月球角砾岩Bechar 003、NWA 13788和NWA 11110中岩屑溯源研究

月球角砾岩是月球陨石的代表性样品,含有多来源的岩屑,是揭示月球内-外动力演化历史的重要窗口。本文对Bechar 003、NWA 13788和NWA 11110月球陨石中的岩屑开展了岩相学、矿物学及地球化学分析,通过岩相、矿物成分、全岩主微量元素等岩石地化综合分析,旨在厘清这3块样品中岩屑的类型、来源与成因机制。结果表明,3块陨石内部的斜长辉长质冲击熔融岩屑、微斑熔融角砾岩屑、以及辉长质斜长岩屑的初始物质由均是月海玄武岩与月球高地岩石的混合物,不同初始物质成分的岩屑表明月表经历了冲击事件,并且冲击事件发生在月表的不同位置,冲击事件造成月球高地岩石与月海玄武岩或非月海溅射物的混合。     

岫岩陨石坑撞击角砾岩的岩相学和冲击变质特征SCIEI北大核心CSCD

撞击角砾岩是陨石撞击过程形成的特有岩石种类,是研究撞击成坑过程、陨石坑定年、矿物岩石冲击变质的理想对象。岫岩陨石坑是一个直径1800m的简单陨石坑,坑内有大量松散堆积的撞击角砾岩。本研究通过光学显微镜、费氏台、电子探针、X射线荧光光谱仪、电感耦合等离子质谱仪等分析测试手段,主要研究了岫岩陨石坑撞击角砾岩的岩相学和冲击变质特征,并在此基础上讨论了撞击角砾岩的形成过程和陨石坑的形貌特征。岫岩陨石坑内产出有三种撞击角砾岩,分别是来自上部的玄武质角砾岩和复成分岩屑角砾岩,以及底部的含熔体角砾岩。组成玄武质角砾岩和复成分岩屑角砾岩的碎屑受到的冲击程度较低,仅有少量石英发育面状变形页理,指示不超过20GPa的冲击压力。而组成含熔体角砾岩的碎屑受到了很强的冲击,发育了熔融硅酸盐玻璃、石英面状变形页理、柯石英、二氧化硅玻璃、击变长石玻璃、莱氏石等冲击变质特征,指示的峰值压力超过50GPa。本研究证实了含熔体角砾岩通常产出在简单陨石坑底部,由瞬间坑的坑缘和坑壁垮塌的岩石碎屑与坑底的冲击熔体混合形成。岫岩坑的真实深度是495m,真实深度与直径的比值为0.275,符合简单陨石坑的尺寸特征。陨石坑内的撞击角砾岩中心厚度为188m,与直径之比为0.104,略低于其它简单坑,可能是受丘陵地貌影响导致改造阶段垮塌到坑内的岩石角砾偏少。     

南极月球陨石MIL05035矿物学、岩石学及演化历史

月球陨石MIL05035岩石类型上属于普通辉石低钛玄武岩,粗粒辉长结构,无角砾化。主要矿物为辉石(60.2%)、斜长石(27.3%)和橄榄石(6.05%),次要矿物为石英(4.36%)、钛铁矿(1.25%)和陨硫铁(0.84%),含极少量富Ti、Fe尖晶石和磷灰石,广泛发育由钙铁辉石+铁橄榄石+石英组成的后成合晶三相集合体。辉石颗粒具有明显的化学成分不均匀性和出溶片晶,核部相对贫铁钙富镁(Fs30.2-60.8Wo14.2-35.0),边部富铁钙贫镁(Fs47.5-64.9Wo22.8-44.3)。熔长石化斜长石具有微弱的成分环带,边部相对富碱金属元素(Ab9.3-12.3,Or0.31-1.03),核部则相反(Ab7.6-10.6,Or0.12-0.36),含有未熔长石化的残留斜长石。橄榄石具有粗晶橄榄石(Fa95.5-96.6)和后成合晶中细粒橄榄石(Fa88.9-93.5)两种产状。石英具有脉状、团块状和蠕虫状等产状:脉状石英大部分转变为二氧化硅玻璃,核部石英具有较宽的拉曼谱特征峰(448~502cm-1),证明其经历了冲击变质与退变质作用;团块状石英分布于粗粒橄榄石颗粒间或橄榄石与斜长石和辉石接触边界上,与斜长石构成充填结构;蠕虫状石英分布于细粒后成合晶中。粗粒辉石边部铁辉石和后成合晶中辉石成分的继承性、结构上的延续性、光学特征上的冲击暗化现象、与冲击熔脉结构上的相关性和后成合晶中发育与粗粒辉石方向几乎一致的解理等方面的证据,认为后成合晶可能由于铁辉石在冲击压力释放与温度降低后的退变质作用下分解形成。根据岩石矿物结构观察、成分分析和MELTS模拟表明该陨石母岩的岩浆演化过程可能为:母岩浆在温度降低后首先产生极少量钛铁尖晶石、其次是普通辉石和钙长石先后结晶;随着温度下降,贫钙铁普通辉石、铁钙铁辉石和铁普通辉石等在普通辉石边部大量结晶,钙长石边部分异结晶少量培长石或拉长石;随着温度继续下降,早期结晶的普通辉石析出易变辉石等出溶片晶,橄榄石在辉石和斜长石边部结晶;其后,钛铁矿和陨硫铁析出,石英沿橄榄石和钙长石等先结晶矿物裂隙充填。出露月表后强烈的冲击变质作用使斜长石几乎全部转变为熔长石、石英大部分转变为二氧化硅玻璃,并具有一系列面状变形,冲击熔脉发育,冲击变质程度至少为S5。本研究为月球的岩浆演化和冲击变质过程提供了重要证据。     

