Northwest Africa (NWA) 4898 is the only low-Ti, high-Al basaltic lunar meteorite yet recognized. It predominantly consists of pyroxene (53.8 vol%) and plagioclase (38.6 vol %). Pyroxene has a wide range of compositions (En12–62Fs25–62Wo11–36), which display a continuous trend from Mg-rich cores toward Ca-rich mantles and then to Fe-rich rims. Plagioclase has relatively restricted compositions (...

Introduction: Shock modification of feldspar has been documented and experimentally reproduced in many studies since the recognition of maskelynite in Shergotty (1). Experimentally shocked feldspar samples have been well studied using chemical and crystallographic techniques (2-4). The crystallographic, site-specific characterization of major and minor elements is less well documented. We prese...

We report on the physical, chemical and mineral properties of a series of stone fragments recovered from the North Central Province of Sri Lanka following a witnessed fireball event on 29 December 2012. The stones exhibit highly porous poikilitic textures comprising of isotropic silica-rich/plagioclase-like hosts. Inclusions range in size and shape from mm-sized to smaller subangular grains fre...

Introduction: Shock metamorphism is one of the most fundamental processes in the history of Martian meteorites. Especially, shergottites experienced strong shock effects (>30 GPa) most likely when they were ejected from Mars [e.g., 1]. " Maskelynitization " of plagioclase and formation of shock melts are major effects due to this severe shock. QUE94201 (QUE) and Dhofar 378 (DHO) are basaltic sh...

Introduction: Previous research on noble gases within Martian meteorites has identified numerous distinct trapped Xe components that have characteristic isotopic signatures. Three distinct reservoirs are needed to explain these components. One reservoir is the Martian atmosphere, containing an elevated 129 Xe/ 132 Xe of 2.4 [1], which has clearly contributed to the Xe budget in the Martian mete...

Uranium-lead, Rb-Sr, and Sm-Nd isotopic analyses have been performed on the same whole-rock, mineral, and leachate fractions of the basaltic martian meteorite Zagami to better constrain the U-Pb isotopic systematics of martian materials. Although the Rb-Sr and Sm-Nd systems define concordant crystallization ages of 166 6 Ma and 166 12 Ma, respectively, the U-Pb isotopic system is disturbed. Nev...

Introduction: We have developed a model to calculate the cooling rate (or burial depth) by using the Fe-Mg chemical zoning profile of olivine, considering diffusional modification of zoning profiles as crystals grow by fractional crystallization from a melt [e.g., 1]. We applied the model to calculating cooling rates of olivines in the Semarkona (LL3.00) chondrite [2]. In this abstract, we appl...

Introduction: Phase transformations occurring during severe meteoritic impacts on planetary bodies are crucial indicators for estimating maximum shock pressures and temperatures. Their identification is not only essential for a detailed understanding of the shock history and origin of these meteorites, but also for deciphering their pre-shock petrology and magmatic evolution. Most shock-induced...

Introduction: We present the first mineralogical and oxygen isotope data for the new eucrite Northwest Africa (NWA) 5073 that has some unique features. This meteorite is a desert find with a total mass of 185 g and represents a non-brecciated unequili-brated eucrite with the coarsest texture ever found among samples of the HED suite. Results: NWA 5073 has a basaltic texture, mainly composed of ...

Introduction: The martian basaltic meteorites display enormous variation in their trace element and isotopic compositions. A subset of the shergottites including NWA1195, SaU005/008, DaG476, Y980459, Dhofar 019, and QUE94201 have many similar geochemical features, in addition to being the oldest shergottites. Strongly light-rare-earth element (LREE)-depleted REE patterns, low initial Sr and hig...