.85 0.99 1:66 ОЛl 9927 22 Т/1 7332 0.78 9.99 6.49 0.00 3.69 2.43 0.85 1.97 0.00 9952 23 МВТ21 7333 0.78 10.92 1.87 4.68 0.16 2.56 2.67 1.17 1.95 0.47 0.01 100.57 24 МВТ8 7333 0.78 1038 1.10 4.98 0.15 2.95 228 123 1.96 1.44 0.02 100.60 25 F/4 7351 0.82 1021 522 · 0.01 2.57 2.55 1.16 2.11 0.05 9822 26 F/5 7359 0.82 1021 5.53 0.02 2.60 2.48 1.13 2.14 0.02 98.56 27 F/6 73.61 0.82 1023 5.53 0.01 2.60 2.48 1.13 2.14 0.02 9858 28 Мl1-8 73.62 0.80 9.77 5.69 0.05 2.% 2.48 0.91 . 1.87 0.02 98.19 29 111-8 73.61 0.80 8.80 953 0.12 2.05 1.72 0.9j 1.99 0.64 0.03 10024 30 Т/2 73.80 0.78 10.07 6.04 0.00 331 239 0:76 1.98 0.00 99.13 31 111-1 73.80 0.81 8.84 9.15 0.10 2.11 1.77 0.90 1.% 0.70 0.03 100.17 32 Fj7 73.91 0.93 1030 5.46 0.02 2.72 2.60 1.09 2.06 0.08 99.19 -..j N 33 в6 73.94 057 1152 1.49 3.75 0.10 139 129 1.82 2.67 0.43 026 9923 34 Т/3 74.01 0.93 9.91 5.13 0.00 2.41 2.40 122 1.% 0.02 97.99 35 F/8 74.01 0.85 1035 5.46 0.01 2.70 2.58 1.10 2.08 0.05 9920 36 Мl1-8/1 74.04 0.73 9.60 5.40 0.06 2.94 2.46 1.10 1.83 0.02 9820 37 МВТ24 74.06 0.77 1023 1.79 3.98 0.13 2.82 223 124 1.94 1.00 0.00 100.19 38 F/9 74.06 0.97 9.64 558 0.01 2.70 235 1.04 1.88 0.01 9825 39 F/1O 74.12 0.72 9.78 531 0.02 2.70 2.43 1.14 2.09 0.00 9833 40 F/11 74.12 0.83 9.67 5.48 0.01 2.74 2.42 1.15 1.97 0.01 98.41 41 F/12 74.16 0.76 10.45 5.16 0.02 2.64 232 1.09 1.98 0.02 98.62 42 F/13 74.17 0.81 1024 5.54 0.01 2.87 2.45 1.15 1.91 0.02 . 99.18 43 МВ1 74.19 055 9.70 1.97 3.68 0.12 325 2.08 1.61 1.42 1.06 0.15 99.78 44 111-5 74.19 0.81 8.97 838 0.11 2.06 1.77 1.14 1.92 038 0.03 99.76 45 F/14 7423 0.86 10.44 5.47 0.02 2.72 2.62 1.12 2.12 0.05 99.67 46 F/15 7424 0.78 1024 552 0.01 2.65 2.70 1.09 1.99 0.04 9927 47 F/16 7428 0.84 9.79 5.43 0.00 2.66 225 1.03 2.02 0.00 9830 48 Т/4 7428 0.78 10.16 5.60 0.01 2.93 236 0.97 0.00 0.00 97.10 49 F/17 7432 0.80 10.09 536 0;02 2.68 2.44 1.09 2.03 0.02 98.87 50 F/18 7434 0.77 1022 " 522 0.01 'f.47 2.63 1.19 2.03 0.07 98.96 51 11-1 7434 0.82 11.47 023 536 0.12 130 0.95 1.87 2.80 0.62 0.18 100.06 52 F/19 7435 0.80 1022 5.48 0.01 2.79 2.50 " 1.11 2.01 0.02 9930 53 зо 74.40 0.82 10.50 1.82 421 0.10 2.64 2.74 1.25 1.86 0.00 0.12 100.46 54 F/20 74.42 0.82 10.00 5.43 0.01 2.68 2.41 1.10 1.98 0.03 98.89 " 55 F/21 74.44 0.88 10.03 5.47 0.02 2.76 235 1.05 1.88 0.02 98.92 56 F/22 74.51 0.78 10.43 5.41 0.01 2.76 2.57 1.08 2.00 0.07 99.63 57 111-6/1 74.53 0-.81 8.98 8.50 0.13 1.87 1.67 0.73 1.93 " 034 0.03 99.52 58 F/23 74.60 0.69 1023 5.49 0.01 2.84 2.49 1.09 1.90 0.01 9936 59 F/24 74.66 0.76 9.98 5.46 0.00 2.66 230 1.06 2.05 0.00 98.93 60 F/25 74.76 0.87 " 10.19 5.68 0.01 2.79 2.52 1.12 1.83 0.00 99.78 61 11А 74.90 0.85 11.98 1.05 4.62 0.13 1.05 0.47 1.68 2.60 0.50 0.07 99.90 -.) w 62 F/26 74.91 0.81 10.40 5.57 0.02 2.76 2.42 1.08 2.02 0.04 100.05 63 111/2 75.29 0.79- 9.06 6.74 0.09 2.08 1.71 1.01 1.91 0.24 0.03 98.95 64 F/27 75.55 0.88 10.47 5.51 0.00 2.71 2.63 1.18 2.03 0.02 100.98 65 111/9 75.72 0.83 932 636 0.08 2.01 1.92 0.85 1.93 0.16 0.03 9921 66 111/7 75.81 0.81 9.03 6.53 0.09 226 1.81 0.93 1.99 0.02 О.оз 9931 67 111/18 75.84 0.80 9.15 635 0.08 227 1.81 0,85 2.01 0.16 0.03 " 9935 68 М2 76.50 0.82 9.00 220 4.05 0.11 230 i.9O 120 1.78 0.10 0.00 99.96 69 F/28 77.14 0.82 9.45 424 0.01 2.16 1.75 1.04 2.10 0.04 98.76 AVE 73.49 0.81 1020 1.74 5.74 0.07 2.73 227 1.16 1.95 030 0.04 VAR 2.80 0.01 0.97 0.43 234 0.00 0.44 030 0.06 0.11 025 0.00 STD � 1.67 0.07 0.98 0.66 1.53 0.06 0.66 0.55 024 033 0.50 0.05

Analyses noted Ьу letters belong (о: P.Florensky (F), �ostly unpublished; Ja.Boiko (В), unpublished; Taylor and Мс Lennan, 1979 (Т); Bou�ka et al, 1981 (Bs). ТаЫе 11 Zhamanshin impact crater: microtektites from the crater rim sunace deposits

