Paleoclimate indicators derived from terrestrial sediments, on the other hand, are commonly influenced by local tectonic movements and paleogeographic variations.
Global paleoclimate indicators are established based on the information extracted from the analyses of geologic materials, including biological, geochemical and mineralogical data preserved in marine sediments.
[citation needed] Because of their widespread distribution and abundance in sediments, forams have been the most extensively explored for their biological characters linked to paleoclimatic and paleoecologic reconstructions.
[7] Globigerina bulloides, a benthic foram, has been documented for its coiling directions related to seawater temperatures in surface sediments of the southern Indian Ocean.
Among the early pioneers to apply foraminifera latitudinal abundances, Ericson and Wollin (1968) succeeded in establishing the Pleistocene glacial and interglacial cycles based on the ratios of cold and warm water species in tropical sediments.
A climatic curve in the Oligocene was constructed in the Gulf of Mexico by using warm water indicators (Turborotalia pseudoampliapertura, Globoquadrina tripartita, Dentoglobigerina globularis, Dentoglobigerina baroemoenensis, “Globigerina” ciperoensis and Globigerinoides groups, and Cassigerinella chipolensis) and cold water indicators (Catapsydrax spp., Globorotaloides spp., Subbotina angiporoides group, Globigerina s.
[13] A more extensive geographic coverage was investigated by Spezzaferri in 1995, who analyzed samples from drilling cores in the Atlantic, Indian and South Pacific Oceans and identified and grouped foraminifera into warmer, cooler, warm-temperate and cool-temperate indices.
Thompson (1981) was able to relate six foraminiferal assemblages from core top samples to present water masses in the western North Pacific.
[15] Similar technique has been applied to the Eocene and Oligocene sediments and the forams have been categorized in surface, intermediate and deep water-mass groups.
Study of Radiolarians in the North Pacific deep sea cores has revealed that increases in both species diversity and abundance correspond to major glaciation events of the last 16 million years.
Not only their indicator species, but also the trace element and stable isotope geochemistry of their shells have been documented as evidence of past climate fluctuations.
For instance, Shackleton and Kennett (1975) have established the Cenozoic paleotemperature history based on analyzing oxygen isotope composition of both planktonic and benthic foraminifera in the Antarctic region.
The Surface temperature fluctuation from the Paleocene to Miocene has been established based on carbon isotope data from foraminifera in Antarctic region.
[25] The organic matter preserved in sediments records paleoecosystems, and its carbon isotope composition has been also utilized to reconstruct paleoclimatic evolution.
For example, Rogers and Koons (1969) have reported that the carbon isotope ratios, derived from organic matter in Quaternary marine sediments in the Gulf of Mexico, correlate well with Pleistocene climate changes.
[28] Other sources for organic carbon isotope used as proxies for paleoenvironment reconstruction include lacustrine deposits for lake level variations,[29] fossilized vertebrates for precipitation fluctuations,[30] oil shales for paleoecological and paleoclimate conditions.
Huang et al. (2017), for example, based on the distribution of Permian ooids and glaciomarine diamictites, have repositioned the Baoshan Block in southwestern China, with respect to other Gondwana continents.