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Most of the Batain coast area, previously unmapped or mapped as Hawasina, is shown to be underlain by melange. This consists of blocks, up to 10 km long, of a variety of rocks in a scanty, seldom exposed sheared shaly matrix. Clasts include Triassic and younger Hawasina-type red cherts and shales; Mesozoic calciturbidites; Permian limestones and megabreccias (associated with basalts); ammonitico rosso type blocks (Triassic?); a limestone and pillow lava assemblage, probably Jurassic; Cretaceous ophiolite; and Upper Cretaceous sandstones with basement-derived debris flows. Deformation becomes increasingly complex northwards. WNW-vergent thrusts and folds, dominant in the south, appear to have been continuous with the south-vergent structures in the Hawasina, west of the Jebel Ja’alan basement uplift. The melange is interpreted as primarily tectonic but probably composite in origin. It is correlated with the Hawasina (Oman) Melange which underlies the Semail Ophiolite, west of the Jebel Ja’alan Uplift. It is compared with other Tethyan melanges.

Samples of ablated materials are analyzed to determine properties expected to be characteristic of particulates generated by the ablation of primitive meteoric bodies. Analyses of carbonaceous chondrite fusion crusts and samples artificially ablated in the laboratory indicate that the majority of meteor ablation debris should consist of assemblages of silicate minerals, principally olivine, and micron‐sized magnetite grains. It is expected that ablation debris of >10 μm should have abundances of Fe, Mg, Si, Ca, and Ni similar to those found in chondritic meteorites. Volatile species such as S, H2O, and Cl are lost during ablation and normally should not be found in ablated material. The major findings of this study are supported by the analysis of spherules collected in the atmosphere which are thought, on separate grounds, to be genuine meteor ablation products. The majority of meteoric bodies probably have cometary origins, and it is hoped that the ability to collect and reliably identify meteor ablation debris from terrestrial contaminants will provide an opportunity to do laboratory analysis on cometary matter.

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