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Goro Komatsu
Research Professor
EXAMPLES OF RESEARCH ACTIVITIES
Geology of Mars
1. Ancient oceans and lakes
Whether Mars had large bodies of liquid water on its surface in the past is one of the most fascinating topics
of Mars geology. The issues to be considered are not only the presence of oceans and lakes, but also their
implications for the climate and resulting landforms. Works on searching for possible evidence of ancient
oceans and lakes (e.g., shoreline features, geochemical signatures) are also in progress.
2. Outflow channels
Cataclysmic flooding is one of my lifetime research interests. We have studied geological features on Mars
that were probably formed by floods of extraordinary scales, including Ares Vallis where
the Mars Pathfinder landed in 1997. We have also identified possible evidence for glacial or peri-glacial
episodes following the catastrophic flooding.
3. Possible glacier and peri-glaical landforms
The new high-resolution images of Mars have revealed a type of geological features that have never been
or rarely observed before by the previously obtained Viking data. We conducted mapping investigations in the
Hellas basin and its vicinity and found many features best interpreted to be ice related. We have also
indentified and interpreted mounds in the Utopia basin as peri-glacial landforms (i.e., pingos).
4. Interior layered deposits in Valles Marineris
Interior layered deposits are present extensively in Valles Marineris, a great canyon system in the equatorial
region of Mars. There have been a number of origins proposed, including eolian, lake sediments, volcanics,
etc. We analyzed their detailed geomorphology and stratigraphy.
5. Sedimentary deposits and exobiology
When we explore Mars in search for life, some of the most promising geological materials are sedimentary
deposits. This is due to the fact that many types of sedimentary deposits on Earth are formed by biological
processes and also a number of sedimentary deposits are known to preserve biological materials within. We
assessed representative sedimentary deposits for their exobiological potentials.
6. Groundwater activities
Mars is probably a planet characterized not only by its past surface water processes but also by
groundwater processes. Some features on Mars may be linked with groundwater
movements. We have been investigating such features that have been interpreted to be
concretions, discoloration along deformation bands, and cemented knobs/injection pipes. An extensive and
long-term project utilizing a wide variety of terrestrial analogs in Utah is currently ongoing.
7. Ejecta emplacement of Martian impact craters
Martian impact craters are characterized by ejecta layers that are morphologically different from those
associated with impact craters on the airless and dry Moon. We investigated their geomorphological
characteristics utilizing a variety of remote sensing data including DEMs derived from the HRSC stereo
camera.
8. Geological processes involving methane and/or carbon dioxide gases
Gasses such as methane and carbon dioxide may have played important roles in geological processes of Mars.
We have been assessing such processes and also searching for landforms which may have involved
these gasses (e.g., mud volcanoes).
Geology of Venus
1. Channels and valleys
As a science team member of the Magellan mission to Venus in the early 1990s', I worked on the enigmatic
channels and valleys on the planet. These are landforms that mimic terrestrial fluvial rivers and valleys
in terms of the range of morphology. The Venus environment, observational evidence and modeling favor a
volcanic origin for many of them although other origins are not excluded.
2. Surface geochemistry
We examined various lander data acquired by the missions sent by USSR in order to understand
the basic geochemical processes governing the properties of Venusian surfaces.
Terrestrial hydrology, glaciaology, and volcanism
Mongolia and Siberia are territories of opportunity for geologists. I have been working on a variety of
research projects involving history of water. Many of these projects are related to planetary
studies since the investigated geological features or phenomenon served as terrestrial analogs. Fieldwork
in Mongolia and Siberia normally requires expedition.
For some more details on the expeditions, see this
link.
1. Paleolake study in Mongolia
Earth's climate and hydrosphere are strongly interconnected. When climate changes, it affects greatly the
water budget on the Earth surface. This process can be studied by investigating evidence, for example,
of paleolake landforms. We conducted fieldwork on paleolake shorelines in the Gobi-Altai.
The project is strongly tied with an archaeological inquiry on why ancient humans migrated and settled
in the region.
2. Subglacial volcanism in Tuva, Siberia
Quaternary glaciation in southern Siberia coincided with the timing of volcanism on the Azas Plateau in
the Tuva Republic. We conducted fieldwork in this remote region and studied ice-magma interactions.
3. Paleolakes and cataclysmic flooding along the upper Yenisei River, Mongolia and Siberia
Paleolakes were formed by a number of damming mechanisms along the upper Yenisei River drainages both in
Mongolia and Siberia during the Quaternary period. The best example is a large lake sustained in the
Darhad Basin in northern Mongolia by glacier blocking of the Little Yenisei River. Some of these lakes became unstable and
produced floods of immense scales. The evidence for such events includes gravel dunes widely distributed in the Kyzyl Basin within the Tuva Republic. We have conducted
preliminary studies on both the paleolakes and cataclysmic flooding.
4. Glaciation in Darhad Basin, northern Mongolia
We investigated the history of late Quaternary glaciation in the Darhad Basin, northern Mongolia. The work has
revealed a complex chronology and glaciar bahaviors.
5. Catastrophic flooding responsible for the creation of Channeled Scabland, USA
We conducted computer simulations of the flooding presumably responsible for the formation of the
Channeled Scabalnd in order to investigate its hydraulic conditions.
Possible terrestrial impact craters
1. Sirente crater field, central Italy
The Sirente crater field represents a possible rare example of small impact craters formed in
unconsolidated sediments. This is because small craters, particularly ones with morphology made of
"soft" materials, are difficult to survive in the highly active terrestrial erosional environment.
However, its impact origin has not been proven. This project is in progress.
2. Tsenkher structure, Black Gobi, Mongolia
The Tsenkher structure resides deep in the Gobi Desert. It is a 3.6-3.7 km wide circular and
isolated feature with a raised rim and prominent ejecta layers. It has been proposed to be an impact
crater but volcanic origin is not excluded. The research is in progress.
Geoarchaeology
1. Cave geology and archaeology in Mongolia
Caves are extensively distributed in Mongolia because of the presence of widespread limestone outcrops.
We are investigating their geology and also how ancient humans used them.
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