Tertiary period

The principal marine deposits were formed during the Tertiary period and more particularly the upper Miocene epoch. Deposits of freshwater origin date from the PHocene to Miocene epochs to more recent times, dating to as late as 100,000 years ago. U.S. commercial deposits are at or comparatively near the surface. Bog deposits are exploited and lake beds are dredged for use in other parts of the world. 

Speleothems and other secondary carbonate deposits such as tufa, travertines, lake carbonates and vein calcites have the potential to provide valuable information about past climate, hydrogeochemistry, landscape development and hominid evolution during the early Quaternary and Tertiary periods. Electron-spin resonance (Griin 1989, Rink 1997) and disequilibrium methods (Ludwig et al. 1992) have proved to be useful in... 

In Gubbio, Italy, a 1 cm layer of clay between extensive limestone formations marks the boundary between the Cretaceous and Tertiary Periods. This clay layer was known to have been deposited about 65 million years ago when many life forms became extinct, but the length of time associated with the deposition was not known. In an attempt to measure this time with normally deposited meteoritic material as a clock, extensive measurements of iridium abundances (and those of many other elements) were made on the Gubbio rocks. Neutron activation analysis was the principal tool used in these studies. About 50 elements were searched for in materials like the earth s crust, about 40 were detected and about 30 were measured with useful precision [26-28]2. 

During the Tertiary period which dates back approximately 65 million years. Deposits include the sub-bituminous coal and lignite beds in the Great Plains Province, which includes northeastern Wyoming, eastern Montana, western North Dakota, and northwestern North Dakota. 

With the exception of burmite all the ambers mentioned so far are from the Tertiary period. There are many finds of amber from the Cretaceous period, 140 to 65 million years ago, but the vast majority of these are of little use as decorative material as they are far too brittle to work. They are usually found in very small pieces and tend to be a dull, opaque brown. They are, however, of great scientific interest, especially as some contain plant and animal inclusions. 

Amber is by no means a uniform substance, but a mixture of resins. Most of it was formed in the tertiary period, an era which began about 65 million years ago and ended about 2 million years ago. The resin exudated by the plants attracted insects which were trapped by the sticky mass. Thus the inclusion of these insects and plants gives palaeontologists the rare possibility of studying extinct life forms in their natural state. About a thousand types of insects have been discovered in amber, which is mainly found on beaches in East Prussia. ... 

Eocene. An epoch of the lower Tertiary period of the geologic time scale commenced approximately 54 million years ago. 

The most important deposits were formed in the Devonian, Carboniferous, Permian, Cretaceous, and Tertiary periods. All major deposits are of marine origin. 

Thus, the evolution of the gaseous envelope of the Earth was an extraordinarily compact dynamic process, which has taken several milliard years and which is still continuing. The dynamic character of this process is also supported by the fact that particular components do not occur permanently in the atmosphere — they only pass through it. The development was very slow (the composition of the earth s atmosphere has remained essentially unaltered from the beginning of the Tertiary period) and thus, it is reasonable to assume that the earth s gaseous envelope is in the state of dynamic equilibrium. 

During the Tertiary period continental movements resulted in the opening of the North Atlantic. Scandinavia rose to become a pronounced highland, where rivers transported clay and sand out to the sea. These deposits created floody plains and delta plains that led to the Danish area being above the sea level. 

Amber (succinite). General term for fossilized terpenoid resins from the Tertiary period formed from resinous secretions of coniferous trees. They owe their hardness and poor solubility to the evaporation of volatile terpenes as well as to autoxidation and polymerization of resin acids and alcohols. The resin alcohols are mostly esterified with succinic acid. - [HS253090]... 

Since the first human-like primates (hominids) evolved during the Tertiary Period, it is reasonable to assume from a phylogenetic viewpoint that malaria parasites have accompanied mankind aU along its development path. Plasmodium falciparum is thought to have been transmitted to humans initially from gorillas. [412] But presumably, malaria epidemics might have occurred only some 10,000 years ago, when humans settled down and started farming. 

Antarctica truly is the land of fire and ice because it contains a large number of volcanoes that were active during the Tertiary Period (LeMasurier 1990). At the present time only Mt. Erebus on Ross Island in Fig. 2.2a, b is still active. The summit of Mt. Erebus,... 

Miocene followed by another decline at 10.8 Ma to -100 m. The authors cautioned that the rapid lowering of sea level during the Tertiary Period is controversial but concluded (Vail and Hardenbol 1979, p. 79) ... 

Coal formation continued throughout the Permian, Triassic, Jurassic, Cretaceous, and Tertiary Periods (known collectively as the second coal age), which spanned 290 to 1.6 million years before present. During that time, coal formation started from thick layers of dead plants that piled up in ancient swamps. The dead plant layers were buried deeper and deeper under even thicker layers of sand and mud. During burial, pressure and heat changed the plant material into coal. Coal from the western United States usually formed during or after the era of the dinosaurs (about 50-100 million years ago). 

Another maceral of the inertinite group is sclerotinite, which is the result of fungal remains. Sclerotinite occurs as ovoid bodies with cell structure, with reflectance covering the entire inertinite range. Sclerotinite is found mainly in coals of the Tertiary Period, particularly in the lignites, and also in bituminous coals of the Paleozoic era. Sclerotinite (Figure 4.3) is opaque, highly reflective, and, in the oval or round form, may vary in size from 20 to 300 pm (30 to 300 x 10 mm). 

France - The Tertiary Period (Oligocene Epoch) Alsace-Wittelsheim potash deposit in France contains two potash beds separated by about 20 m of halite. The lower bed is found in an area of about 300 km and is 1-5 m thick the ore contains 12%-20% K2O. The upper bed covers an area of 115 km it averages 1.5 m in thickness, and the ore contains 20%-27% K2O. The potash content of the beds diminishes to less than 11% at their edges, where they thin to 1 m or less. The beds are found at depths of 420-1,800 m, and they dip slowly and variably to the north-northeast at 0 -25°. To the east of the Wittelsheim deposit, and separated by the... 

In southern Asia, the Andropogoneae (Sorghum, Zea, Saccharum, Bothriochloa, Imperata) developed from some C4 ancestor and rapidly occupied savanna habitats and dry open woodlands. It is supposed that this occurred some 25-30% Mya (million years ago). Andropogonoid species form 30-40% of all grass species in India and Africa. The transfer of Andropogoneae to America probably occurred via southern Europe, before their separation in the Tertiary period while they probably reached Australia via island chains. 

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