Sp.# Si02 Тi02 А1zOз FezОз FЮ MgO ' СаО Na20 К2О Sum 1 59.10 0.61 10.00 12.50 7.80 520 1.40 1.50 98.12 2 65.50 0.68 8.18 10.80 7.00 2.08 0.79 134 96.42 3 66.80 0.65 8.09 10.30 626 1.43 0.90 1.51 95.97. 4 6920 0.64 11.00 7.63 4.11 238 1.02 2.03 98.06 5 70.00 0.67 10.50 7.50 4.00 2.10 1.10 2.00 97.91 6 72.10 0.63 9.14 8.95 4.75 1.10 1.00 1.75 99.44 7 72.50 0.70 8.50 8.30 5.10 1.00 0.90 1.50 98.53 8 73.70 0.75 9.55 620 333 236 1.00 1.90 98.83 9 73.90 0.63 8.05 820 5.00 1.05 1.00 1.50 9936 10 61.50 0.62 12.60 11.60 6.60 1.90 1.80 - 2.40 99.06 11 61.80 0.59 12.00 12.30 8.69 227 1.58 1.07 10033 12 -...1 62.30 0.60 13.10 6.94 523 3.40 2.01 1.74 9536 "'" 13 62.50 0.62 12.70 10.90 638 2.79 1.82 1.59 9932 14 62.50 0.59 13.00 10.30 5.44 3.01 1.57 1.62 98.09 15 63.10 0.62 1320 10.30 5.40 320 1.55 1.75 99.14 16 64.40 0.65 13.50 927 4.87 1.99 2.15 2.01 98.89 17 65.00 0.70 16.30 720 320 3.70 1.52 1.90 99.56 18 65.40 0.75 16.60 7.18 3.44 2.92 1.61 1.81 99.74 19 65.40 0.64 14.60 720 3.30 4.50 1.65 2.10 99.42 20 67.90 0.81 15.60 8.12 3.94 1.74 2.18 1.98 10231 21 68.50 0.62 13.10 534 221 4.50 1.69 1.93 97.92 22 68.50 0.59 1220 5.80 225 7.10 123 1.70 9939 23 71.30 0.58 12.80 5.13 2.19 5.54 1.58 1.84 - 101.00 24 71.50 0.83 15.00 537 2.57 1.05 1.95 1.91 10021 25 72.10 0.58 12.40 5.03 2.11 6.79 122 1.62 101.91 26 74.70 0.56 11.90 3.88 129 2.84 1.84 239 99.42 27 - 61.50 0.67 15.90 9.95 431 2.67 1.90 1.93 98.86 28 64.90 0.68 12.10 8.70 4.85 3.90 1.02 1.60 97.77 29 73.60 0.79 9.94 5.09 3.10 2.55 2.04 126 98.43 3D 7420 0.75 9.85 535 325 220 125 2.05 98.92 31 74.60 0.72 9.68 6.71 4.43 1.58 131 1.02 100.08 ·32 75.10 0.76 9.75 6.18 339 2.81 1.03 1.75 100.80 33 7730 0.69 9.40 4.40 230 1.95 0.95 1.95 98.99 34 77.40 0.78 930 4.45 225 1.70 0.95 2.00 98.87 35 79.10 0.69 9.10 415 230 1.78 0.75 1.85 99.86 36 64.10 0.81 16.60 7.59 3.41 0.81 131 2.79 97.45 37 65.50 0.73 1220 8.95 4.81 0.86 1.12 1.89 96.10 38 66.40 0.83 14.40 6.93 3.65 1.49 1.41 2.82 97.95 39 67.90 0.71 10.90 6.69. 3.76 1.68 ' 1.58 2.63 95.91 , 40 68.00 0.62 11.50 8.71 4.43 0.74 1.17 1.92 97.12 41 68.10 0.66 12.90 7.56 3.50 1.02 1.16 228 9722 42 69.50 0.56 11.10 9.41 ' 436 0.75 1.02 1.98 98.71 43 69.60 0.65 11.40 8.79 433 0.66 1.07 1.89 98.43 44 7020 0.59 11.10 8.51 429 0.67 1.15 1.90 98.44 45 ' 76.00 0.45 820 5.93 3.00 0.43 1.15 2.60 67.79 46 84.40 026 4.63 423 1.80 028 0.58 0.87 97.09 .....:а 47 89.70 022 4.03 2.09 0.90 034 0.55 1.18 99.06 v\ 48 94.10 0.12 '1.97 1.80 0.75 0.13 031 0.67 99.89 49 9930 0.03 0.00 033 0.02 0.01 0.06 0.09 99.88 50 99.90 0.00 0.00 0.17 0.00 0.00 0.02 0.05 100.16 51 63.50 0.68 12.60 1120 6.71 1.96 1.64 1.65 99.98 52 69.70 0.53 11.80 5.52 , 223 420 1.62 2.16 97.78, 53 70.00 0.84 15.00 5.65 2.50 0.99 1.89 2.03 98.93 54 70.50 0.62 9.90 '7.74 4.12 0.83 235 2.77 98.85 АУЕ 70.47 0.62 10.90 7.13 3.80' 2.17 130 1.78' VAR 86.47 0.03 1323 7.62 330 2.59 026 031 SТD 930 0.18 3.64 ,2.76 1.82 1.61 0.51 0.55

After Glasset аl (1983), thousands of glass microsph�ruies and rare drops, discs,etc llamed 115" microirghizites" were sieved from 119 g sample of а stream de it from tht irghizite strewn deposit at SW 'part of the crater rim. ## 1-7 (type1): black opaque spheruies; ## 8-24 �� 1): tran5parent yellQw-grееп s herules; ## 25-33 (type Ш): vesicular transparent brown spheruies; ## 34-48 (typeIV : ighly vesicular, heterogeneous spE erules ; # 49-54:others. ТаЫе 12 Zhamanshin im act crater: microtektites from the crater rim surface ап lfrom the deep bore holes # 102 and 103

N Sp.# Si02 Тi02 Аl2Оз FezОз FeO МпО MgO СаО Na20 К2О Sum 1 М19 62.58 0.67 12.79 10.47 0.10 4.91 3.43 2.02 1.61 98.59 2 М15 63.98 0.53 13.82 8.36 0.01 3.49 3.03 1.74 1.72 96.71 3 М31 64.10 0.74 1235 8.80 0.00 4.86 3.16 1.69 1,53 9726 4 М16 64.17 0.82 16.06 6.76 0.17 3.56 2.44 1.91 1.86 97.76 5 М29 66.85 0.99 14.58 6.50 0.00 3.09 128 1.74 1.98 97.03 6 М13/3 68.62 0.56 9.14 9.82 0.01 4.93 0.80 0.94 1.69 %.52 7 М28 69.04 0.64 1239 7.51 0.00 3.07 0.80 126 1.84 96.58 8 М13/1 69.09 0.65 8.65 10.11 0.02 4.88 [21 1.00 1.49 97.13 9 М13/2 69.95 0.63 10.80 8.54 0.01 3.81 0.75 0.91 1.52 96.93 10 М18 70.00 0.69 10.46 6.69 0.02 3.47 227 125 1.04 95.91 11 М13/5 70.00 0.73 10.47 8.06 026 4.03 0.85 138 1.89 97.71 1.65 97.76 -..1 12 М13/4 70.10 0.60 8.40 9.88 021 4.93 1.13 0.85 0\ 13 М25 71.45 0.74 9.23 7.00 0.18 3.54 2.36 1.05 1.60 97.15 14 М23 7220 0.77 8.71 7.18 0.00 335 2.65 0.74 1.89 97.52 15 М27 74.59 0.47 7.47 7.30 0.15 3.65 1.06 1.04 1.63 97.36 16 102-1 59.88 0.63 1338 11.09 0.10 5.78 3.56 1.55 1.44 97.41 17 102-2 6027 0.67 14.97 10.11 0.01 4.67 3.15 1.80 1.52 9720 18 102-3 61.09 0.01 13.11 12.15 0.44 533 2.95 1.93 1.59 98.63 19 102-4 61.55 0.93 1432 9.17 0.02 3.84 3.64 1.61 1.98 97.08 20 102-5 6533 0.78 12.73 6.74 0.12 3.01 522 1.71 1.72 9739 21 .102-6 65.91 0.60 8.30 11.77 0.11 6.18 1.83 1.13 1.42 97.26 22 102-7 67.70 0.56 7.06 10.54 0.14 5.64 . 2.94 0.87 1.51 97.00 23 102-8 6828 0.87 931 10.64 0.16 4.56 0.76 1.18 1.70 97.49 24 102-9 68.64 0.74 12.64 7.43 0.08 2.96 2.08 1.40 1.85 97.85 25 102-10 70.41 0.46 11.77 4.53 0.00 1.63 522 1.61 1.92 97.55 26 102-11 71.06 0.71 11.61 7.41 0.01 2.99 0.56 1.06 2.18 97.62 27 102-12 72.78 0.80 10.78 4.79 0.15 2.65 2.08 133 1.93 9732 28 102-13 73.55 0.76 9.47 6.53 0.01 2.81 1.63 1.03 1.96 97.76 29 102-14 74.01 0.98 9.80 5.90 0.00 2.46 1.74 1.05 0.02 95.97 30 103 76.15 0.81 8.51 4.94 0.09 1.47 1.92 0.82 2.10 96.81 31 102-15 76.44 0.65 9.72 3.90 025 2.10 1.60 0.75 1.89 9732 АУЕ 6838 0.68 11.06 8.08 0.09 3.80 220 130 1.67 VAR 20.45 0.03 5.53 4.64 0.01 1.40' 1.47 0.14 0.14 STD 4.52 0.18 235 2.15 0.10 1.18 121 038 038

АВ data were placed at our disposalЬу V.Masaitis(microprobe analyses). ## 1-15: from the surface;## 16-31: from the boreholes.

