Magnetic Anomaly and Model of the Lonar Meteorite Impact Crater in Maharashtra, India

The ground magnetic field of the Lonar impact crater (Maharashtra State, India) and its surrounding area was measured and studied utilizing 2.5-dimensional potential field modelling. Field data showed the crater depression is associated with a strong circular negative anomaly with an amplitude of more than 1000 nT. The negative anomaly, however, decreases smoothly while moving from south to north. Most of the crater rim exhibits anomalous positive values. Negative anomalies at the rim are seen in the south–southwestern sections and coinciding in the northeastern section with the Dhar valley. Our study shows that most of the anomaly is caused by the topographic effect and a strong SE directed natural remanent magnetization of Deccan Trap basalts, which are the target of the Lonar-creating projectile. The magnetic anomaly of the relatively weakly magnetized impact-produced allochthonous breccia and post-impact sediments is small, being less than 150 nT.

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Raman spectroscopy of shocked gypsum from a meteorite impact crater

International Journal of Astrobiology ◽

10.1017/s1473550416000367 ◽

2016 ◽

Vol 16 (3) ◽

pp. 286-292 ◽

Cited By ~ 1

Author(s):

Connor Brolly ◽

John Parnell ◽

Stephen Bowden

Keyword(s):

Raman Spectroscopy ◽

Impact Crater ◽

Hydrothermal Systems ◽

Microbial Colonization ◽

Meteorite Impact ◽

Gale Crater ◽

Significant Statistical Difference ◽

Basement Rocks ◽

Hydrothermal Springs ◽

Post Impact

AbstractImpact craters and associated hydrothermal systems are regarded as sites within which life could originate on Earth, and on Mars. The Haughton impact crater, one of the most well preserved craters on Earth, is abundant in Ca-sulphates. Selenite, a transparent form of gypsum, has been colonized by viable cyanobacteria. Basement rocks, which have been shocked, are more abundant in endolithic organisms, when compared with un-shocked basement. We infer that selenitic and shocked gypsum are more suitable for microbial colonization and have enhanced habitability. This is analogous to many Martian craters, such as Gale Crater, which has sulphate deposits in a central layered mound, thought to be formed by post-impact hydrothermal springs. In preparation for the 2020 ExoMars mission, experiments were conducted to determine whether Raman spectroscopy can distinguish between gypsum with different degrees of habitability. Ca-sulphates were analysed using Raman spectroscopy and results show no significant statistical difference between gypsum that has experienced shock by meteorite impact and gypsum, which has been dissolved and re-precipitated as an evaporitic crust. Raman spectroscopy is able to distinguish between selenite and unaltered gypsum. This shows that Raman spectroscopy can identify more habitable forms of gypsum, and demonstrates the current capabilities of Raman spectroscopy for the interpretation of gypsum habitability.

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POST IMPACT RECOVERY OF THE DEEP GRANITIC BIOSPHERE OF THE CHICXULUB IMPACT CRATER

10.3997/2214-4609.202134192 ◽

2021 ◽

Author(s):

S.N. Quraish ◽

K. Grice ◽

C. Cockell ◽

A. Holman ◽

P. Hopper ◽

...

Keyword(s):

Impact Crater ◽

Chicxulub Impact Crater ◽

Post Impact ◽

Chicxulub Impact

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The Carancas meteorite impact crater, Peru: Geologic surveying and modeling of crater formation and atmospheric passage

Meteoritics and Planetary Science ◽

10.1111/j.1945-5100.2009.tb00783.x ◽

2009 ◽

Vol 44 (7) ◽

pp. 985-1000 ◽

Cited By ~ 49

Author(s):

T. KENKMANN ◽

N. A. ARTEMIEVA ◽

K. WÜNNEMANN ◽

M. H. POELCHAU ◽

D. ELBESHAUSEN ◽

...