陨石矿物种类的研究进展和矿物表

早在约 2 0 0年前 ,科学家就在铁陨石中鉴定出了两种陨石矿物——陨硫铁和金属铁—镍。到了 1 9世纪 80年代 ,陨石矿物的数量增加到 1 6种。 2 0世纪 60年代以来 ,随着显微镜的广泛应用 ,以及许多新的测试技术如 X射线衍射、电子探针、扫描电镜和透射电镜的应用 ,使更多的陨石矿物能被发现。1 967年 ( Mason列出 60种陨石矿物 )至 1 987年( Yudin和 Kolomenskiy列出了 2 0 0种陨石矿物 )的2 0年间陨石矿物种数增加到原来的 3倍多。1 991年Ulyanov完成了陨石、星际尘粒和玻璃陨石共 350种矿物的列表。Rubin〔1〕在前人工作的基础上 ,去掉…     

月球物质的Re-Os同位素组成研究：对月球后期增生历史的指示

Re-Os同位素体系是理解月球强亲铁元素的分布规律和示踪月球的后期增生历史的重要手段。目前人们对月球物质Re-Os同位素成分的了解还是十分有限的,已有的Re-Os同位素数据显示一些能代表月幔成分特征的月海玄武岩具有很低的Re和Os的浓度,以及类似于球粒陨石的187Os／188Os成分特征,而月球火山玻璃和月壤等表现出相对高的Re-Os丰度和相对富放射成因Re-Os同位素成分。一般认为月球月幔的Re、0s和其他强亲铁元素相对球粒陨石是非常亏损的,而地球地幔则具有相对较高的强亲铁元素丰度（0．008倍CI球粒陨石的丰度）。新的Re-Os同位素结果证明月幔确实是亏损的,但是月球和地球在太阳系演化的较晚时期都有外来的球粒陨石物质的大量加入,即后期增生（late accretion）过程,导致了月球和地球上部物质（如月球火山玻璃、月壤等）相对地富集Os同位素和强亲铁元素,这些外来物质的后期增生可能是长期和持续的,增生过程主要发生在3．9～4．4Ga。但目前仍不清楚后期增生的陨石物质是被逐渐加入的,还是在一个相对较短的时期大量加入的,因此尚需对更多的月球物质做进一步的Re-Os同位素和强亲铁元素成分的研究。     