ТаЫе 13

Basic Zhamanshinites: melted impactite bombs

-.J -.J . N Sp.# Si02 · Тi02 Аl20з FezОз FeO МNO MgO СаО Na20 К2О и. Р205 Sum 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

1 �1a 49.94 0.95 19.91 7.59 3.52 ·0.13 3.03 7.77 3.87 130 1.02 022 9925 2 41d 51.15 0.90 19.77 6.70 2.42 0.15 335 7:07 4.00 127 1.07 ·029 91Ц4 3 42Ь 51.15 0.90 19.24 6.44 4.90 0.14 233 8.48 3.65 127 0.83 022 99.55 4 12а 5138 0.95 17.72 2.90 6.60 0.19 4.90 6.92 335 129 3.35 022 99.77 5 41Ь 51.44 1.00 19.19 8.98 1.81 0.13 3.03 7.65 3.81 130 0.86 028 99.48 6 41zh 51.51 0.94 19.75 6.84 323 0.14 3.03 7.91 3.88 127 0.75 021 99.46 7 41g 51.51 0.90 19.91 6.99 3.03 0.13 325 8.48 329 123 0.10 0.77 99.59 8. 43а-1 51.65 0.68 20.14 7.68 0.03 2.96 10.65 3.03 1.02 0.00 0.00 97.84 9 41g-1 5225 0.95 19.58 731 2.42 0.13 3.03 835 3.44 133 0.50 021 99.50 ТаЫе 13 (conti�.) 1 2 3 4 5 6 .7 8 9 10 11 12 13 14 15

10. 33а-2 5237

61 31i-l 57.46 0.80 18.06 2.48 5.06 0.10 3.17 625 429 137 0.18 026 99.48 62 3Зе 58.10 0.68 17.54 3.62 3.88 0.11 3.36 639 3.55 1.60 0.75 021 99.79 63 33z-1 58.11 0.60 17.97 5.43 0.01 2.94 6.78 4.72 1.43 98.02 64 33zh-l 58.16 0.61 16.19 2.07 735 0.10 3.16 625 3.55 120 0.92 021 99.77 65 33т 58.64 0.66 1737 0.50 6.69 0.10 3.46 6.10 4.50 1.18 0.73 021 100.14 66 45а-5 58.84 0.78 17.12 6.42 0.02 3.71 727 4.13 135 0.00 99.66 67 59.10 0.95 18.90 3.88 425 0.16 2.10 5.43 229 1.71 0.92 028 99.97 00 с> 68 33а-3 59.36 0.63 17.71 233 7.70 0.08 3.16 5.68 �.62 133 . 0.52 022 10334 69 33z-2 59.41 0.64 17.12 5.55 0.00 2.87 6.13 4.62 1.59 97.93 70 33z-3 60.57 0.66 17.04 6.02 0.02 2.95 6.79 4.52 122 99.82

АУЕ 54.68 0.82 18.88 4.78 5.18 0.12 3.04 735 3.78 1.36 0.65 0.17 VAR 5.41 0.02 129 3.81 3.42 0.00 027 1.52 0.55 0.08 0.41 0.02 STD 233 0.13 1.14 1.95 1.85 0.07 0.52 123 0.74 028 0.64 0.13

, . ## 1, 2-4, 10, 13, 19-20, 26, 28-36, 39-40, 42, 46-49, 51, 53, 60-62,65, 67-68:replete of target rock inclusions (generally of diaplectites). Other specimens have rare or smaH such inclusions. ##·34 and 52: from (Вou�aet al. 1981). ТаЫе 14 Basic Zhamanshinites: small well shaped drops

N Sp.# . Si02 Тi02 дl2Оз . FezОз FeO МпО MgO СаО . Na20 . К2О L.i. Р205 Sum

1 F 52.42 . 0.82 20.54 7.87 (}.ОО 2.66 9.06 3.74 132 021 98.64 2 МD11 52.74 0.77 18.87 7.94 0.72 0.17 2.80 9.87 2.91 126 1.62 0.16 99.83 ·3 MD10 53.22 0.85 19.51 8.14 .0.86 025 2.87 6.98 4.09 1.06. 1.94 0.17 9994 4 F 53.42 0.85 20.49 7.76 0.01 2.76 8.46 4.44 137 0.17 99.74 5 F 53.47 0.96 20.69 8.08 0.02 2.81 .836 4.45 1.23 023 10032 6 F 53.56 0.84 20.59 7.88 0.00 2.71 8.59 3.86 133 0.14 99.50 7 F 53.79 0:79 20.07 7:68 0.00 2.74 8.91 3.48 1.42 0.00 98.90 8 F: 54.06 0.82 19.65 7.64 0.02 2.62 8.94 3.85 133 0.17 99.12 9 F 54.10 0.94 20.64 7.96 · 0.01 2.67 8.83 3.99 . 131 025 100.71 10 F 54.17 1.07 · 20.00 7.80 0.02 2.74 8.93 3.83 1.47 024 10029 11 F 5422 .0.98 19.21 7.78 0.00 2.69 8.98 3.72 137 024 99.19 12 F 5431 0.77 20 52 7.83 0.02 2.71 9.06 3.69 1.43 025 100.61 00 . >-' 13 F 54.43 1.06 20.09 7.86 0.00 2.70 9.07 3.74 132 023 100.51 14 F 54.52 1.09· 20.72 7.94 0.00 2.48 . 9.07 3.89 128 023 10123 15 F 54.53 0.73 21.82 6.67 0.01 1.82 8.65 422 122 0.19 99.87 16 F 54.79 0.79 2124 7,53 0.19 2.62 838 4.12 133 022 10121 17 F 54.80 0.86 20.74 8.00 0.01 2.72 · 8.24 4.40 129 024 10131 18 11-9 54.83 0.80 1930 5.42 3.50 0.16 2.40 8.11 330 1.81 030 010 100.13 19 F 54.95 0.80 19.76 7.03 0.00 2.89 8.11 3.76 . 1.57 025 . 99.12 20 11-8 54.96 0.95 17.89 2.19 8.75 0.19 3.00 5.56 3.75 1.59 0.96 0.16 99.95 21 ·F 55.07 1.04 18.90 8.15 0.00 2.94 823 437 122 024 100.16 22 F 55.84 0.83 19.76 6.93 0.00 3.00 8.01 3.74 1.68 025 100.06 23 F 56.73 а.77 19.61 6.88 0.01 3.12 7.91 3.72 1.75 024 100.75

ДУЕ ' 5430 0.88 20.03 5.92 6.92 0.05 2.72 8.45 . 3.87 139 022 020 YAR 0.88 0.01 0.72 · 5.79 4.51 0.01 0.06 0.70 0.13 0.03 027 0.00 STD 0.94 0.11 0.85 2.41 2.12 0.08 025 0.83 . 036 0.18 0.52· 0.06

F: small (0.5-2 сm) teardrops, spheres, etc. named as "basic irghizites" (Florensky and Dabizha, 1980). # 2, 3 belong·to Y.Masaitis, # 18 and 20 - to E.Izokh. ТаЫе 15 Fragments оС basic melted impactites from the deep bore holes

N Sp.# Si02 . Тi02 А12Оз Fе20з FeO МпО MgO СаО Na20 · . К2О и: Р205 ,Sum

1 М1 5124 1.00 19.77 7.50 0.10 3.48 731 525 1.17 96.84 2 М7 5125 0.71 20.30 7.53 0.19 2.86 822 420 1.51 96.77 3 М1 52.03 0.88 19.84 733 0.00 2.00 921 3.46 122 96.00 4 М1 52.10 0.65 18.92 6.78 0.00 3.52 9.13 4.09 1.40 96.61 5 М1 5222 0.68 18.80 7.46 020 3.45 9.10 3.53 129 96.75 6 М2 52.74 0.85 18.97 838 0.15 2.40 7.94 4.54 126 9723 7 М1 53.42 0.80 17.30 11.16 032 326 6.97 3.87 1.05 98.18 М1 2.85 7.14 535 1.40 96.90 00 8 54.65 0.49 18.90 6.08 0.01 N 9 М3 55.80 0.69 17.70 6.52 038 3.41 6.91 4.33 129 97.05 10 М1 57.09 0.90 1720 6.50 0.00 238 739 429 1.58 9737 11 М1 5734 0.62 1727 6.46 021 2.06 6.71 5.12 1.30 97.09 12 М1 58.62 0.53 17.07 6.58 0.01 235 7.10 4.17 126 97.71 13 М1 59.30 0.67 16.67 5.53 039 3.06 6.77 3.48 135 9724

АУЕ 54.45 0.73 1836 722 0.15 2.85 7.68 428 131 VAR 7.61 0.02 136 1.80 0.02 029 0.81 038 0.02 SТD 2.76 0.14 1.17 134 0.14 0.54 0.90 0.62 0.13 ·

