Evolution of terrestrial proto-CO2 atmosphere coupled with thermal history of the earth

Tajika, Eiichi; Matsui, Takafumi

doi:10.1016/0012-821x(92)90223-i

Cited by 95 publications

(74 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using Tice surface = -40'C and Tocean water = -20C gives an ice thickness of -1 km. On the early Earth, the heat flow was likely -3 ± 1 times greater than the present value (13,21). Thus, the ice thickness would have been only 300 ± 100 m.…”

Section: The Early Ocean Would Not Freeze Completelymentioning

confidence: 69%

“…The main sources and sinks of atmospheric CO2 on the early Earth are thought to be continental and sea floor weathering reactions and mantle degassing through hydrothermal vents (13,25). Although surface volcanoes are a significant source of atmospheric CO2 on the modern Earth, this source would have been much less important on the early Earth because of the small continental area.…”

Section: Periodic Thaw-freeze Cycles Associated With Impactsmentioning

confidence: 99%

“…This reduction could have been associated with the growth and weathering of continents (13), although it is uncertain whether there were any continents prior to 3.8 billion years ago (14). C02-rich atmospheres have been shown to be inefficient in the prebiotic synthesis of organic compounds (15,16).…”

Section: Introductionmentioning

confidence: 99%

“…For example, Kasting (8) states that "Atmospheric CO2 concentrations should have risen to whatever level was needed to keep the oceans from freezing and to balance the global C budget." High CO2 levels in the early atmosphere may have been the direct result of an impact-associated accretion process (13). However, impact erosion of the early atmosphere (19) could have resulted in atmospheric CO2 concentrations insufficient to prevent the formation of permanently frozen ocean.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Impact melting of frozen oceans on the early Earth: Implications for the origin of life

Bada

Bigham

Miller

1994

Proc. Natl. Acad. Sci. U.S.A.

131

View full text Add to dashboard Cite

Without sufficient greenhouse gases in the atmosphere, the early Earth would have become a permanently frozen planet because the young Sun was less luminous than it is today. Several resolutions to this faint young Sun-frozen Earth paradox have been proposed, with an atmosphere rich in CO2 being the one generally favored. However, these models assume that there were no mechanisms for melting a once frozen ocean. Here we show that bolide impacts between about 3.6 and 4.0 billion years ago could have episodically melted an ice-covered early ocean. Thaw-freeze cycles associated with bolide impacts could have been important for the initiation of abiotic reactions that gave rise to the first living organisms.

show abstract

Section: The Early Ocean Would Not Freeze Completelymentioning

confidence: 69%

Section: Periodic Thaw-freeze Cycles Associated With Impactsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Impact melting of frozen oceans on the early Earth: Implications for the origin of life

Bada

Bigham

Miller

1994

Proc. Natl. Acad. Sci. U.S.A.

131

View full text Add to dashboard Cite

show abstract

“…As a result, the tectonic activity and the continental area change considerably. Therefore, Tajika and Matsui (1992) have favored the so-called "global carbon cycle".…”

Section: Habitability Of Super-earthsmentioning

confidence: 99%

Habitability of Super-Earth Planets Around Other Suns: Models Including Red Giant Branch Evolution

et al. 2009

View full text Add to dashboard Cite

The unexpected diversity of exoplanets includes a growing number of super-Earth planets, i.e., exoplanets with masses of up to several Earth masses and a similar chemical and mineralogical composition as Earth. We present a thermal evolution model for a 10 Earth mass planet orbiting a star like the Sun. Our model is based on the integrated system approach, which describes the photosynthetic biomass production taking into account a variety of climatological, biogeochemical, and geodynamical processes. This allows us to identify a so-called photosynthesissustaining habitable zone (pHZ) determined by the limits of biological productivity on the planetary surface. Our model considers the solar evolution during the main-sequence stage and along the Red Giant Branch as described by the most recent solar model. We obtain a large set of solutions consistent with the principal possibility of life. The highest likelihood of habitability is found for "water worlds". Only mass-rich water worlds are able to realize pHZ-type habitability beyond the stellar main-sequence on the Red Giant Branch.4

show abstract

Water circulation and global mantle dynamics: Insight from numerical modeling

Nakagawa

Nakakuki

Iwamori

2015

Geochem Geophys Geosyst

View full text Add to dashboard Cite

We investigate water circulation and its dynamical effects on global-scale mantle dynamics in numerical thermochemical mantle convection simulations. Both dehydration-hydration processes and dehydration melting are included. We also assume the rheological properties of hydrous minerals and density reduction caused by hydrous minerals. Heat transfer due to mantle convection seems to be enhanced more effectively than water cycling in the mantle convection system when reasonable water dependence of viscosity is assumed, due to effective slab dehydration at shallow depths. Water still affects significantly the global dynamics by weakening the near-surface oceanic crust and lithosphere, enhancing the activity of surface plate motion compared to dry mantle case. As a result, including hydrous minerals, the more viscous mantle is expected with several orders of magnitude compared to the dry mantle. The average water content in the whole mantle is regulated by the dehydration-hydration process. The large-scale thermochemical anomalies, as is observed in the deep mantle, is found when a large density contrast between basaltic material and ambient mantle is assumed (4-5%), comparable to mineral physics measurements. Through this study, the effects of hydrous minerals in mantle dynamics are very important for interpreting the observational constraints on mantle convection.

show abstract

Evolution of terrestrial proto-CO2 atmosphere coupled with thermal history of the earth

Cited by 95 publications

References 33 publications

Impact melting of frozen oceans on the early Earth: Implications for the origin of life

Impact melting of frozen oceans on the early Earth: Implications for the origin of life

Habitability of Super-Earth Planets Around Other Suns: Models Including Red Giant Branch Evolution

Water circulation and global mantle dynamics: Insight from numerical modeling

Contact Info

Product

Resources

About