一块新发现的月球陨石NWA 12279的岩石矿物学、源区和冲击变质作用

NWA 12279为2016年发现的一块斜长岩质月球陨石,由86%的斜长岩和14%的冲击熔融角砾岩组成。斜长岩具嵌晶结构,矿物组成主要为斜长石(70. 6%)、橄榄石(11. 3%)、辉石(10. 0%)、镁铝尖晶石(7. 0%),含少量石英、铬铁矿和钛铁矿;冲击熔融角砾岩具角砾状结构,主要由岩屑(斜长岩、辉长-橄长-斜长岩、微斑熔融角砾岩、辉长岩)、晶屑(橄榄石、辉石、斜长石、尖晶石)、玻屑和基质组成。斜长岩和角砾岩的矿物组成基本一致,主要为斜长石(An_(92. 9～98. 4))、紫苏辉石(Fs_(15. 5～32. 2)Wo_(2. 98～4. 22))、易变辉石(Fs_(27. 9～53. 1)Wo_(7. 19～14. 7))、普通辉石(Fs_(8. 42～38. 9)Wo_(17. 0～44. 1))、橄榄石(Fo_(53. 7～89. 4))、尖晶石[(Mg_(4. 97)Fe_(0. 86))_(5. 83)(Al_(11. 4)Cr_(0. 61))_(12. 0)O_(24)]。通过对陨石的矿物组成、碎屑组成、矿物成分、全岩成分和冲击变质特征进行研究,并和已发现的月球斜长岩进行了对比,认为该陨石可能起源于一个新的富含尖晶石的辉长橄长斜长岩高地。该陨石的斜长岩和角砾岩具有不同的冲击特征,斜长岩区域发育橄榄石面状破裂、斜长石熔长石化及含未熔融的辉石和橄榄石晶屑的冲击熔脉;角砾岩区域发育玻璃质熔脉、冲击熔体及岩石角砾化,这些特征限制了斜长岩区和角砾岩区经历的冲击压力峰值分别约为45 GPa和78 GPa,温度峰值分别约为1 100℃和1890℃,冲击变质阶段为S_5～S_6。     

亳县陨石矿物中包裹体的研究

通过对安徽亳县陨石矿物中包裹体的相态、成分和结构构造等研究可大致把它们分为晶质包裹体、熔融包裹体和气相包裹体三类。陨石的形成至少经历了星云凝聚—熔融—固态三个阶段。熔融阶段是陨石形成的一个重要阶段,其最低温度为1050℃～1200℃。各种类型包裹体成分的差异和分布不均匀性反映了原始熔浆成分的不均一性,也就是说“熔滴”在凝聚时化学成分和物理化学条件上的差异而导致陨石矿物中包裹体成分的差异,同时也反映了陨石矿物中包裹体在形成、演化过程中经历了多个阶段的特点。     

DaG476火星陨石的岩相学和矿物学研究

Dar al Gani 476(简称DaG 476)是1998年在利比亚撒哈拉沙漠中发现的第13块火星陨石.它属于含橄榄石斑晶的橄玻无球粒陨石[1,2],具典型火成分异结构,辉石和长石具典型的玄武结构,橄榄石以斑晶形式镶嵌于玄武岩中,副矿物主要有氧化物、硫化物和磷酸盐等.根据背散射电子像获得的矿物模式丰度(%,vol)为:辉石61,橄榄石22,熔长石12,冲击熔融包2,铬铁矿和钛铁矿等氧化物2,陨硫铁1,磷酸盐1,以及沙漠风化作用产生的碳酸盐1.     

天然和实验冲击球粒陨石矿物的变形变质比较研究

天然和实验冲击球粒陨石矿物的变形变质比较研究谢先德陈鸣戴诚达（中国科学院广州地球化学研究所，广州５１０６４０）Ａ．Ｅｌ．Ｇｏｒｅｓｙ（Ｍａｘ－ＰｌａｎｃｋＩｎｓｔｉｔｕｔｆｕｒＫｅｒｎｐｈｙｓｉｋ，６９０２９Ｈｅｉｄｅｌｂｅｒｇ，Ｇｅｒｍａｎｙ）关键...     

U-Pb zircon dating of the lunar meteorite Dhofar 1442

Dhofar 1442 is one of the few lunar KREEP-rich meteorites, which contains KREEP norites and KREEP gabbronorite as well as low-Ti basalts and highly evolved granophyres. Zircon is a typical accessory mineral of KREEP rocks. U-Th-Pb dates of 12 zircon grains (four of them were in two lithic clasts, and the others were fragments in the meteorite matrix) indicate that the zircons belong to at least two groups of different age: “ancient” (～4.31 Ga) and “young” (～3.95 Ga), which correspond to two major pulses of KREEP magmatism in the source region of the Dhofar 1442 meteorite. The zircon of the “young” group was most probably related to the crater ejecta of the Mare Imbrium Basin. The rock fragments dated at approximately 3.95 Ga have the composition of KREEP gabbronorite. The parental rocks of the zircon of the “ancient” group in the Dhofar 1442 meteorite are uncertain and could be highly evolved granophyres. This hypothesis is supported by the high Th (100–300 ppm) and U (150–400 ppm) contents. These zircon fragments of the “ancient” group, higher than in the “young” group (<50 ppm Th and <70 ppm U) and are typical of zircon from lunar granitic rocks. The composition of the products of KREEP magmatism in the source region of the Dhofar 1442 meteorite could vary from predominantly granitic to KREEP gabbronoritic at 4.3–3.9 Ga.     