АН data belongto V.Masaitis and A.Raichlin. ТаЫе 16 Basic Zhamanshinites-im(!ac tites: vesicular slaBs and (!u mices N Sp.# Si02 Тi02 АI2Оз FezОз FeO MnO MgO СаО Na20 К2О L.i. Р205 Sum 1 26G-3 50.36 0.97 18.55 7.00 322 0.13 3.17 8.09 3.75 1.40 2.43 027 99.34 226D 51.12 0.94 20.56 7.53 1.94 0.15 2.84 8.52 3.50 127 1.43 028 100.08 3 18-2 1.73 0.80 19.30 4.17 3.63 0.13 . 1.94 7.43 2.72 1.77 .5.11 023 98.96 4 14-2 5225 0.66 21.60 4.15 4.96 0.17 2.30 7.19 2.88 ·127 1.95 020 99.58 533N-2 5238 0.77 19.40 737 239 0.14 2.95 7.95 3.44 131 129 022 99.61 643D 52.68 0.80 20.02 5.68 3.61 0.11 1.43 9.60 2.30 124 1.76 028 99.51 7 М5А-2 52.71 0.81 18.72 7.50 135 0.15 2.79 724 432 0.86 2.81 · 0.00 9926 8 ЗOG 53.04 0.77 1920 731 2.93 0.15 3.06 625 3.65 1.56 124 0.34 99.50 931М 5320 0.84 19.41 427 3.80 0.10 3.17 6.52 3.58 1.59 2.84 022 99.54 10 M2G 53.46 0.87 17.99 4.57 3.44 Ю8 2.97 8.42 425 1.19 1.90 0.02 9926 11 39D-3A 54.00 1.00 2020 5.67 3.72 0.11 2.13 6.06 3.41 1.73 124 021 99.48 12 31L 54.00 0.90 20.09 4.86 4.01 0.11 3.06 6.67 3.56 1.76 0.58 0.30 99.90 13 М13А 5424 0.67 1826 628 0.00 5.57 729 429 0.67 0.00 9727 14 D4 5433 0.90 19.60 6.86 220 0.14 2.83 7.96 3.60 1.40 032 020 100.34 00 15 1ОВ 54.46 0.95 19.04 2.52 8.05 0.19 2.60 6.51 3.10 1.47 0.88 0.17 99.94 w 16 М15В-4 54.49 0.78 18.45 6.68 0.01 321 8.94 422 1.19 0.02 98.00 17 1ОА 54.58 0.73 . 18.06 4.98 1.73 0.12 2.40 720 2.71 0.77 6.57 0.06 99.91 18 М21М 54.64 0.94 19.54 6.30 3.14 0.13 2.49 5,47 3.62 1.86 1.48 0.02 99.63 19 14-1 55.73 1.00 20.85 4.74 4.64 0.15 2.15 5.90 3.00 · 1.62 0.50. 0.19 100.47 20 М15В-2 55.79 0.94 1926 522 022 4.05 8.17 3.55 135 0.01 98.58 21 М15В-1 55.77 0.78 18.45 7.10 0.93 0.15 2.91 739 3.91 123 0.58 0.00 9920 22 39D-1 56.02 0.95 19.19 6.14 322 0.13 233 . 537 3.03 1.77 1.49 024 99.88 23 М15В-3 56.05 0.68 1821 5.77 0.08 3.63 822 4.76 0.95 0,01 9838 24 39W-1 56.08 0.85 18.44 3.56 5.86 0.13 224 5.96 2.44 1.93 1.67 029 99.45 25 М15В-3 56.74 0.73 183 5.15 0.09 2.45 735 S.47 1.01 0.01 9732 26 M21L 56.80 0.89 1722 6.42 1.71 0;15 2.69 631 426 124 1.53 0.02 9924 27 м 13А-2 56.80 0.61 18.71 3.96 0.02 3.01 8.42 437 1.03 0.00 96.93 АУЕ 5420 0.83 19.13 5.65 3.8З 0.12 . . 2.83 727 3.62 135 1.47 0.14 VAR 3.08 0.01 0.93 2.04 2.95 0.00 0.57 1.15 0.52 0.11 228 0.01 STD 1.75 0.11 0.96 1.43 1.72 0.05 0.75 1.07 0.72 033 1.51 0.12

Difference between slags and pumices аге conventional and depends оп the de�ree of vesicularity and target rock inclusions.As an examples: ## 3, 48 represent vesicular slags; ## 9, 11, 12 represent typical pumlces. ТаЫе 17 Zhamanshin crater target rocks: Carhoniterous yolcanics and corresponding diaplectites

N Sp.# Si02 Тi02 АI2Оз FezОз FeO МпО MgO СаО Na20 К2О Lj. Р205 Sum

1 48-88 43.11 0.80 18.79 9.53 021 3.82 8.65 337 . 0.56 10.98 0.18 100.00 2 39ZH 45.55 0.85 18.18 7.77 1.11 0.13 222 9.49 2.63 1.46 1024 026 99.89 3 41М 49.00 0.95 17.71 730 2.42 0.13 3.77 424 4.92 1.08 7.87 024 99.63 4 9-1 5024 0.87 1738 629 1.52 0.16 2.40 8.66 1.75 1.11 9.44 022 100.04 5 M5W 5035 0.86 19.61 8.58 1.43 0.18 226 9.53 2.60 0.46 4.18 0.00 100.04 6 25А-2 50.82 0.90 19.92 7.02 1.61 0.11 3.42 4.97 5.82 1.43 3.18 030 99.50 7 25А-1 51.58 0.83 20.89 7.62 128 0.08 3.17 2.56 6.18 2.17 2.86 031 99.53 8 М21А 5221 0.85 1536 820 027 0.15 2.03 7.65 2.85 1.14 8.50 0.01 9922 00 � 9 F . 5320 0.64 20.60 7.14 0.59 0.11 235 6.75 ft·80 0.68 124 0.00 98.10 10 26В 55.10 0.66 15.70 5.50 122 0.Q9 230 7.53 129 1.67 8.43 0.19 .99.68 11 M8W 57.10 0.73 17.91 8.15 0.90 0.15 228 5.57 432 0.66 227 0.02 100.06 12 M4R 45.45 0.55 17.60 731 0.54 023 2.85 12.76 2.95 1.01 8.54 0.01 99.80 13 М2В3 45.65 1.50 1635 9.90 2.01 0.19 237 9.72 3.85 0.94 738 0.02 99.88 14 26а-1 48.50 0.72 19.56 6.80 1.67 0.15 3.06 10.51 . 2.70 1.47 338 026 98.78 15 39D-3B 4932 0.90 17.71 731 3.03 0.43 2.70 8.48 333 1.44 4.15 026 99.06 16 43(; 4937 0.94 19.54 6.04 2.79 0.06 3.08 7.01 336 1.54 537 030 99.40 17 М2В1 49.61 1.44 18.90 8.14 020 4.41 9.66 4.16 0.45 96.97 18 М2А1 51.69 0.83 2029 7.73 1.71 022 2.63 8.84 327 1.57 1.91 0.01 100.70 19 М5В 52.03 131 20.87 9.70 1.61 0.09 323 227 320 1.61 3.88 0.02 99.82 20 F 50.12 0.80 21.10 727 2.72 0.09 2.01 533 2.62 1.70 0.16 93.92 21 2БG-2 50.80 0.83 1822 6.47 3.18 0.14 322 7.88 3.44 1.93 2.11 027 98.49 22 43ZH . 51.16 0.96 2029 6.18 2.99 0.10 2.76 838 2.77 128 228 024 9939 23 27А 51.68 1.85 20.50 7.63 1.94 0.11 2.74 628 3.78 1.47 135 036 99.69 24 43Е 51.86 0.85 18.71 6.89 1.73 0.06 2.46 8.80 1.71 1.16 5.54 023 100.00 25 41Р 52.52 0.90 20.93 6.70 2.42 0.13 3.55 522 4.67 0.78 1.47 022 99.51 26 43Р 52.55 . 0.70 18.65 3.88 3.78 . 0.10 3.59 8.14 2.86 131 3.80 027 99.63 27 М4В 52.90 0.72 . 18.93 · 7.15 036 3.40 7.12 4.89 1.05 96.54 28 М2W 53.76 1.09 18.15 736 1.67 0.19 2.45 832 4.09 023 2.78 0.02 100.11 29 М4Вl 53.89 . 0.75 18.58 7.17 0.10 2.71 8.80 4.49 0.74 9726 30 F 54.00 1.06 2420 9.00 021 1.85 5.48 4.03 0.84 100.67 31 М4В2 54.10 0.75 18.78 6.68 0.06 2.61 8.48 · 3:79 1.67 96.95 32 М2А2 54.17 0.76 19.74 5.21 0.15 2.46 2.68 431 0.80 . 9030 33 F 5437 0.79 20.02 731 2.60 0.17 3.01 7.54 3.74 . 1.46 0.01 020 10122 34 М5А 54.92 090 17.76 734 1.19 0.81 235 6.14 3.00 · 0.92 .3.96 0.00 9929 35 М1В1 54.99 0.64 18.19 5.58 0.16 3.06 7.80 3.82 134 95.61 36 МIВ2 55.10 0.60 2033 5.72 0.02 1.51 9.94 433 0.92 98.50 37 М1В3 55.11 0.84 . 1831 6.41 0.13 327 726 3.48 131 96.12 38 43К 5524 0.75 · 19.70 6.24 1.44 0.11 225 5.96 3.85 0.85 330 027 99.96

