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SummaryThe Dhajala meteorite shower, the latest recorded fall in India, comprises pieces fragmented near the lower limit of the break-up zone. The meteorite is a chondrite consisting of silica-rich chondrules making up to 34 vol.%, and fine-grained, Fe-Ni metal-rich groundmass admixed with a few irregular lithic fragments. Dhajala contains olivine of variable compositions, ortho- and clinopyroxenes, troilite, kamacite, taenite, chromite, and clear to opaque glass; magnetite occurs only in the fusion crust. The chondrules, which are of variable shape, mineral composition, and texture, represent different stages of quenching, leading to incomplete crystallization of minerals and some degree of disparity between norm and mode. Lithophile elements are less in Dhajala than in average chondrites. Two chemical analyses of Dhajala are presented and it has 27·10% total iron and 2·38 % sulphur (maximum). Chemical and petrological data indicate that it is an H3 olivine-bronzite chondrite. Evidence for the crystallization of chondrules from melt is overwhelming. Some chondrules have been permeated by later troilite and NiFe from the groundmass, which might have crystallized directly from a gaseous environment.

SUMMARY. The meteorite was an oriented polyhedron, which broke up into at least two parts after entry into the Earth's atmosphere. It has undergone some degree of terrestrial weathering. A cut surface of the meteorite shows light-grey interior with sporadic rusty-brown patches and a distinct brown alteration zone close to the fusion crust. Weathering has resulted in preferential replacement of NiFe by limonite, and veining of minerals by goethite.Rewari is an equilibrated chondrite with rare ghosts of chondrules and at least one lithic fragment. Composition of olivine, as indicated by microprobe analysis is Fa23, which agrees well with bulk wet chemical analysis; that indicated by da30 is Fa18_20. From the outer surface inwards, four petrographic zones can be distinguished in the meteorite: a skin, about O.Ol mm thick, a troilite-poor zone slightly thicker than the skin, a troilite-rich 'soaking zone', about o.5-o.6 mm thick, and a relatively coarsegrained interior. These are described in detail.The interior of the meteorite is composed of relatively coarse-grained crystalline silicates with disseminated metallic minerals including plessitic and zoned intergrowths ofkamacite and taenite. The matrix shows a high degree of integration with the chondrules. The coarse texture and zonation of taenite may be the result of protracted heat treatment responsible for recrystallization. The constituent grains show considerable shock effects such as fracturing, comminution, veins of shockmelted pseudotachylite, pressure twinning, and undulose Compared to average L-group chondrite it has a higher content of MgO and lower of SiO2, a little lower oxidation state, and tends to be enriched in siderophilic elements.THE Rewari meteorite was found by Edward A. Hopkins while he was in charge of the Indian Police of G u r g a o n district, H a r y a n a (then Punjab), India. To his recollection, the fall was in about July I929, 1 Publication authorized by the Director General, Geological Survey of India. (~ Copyright the Mineralogical Societyin a village about 96 km south of Delhi, near Rewari (28 ~ I2' N., 76~ 40' E.). The time gap between the dates of fall and collection is unknown.Out of the complete meteorite weighing 3.332 kg, L658 kg and 1.277 kg were obtained by the University Museum, Oxford, and the British Museum (Natural History), respectively. In 1976, by courtesy of M r Hopkins, the Geological Survey of India received 397 g of the meteorite and a fibre-glass replica of the stone before it was broken. It has been registered under n u m b e r 4IO of GSI. Morphology. S. P. DAS GUPTA E T AL.shows flowage of fusion crust towards it indicating that it was the rear during the last stage of the flight of the meteorite; the smooth top of the meteorite was apparently the front. The morphological features suggest that the meteorite broke into at least two parts along what is now the basal face after its entry into the atmosphere of the Earth. Mineral assemblage and texture. A cut surface of the meteorite shows light-grey interior ...

Petrified dicotyledonous woods are reported for the first time from the Middle Siwalik sediments of Jammu region (Jammu & Kashmir) in the northwestern part of India. The fossil woods resembling modem woods of Dipterocarpus Gaertn.f. (Dipterocarpaceae), Bischofia Blume (Euphorbiaceae), Cassia Linn. and Kingiodendron (Roxb.) Harms (Leguminosae) have been described in detail. Based on the distribution of comparable extant genera and species, prevalence of humid climate and existence of a mixed lowland tropical forest, comprising moist deciduous to evergreen elements, in the area have been deduced. Evidently Bischofia, Dipterocarpus and Kingiodendron existed in the Jammu region during the Late Tertiary time and subsequently shrunk in their distribution due to climatic change. They no longer grow in the area as they require more humid conditions. The occurrence of Dipterocarpus is particularly noteworthy as it extends the limit of Dipterocarpaceae in the geological past as far west as Jammu region in the north-west India. The arboreal C3 forms show that the landscape was well forested.