Timothy John Barrington Holland FRS is a petrologist and Emeritus Professor in the Department of Earth Sciences at the University of Cambridge.^[3]

Holland was educated at the University of Oxford where he was awarded a Doctor of Philosophy degree in 1977^[1] for research on eclogites in the Tauern region of the Alps supervised by Stephen W. Richardson.^[2]

Holland's research investigates the computation of petrological phase equilibria.^{[2][4][5][6][7][8][9][10]} His research has been funded by the Natural Environment Research Council (NERC).^[11]

Holland has made fundamental and enduring contributions to petrology.^[12] He was the first to show that surface rocks had been buried to over 70 km.^[12] He has worked to construct a self-consistent thermodynamic database which describes equilibria among the multi-component mineral phases important in rocks and with full propagation of errors.^[12] This work, among the most highly cited in the geosciences, now underpins most petrological research.^[12] Recent advances include the calculation of mineral assemblages and compositions as a function of composition, pressure and temperature and the thermodynamic modelling of silicate melts, critical to tectonic interpretations of deeply buried rocks.^[12]