GRV 90027 is a Martian lherzolitic shergottites(L-S)containing poikilitic,non-poikilitic,and melted pocket components.GRV 99027 is mainly composed of olive(55 vol%)and pyroxene(37.5 vol%),with minor maskelynite(6 vol%)and chromite(1.5 vol%),and trace whitelockite and troilite,ect.In this paper,the mineralogy and petrology of GRV 99027 are reported;in addition,the geochemical characteristics of the REEs and H isotopes in the GRV 99027 are also further investigated.The ΣREE in GRV 99027 is relatively low;HREEs are enriched in olivine and pyroxene grains;LREEs are enriched in plagioclase with a high positive Eu anomaly.High ΣREE value is found in rare mineral whitlockite(less than 0.2 vol%),LREE≈HREE,and whitlockite has a negative Eu anomaly.The REE distribution patterns of the whole-rock of GRV 99027 is similar to but different from that of other L-S Martian meteorites,indicating that they came from different location of Mars.GRV 99027 has a high δD value.Different water-bearing minerals give different contribution for δD value.The δD of phosphates generally does not correlate with water content,and δD has a weak negative correlation with water content.GRV 99027 can be classified as an L-S Martian meteorite based on mineralogical assemblage patterns,REE distribution patterns,and hydrogen isotope.The isotope data of Sr,Nd,Pb,Os and REE from other L-S Martian meteorites were collected to discuss the formation history of the GRV 99027.Similar to other L-S Martian meteorites,GRV 99027 originated from part of Mar's mantle;during one strong impact event about 4M years ago,the meteorites were ejected from deep mantle into space,and traveled for a different duration in space(indicated by different cosmic exposure time),and captured by the Earth later in different time,ultimately falling on the Antarctica as L-S Martian meteorites.
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