Angular Unconformity. “No Vestige of a Beginning”: The Immensity of Geologic Time

2018 ◽  
pp. 35-46
Keyword(s):  
Angular Unconformity ◽  
Geologic Time

LEONARDO DA VINCI’S AND NICOLAUS STENO’S GEOLOGY

2021 ◽  
Vol 40 (2) ◽  
pp. 293-331
Author(s):  
GIAN BATTISTA VAI
Keyword(s):  
Comparative Evaluation ◽  
Geological History ◽  
Basic Principles ◽  
Founding Fathers ◽  
Angular Unconformity ◽  
Geologic Time ◽  
The Earth ◽  
Relative Chronology ◽  
History Of ◽  
Do So

Anniversaries for the two founding fathers of geology occurring in the same year prompted a comparative evaluation of how the two contributed to establishing the basic principles of the discipline. To do so, passages from their publications, codices and manuscripts have been quoted directly. The Stenonian principles (‘original horizontality’, ‘original continuity’, and ‘superposition of individual strata’) are present in Leonardo’s notebooks amazingly formulated, using similar wording when studying the same area more than 150 years earlier. Also, Stenonian priority in naming and explaining geological concepts and processes (e.g., faulting, folding, angular unconformity, relative chronology) are mirrored in Leonardo’s writings and pictorial works. While Steno enjoys priority in stepwise restoration of the geological history of a given region, Leonardo was the first to construct a 3D geological profile representation and geomorphologic maps. Lastly, the paper focuses on diverging stances of the two savants about the Noachian Deluge and the age of the Earth. Already 500 years ago, Leonardo had solved the question of marine fossil remains of organic origin found in the mountains implying the possibility of deep geologic time in a statement of ‘eternalism’. 350 years ago, Steno solved the same question in a different way in which he retained a basic role for the Deluge and assumed a short age for the Earth by focusing mainly on short-lived sedimentary and geomorphologic processes.

The Geologic Time Spiral - A Path to the Past

10.3133/gip58 ◽  
2008 ◽  
Author(s):  
Joseph Graham ◽  
William Newman ◽  
John Stacy
Keyword(s):  
Geologic Time ◽  
The Past

Heterogeneous Data Searching Based on Geologic Time Ontology

2010 ◽  
Vol 12 (2) ◽  
pp. 194-199 ◽  
Author(s):  
Shaochun DONG ◽  
Hongwei YIN ◽  
Gang XU
Keyword(s):  
Heterogeneous Data ◽  
Geologic Time

RECONSTRUCTED ANCESTRAL ENZYMES SUGGEST THAT EARTH'S PHOTIC-ZONE TEMPERATURE MARKEDLY DECREASED OVER GEOLOGIC TIME

2016 ◽  
Author(s):  
Amanda Garcia ◽  
◽  
J. William Schopf ◽  
Shin-ichi Yokobori ◽  
Satoshi Akanuma ◽  
...  
Keyword(s):  
Photic Zone ◽  
Geologic Time ◽  
Zone Temperature

QUANTIFYING AND VISUALIZING EARTH’S MINERAL CHEMISTRY THROUGH GEOLOGIC TIME

2016 ◽  
Author(s):  
Daniel R. Hummer ◽  
◽  
Robert M. Hazen ◽  
Xiaogang Ma ◽  
Joshua J. Golden ◽  
...  
Keyword(s):  
Mineral Chemistry ◽  
Geologic Time

TRACKING TRACES OF PREDATION AND PARASITISM ON FOSSIL ECHINOIDS THROUGH GEOLOGIC TIME

2018 ◽  
Author(s):  
Lyndsey Farrar ◽  
◽  
Erin Graves ◽  
Elizabeth Petsios ◽  
Roger W. Portell ◽  
...  
Keyword(s):  
Geologic Time

scholarly journals Marine ammonia-oxidising archaea and bacteria occupy distinct iron and copper niches

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Roxana T. Shafiee ◽  
Poppy J. Diver ◽  
Joseph T. Snow ◽  
Qiong Zhang ◽  
Rosalind E. M. Rickaby
Keyword(s):  
Comparative Genomics ◽  
Trace Metals ◽  
Trace Metal ◽  
Ammonia Oxidation ◽  
Testable Hypothesis ◽  
Niche Separation ◽  
Toxicity Threshold ◽  
Geologic Time ◽  
Additional Explanation ◽  
Ammonia Oxidising Archaea

AbstractAmmonia oxidation by archaea and bacteria (AOA and AOB), is the first step of nitrification in the oceans. As AOA have an ammonium affinity 200-fold higher than AOB isolates, the chemical niche allowing AOB to persist in the oligotrophic ocean remains unclear. Here we show that marine isolates, Nitrosopumilus maritimus strain SCM1 (AOA) and Nitrosococcus oceani strain C-107 (AOB) have contrasting physiologies in response to the trace metals iron (Fe) and copper (Cu), holding potential implications for their niche separation in the oceans. A greater affinity for unchelated Fe may allow AOB to inhabit shallower, euphotic waters where ammonium supply is high, but competition for Fe is rife. In contrast to AOB, AOA isolates have a greater affinity and toxicity threshold for unchelated Cu providing additional explanation to the greater success of AOA in the marine environment where Cu availability can be highly variable. Using comparative genomics, we predict that the proteomic and metal transport basis giving rise to contrasting physiologies in isolates is widespread across phylogenetically diverse marine AOA and AOB that are not yet available in pure culture. Our results develop the testable hypothesis that ammonia oxidation may be limited by Cu in large tracts of the open ocean and suggest a relatively earlier emergence of AOB than AOA when considered in the context of evolving trace metal availabilities over geologic time.

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