00 39 М1В4 5536 0.77 16.94 729 0.08 3.09 7.78 3.41 1.69 96.43 v\ 40 М2В2 55.48 0.74· 20.14 4.19 0.10 2.71 8.52 4.81 0.67 9738 41 М15А 55.56 0.84 18.89 6.47 0.21 3.94 6.85 424 1.65 98.60 42 МIВ4 55.82 0.80 17.59 7.01 0.11 2.79 827 3.59 1.09 97.10 43 F 56.00 1.12 21.20 9.70 0.17 0.43 5.65 4.05 0.67 98.99 44 М8В 57.00 0.88 16.96 422 237 0.13 2.48 223 2.14 · 1.06 10.59 0.01 . 100.07 45 38Е 58.12 0.82 13.84 1.78 4.79 0.11 1.02 6.24 121 2.00 9.01 0.29 99.23

AVE 5237 0.88 18.88 7.15 323 0.16 2.71 724 3.57 1.18 334 0.12 VAR 10.94 0.06 3.20 2.75 5.06 0.01 0.53 4.90 1.11 020 12.26 0.02 STD 331 024 1.79 1.66 2.25 0.12 0.73 221 1.05 0.44 3.50 0.12

## 1-11: unaltered target rocks (mandelsteins, tuffs, tuff - lavas, tuff-breccia); ## 1-9: the same, rich in calcite; ## 12-45: diaplectites with initial structure partially от completely preserved; ## 20, 30, 33, 43: diaplectites named as "burned clays" Ьу (Florensky and Dabizha, 1980). ТаЫе 18 Zhamanshin crater target rocks: silurian ultrabasit.es, yolcanics and сопеsропdiпg diaplectites

N Sp.# Si02 Тi02 А12Оз F�Оз FeO МNO MgO СаО Na20 К2О Li P:z05 Sum 1 17-1 29.69 0:04 0.42 1.36 4.87 0.12 33.05 0.42 0.05 0.10 2937 0.05 9954 2 17-2 2552 0.11 7.43 . 5.82 5.08 0.19 24.00 7.96 0.05 0.10 2335 ·0.07 99.68 АУЕ 27.61 0.08 3.93 359 4.98 0.16 2853 4.19 0.05 0;10 26.36 0.06 3 41К 41.14 1.05 18.81 5.19 . 523 0.70 3.95 933 4.08 022 957 035 99.62 4 451 47.82 2.09 15.86 8.14 2.90 0.09 4.42 6.82 420 156 553 029 99.72 5 35А 43.80 0.47 1737 3.91 7.02 0.13 6.63 1050 1.72 2.46 ·6.19 0.10 10030 6 41L 42.00 056 1637 330 3.03 0.15 3.77 12.12 359 131 13.15 0.15 99.50 7 34А 4350 2.41 17.54 250 1131 0.15 7.54 4.97 333 028 5.87 031 99.71 8 32А 46.46 3.11 15.78 431 10.00 0.14 521 533 322 0.45 520 0.42 99.63 9 45Z 4727 1.98 15.09 1.66 958 0.09 8.40 5.70 3.16 053 5.85 031 99.62 ос> 10 45К 51.75 032 17.09 1.77 7.95 · 0.07 6.67 627 422 020 3.14 0.11 9956 '" 11 З6А 5350 232 15.85 2.96 7.47 0.11 4.69- 3.69 5.00 0.10 437 033 10039 12 F 45.70 1.58 16.75 12.70 1.87 0.13 339 6.96 2.78 138 3.01 0.00 9625 13 42D '48.48 1.00 21.55 7.03 550 0.08 5.70 1.70 4.00 1.9"2 2.36 022 9954 АУЕ 46.49 1.54 17.10 4.86 653 0.17 5.49 6.67 357 0.95 5.84 0.24 14 38А 71.10 130 16.53 1.12 4.54 0.08 0.81 1.13 0.90 1.46 0.64 0.15 99.76 15 . 35G 7130 030 15.00 1.49 0.78 0.01 0.81 0.85 3.90 4.40 0.95 0.01 99.80 16 . 35W 75.36 0.04 13.66 0.71 0.82 0.01 020 0.42 423 4�0 033 0.01 99.89 17 M16D 69.80 0.84 11.76 1.00 4.10 028 1.72 2.45 154 2.46 323 0.00 99.18 18 М1БG 71.68 052 1120 2.70 . 252 0.08 0.87 0.82 1.52 2.75 4.46 0.01 99.13 19 39Е 7227 227 15.70 1.83 1.41 0;04 030 035 0.16 0.75 4.15 0.03 9926 АУЕ 71.9"2 0.88 13.98 1.48 2.36 0.08 0.79 1.00 2.04 2.65 229 0.04

## 1, 2: ultrabasites, highly serpentinized. ##3-11: reenstone slates (spilites, diabases,. tuffs, etc). ## 12-13: greenstone slate diaplectites. ## 14-16: porphyroids; ## 17-19: роср� yroid diaplectites. ТаЫе 19 l.ЬашаnsЫпcrater target rocks : Silurian flinty slates (quartzites), veiJi guartz and carresponding diaplectites

N Sp.# Si02 Тi02 Аl2Оз F�Оз FeO МnО MgO Сао Na20 К2О Lj. P2051sum 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 '15 1 25А-88 . 73.95 0.60 11.76 - 4.02 0.13 1.49 0.18 2.10 2.58 2.92 .0.08 99.81 2 26-88 75.60 427 0.04 1.10 023 1.54 2.54 0.13 99.36 0.63 10.85 . 2.43 3 25В-88 7837 0.53 1038 2.70 0.08 1.09 '0.17 1.61 2.41 2.16 0.09 99.59 4 M-70N 78.56 0.50 11.50 2.11 0.05 0.60 023 0.42 229 3.40 oro 99.66 5 М"700 78.09 . 0.45 10.51 1.95 0.08 0.67 0.53 .0.59 2.01 326 0.15 9829 6 М-70Р 79.13 038 10.83 2.13 0.03 0.72 . 029 0.13 2.10 2.96 0.00 98.70 7 M-70R 79.43 032 9.86 335 0.00 0.74 0.36 0.14 2.47 2.54 0.01 9922 8 35В 79.70 030 8.77 3.06 1.81 0.04 1.02 0.42 3.44 0.80 0.67 0.08 100.11 9 43L-l . 80.50 024 835 031 2.19 0.04 1.45 0.57 022 0.12 6.00 0.09 100.08 10 43L-3 8230 0.44. 8.01 0.82 1.69 0.01 0.61 0.71 1.55 1.87 1.43 0.12 99.56 00 11 17-3 85.64 037 5.55 1.40 128 0.06 025 · 0.98 1.05 131 1.74 0.07 99.70 -...1 12 М12В 86.61 027 4.74 0.49 0.08 0.15 0.63 0.12 0.46 6.11 0.00 99.66 13 М70М 8738 023 5.75 228 0.05 0.48 . 027 0.09 1.14 1.78 0.01 99.46 14 М70G 87.70 0.10 3.48 3.88 0.16 0.48 025 0.07 0.70 1.76 0,00 98.58 15 М12А 88.36 о.з7 3.84 1.10 0.44 0.06 0.42 . 0.80 1.78 0.92 1.12 0.02 9923 16 43L-2 88.68 024 4.68 034 1.44 0.01 122 0.57 130 0.77 0.67 0.08 100.00 17 1-1 89.00 0.14 4.06 2.93 0.62 0.05 030 0.42 0.05 0.93 1.47 0.10 100.07 18 М70G 89.40 0.10 5.85 0.57 0.00 0.41 0.09 0.08 122 1.60 0.00 9932 19 М70Е 89.55 0.08 5.51 0.15 031 0.00 0.40 029 0.07 0.98 1.75 0.01 99.10 20 D5E 89.50 0.14 3.97 0.52 1.61 0.14 0.50 0.63 032 0.56 1.58 0.14 99.61 21 M70ZH 9033 020 5.03 134 0.00 0.43 0.16 0.06 1.01 124 0.00 99.80 22 M70L 91.48 0.07 5.17 026 0.00 0.42 027 0.12 0.97 1.18 0.01 99.95 2з 24-1 91.40 0.04 033 127 2.93 0.05 1.80 0.42 0.05 0.10 1.02 0.11 99.52 24 ' М70К 92.14 0.05 3.45 0.76 0.06 0.41 0.17 0.10 0.64 1.08 0.02 98.88 25 29В 91.58 0.16 4.05 0.03 124 0.01 020 0.71 0.18 0.94 0.46 0.06 99.62 26 M70Z 9229 ' 0.06 3.94 038 0.00 0.41 020 0.07 0.68 1.02 0.02 99.07 · 27 M70W 9333 0.05 339 0.55 0.00 024 020 0.10 039 1.10 . 0.01 99.36 28 15-1 93.83 0.09 1.01 1.73 0.01 035 0.55 . 0.05 025 1.69 0.07 99.63 · Table 19 (end)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