Native silicon and iron silicides in the Dhofar 280 lunar meteorite

The Dhofar 280 lunar highland meteorite is the first one in which native silicon was identified in association with iron silicides. This association is surrounded by silicate material enriched in Si, Na, K, and S and occurs within an impact-melt matrix. Compared to the meteorite matrix, the objects with native Si and the silicate material around them show high Al-normalized concentrations of volatile elements and/or elements with low sensitivity to oxygen but are not any significantly enriched in refractory lithophile elements. Some lithophile elements (V, U, Sm, Eu, and Yb) seem to be contained in reduced forms, and this predetermines REE proportions atypical of lunar rocks and a very low Th/U ratio. The admixture of siderophile elements (Ni, Co, Ge, and Sb) suggests that the Si-bearing objects were contaminated with meteorite material and were produced by the impact reworking of lunar rocks. The high concentrations of volatile elements suggest that the genesis of these objects could be related to the condensation of silicate vapor generated during meteorite impacts. The reduction of silicon and other elements could take place in an impact vapor cloud, with the subsequent condensation of these elements together with volatile components. On the other hand, condensates of silicate vapor could be reduced by impact reworking of impact breccias. Impact-induced vaporization and condensation seem not to play any significant role in forming the composition of the lunar crust, but the contents of the products of such processes can be locally relatively high. The greatest amounts of silicate vapor were generated during significant impact events. For example, more than 70% of the total mass of lunar material evaporated in the course of impact events should have resulted from the collision of the Moon with a cosmic body that produced the Moon??s largest South Pole-Aitken basin.     

Enigmatic cathodoluminescent objects in the Dhofar 025 lunar meteorite: Origin and sources

Dhofar 025 is a lunar highland breccia consisting mainly of anorthositic, with less common noritic, gabbronoritic, and troctolitic material. Rare fragments of low-Ti basalts are present as well, but no KREEP (component enriched in incompatible elements) was found in the meteorite. The cathodoluminescence study of this meteorite showed that its impact–melt matrix contains unusual cathodoluminescent (CL) objects of feldspathic composition, which frequently contain microlites of Fe-Mg spinel (pleonaste). They were presumably formed by impact mixing and melting of olivine and plagioclase with subsequent rapid quenching of the impact melts. Such mixing could happen either during assimilation of anorthosites by picritic/troctolitic magmas or during impact melting of troctolites. The enrichment of CL objects of Dhofar 025 in incompatible trace elements suggests that the mafic component of the impact mixture may be related to the high-magnesium suite rocks, which are frequently enriched in KREEP component. The depletion of CL objects in alkalis indicates their possible relation with residual glasses formed by evaporation. However, the presence of FeO in most objects points to the insignificant extent of evaporation. Thus, evaporation cannot explain the enrichment of the CL objects in Al₂O₃ and other refractory components, although this process definitely took place in their formation. Their similarity to the lunar pink spinel anorthosites, whose existence was predicted from orbital data, serves as an argument in support of the possible formation of the latters by impact mixing.     

Aspects of U-Th fractionation in Tertiary limestones and calcretes of Dhofar,southern Oman

This paper presents findings from a comprehensive geochemical and geophysical re-examination of known radiogenic anomalies in Tertiary limestones and (sub-)recent calcretes of southwestern Dhofar in the Sultanate of Oman. U-Th-enrichments seem to be associated with deep-rooted fault systems that cross-cut C_org-rich shales at depths of some 800–1000?m, which generally show elevated gamma-ray levels in southern Oman and act as the initial geochemical trap. Metals and radiogenic elements, such as K (max?1945?ppm), U (max?44?ppm), and Th (max?26?ppm) mobilised from these rocks and emplaced higher up in the faults must have constituted radiogenic lineaments at and near the surface (observed in a different but difficult to access location). However, successive weathering partially obscured such anomalies through further re-mobilisation/-mineralisation processes within the calcretes that also enriched Sr and V. In these carbonates, uranium correlates positively with Sr but not very well with V, while thorium shows moderate positive correlations with Sr and V. Both U and Th are also not present (i.e., below the detection limits of a few ppm) in a second sample group that represents background conditions. Being much more immobile than U, Th remained closer to the original western fault positions of the examined site (outlined by magnetics and VLF-EM during the surveys), while uranium moved down-dip over the plateau and through underlying sub-horizontal strata towards the eastern fault system. Here, supergene Sr-enriched calcite preferentially incorporated U, thus reflecting the observed U-Th fractionation.     

