David Rajmon

GeoSophix

http://www.geoexpro.com/articles/2016/01/an-overlooked-petroleum-system In petroleum exploration, the concept of hydrocarbon generation on the continental crust is completely accepted. However, modelling exercises demonstrate that, if the source rock is present and a sufficient amount of sediment is deposited, it is possible to generate hydrocarbo...

Accurate prediction of sediment porosity is important in multiple E&P applications including thermal history, reservoir quality, and pore pressure prediction. In quartzose sandstones with low thermal maturities, porosity evolution during burial is controlled primarily by effective stress (compaction). Many workflows assume that the effective stress...

Circular polygonal feature 4.5 km in diameter near Urengoy in West Siberia is unique in the wider area. Geologic review indicates that a meteorite impact or transpression tectonics are the most likely formation mechanisms.

Suspected Earth Impact Sites database contains over 600 proposed impact structures with rigorous referencing but many poorly documented. We used remote sensing data from the Internet to investigate the nature of some of the structures and we rejected impa

Spherules from ODP 709c (Indian ocean) diplay petrographic and geochemical characteristics similar to spherules from ODP 216 and 292 (SE Asia). The data, however, neither strongly support nor reject the hypothesis of a third Upper Eocene ejecta layer in SE Asia.

Suspected Earth Impact Sites is a new database aspiring to provide reliable basic data and references on proposed but not confirmed impact structures.

— The rocks exposed in the rim of the 2.5-km-wide and 3.7-Ma-old Roter Kamm crater in southwest Namibia are cut by breccia veins that macroscopically resemble, and were originally described as, pseudotachylytes. The veins were later shown to be cataclasites with no evidence for melting. 40Ar/39Ar data for vein and host rock samples indicate a low-g...

Abstract— Maria Tranquillitatis and Fecunditatis have been mapped based on Clementine image mosaics and derived iron and titanium maps. Impact craters served as stratigraphic probes enabling better delineation of compositionally different basaltic units, determining the distribution of subsurface basalts, and providing estimates of total basalt thi...

Maria Tranquillitatis and Fecunditatis have been mapped based on Clementine image mosaics and derived iron and titanium maps. Impact craters served as stratigraphic probes enabling better delineation of compositionally different basaltic units, determining the distribution of subsurface basalts, and providing estimates of total basalt thickness and...

The target rocks from Roter Kamm crater retained NRM components related to the Kalahari APWP for ~1.1 0.9, ~0.7 0.6 and ~0.5 Ga. There is no evidence for re-magnetization of the Roter Kamm samples at ~300 Ma or during the impact at 3.7 Ma.

Mosaics of Clementine images and FeO and TiO_2 were used to map different basalt units in M. Tranquillitatis. 4 to 5 units with different TiO_2 content were identified.

The rim rocks of the 2.5 km Roter Kamm crater in southwest Namibia are cut by breccia veins that macroscopically resemble pseudotachylytes. 40Ar/39Ar data, coupled to other published data, show that these veins never approached melting temperatures and only attained temperatures of 250-330 °C.

Current structure count Confirmed (Earth Impact Database): 174 (although I include Arkenu 1 and 2 in my class 3) Confirmed (SEIS): 4 Probable: 115 Possible: 449 Improbable 20 Rejected: 73 Purpose The aim for this database is to: -Provide ever-evolving list helping to steer research on suspected impact structures. -Provide basic data for each struct...