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Abstract: Trace element LA–ICPMS analyses of rutile from eclogites and veins from southwestern Tianshan, China, are carried out for testing the validity of Zr-in-rutile thermometry in low-T/UHP eclogites. Mineral inclusions in rutile and time-resolved mass spectrometer data are carefully examined to identify and reject contaminated data. The Zr contents vary between individual grains from the same sample; rutile inclusions in garnet, amphibole, and paragonite have a narrower range of Zr contents than matrix rutiles that always show the highest Zr contents, which reflects the progressive rutile growth in the eclogites. Average Zr concentrations in rutile from all six investigated eclogite samples statistically belong to one well-defined population (34±5ppm; 33±11ppm; 26±7ppm; 36±17ppm; 22±6ppm; 40±17ppm), while average Zr concentration in rutile from the three veins belong to a second well-defined population (55±7ppm; 66±6ppm; 55±5ppm). The peak temperature of eclogite can be estimated as 535–570°C at a pressure of 2.7GPa inverted from the discovery of well preserved coesite in an increasing number of rocks from southwestern Tianshan. The mineral assemblage of the veins suggests their retrograde formation in the epidote–amphibolite facies; the growth temperature of vein rutile is 530–540°C at ∼1.0GPa. A robust P–T path constructed by Zr-in-rutile thermometry in eclogites and veins indicates that the rocks underwent a rapid uplift involving an early isothermal decompression from eclogite to epidote–amphibolite facies. Zr in rutile from eclogites and veins can serve as a pressure indicator in study area that suggests the pressure has a significant effect to the Zr-in-rutile thermometry. [Copyright &y& Elsevier]

[Display omitted] • Large fracture-cavity reservoirs in fault damage zones are typically found at distances ranging from150 m to 800 m away from fault zone. • Reservoirs adjacent to the 'X' shear strike-slip fault are better developed. • Fault-controlled carbonate reservoirs are mainly formed in buried-hill karst stage. To reveal the effect of faults in the deep and ultra-deep oil and gas reservoirs, based on the comprehensive analysis of drilling logs and the core and seismic data, the development and fault-controlled regularity of the reservoirs in the high and low inner part of the Ordovician carbonate of the Tabei paleo-uplift have been discussed. The results show that large fracture-cave reservoirs are developed in the Tabei paleo-uplift, and as main reservoir, the cave-type reservoirs usually appeared as lumps or patches in the north of the pinch-out line of O 3 s , and gradually transitioned to isolated dots to the south. Due to the difference in control effect of faults, the degree of reservoir development differs greatly from north to south. The effective reservoir thicknesses are relatively stable and the porosity are relatively high in north, which are mainly controlled by karst and fractures, and the effect of faults on reservoir is not obvious. To the south, the reservoirs are gradually banded along the fault, and the control effect of large strike-slip faults are enhanced. This indicates that the strike-slip faults are more important to the development of reservoir in the low inner part. This difference is caused by the differences in fault controlling factors during different evolution periods of the paleo-uplift. [ABSTRACT FROM AUTHOR]