29 29А 94.52 0.07 1.52 0.18 1.78 0.02 020 0.57 0.07 031 030 0.13 99.67 зо M70I 9532 0.00 2.59 039 ОЛl 024 0.15 0.06 0.45 0.78 0.02 100Лl 31 М70А 95.61 0.00 2.07 031 0.00 028 0.09 0.05 0.36 0.53 0.01 9931 32 F 98.40 0.02 0.40 0.07 030 0.01 031 026 0.10 0.06 030 0.00 10023 33 383 7438 0.52 9.45 1.42 1.15 0.02 1.02 434 0.40 1.40 5.47 0.12 99.69 з4 32В 75.54 0.63 9.45 127 2.15 0.05 122 1.89 1зз 1.81 3.82 025 99.41 35 M15W 78.40 034 6.93 0.58 2.44 0.15 1.44 3.77 1.54 1.01 3.08 0.00 99.68 36 М32В 7923 0.42 734 2.51 1.80 0.09 0.75 1.49 1.70 1.48 2.70 0.01 99.52 37 М15О 79.68 0.53 8.64 2.15 123 0.10 1.08 029 1.06 1.93 2.48 0.02 99.19 з8 38G 80.50 0.18 5.40 1.18 223 0.08 122 3.69 035 0.87 4.06 0.16 99.92 00 39 38В 80.70 020 3.67 2Лl 1.65 0.03 1.12 426 030 0.43 5.18 0.16 99.71 00 40 М32О 82.18 024 828 0.48 1.54 0.06 033 1.00 2.57 0.54 2.42 0.00 99.64 41 M20W 83.60 029 6.54 030 1.89 0.07 0.87 120 131 0.78 3.56 0.01 100.42 42 М20О 83.87 026 434 1.45 037 0.11 0.72 324 132 0.68 4.09 0.00 100.45 43 32В 83.92 038 5.40 0.40 1.68 0.04 0.51 227 1.07 0.78 324 0.15 99.84 44 F 88.09 023 4.80 0.60 1.44 0.00 034 0.77 0.57 0.10 0.00 0.00 96.94 45 М20В 88.88 023 3.48 0.74 0.51 0.05 0.49 0.91 1.18 0.59 2.90 0.01 99.97 46 31Н 9038 020 2.36 031 223 0.05 0.36 0.85 0.18 025 2.78 0.11 100.06 47 · F 98.02 0.00 0.10 031 028 0.01 020 030 0.09 0.06 0.00 0.00 9937 АУЕ 85.85 025 5.69 1.02 1.70 0.05 0.66 0.91 0.69 1.00 221 0.06 УЛR 43.08 0.03 9.84 0.85 0.92 0.00 0.17 125 0.62 0.51 231 0.00 STD 6.56 0.18 3.14 0.92 0.96 0.04 0.41 1.12 0.79 0.72 1.52 0.06

## 1-31: unaltered sedimепtа target rocks; #32: vein artz; ## 33-47: diaplectites of the same rocks. # 47: vein guartz diaplectite named as "lechatellierite" ьу (й lorenskyand Dabizha 1 gg:80), with the relict coesite. Table 20 Paleogenic liandy clays and.sands from the Zhamanshin.impact crater and its viciriities.

N Sp.# Si02 Тi02 Аl2Оз F�Оз FeO MnO MgO СаО Na20 К2О L.i. Р205 Sum

1 2 3 4 5 6 7 8 9 1Q 11 12 13 14 15

1 7 52.67 037 16.15 4.70 0.54 1.65 529 038 1.17 ·1726 0.10 iOO28 2 67 57.45 0.73 · 12.94 5.18 0.02 1.92 6.63 0.83 2.36 11.61 0.12 99.79 3 66 5828 0.69 · 12.11 5.80 0.02 1.74 6.05 0.75 227 11.93 0.14 99.78 4 64 64.14 0.66 11.42 5.73 0.01 1.42 355 0.62 1.97 9.86 023 99.61 5 65 65.92 0.67 9.81 5.50 0.00 1.62 429 0.66 1.92 932 0.12 99.83 6 NW 5826 0.72 16.45 629 0.05 2.43 157 230 2.40 930 0.47 10024 7 W 59.82 0.96 16.74 8.00 · 0.10 2.19 126 1.68 2.50 732 0.15 100.72 8 NE 60.06 0.90 13.65 7.01 0.08 220 4.79 127 1.80 7.73 027 99.76 9 N 62.84 0.77 1733 5.06 0.03 1.59 1.47 155 2.63 5.40 0.17 98.84 00 10 Е 65.49 0.92 · 13.13 5.83 0.06 2.03 2.08 0.67 2.00 6.19 033 98.73 \о 11 SW 67.70 0.96 13.41 4.73 0.05 2.07 1.85 1.86 220 4.77 0.13 99.73 12 6-1 86.95 058 5.16 233 0.09 027 0.40 0.88 1.63 1.66 0.06 100.01 13 6-2 88.62 053 430 2.16 0.03 020 0.47 0.65 130 2.04 0.05. 10035 14 6-3 93.06 0.41 2.76 129 0.03 0.16 024 035 120 . 0.44 0.03 99.97 15 6-4 89.18 0.62 433 1.87 0.06 025 032 030 1.50 1.44 0.04 99.91 16 44 54.94 0.91 18.65 8.43 0.02 1.48 0.42 029 1.82 13.03 0.08 100.07 17 45 54.50 0.81 . 17.05 8.94 0.02 129 0.58 0.43 2.13 13.86 0.09 99:70 18 46 56.88 0.76 15.78 8.92 0.02 124 031 0.46 2.14 13.21 0.09 99.81 19 47 55.61 0.68 14.63 934 0.02 122 0.42 0.68 1.59 15.05 0.08 9932 20 56 6728 0.89 12.83 5.13 0.02 134 031 1�08 2.15 8.53 . 0.10 .99.66 21 74 68.06 0.72 6.98 424 0.02 • 1.04 1.62 223 1.94 10.04 0.10 96.99 22 8/2 80.01 0.60 8.68 234 0.03 0.73 0.53 0.82 235 3.58 0.03 99.70 23 10/10 7037 0.68 1038 5.08 0.06 1.85 0.72 1.51 .1.92 7.49 0.09 100.15 24 10/9 7230 0.64 9.78 4.52 0.05 1.75 0.65 1.43 1.81 6.94 0.09 100.96 25 10/8 74.13 0.62 8.43 4.18 0.06 1.91 1.14 137 1.73 6.62 0.10 10029 26 10/7 74.02 053 7.89 439 0.05 1.94 1.47 120 1.60 6.78 0.08 99.95 27 10/6 74.95 0.58 7.88 3.95 0.06 1.90 1.25 125 1.77 6.19 0.07 99.85 Table 20 (end)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

