Impact of Grassland Radiation on the Nonmarine Silica Cycle and Miocene Diatomite

  title={Impact of Grassland Radiation on the Nonmarine Silica Cycle and Miocene Diatomite},
  author={David L. Kidder and Elizabeth H. Gierlowski-Kordesch},
Abstract The Early Miocene rise of the grass-dominated ecosystem is a plausible trigger for a sharp Miocene increase in accumulation of nonmarine diatomaceous sediment as well as diversification of nonmarine diatoms. This grassland radiation introduced a biogeochemical mechanism for enhancing widespread and sustained mobilization of usable silica and other nutrients. Volcanism was probably responsible for episodic nonmarine diatomaceous sediments from the advent of the oldest known nonmarine… 

The turnover of continental planktonic diatoms near the middle/late Miocene boundary and their Cenozoic evolution

The turnover from nonmarine Actinocyclus to Stephanodiscaceae genera near the middle/late Miocene boundary may be linked to a contemporaneous increase in silica concentrations in lakes caused by active volcanism, increased weathering of silicate rocks due to orogeny, and the expansion of C4 grasslands.


Abstract Despite the rise of marine diatoms in the world's oceans throughout the Cretaceous, only a handful of fossil localities worldwide detail invasion of freshwater habitats by diatoms commencing

Diversity dynamics of marine planktonic diatoms across the Cenozoic

Recon reconstructions of species diversity in marine phytoplankton reject proposed biotic controls on diversification and suggest a new pattern for oceanic diatom diversity across the Cenozoic.

The impact of neogene grassland expansion and aridification on the isotopic composition of continental precipitation

The late Cenozoic was a time of global cooling, increased aridity, and expansion of grasslands. In the last two decades numerous records of oxygen isotopes have been collected to assess plant

DIATOM METHODS/Quaternary Geological Records

  • R. Flower
  • Environmental Science, Geography
  • 2007

The onset of grasses in the Amazon drainage basin, evidence from the fossil record

Poaceae (the grass family) originated in the Cretaceous, but first dominate the palynological records of the Amazon drainage basin (ADB) in the Neogene (23 to 2.5 million years ago (Ma)). However,

Evolution of Grasses and Grassland Ecosystems

The evolution and subsequent ecological expansion of grasses (Poaceae) since the Late Cretaceous have resulted in the establishment of one of Earth's dominant biomes, the temperate and tropical

The rise to dominance of lanternfishes (Teleostei: Myctophidae) in the oceanic ecosystems: a paleontological perspective

Abstract. Lanternfishes currently represent one of the dominant groups of mesopelagic fishes in terms of abundance, biomass, and diversity. Their otolith record dominates pelagic sediments below 200



Grasslands, silicate weathering and diatoms: Cause and effect

Diatoms are silica-limited, photosynthetic, single-celled eukaryotes that today occupy a wide variety of habitats both in freshwater and marine environments. Ultimately the silica they use is derived

Cenozoic Expansion of Grasslands and Climatic Cooling

Mountains, ocean currents, forests, and swamps have played an important role in regulating global climate for hundreds of millions of years, but the truly novel event of the Cenozoic was the

Diatoms and tonsteins as paleoenvironmental and paleodepositional indicators in a Miocene coal bed, Costa Rica

Fresh-water diatoms are present in coal, and tonsteins (altered volcanic ash) are interbedded with the coal, in the Miocene Venado Formation on the southwest margin of the Limon Basin, in Provincia

Secular Distribution of Biogenic Silica through the Phanerozoic: Comparison of Silica‐Replaced Fossils and Bedded Cherts at the Series Level

The modern marine silica cycle is dominated by silica‐secreting phytoplankton, principally diatoms, but this cycle has evolved considerably during the Phanerozoic. We analyzed the temporal

On the Miocene Non-marine Diatomite in the Vicinity of Nakajima-machi, Noto Peninsula, Japan

The Yamatoda diatomaceous mudstone member (10∼15 m thick), which is characterized by the dominance of freshwater diatoms, unconformably overlies a two-pyroxene andesite and its agglomerates (Anamizu

Miocene Brackish Water and Lacustrine Deposition in the Suez Rift, Sinai, Egypt

Abstract From its inception during the early Miocene, the Suez Rift has been dominated by marine sedimentation. New high-resolution biostratigraphic and sedimentologic analyses of synrift deposits

Evolution of Lacustrine Diatomite Carbonate Cycles of Miocene Age, Southeastern Spain: Petrology and Isotope Geochemistry

ABSTRACT Continental formations of Miocene age outcropping in southeastern Spain include beds of diatomites (in economic quantities) irregularly alternating with carbonate beds. The minerology and

Paleoenvironmental significance of a new species of freshwater sponge from the Late Miocene Quillagua Formation ( N Chile )

This paper reports the first fossil (Tertiary) occurrence of freshwater sponges of the genus Ephydatia in the southern hemisphere. The sponges appear in diatomite lacustrine sediments of Late Miocene