  Turbulent and internal wave motions are important for the exchange of
momentum, heat and suspended matter in the deep-sea which is generally stably
stratified in density. Turbulence-generation models involve shear of vertical
current differences that deforms the stratified waters, and convection that is
drive by (unstable) buoyancy. Shear-generation is found more general in the
well-stratified ocean-interior, while convection is known to occur near the
sea-surface, e.g. via nighttime cooling. Far below the surface, the
Western-Mediterranean Sea is very weakly stratified and offers opportunity to
observationally study deep-sea convection. An opportunistic small set of
high-resolution temperature sensors demonstrates not only classic
internal-wave-induced turbulence, but also convection attributed to geothermal
heating and spectral properties that relate to various chaos-theory models such
as 1/sigma pink noise (sigma denoting frequency), mainly found lying at (0.01 m
above) the seafloor, and 1/sigma^2 Brownian noise, mainly found on a moored
line at about 100 m above the seafloor. Near-inertial temperature variations
are observed to occur down to the seafloor thereby disturbing the local
convective turbulence regime to shear-dominated one temporarily. The integral
turbulence time-scale is generally smaller (with dominant higher frequency
motions) at the seafloor than about 100 m above it.
