The Permian metavolcano–sedimentary sequence of the Jianglang and Taka domes in the southern Songpan–Ganzi Orogen is composed of bedded marble and sandwiched metabasalt. This study presents geochemistry, C–O–Nd isotope systematics and zircon U–Pb geochronology data to explore the formation mechanism and tectonic setting of its protolith. The marble samples have high δ 13C V-PDB (4.0 ‰ to −0.1 ‰) and δ 18O V-SMOW (16.3 ‰ to 13.6 ‰) values, with similar εNd( t) values (−5.3 to −7.2) to Late Permian conodonts. They display seawater-like features, e.g. superchondritic Y/Ho ratios, negative Ce and positive La, Gd and Y anomalies, indicating a marine carbonate protolith in oxygen-rich palaeoseawater. ![]() Their pronounced positive Eu anomalies suggest a contribution (5 % to 1 %) of submarine high- T hydrothermal fluids. The metabasalt samples show low SiO 2, high Fe 2O 3 T and MgO contents. They have low La/Sm, (Th/Ta) PM and (La/Nb) PM ratios, without correlations between MgO and other major/trace elements. These signatures could be attributed to insignificant fractional crystallization and crustal contamination. Their rare earth elements (REE) patterns, trace element profiles and trace element ratios are comparable to those of mid-ocean ridge basalt (MORB), suggesting a depleted MORB-type mantle reservoir. Melt modelling illustrates low degrees (<10 %) of partial melting in the spinel stability field at a depth of 30–60 km. Combined with previous studies, we advocate that the investigated metavolcano–sedimentary suquence was most likely formed during the Late Permian in a mature back-arc basin of the Palaeo-Tethys ocean.Bluebonnet house near Marble Falls in the Texas Hill Country Best Things to do in Marble Falls, Texas Moreover, the metabasalt contains 2453.7–258.9 Ma detrital zircons significantly related to the Palaeoproterozoic crystalline basement, Rodinia supercontinent, Caledonian events and c. The city was founded by Confederate General ‘Stovepipe’ Johnson in 1887. He was blinded in service, which led to Marble Falls being called the blind man’s town.Īside from its trivia, Marble Falls also has many interesting facets such as history, culture, hiking, natural areas, and water sports. Here are our favorite things to do in Marble Falls, Texas. It has a laid back, small town feel that you will instantly fall in love with.Īdmire the architecture in the Historic Downtown District and go looking for treasures in boutiques and antique stores on a self guided walking tour. If you love antique dolls, then you must visit the quirky Once Again Antique Dolls where you can find vintage dolls, toys, and even comics! Some of our favorite stores in the historic downtown area include Choccolatte for chocolates and Ms. Just walk along Main Street and step inside whichever shop you fancy: antiques, art galleries, and souvenir stores, all can be found here. Love artwork? Then you will love Sculpture on Main! You can also see the lake from Main Street, it’s a great place to walk around and explore. ![]() Located in the historic downtown, this public art gallery has an amazing variety of sculptures. It is a popular photo spot in the city and new sculptures are added every year. Marble Falls also has a great live music scene. You will find several spots for enjoying live music in and around Marble Falls. ![]() Whether you like jazz, blues, country or classic rock you will find something to your liking in the city.
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