¿Is the rubidium-strontium method of dating “rocks” really useful or really useless?
The gradualist mindset finds it extremely difficult to reconcile Ptolemy’s map of West Africa with the current incarnation of West Africa.
These academic issues coupled with the gradualist mindset make it extremely difficult / impossible [delete as appropriate] for mainstream researchers to reconcile Ptolemy’s map of West Africa with modern maps without making some astonishing alignments.
Malaga Bay – Fortunate Isles Revisited
Expansion and contraction artefacts on the surface of the Earth can be identified.
Malaga Bay – Alaskan Muck: The Swing State
The bathymetry of the Arctic Ocean provides very clear evidence that the Earth’s Crust cracked open as the Earth inflated beneath the surface landmasses.
The Afar Triple Junction suggests the Earth’s inflationary history involves periods of cooling and contraction and subsequent phases of heating and inflation.
Malaga Bay – Alaskan Muck: Anaximander’s Cake
Malaga Bay – The Arabian Horizon – The Lost Lands: Punt
A triple junction is the point where the boundaries of three tectonic plates meet.
Wikipedia – Triple junction
Senegal Triple Junction
Comparing Ptolemy’s map of West Africa with the current incarnation of West Africa indicates the Senegal Triple Junction fractured in the Current Era.
The Senegal Triple Junction fracture was inflationary with rips and tears.
Casamance is the area of Senegal south of the Gambia including the Casamance River.
Wikipedia – Casamance
Conakry is the capital and largest city of Guinea.
Wikipedia – Conakry
Los Archipelago Ring Structure
The Senegal Triple Junction is also associated with volcanic activity.
Los Islands (Islas de los Idolos), a group of islands off the coast of French Guinea, West Africa, lying south of Sangarea Bay, between 9° 25′ and 9° 31′ N. and 13° 46′ and 13° 51′ W., and about 80 m. N.N.W. of Freetown, Sierra Leone. There are five principal islands: Tamara, Factory, Crawford, White (or Ruma) and Coral.
The two largest islands are Tamara and Factory, Tamara, some 8 m. long by 1 to 2 m. broad, being the largest.
The archipelago is of volcanic formation, Tamara and Factory islands forming part of a ruined crater, with Crawford Island as the cone.
The highest point is a knoll, some 450 ft. above sea-level, in Tamara.
1911 Encyclopædia Britannica – Volume 17 – Los Islands
Towards the south-west the heights are continued through the long peninsula of Konakri and the island of Tumbo, which project westward in the direction of the Los archipelago.
These “Islas de los Idolos,” or “Islands of the Idols,” are so called from the sacred images here found by the early navigators.
They are certainly of volcanic origin, the two principal members of the group exceeding 600 feet in height and disposed in the form of a vast and ruined crater encircling a central cone-shaped islet.
The prevailing formations are blue and yellowish lavas surrounding large masses of porphyry.
Africa – Volume III – West Africa
Elisée Reclus – Edited by Augustus Henry Keane – 1892
If the Los Archipelago Ring Structure dating is correct then Ptolemy lived 104.3 ± 1.7 million years ago.
The Los Archipelago ring structure (Guinea, West Africa) is composed of peralkaline nepheline syenite, which crops out over two long crescent-shaped islands (Tamara, Kassa), five islets and a central island (Roume).
A Rb-Sr whole-rock isochron gives an age of 104.3 ± 1.7 (2σ) Ma (MSWD = 1.28).
The initial Sr isotopic composition (87Sr/86Sr0 = 0.7040) is compatible with a mantle origin with minor or no crustal influence.
The geological environment and the emplacement age of the Los Archipelago point to formation during the continental breakup between the West Africa and South America and early rifting of the Equatorial Atlantic Ocean.
The Los Archipelago Nepheline Syenite Ring Structure:
A Magmatic Marker of the Evolution of the Central and Equatorial Atlantic
Christian Moreau, Daniel Ohnenstetter, Daniel Demaiffe, Bernard Robineau
The Canadian Mineralogist 34(2):281-299 – April 1996
The Rubidium-Strontium dating method is a radiometric dating technique used by scientists to determine the age of rocks and minerals from the quantities they contain of specific isotopes of rubidium (87Rb) and strontium (87Sr, 86Sr).
Development of this process was aided by German chemists Otto Hahn and Fritz Strassmann, who later went on to discover nuclear fission in December 1938.
The utility of the rubidium–strontium isotope system results from the fact that 87Rb (one of two naturally occurring isotopes of rubidium) decays to 87Sr with a half-life of 49.23 billion years.
Wikipedia – Rubidium–Strontium Dating
On the other hand:
The Rubidium-Strontium dating might be in error by 104.3 ± 1.7 million years.
Review the evidence and draw your own conclusions.