Petrographic and mineralogical features of amblygonite- and spodumene-carrying granites

Granites carrying amblygonite and spodumene are characterized by 1) little if any, biotite; 2) strong alteration of rock-forming minerals; 3) development of potash feldspar over plagioclase in amblygonite granites; 4) development of plagioclase over potash feldspar + an epidote-garnet accessory mineral association in spodumene granite; 5) concentration of rubidium in amblygonite granites rich in potash feldspar. Amplygonite granite is most typical of greisenized granites and spodumene, of albitized granites. Chemically spodumene granites are of sodium type (Na/K>1), the amblygonite varieties are of potassium type (Na/K<1), and accessory epidote and tourmaline of spodumene and amblygonite granites are richer in lithium than those in common granites. Fluorine in the greisenizing solutions promoted transfer and deposition of lithium as amblygonite. Altered leucocratic granites are most likely to contain lithium minerals. The criterion for lithium presence is its higher content in pneumatolytic and hydrothermal minerals, tourmaline and epidote. — R.M. Hutchinson     

Petrogenesis of lunar meteorite EET 96008

Lunar meteorite EET 96008 is a fragmental breccia that predominantly consists of basaltic mineral clasts (0.5-2 mm), along with minor lithic fragments and breccia clasts. The matrix consists mainly of smaller mineral fragments (<0.5 mm), bound by glassy cement, the majority of which are pyroxene and plagioclase. The pyroxene possesses extensive exsolution lamellae. These lamellae, up to 1 μm in width, are atypical for mare-basalts. One of the distinguishing textures of EET 96008 is the presence of small pockets (∼400 × 500 μm) of mesostasis areas consisting of coarse (∼20 μm) intergrowths of ferroaugite, fayalite and Si-rich glass. Laths of ilmenite, armalcolite, apatite and whitlockite are also distributed in these areas. Ilmenite grains are abundant and dispersed throughout the thin sections. Chromite and ulvöspinel are present but in minor abundance. Troilite, generally rare in this rock, occurs as several grains in one pyroxene crystal. FeNi metal is conspicuously absent from this meteorite.The molar Fe/Mn ratio in olivines and pyroxenes and the age of the meteorite are evidence for a lunar origin. The mineralogy of EET 96008 shows close affinity to a mare-basalt source, albeit with possible minor highland/non-mare components. The bulk-rock, major-, trace- and rare-earth-element (REE) contents are similar to that of very low-titanium (VLT) basalts, which have experienced extreme fractional crystallization to the point of silicate liquid immiscibility. Mineralogical and textural features of this sample suggest that at least some of the breccia components were derived from a slow-cooled magma. The mineralogy and petrology of EET 96008 is strikingly similar to the lunar meteorite EET 87521, and we support the conclusion that EET 96008 and EET 87521 should be paired.Isochron ages of 3530 ± 270 Ma for apatite and 3519 ± 100 Ma for whitlockite of this rock are consistent with derivation from a mare-basalt precursor. These ages are within error of the low-Ti basalts, dated from the Apollo 12 and 15 sites. The whole-rock, platinum-group-element (PGE) contents of EET 96008 overlap with pristine low-Ti mare basalts, suggesting the presence of only a minimal extraterrestrial component.     

Compositions and possible sources of lunar meteorite NWA 4884

<正>1 Introduction Lunar mare basalts represent the products of partial remelting of deep mantle sources and provide windows into the compositions of lunar interior.Nine Apollo andLuna missions returned large amounts of mare basaltic samples,while remote sensing suggests that sampled basalts may cover only a small number of the lunar basalt     

Feldspathic lunar meteorites Pecora Escarpment 02007 and Dhofar 489: Contamination of the surface of the lunar highlands by post-basin impacts

