404
G. ¸
Serban et al.
From west to east, at the contact with the Igni¸ s Massif, appear in a reduced form clays,
marls and sands, followed by andesites with biotite in the Rooster Crest and basaltoide
andesites and andesites in the Gutâi Peak. On the northern outskirts starting from the
Mara River valley, the petrography is defined by a series of micaceous sandstones
and marly-clays (flysch) completed with consistent colluvial and deluvial-coluviale
deposits. Same distribution is found on the Maramures , ului Piedmont, where the
mentioned deposits are pierced by Tortonian age formations like marl, limestone,
tuffs, gypsum and salt, completed with sands, sandstones and conglomerates.
The huge and massive volcanic plateau of Ignis , Massif is composed of basaltoide
andesites, which have been exploited in the Limpedea quarry and can also be found
also found in Piatra Range. To the southeast, of volcanic plateau, on the left slope
of the Runcu Valley, appear sporadically andesites with biotite and andesites with
amphiboles.
The whole northern (from Piatra Creek) and eastern (up to the Mara River) periphery of the Igni¸ s Massif is organized on the same colluvial and deluvial-colluvial with
blocks deposits, continued with a sedimentary structure which consist of limestone,
sands, sandstones and conglomerates and one of Tortonian age deposits of marl,
limestone, tuffs, gypsum and salt to the periphery. The deluvial-colluvial deposits
are pierced in the central part by a few “witnesses” of the same magmatic origin, like
of Ignis , Massif.
In the western half, the Romanian Upper Tisa Basin is maintaining its petrographic
complexity. Thus, basaltoide andesites of Ignis , Massif are continued to the periphery
with the quartz andesites and coarse pyroclastic deposits, and at the contact with the
Oas , ului Depression with marly clays and sands.
Beyond this depression, organized by a rich fluvial network into a genuine water
gathering market, developed on sands, gravel and red clay deposits in the interfluves
and sands and gravel on valleys (with limited quantity reserves of underground water),
resurface volcanic structures, with insular aspect.
Thus, basaltoide andesites, frequently associated with coarse pyroclastic rocks,
appear on considerable surfaces, even if not in the form of a compact plateau, like
Ignis , Massif. They are found in the two ramifications of the Oas , Mountains to the
south of the Talna Valley, to the south and the north-west of C˘ aline¸ sti-Oa¸ s water
reservoir, continuing north up to the border with Ukraine, and to the north of Rea
Valley, on Piatra Vâscului Ridge.
Secondary, andesites with biotite appear in the southern part of the Talna Valley,
the rhyolites to the north of the confluence of the Talna Valley with Tur River and
porphyric granodiorites in the lobe of the Lechincioara Valley and Tur River and to
the east of the same Lechincioara Valley.
The quartz andesites can be observed in the two peaks located in the north-western
extremity of the Tur Basin and very frequently andesites with pyroxene intercalated
with basaltoide andesites in the whole sector situated between Lechincioara Valley
of the Tur River and northern border.
The periphery of the volcanic apparatus related to Oas , Mountains is characterized
by the presence of marly clays and sands or by the presence of sands, gravel and red
clays on the western outskirts of them.
G. ¸
Serban et al.
From west to east, at the contact with the Igni¸ s Massif, appear in a reduced form clays,
marls and sands, followed by andesites with biotite in the Rooster Crest and basaltoide
andesites and andesites in the Gutâi Peak. On the northern outskirts starting from the
Mara River valley, the petrography is defined by a series of micaceous sandstones
and marly-clays (flysch) completed with consistent colluvial and deluvial-coluviale
deposits. Same distribution is found on the Maramures , ului Piedmont, where the
mentioned deposits are pierced by Tortonian age formations like marl, limestone,
tuffs, gypsum and salt, completed with sands, sandstones and conglomerates.
The huge and massive volcanic plateau of Ignis , Massif is composed of basaltoide
andesites, which have been exploited in the Limpedea quarry and can also be found
also found in Piatra Range. To the southeast, of volcanic plateau, on the left slope
of the Runcu Valley, appear sporadically andesites with biotite and andesites with
amphiboles.
The whole northern (from Piatra Creek) and eastern (up to the Mara River) periphery of the Igni¸ s Massif is organized on the same colluvial and deluvial-colluvial with
blocks deposits, continued with a sedimentary structure which consist of limestone,
sands, sandstones and conglomerates and one of Tortonian age deposits of marl,
limestone, tuffs, gypsum and salt to the periphery. The deluvial-colluvial deposits
are pierced in the central part by a few “witnesses” of the same magmatic origin, like
of Ignis , Massif.
In the western half, the Romanian Upper Tisa Basin is maintaining its petrographic
complexity. Thus, basaltoide andesites of Ignis , Massif are continued to the periphery
with the quartz andesites and coarse pyroclastic deposits, and at the contact with the
Oas , ului Depression with marly clays and sands.
Beyond this depression, organized by a rich fluvial network into a genuine water
gathering market, developed on sands, gravel and red clay deposits in the interfluves
and sands and gravel on valleys (with limited quantity reserves of underground water),
resurface volcanic structures, with insular aspect.
Thus, basaltoide andesites, frequently associated with coarse pyroclastic rocks,
appear on considerable surfaces, even if not in the form of a compact plateau, like
Ignis , Massif. They are found in the two ramifications of the Oas , Mountains to the
south of the Talna Valley, to the south and the north-west of C˘ aline¸ sti-Oa¸ s water
reservoir, continuing north up to the border with Ukraine, and to the north of Rea
Valley, on Piatra Vâscului Ridge.
Secondary, andesites with biotite appear in the southern part of the Talna Valley,
the rhyolites to the north of the confluence of the Talna Valley with Tur River and
porphyric granodiorites in the lobe of the Lechincioara Valley and Tur River and to
the east of the same Lechincioara Valley.
The quartz andesites can be observed in the two peaks located in the north-western
extremity of the Tur Basin and very frequently andesites with pyroxene intercalated
with basaltoide andesites in the whole sector situated between Lechincioara Valley
of the Tur River and northern border.
The periphery of the volcanic apparatus related to Oas , Mountains is characterized
by the presence of marly clays and sands or by the presence of sands, gravel and red
clays on the western outskirts of them.