28 10/5 84.98 0.47 4.93 2.66 0.06 0.87 0.45 0.88 1.42 332 0.05 100.09 29 11/8 73.41 0.75 939 435 0.03 1.14 0.48 1.90 2.01 6.57 0.10 100.13 3D 11/7 74.82 0.69 8.06 3.98 0.03 0.97 0.84 2.07 231 627 021 10025 31 11/6 69.43 0.67 920 422 0.03 1.09 1.81 1.93 2.02 922 0.08 100.70 32 11/5 65.09 0.78 10.57 4.94 0.03 1.40 2.01 1.92 1.96 11.12 0.13 99.95 33 11/4 68.67 0.71 9.87 4.54 0.03 127 122 1.98 1.75 9.67 0.14 100.85 з4 12/5 8З.13 036 4.86 2.75 0.10 0.56 0.95 1.48 1.14 4.18 0.05 99.56 35 12/4 80.65 039 5.46 3.10 0.08 0.66 1.47 1.41 1.16 5.57 0.05 100.00 з6 12/3 73.69 0.50 7.44 3.48 029 0.73 233 133 138 832 0.07 99.56 \с) 37 12/2 7428 0.80 9.62 4.06 0.03 0.99 034 1.72 2.16 5.77 0.09 100.86 с 38 121/1 68.19 0.92 11.46 628 0.05 128 0.44 129 · 2.18 7.74 99.83 АУЕ 69.68 0.68 11.83 4.88 0.06 133 1.63 120 1.88 7.77 0.12 VAR 111.92 0.03 2620 3.89 0.01 035 2.74 034 0.15 14.50 0.01 STD 10.58 0.16 5.12 1.97 0.09 0.59 1.66 0.58 039 3.81 0.09

## 1-15: within the crater; Sp. ## 64-67: bore hole 101, 14 m below the surface; Sp.# 7: small pit near the spring, SW part of the crater; Sp. # NW, SW, etc: soft surface material from various parts of the crater rim (after Ja.Вoiko). Sp.# 6(1-4):soft surface material from . the SW Irghizite strewn Field. ## 16-38: vicinities of the Zhamanshin Crater. # 44-47: bore hole 4 km Е of the crater rim "gate", beneath the Holocene Co.ver of 7 m thick; Sp. #74: pit - 20 km ENE of the Crater; Sp.# 8/2: 3 km S of the crater rim, small satellite crater. Sp. ##10/5-10/10 and Sp. ## 11/4-11/8:road quarries, 11-12 km ENE of the crater rim; Sp. ## 12/1-5: road quarry - 14 km ENE of the crater rim. ТаЫе 21 Late Pleistocene river sands of the remote localities

N Sp.# Si02 . . Тi02 А12Оз FezОз FeO МnО ·MgO СаО Na20 К2О L.i. Р205 Sum

1 5 71.68 039 3.93 1.93 0.02 032 10.89 0.36 125 9.03 0.04 99.84 2 86 77.66 0.85 8.02 535 0.02 0.68 0.43 0.54 1.71 423 . 0.07 99.56

10 3 84 79.94 0.76 8.03 3.74 0.02 0.62 0.43 0.50 1.63 4.04 0.05 99.76 ..... 4 3 79.94 0.40 6.59 3.05 0.02 0.71 2.49 0.13 1.52 4.86 0.04 99.75 5 81 8023 0.76 7.73 3.59 0.02 0.58 0.45 0.56 1.67 420 ош 99.88

АУЕ 77.89 0.63 6.86 3.53 0.02 0.58 2.94 0.42 1.56 527 0.06

Definite Pleistocene sediments of 0.7-1 т.у. age Ьауе not Ьееn found in the Zhamanshin are� ..These analyses are аn example of а possible Pleistocenesedimentation in the Aral region. Sp.## 3,5: 5 m-high terrace of the Turgai river, 170 km NE of the Zhamanshin crater. Sp. ## 81, 84,86: ra vine near the Turgai village, 230 km NE of the crater. ТаЫе 22

Holocene loess-like sediments within (Ье Zbamanshin crater and lUacent area

N Sp.# Si02 Тi02 А12Оз FezОз FeO МпО MgO СаО Na20 К2О . Lj. Р205 Surn 1 2' 3 4 5 6 7 8 9 10 11 12 13 14 15 .. 1 59 66.81 0.77 12.52 5.01 0.00 1.34 1.97 0.84 . 231 8.03 0.13 99.73 2 58 67.62 0.74 11.73 4.77 0.01 130 1.84 1.05 2.18 8.43 0.12 99.79 3 24 68.00 0.74 11.71 4.82 0.02 139 229 0.69 2.13 7.95 0.10 99.91 4 60 69.90 0.70 11.17 4.78 0.01 121 131 0.83 2.12 7.42 0.11 99.63 5 20 70.60 0.60 929 4.89 0.00 132 2.08 1.14 1.69 8.08 0.13 99.87 6 44В 71.80 0.79 11.41 4.72 0.04 1.74 0.99 0.98 2.12 531 0.12 100.07 7 57 71.90 0.71 10.44 4.94 0.02 0.85 0.62 0.93 2.11 7.02 0.09 99.70 8 61 72.00 0.77 10.79 4.47 0.01 1.10 0.99 0.91 2.18 6.41 0.10 99.73 9 44А 72.80 0.75 1128 5.64 0.04 2.02 1.42 0.92 2.08 4.66 0.14 101.84 'D 10 28А 7336 0.78 9.96 222 0.02 0.51 2.56 1.50 2.54 6.75 0.10 10030 N 11 63 7337 0.76 9.97 438 0.01 1.02 1.01 0.75 1.93 639 0.11 99.70 12 23 7421 0.64 9.34 3.97 0.00 1.07 1.71 0.70 1.81 626 0.07 .99.78 13 26А 75.41 0.80 10.69 438 0.04 1.17 128 0.83 2.08 3.06 0.07 99.81 14 62 76.46 0.69 8.87 4.06 0.04 0.82 0.77 0.59 1.85 5.43 0.10 99.68 15 21 82.10 0.40 4.96 4.19 0.02 0.60 0.93 0.79 1.10 4.50 0.18 99.77 16 29 7128 0.79 10.85 4.66 0.02 1.00 0.95 0.91 2.19 7.10 0.10 99.85 17 30 73.70 0.55 8.80 4.78 0.02 1.15 1.75 0.68 1.55 6.67 0.09 99.74 18 31 7922 0.60 7.26 4.45 0.02 0.61 0.44 0.99 1.69 4.40 0.08 99.76 19 32 7835 0.59 6.95 3.95· 0.02 1.12 0,48 1.59 1.44 530 0.08 99.87 20 35 70.10 0.79 10.98 4.89 0.02 1.10 1.08 0.89 224 7.64 0.10 99.83 21 36 72.10 0.76 10.56 4.40 0.02 0.94 0.83 0.73 2.16 7.07 0.10 99.67 22 37 74.55 0.72 9.64 430 0.02 0.85 0.72 0.74 2.17 6.04 0.10 99.85 23 38 70.06 0.79 1124 4.92 0.02 1.07 0.83 0.73 2.17 7.78 0.11 99.72 24 39 62.98 0.78 13.40 6.11 0.02 1.41 136 0.48 2.16 10.65 0.12 99.47 25 40 67.18 0.75 11.40 535 0.02 132 2.87 0.81 2.10 7.99 0.10 99.89 26 41 75.60 0.63 8.76 4.61 0.02 1.03 1.57 0.52 1.60 536 0.09 99.79 27 42 75.94 0.50 8.66 430 0.02 0.89 1.68 0.57 1.89 523 0.08 99.76 28 43 75.96 0.40 5.82 6.96 0.02 0.97 2.80 0.64 0.95 4.82 035 99.69 29 54 69.67 0.63 10.04 527 0.02 1.63 1.60 0.86 1.77 8.11 0.11 99.71 зо 55 71.08 0.63 10.47 .5.08 0.02 137 , 0.99 0.81 1.79 7.18 0.08 99.50 31 68 74.82 0.66 8.42 4.13 0.02 1.00 1.96 0.84 1.97 5.79 0.08 99.69 32 69 81.57 0.54 630 426 0.02 0.72 1.13 0.50 137 3.10 0.09 99.60 33 70 74.42 0.74 8.81 4.11 0.02 1.05 225 0.84 1.83 5.48 0.09 99.64 34 71 78.40 0.77 7.62 3.66 0.02 0.71 1.78 0.78 1.86 4.02 0.08 99.70 35 72 78.42 1.75 726 3.91 0.02 0.73 1.65 0.65 1.72 3.40 0.09 99.60 36 75 89.50 0.18 3.10 2.80 0.02 029 0.44 .0.44 0.60 2.45 0.06 99.88 37 76 90.94 020 2.87 2.76 0.02 027 О34 0.49 0.62 126 0.08 99.85 38 77 83.63 029 4.36 2.46 0.02 0.50 121 1.02 0.85 527 0.05 99.66 39 78 9027 023 3.48 229 0.02 026 027 0.48 0.70 1.76 0.06 99.82 40 8/1 76.94 0.66 9.79 3.11 0.04 0.88 0.41 0.77 ' 234 4.80 0.05 99.79 41 8/3 86.06 0.68 6.08 2.02 0.04 038 035 0.69 224 1.54 0.05 100.13 42 10/4 ' 85.71 0.47 4.93 2.43 0.05 0.77 035 0.76 1.45 3.08 0.05 100.05 43 10/3 , 90.68 0.48 339 2.10 0.05 033 030 0.52 121 0.94 0.04 100.04 44 10/2 90.99 0.47 3.44 1.72 0.05 034 028 0.40 120 0.98 0.04 99.91 45 10/1 90.96 0.4 3.44 1.67 0.04 034 030 035 121 122 0.05 99.98 46 11/3 77.40 0.60 7.61 3.81 0.16 1.00 027 133 1.51 620 0.12 100Ш 'D 47 11/2 88.49 0.48 420 1.87 0.05 0.71 021 0.54 1.23 2.28 0.05 100.11 w 48 11/1 92.83 0.37 2.65 1.52 0.03 023 022 030 0.97 0.76 0.04 99.92 49 12/16 87.14 0.46 430 2.89 0.11 0.46 025 0.62 1.11 2.52 0.05 99.91 50 12/15 84.15 0.51 5.46 3.05 · 0.36 0.61 0.51 0.57 1.19 3.44 0.05 99.90 51 12/14 78.51 0.61 7.09 3.62 0.07 1.07 1.18 0.69 1.66 5.60 0.08 100.18 52 12/13 71.53 0.60 9.26 4.49 0.07 1.67 1.68 0.74 1.71 8.06 0.09 99.90 53 12/9 63.70 0.63 9.51 434 0.08 1.65 2.64 3.53 1.78 12.06 0.08 100.02 54 12/8 72.32 0.53 6.91 3.41 123 0.96 232 1.98 139 8.72 0.06 99.83 55 12/10 6820 0.52 634 2.93 0.06 1.13 6.19 0.56 133 8.77 0.06 96.09 56 12/11 4825 0.45 6.97 3.12 0.04 1.40 1230 0.64 126 16.01 0.06 90.50 57 12/12 49.98 0.48 7.25 3.41 0.05 1.48 11.91 0.47 131 ' 16.59 0.07 93.00 58 12/7 81.44 0.60 5.89 2.86 0.77 0.69 129 129 126 4.40 0.05 100.55 59 12/6 85.41 0.74 4.92 2.58 0.44 0.56 0.49 0.91 129 2.84 0.05 10023 60 83А 73.65 0.72 9.49 4.42 0.00 0.90 0.41 1.50 2.19 6.50 0.12 99.90 61 6 75.80 0.50 7.08 3.88 0.01 1.00 2.76 0.69 136 6.48 0.08 99.64 62 2 77.72 0.58 7.93 3.47 0.01 0.78 2.03 0.53 1.83 4.80 0.24 99.92 63 83 77.84 0.77 7.81 5.59 0.00 0.59 0.49 0.52 1.73 4.44 0.11 99.89 64 7 78.96 032 3.85 2.88 0.00 0.70 5.96 027 0.94 5.96 0.05 99.89 ТаЫе 22 (end)

