Detailed reconstructions of India-Somalia plate motion, 60 Ma to present: Implications for Somalia plate absolute motion and India-Eurasia plate motion

Summary We estimate India-Somalia plate motion at 45 times since 60 Ma from ?9,000 crossings of Carlsberg and northern Central Indian Ridge magnetic reversals C1 to C26 numerous fracture zone crossings. The new rotations reveal least seven significant spreading rate changes ?60 Ma, some previously unknown. largest occurred before 46 when the forces acting on India evolved rapidly due transition subduction continent-continent collision between Asia influence Reunion hotspot plume plate. a gradual ?50 percent decline in rates 57-52.7 but an end ?53 surged by up 100 percent. From 52-46.7 collapsed ?90 percent, possibly defining protracted continental Asia. Significant kinematic events 46.7 have included ?25 recovery 42-40 ultraslow 38.6-33.2 doubling 33-18 slowdown 18-13 apparently steady 13 Ma. successfully predict abyssal hill orientations for seafloor ages 48-42 20-0 traces 43 16 constituting useful tests rotation accuracies these ages. When corrected movement relative Capricorn also restore lineations C13, C18, C20, C21, segments onto their Somalia counterparts. This further confirms our back C21n.1o (47.8 Ma), validates ?16 start date India-Capricorn published correction motion. Anticorrelated Antarctic-Somalia 37-18 may be evidence that absolute changed during this period, triggered Somalia’s post-30-Ma detachment Arabian Peninsula or effects Afar and/or mantle plumes New India-Eurasia we updated global circuit convergence 53-47 are ?30 faster than previous estimates ?75 ?38 Changes correspond closely with recently described Tibetan deformation pulses, consistent linkages all three. A joint inversion southern ridge reversal data, including India, satisfactorily realigns reconstructed zones C23n.1n (50.7 misfits data km more earlier times. within IndoCapricorn plates 48 misinterpretation