What Are the Different Types of Paleontology Programs?

Paleontology, a branch of geology, is a cross-science of life sciences and earth sciences. It is not only a unique branch of life sciences with a time scale of historical scientific nature, it is an important foundation and component of the study of historical biology such as the origin of life, development history, biological macro-evolution models, rhythms and action mechanisms; Branch to study the biological remains, relics, and fossils preserved in the stratum to determine the sequence and age of the stratum, understand the history of crustal development, and infer the laws of formation and distribution of water and land distribution, climate change, and sedimentary minerals in geological history.

According to the different objects studied, paleontology is divided into

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Paleontology are creatures of the earth's history, and also follow

Traditional paleontology focuses on

Paleontology has the dual task of serving geology and biology.

Palaeontology serves geology

Establishing a stratigraphic system and a representative geological year: This is the most widely used and effective aspect of paleontology in geology. According to the stratigraphic sequence law, the progressiveness, phase, and irreversibility of biological evolution. After decades of efforts, the stratigraphic system and the corresponding geochronological system from the Precambrian to the Quaternary were established in the 19th century. Although radiometric dating and other methods have been developed since the 20th century, biostratigraphy is still the main method for establishing stratigraphic units at all levels. The stratigraphic units corresponding to the middle ages, epochs, epochs and periods of the geological age are boundary system, ancestry, and stage. For example, the prosperous age of reptiles, gymnosperms, and chrysanthemums were classified as Mesozoic, in which the period when the dinosaurs and chrysanthemums were most prosperous was the Jurassic; the early Jurassic period was Eode-rocerataceae and Psilocerataceae. The family is characterized by the Sanomanian period. In the future, several chrysanthemum belts can be divided.

Division of paleontology and contrasting strata

This research is called biostratigraphy. Of the biostratigraphic methods, the oldest is the standardized stone method. Standardized stones must have the following conditions: the geological age is short in order to accurately determine the age of the stratum; the geographical distribution is extensive so that it can be easily found and can be compared on a large scale. For example, the aforementioned white sheep stone, which can be found in the ancient Mediterranean regions throughout Europe and Asia, is a standardized stone of the Sanomanian order. When using standardized stone methods, it should be noted that any fossil has a process that occurs in time, flourishes, is rare, and becomes extinct, and that it originates, migrates, and disperses in space. The epoch and geographical distribution stipulated in the predecessors and the literature need to be modified according to the specific circumstances, and can not be moved rigidly. It should also be noted that the various types of fossils in a biome have varying degrees of stratigraphic significance. The appearance of the entire biome cannot be ignored, and the stratigraphic age can only be determined based on a few standardized rocks.

In addition to the standardized stone method, the percentage statistical method, etc., the comparison method, the quantity (or graphic) comparison method, and so on.

Restoration of paleogeography and paleoclimate. As a result of adaptation to the environment, various organisms have characteristics that reflect environmental conditions in their habitual behavior and body shape and structure. Therefore, after the form, classification and ecology of the fossils have been clarified, the living environment during their survival period can be inferred by applying the method of "contemplating the ancients". Particularly useful in this regard are facies fossils, that is, fossils that clearly indicate a certain sedimentary environment. For example, the living environment of reef-building corals is the ocean, the water depth does not exceed 100 meters, the water temperature is above 18 ° C, the sea water is clear, and the water flow is calm. Therefore, if a coral reef is found in the formation, it can be judged that its depositional environment is a warm, clear shallow sea. Another example is that ferns live in a warm and humid climate, so the discovery of a large number of fern fossils in the stratum indicates that the ancient climate at that time was warm and humid. When using fossils to restore the paleoenvironment, it should be noted that many living things have evolved in the living environment during the period of geohistory. For example, sea lily was a typical shallow sea animal in the Paleozoic era, and most of them now live in the deep sea. In addition, not only refers to facies fossils, but also the various types of biota and the sediments themselves have environmental significance, and comprehensive analysis must be paid attention to.

Study the genesis and distribution of sedimentary rocks and sedimentary minerals: Many sedimentary rocks, such as some limestone and diatomaceous earth, are mainly composed of fossils, especially energy minerals (petroleum, oil shale, coal) are mainly formed by animal and plant remains. The main application of paleontology in ore prospecting are as follows: study the distribution of minerals according to the epochal distribution and ecological characteristics of mineralized fossils; widely use micro- and ultra-micro fossils, accurately divide and contrast ore-bearing horizons, and guide Drilling, etc .; From the perspective of paleobiochemistry, study the law of paleontium enrichment of rare metal elements by means of adsorption, complexation, compounding, etc .; study the role of archaebacteria in mineral formation, etc.

Applications in geophysics, geochemistry, and tectonic geology: Changes in the rotation speed of the earth cause changes in living conditions of the organism, which are reflected as changes in biological form and structure. The paleontology clock uses the characteristics of the biological growth cycle to calculate the change of the earth's rotation speed during the geohistory period. For example, in the past year, modern corals had about 360 circles of fine lines, each line representing a day. On Devonian coral fossils, the growth of fine lines is about 400 circles, and that of the Carboniferous is 385 to 390 circles, indicating that the number of days at that time was about 400 and about 385 to 390, respectively. The number of days per year is roughly the same. Similar conclusions can be drawn from the growth line studies of the bivalvia, cephalopod, gastropod, and stromatolites. Calculations show that since the Cambrian, the number of days per year and month has gradually decreased, indicating that the earth's rotation speed is slowing down.

In structural geology, the shape and orientation of strained ellipsoids are obtained by comparing the deformed fossils (brachipods, pen stones, trilobites) with similar undeformed fossils.

Regarding the theory of plate tectonics, there are also examples of paleontology, such as the division of the southern continent, where the fossils of the freshwater reptile Mesosaurus can be found on both sides at the same time. In the study of a series of microplates or terranes, the relevant paleontological fossils should be used as a basis for comparison.

Palaeontology is of great significance in studying the strata formed by deep-sea sediments. ^[1]