Biomarker characteristics of Montney source rock, British Columbia, Canada.

Montney Formation (MF) source rock located in northeastern British Columbia (BC), Canada, was analyzed to determine its depositional conditions and organic matter source input other than to determine their level of thermal maturity. The high total sulfur (TS) (2.23-20.86 wt.%) and good to very good total organic carbon (TOC) content (0.3-5.87 wt.%) in the analyzed samples give good evidence that the deposition of MF source rock was in a marine environment under reducing conditions. A mixed marine-terrestrial derived organic matter (OM) for the Montney source rock that was deposited in a marine dysoxic environment is deduced from the composition and distribution of different biomarker traces. Thus, the previous result is supported by the high short-chain n-alkanes ratio, accompanied by carbon preference index (CPI) around unity, high concentration of tricyclic terpanes, high C24 tricyclic/C24 tetracyclic, hopane/sterane ratios ranging from low to moderate, as well as the relationship between regular sterane compositions. During deposition of the MF source rock, it can be noticed that more land organic materials this was deduced according to the high waxiness index. From maturity ratios of Ts/(Ts + Tm), C32 22S/(22S + 22R) homohopane, moretane/hopane and 20S/(20S + 20R) and ßß/(ßß + αα) C29 it can give a conclusion that the source rock is mature to postmature of hydrocarbon generation.

Density estimation based on the Hounsfield unit value of cone beam computed tomography imaging of the jawbone system.

The aim of this study is to investigate the estimation of density from the Hounsfield unit of cone beam computed tomography data in dental imaging, especially for dental implant application. A jaw phantom with various known densities of anatomical parts (e.g. soft tissue, cortical bone, trabecular bone, tooth enamel, tooth dentin, sinus cavity, spinal cord and spinal disc) has been used to test the accuracy of the Hounsfield unit of cone beam computed tomography in estimating the mechanical density (true density). The Hounsfield unit of cone beam computed tomography data was evaluated via the MIMICS software using both two-dimensional and three-dimensional methods, and the results showed correlation with the true density of the object. In addition, the results revealed that the Hounsfield unit of cone beam computed tomography and bone density had a logarithmic relation, rather than a linear one. To this end, the correlation coefficient of logarithmic correlation (R2 = 0.95) is higher than the linear one (R2 = 0.77).