PCA (Pecora Escarpment) 02007 and Dhofar 489 are both meteorites from the feldspathic highlands of the Moon. PCA 02007 is a feldspathic breccia consisting of lithified regolith from the lunar surface. It has concentrations of both incompatible and siderophile elements that are at the high end of the ranges for feldspathic lunar meteorites. Dhofar 489 is a feldspathic breccia composed mainly of impact-melted material from an unknown depth beneath the regolith. Concentrations of incompatible and siderophile elements are the lowest among brecciated lunar meteorites. Among 19 known feldspathic lunar meteorites, all of which presumably originate from random locations in the highlands, concentrations of incompatible elements like Sm and Th tend to increase with those of siderophile elements like Ir. Feldspathic meteorites with high concentrations of both suites of elements are usually regolith breccias. Iridium derives mainly from micrometeorites that accumulate in the regolith with duration of surface exposure. Micrometeorites have low concentrations of incompatible elements, however, so the correlation must reflect a three-component system. We postulate that the correlation between Sm and Ir occurs because the surface of the Feldspathic Highlands Terrane has become increasingly contaminated with time in Sm-rich material from the Procellarum KREEP Terrane that has been redistributed across the lunar surface by impacts of moderate-sized, post-basin impacts. The most Sm-rich regolith breccias among feldspathic lunar meteorites are about 3× enriched compared to the most Sm-poor breccias, but this level of enrichment requires only a few percent Sm-rich material typical of the Procellarum KREEP Terrane. The meteorite data suggest that nowhere in the feldspathic highlands are the concentrations of K, rare earths, and Th measured by the Lunar Prospector mission at the surface representative of the underlying “bedrock;” all surfaces covered by old regolith (as opposed to fresh ejecta) are at least slightly contaminated. Dhofar 489 is one of 15 paired lunar-meteorite stones from Oman (total mass of meteorite: 1037 g). On the basis of its unusually high Mg/Fe ratio, the meteorite is likely to have originated from northern feldspathic highlands.     

伊吾Eucrite陨石的岩石学、矿物学特征及其成因

Howardite-Eucrite-Diogenite(HED)族陨石是地球上目前发现数量最多的无球粒陨石类型,已发现的 HED族陨石主要来自于南极和非洲西北部的沙漠,本研究的 HED族陨石国际命名为Yiwu 001 ,发现于中国新疆维吾尔自治区伊吾县境内.系统的矿物学和岩石学研究显示,该陨石属于单矿物碎屑角砾岩 Eu...     

The variety of lithologies in the Yamato-86032 lunar meteorite: Implications for formation processes of the lunar crust

We performed a petrologic, mineralogical, geochemical, and isotopic study of several lithologies in the Y-86032 feldspathic breccia. This study leads us to conclude that Y-86032 likely originated on the lunar farside. Y-86032 is composed of several types of feldspathic clasts, granulitic breccias, and minor basaltic clasts set in a clastic matrix. We identify an “An97 anorthosite” that has An contents similar to those of nearside FANs. Mg′ (= molar Mg/(Mg + Fe) × 100) values vary significantly from ∼45 to ∼80 covering the ranges of both nearside FANs and the Mg′ gap between FANs and the Mg-suite. A light-gray feldspathic (LG) breccia making up ∼20% of the investigated slab (5.2 × 3.6 cm²) mainly consists of fragments of anorthosites (“An93 anorthosite”) more sodic than nearside FANs. LG also contains an augite-plagioclase clast which either could be genetically related to the An93 anorthosite or to slowly-cooled basaltic magma intruded into the precursor rock. The Na-rich nature of both An93 anorthosite and this clast indicates that the LG breccia was derived from a relatively Na-rich but incompatible-element-poor source. The Mg′ variation indicates that the “An97 anorthosite” is a genomict breccia of several types of primary anorthosites. Granulitic breccias in Y-86032 have relatively high Mg′ in mafic minerals. The highest Mg′ values in mafic minerals for the “An97 anorthosite” and granulitic breccias are similar to those of Mg-rich lithologies recently described in Dhofar 489. Basaltic clasts in the dark-gray matrix are aluminous, and the zoning trends of pyroxene are similar to those of VLT or LT basalts. The crystallization of these basaltic clasts pre-date the lithification age of the clastic matrix at ∼3.8 Ga. The low K contents of plagioclase in both the anorthositic and basaltic clasts and generally low incompatible element abundances in all the lithologies in Y-86032 indicate that KREEP was not involved during the formation of the precursor lithologies. This observation further suggests that urKREEP did not exist in the source regions of these igneous lithologies. All these facts support the idea that Y-86032 was derived from a region far distant from the PKT and that the lithic clasts and fragments are indigenous to that region. An An97 anorthositic clast studied here has distinct Sm-Nd isotopic systematics from those previously found for another An97 anorthositic clast and “An93 anorthosite”, and suggests either that An97 anorthosites come from isotopically diverse sources, or that the Sm-Nd isotopic systematics of this clast were reset ∼4.3 Ga ago. These lines of geochemical, isotopic, and petrologic evidence suggest that the lunar crust is geochemically more heterogeneous than previously thought.