This list provides references to notable

unsolved problems List of unsolved problems may refer to several notable conjectures or open problems in various academic fields: Natural sciences, engineering and medicine * Unsolved problems in astronomy * Unsolved problems in biology * Unsolved problems in c ...

geoscience Earth science or geoscience includes all fields of natural science related to the planet Earth. This is a branch of science dealing with the physical, chemical, and biological complex constitutions and synergistic linkages of Earth's four spheres ...

The early Earth and the solar system

* Was there ever a collision of the Earth with another planet

Theia In Greek mythology, Theia (; grc, Θεία, Theía, divine, also rendered Thea or Thia), also called Euryphaessa ( grc, Εὐρυφάεσσα) "wide-shining", is one of the twelve Titans, the children of the earth goddess Gaia and the sky god ...

, giving birth to our satellite? There is compelling evidence, such as measures of a shorter duration of the Earth's rotation and lunar month in the past, pointing to a Moon much closer to Earth during the early stages of the Solar System. * What is the long-term heat balance of Earth? How did its internal temperature decay since it formed by accretion of chondrites? How abundant are radiogenic elements in the interior? Did a " faint young Sun" ever warm a "

snowball Earth The Snowball Earth hypothesis proposes that, during one or more of Earth's Greenhouse and icehouse Earth, icehouse Climate, climates, the Earth's surface, planet's surface became entirely or nearly entirely Freezing, frozen. It is believed that ...

Topography and environment

*Can the now widely available topographic data be used to derive past tectonic and climatic conditions (in the multi-million year scale)? Do we know enough about the erosion and transport processes? Does the stochasticity of meteorological and tectonic events reflect in the landscape? How much has life contributed to shape the Earth's surface? *Can classical geomorphological concepts such as peneplanation or

retrogressive erosion Headward erosion is erosion at the origin of a stream channel, which causes the origin to move back away from the direction of the stream flow, lengthening the stream channel.Essentials of Geology, 3rd Ed, Stephen Marshak It can also refer to ...

be quantitatively understood? Old mountain ranges such as the Appalachian or the Urals seem to retain relief for >10⁸ years, while subglacial fluvial valleys under Antarctica are preserved under moving ice of kilometric thickness since the

Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...

. What controls the time-scale of topographic decay? *What are the erosion and transport laws governing the evolution of the Earth's Surface? Rivers transport sediment particles that are at the same time the tools for erosion but also the shield protecting the bedrock. How important is this double role of sediment for the evolution of landscapes? *How resilient is the ocean to chemical perturbations? *What controls the dynamics of storm tracks? * Mechanisms that cause oscillations in equatorial climate remain under intense study. The El Nino Southern Oscillation ( ENSO) of the equatorial Pacific Ocean temperature is difficult to predict more than a few months in advance. The Quasi-Biennial Oscillation ( QBO) of the equatorial stratospheric winds is somewhat regular at ~28 months but the cause has been heavily debated. Are these stochastic, chaotic, or deterministically forced behaviors? * What are

skyquake A skyquake is a phenomenon where a loud booming sound is reported to originate from the sky. The sound may cause noticeable vibration in a building or across a particular area. Those who experience skyquakes typically do not have a clear explanati ...

s? * What causes

Hessdalen lights The Hessdalen lights are unidentified lights observed in a stretch of the Hessdalen valley in rural central Norway. Background The Hessdalen lights are of unknown origin. They appear both by day and by night, and seem to float through and abov ...

Structure of crust, mantle, and core

*The 'space problem': How are granite magma chambers emplaced in the crust? What are the structures and locations of the magmatic systems that might cause

supervolcano A supervolcano is a volcano that has had an eruption with a Volcanic Explosivity Index (VEI) of 8, the largest recorded value on the index. This means the volume of deposits for such an eruption is greater than 1,000 cubic kilometers (240 cubic ...

es? What are the viscosities and densities of the magma chambers and the details of magma migration? *What are the non-uniformities and rheological details of the mantle? What is the structure of the 660 km discontinuity and its relation to the correct model of the

polar drift Polar drift is a geological phenomenon caused by variations in the flow of molten iron in Earth's outer core, resulting in changes in the orientation of Earth's magnetic field, and hence the position of the magnetic north- and south poles. The N ...

? *What is the precise nature of chemical heterogeneity associated with the Gutenberg discontinuity? *What are the light alloying elements in the Earth's outer core and how are they distributed? What are the heterogeneities of the core and their dynamical significance? *Does the internal mantle structure provide the resonance for the

Chandler wobble The Chandler wobble or Chandler variation of latitude is a small deviation in the Earth's axis of rotation relative to the solid earth, which was discovered by and named after American astronomer Seth Carlo Chandler in 1891. It amounts to change o ...

of the earth's axis or is it some other external mechanism? No available motions seem to be coherent drivers for the wobble period of 433 days.

References

External links

* {{Unsolved problems

Unsolved problems List of unsolved problems may refer to several notable conjectures or open problems in various academic fields: Natural sciences, engineering and medicine * Unsolved problems in astronomy * Unsolved problems in biology * Unsolved problems in c ...

Geoscience Earth science or geoscience includes all fields of natural science related to the planet Earth. This is a branch of science dealing with the physical, chemical, and biological complex constitutions and synergistic linkages of Earth's four spheres ...