Stefan Airinei
Abstract
The author presents a synthesis of the magnetic surveys carried out in the
Sub-Carpathians of Eastern Muntenia during the period 1952 to 1957, and resulting
in maps for the 
Z
component, the Z
anomaly, the ZR
regional anomaly and the ZL local anomaly.
The Za magnetic anomaly was obtained using the correction for ZA component
by the normal geomagnetic field ZN. The average, percent values both for the
normal field and the magnetic anomaly, estimated for 84 points uniformly distributed
in the surveyed area, are the following: ZN = 99.54% and Za = 0.46%.
The Za
anomaly consists of two series terms: regional (Zr
+ Zr'
+ … with
an average, percent value 0.45%) and local (Zl +
Zl' + …,
with an average, per cent value 0.02%). The regional terms correspond to the
effect both of
the metamorphic complex of the basement (Zr)
and the magnetic intrusive bodies (Zr').
The first term of near 100
,
represents the prolongation of the basement of the Dobrudgea compartment: Constanta – Cernavoda – Tîndarei,
while the second term, with values up to 140, corresponds
to the eruptive masses similar to those generating the anomalies of Palazu
Mare, Tîndarei,
Cilibia. The local terms correspond partly to the effects of the covering geological
formations and partly to the effects of geological formations located at immediately
underlying tectonical levels.
The terms of the Za,
magnetic anomaly may be conjugated with similar terms of the gravity anomaly.
The ZR regional
magnetic anomaly of positive sign is superimposed on the gR regional
gravity anomaly of negative sign. The ZL local
magnetic anomalies correspond to gL local gravity anomalies forming,
according to the sign of the anomalies, four types of couples.
The geological significance of each term of the Z anomaly gives a complex
image of the tectonics which consists, at least, of three structures: 1) structure
of surface deposits, 2) structure of directly underlying deposits, 3) structure
of the basement.