Keyword(s):

Impact Crater ◽

Crater Formation ◽

Meteorite Impact

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The Whitecourt meteorite impact crater, Alberta, Canada

Meteoritics and Planetary Science ◽

10.1111/j.1945-5100.2010.01118.x ◽

2010 ◽

Vol 45 (9) ◽

pp. 1429-1445 ◽

Cited By ~ 20

Author(s):

Randolf S. KOFMAN ◽

Christopher D. K. HERD ◽

Duane G. FROESE

Keyword(s):

Impact Crater ◽

Meteorite Impact

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Umm al Binni Structure, Southern Iraq, as a Postulated Late Holocene Meteorite Impact Crater

Comet/Asteroid Impacts and Human Society ◽

10.1007/978-3-540-32711-0_4 ◽

2007 ◽

pp. 89-103 ◽

Cited By ~ 1

Author(s):

S. Master ◽

T. Woldai

Keyword(s):

Late Holocene ◽

Impact Crater ◽

Meteorite Impact ◽

Southern Iraq

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Survival of Extremotolerant Bacteria from the Mukundpura Meteorite Impact Crater

Astrobiology ◽

10.1089/ast.2018.1928 ◽

2019 ◽

Vol 19 (6) ◽

pp. 785-796 ◽

Cited By ~ 1

Author(s):

Rebecca S. Thombre ◽

E. Shivakarthik ◽

Bhalamurugan Sivaraman ◽

Parag A. Vaishampayan ◽

Arman Seuylemezian ◽

...

Keyword(s):

Impact Crater ◽

Meteorite Impact

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Probable Meteorite Impact Crater in Central Sweden

Nature Physical Science ◽

10.1038/physci229090a0 ◽

1971 ◽

Vol 229 (3) ◽

pp. 90-92 ◽

Cited By ~ 25

Author(s):

NILS-BERTIL SVENSSON

Keyword(s):

Impact Crater ◽

Meteorite Impact

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Analysis of the Czech magnetic anomaly data obtained by ground-based and airborne magnetic surveys

10.5194/egusphere-egu2020-3314 ◽

2020 ◽

Author(s):

Pavel Hejda ◽

Dana Čápová ◽

Eva Hudečková ◽

Vladimír Kolejka

Keyword(s):

Magnetic Anomaly ◽

Magnetic Anomalies ◽

Data File ◽

Ore Deposits ◽

Substantial Contribution ◽

Magnetic Survey ◽

Contour Maps ◽

Anomaly Map ◽

Ground Magnetic ◽

Airborne Survey

The modern epoch of ground magnetic surveying activity on the Czech territory was started by the Institute of Geophysics by setting up a fundamental network of the 1st order in 1957-58. It consists of 199 points and was reoccupied in 1976-78 and 1994-96. The anomaly maps were constructed by subtraction of the IGRF model.Extensive aeromagnetic measurements have been performed from 1959 to 1972 by permalloy probe of Soviet provenience. The accuracy of the instrumentation was about (and often above) 10 nT. The second period of airborne survey started in 1976. Thanks to the deployment of proton precession magnetometer, the accuracy improved to ~ 2 nT. Since 2004 the measurements were carried out by caesium magnetometer. The data were digitized, known anthropogenic anomalies were cleared away and data were transformed to the regular grid with step 250 m. The final data file of magnetic anomalies &#916;T, administered by the Czech Geological Survey, represents a substantial contribution to the exploration of ore deposits and to the structure geology in general.In view of the fact that data file of magnetic anomalies was compiled from data acquired by heterogeneous methods in the course of more than 50 years, our recent study is aimed at looking into the homogeneity of the data by comparison them with ground-based magnetic survey. A simple comparison of the contour maps showed good similarity of the large regional anomalies. For more detailed analysis, the variation of &#916;T in the neighbourhood of all points of the fundamental network was inspected and the basic statistic characteristics were computed. Summary results as well as several examples will be presented accordingly as the INSPIRE compliant services and eventually as the user-friendly web map application and made available on the CGS Portal http://mapy.geology.cz/ and on the updated web of the CzechGeo/EPOS consortium www.czechgeo.cz. Incorporating the map into the World Digital Magnetic Anomaly Map (WDMAM &#8211; IAGA) is also under consideration. This data will also be interesting for the EPOS.

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