Phanerozoic Time - the Cenozoic

During this period (the last 65 million years), the world began to take on broadly the landforms and landscapes more or less as we know them today, i.e. the basic engineering geology environment of the regions began to form.

In the Americas the Cordilleran orogenesis was complete during Palaeocene and Eocene times, when the Rocky and Andes Mountains were formed by compression of Palaeozoic or Mesozoic strata. Inter-mountain basins were then filled with river and lake deposits, scattered granites and ore deposits were also produced during tectonic episodes.

Regional up-warping during the late Cenozoic (mainly Neogene) times rejuvenated rivers in the Rocky Mountain-Colorado Plateau region, resulting in deep canyon cutting. Extension and transform movements of the crust of the westernmost parts of North America characterised Neogene times in contrast with the compressional tectonics of Palaeogene times and caused:

A passive continental margin coastal plain and the deposition of continental shelf strata succeeded many of the former tectonically active Palaeozoic margin structures.

The Gulf of Mexico Province is now underlain by the thickest sequence of any passive margin and is characterised by abundant rising salt domes, which produced important petroleum traps: the Arctic Province also possesses evaporite domes reflecting the dramatically different hot climate that existed during sediment deposition, in contrast to today's cold one. The Atlantic Coast Province of Northern America also experienced a rejuvenation of the Appalachian Mountains by crustal up-warping and river down-cutting.

The Pacific Ocean region underwent major changes from Palaeogene to Neogene times.

The distribution of equatorial sediments and the track of the Hawaiian mantle plume indicate a change of Pacific plate motion about the same time that California collided with an ancient ocean ridge.

Eurasia experienced major late Cenozoic tectonic events, viz.:

Australia is currently on a collision course with the Indonesian Arc and ultimately with south east Asia, converging at the rate of some 6 cm/year.