Abstract
The differential geometry of tangent bundles was studied by several authors, for example: D. E. Blair, E. T. Davies, P. Dombrowski, S. Ianus, A. J. Ledger and K. Yano, V. Oproiu, C. Udriste, Yano and Davies, Yano and Ishihara and among others [15, 23, 24, 25, 26]. It is well known that different structures defined on a manifold M can be lifted to the same type of structures on its tangent bundle. However, when we consider the generalized almost r-contact structure not the same type of structure is obtained on the tangent bundle. The aim of this study is to investigate the prolongations of G-structures immersed in the generalized almost r-contact structure on a manifold M to its tangent bundle T(M). Moreover, An almost contact structure, Lorentzian almost paracontact structure etc. on the tangent bundle T(M) are discussed.