1 2 3 4 5 6 7 8 9 10 n .12 ц. 14 15

65 82 80.57 0.75 8.13 3.15 0.01 059 0.47 0.63 1.85 358 0.07 99.80 66 1 80.96 056. 6.81 3.45 0.02 0.60 1.43 053 1.60 3.84 0.06 99.86 67 79 ' 81.61 0.80 6.74 4.14 0.00 0.50 0.41 0.42 151 356 0.09 99.78 68 14 82.73 0.49 637 353 0.01 0.62 0.58 0.61 151 326 0.06 99.77 69 13 82.93 0.46 5.40 3.78 0.01 0.62 1.40 0.47 1.18 3.60 0.06 99.91 70 80 83.43 0.69 6.46 2.72 - 0.02 036 0.40 0.49 1.64 3.51 0.07 99.79 71 9 8624 032 4.82 3.42 0.02 051 035 024 1.05 2.90 0.05 99.92 72 10 87.02 023 3.76 2.45 0.00 0.46 1.71 022 0.86 2.99 0.04 99.74 73 15 87.89 0.47 3.66 3.91 0.02 037 0.43 023 0.89 1.9S 0.06 99.91

\о АУЕ 77.05 0.61 · 7.66 3.83 0.06 0.89 158 0.77 1.62 5.45 0.09 � VAR 73.92 0.04 7.49 123 0.03 0.16 4.30 021 022 8:93 0.00 SТD. 8.60 021 2.74 1.11 0.17 0.40 2.07 0.45 0.47 2.99 0.05

1-15: FUling of the Zhaтanshin сгшег funnel. sp ##571i2: deep bore hole 103, 14 т thick homogeneous loess-like cover above the allogenic breccia. Sp.# 63:anom aly layer at the botlom of the same loess-like cover. ## 2O-24:wall of the dry small ravine, NE part of the crater Пт. Sp.## 44а,Ь,26а, 28а : surface sediments from various places of the round flat depression surrounded ьуthe сщtеr Пm. 16-59: Zhaтanshin смег vicinity: loess-like cover above the anomaly layer and Pale ene beds.Sp. #29-32: small road quarry - 9 km ENE of the crater Пm. 35-43 .: bore hole 4 km Е of the crater Пm.Sp.## 54- �: small road quarry - 12 km ЕNБ of the crater Пm. sp ##68-72. : boreSf'## ole 2 km Е of the riПl. Sp. 75-78:## lake shore wall, - 14 km ЕNБ of the crащ rim. Sp.##·8/1.3 .: small satelite crater, 3 km S of the Пm. Sp. ## 10/1-4. 11.small andSp.##1111-3: road quarry - 12 km of the crater Пт. Sp. ## 12/1-5: road quarry - 14 km ЕNБ of the crater Пm. .. 60-73:Reтote locaIUles. Sp.79-8За: ## ravine near the Turgai village, 230 km NE from the crater. Sp.##12: 5 т - high terrace of the Turgai river, 170 kmNE of the crater ..Sp.fi: ravine - 80km of the crater. SpJlJLl:3 т - high terrace of the Zhaman Telkara River, - 33 km NE of the crater. Sp. # 10:9. small qU8.rry near the road from Irghiz village to Chelkar city, - 17 km NNW of the crater.. Sp.##13-15: the same, - 38km NNW of the crater. CONTENTS .

Inroduction ...... 3

History of the Zhamanshin Crater Study ....'...... 3 Previous age determinations ...... ; ...... 5 Тhermal stability study of the Zhamanshin tektites and impactite glasses ...... : ...... 8

Eission track age ofbasic impactites from deep bore holes ...... 11 Fission track age of the tektite-zhamanshinite remelted during the impact event ...... •· ...... •...... 12 Thermoluminescence analyses of the Zhamanshin glasses ...... 13 Paleomagnetic dating ...... 14 Geological age of the Zhamanshin impact crater ...... 15 ' Morphological features ...... '...... 15 Geomorphological features ...... ; ...... 16 Palinological data ...... 16 . Stratigraphicaldata . ' .' ...... < • • • • • • • • • • • • • • • • • • • • • • •• 16

Anomaly layer ...... • , 17 Chemical composition of the Zhamanshin glasses and target rocks ...... •...... 19

Melted impactites ...... : ...... 19 Muong Nong-type tektites-zhamanshinites ..: ...... : ...20 Tektites-irghisites ...... 21 Microtektites ...... � ...... •...... 23 Comparison of the Zhamanshin and Australasian tektite chemistry ...... •...... 23 Comparison of radiogenic ages of the Zhamanshin and the Australasian tektites ...... 25

Тhe main results and discussion ...... 36 Age of the Zhamanshin impact event ...... 36 Лgе paradox ...... - . .. 36 Composition and source of the Zhamanshin glasses ...... 37 Origin ofthe Zhamanshin tektites ...... '. ' ...... 38 Comparison of the Zhamanshin and Australasian tektites ...... - .....39

Spatial distribution of tektites ..... : .., ...... 39 Relationship between tektites and microtektites ...... 40 Summary ·...... 41 Referene:es ...... •...... � ...... 46 Appendix (petrochemical data> ...... 55 Утверждено R печати Институтом геологии СО РАН

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