DOI Page / Citation link:
https://doi.org/10.11588/diglit.748#0216
INVESTIGA TIONS A T ASSOS, 1881. 173
Occasionally, where this trachyte is in contact with older rocks,
instead of separating into large blocks, as is usually the case, it
breaks into many small angular fragments, and appears like a mass
of breccia. Several small areas of this formation are very decep-
tive, on account of the fact that where considerable decomposition
has taken place along the many small fractures, the rock closely
resembles a conglomerate with subangular pebbles.
Although this trachyte is for the most part considerably altered,
it generally preserves its appearance of durability. In rare in-
stances, however, it is altered almost to a white micaceous clay, and
at other times disintegrates, forming a grayish micaceous sand.
The relation of the second trachyte to the first is made evident
by a number of facts. It contains distinct fragments of the first
trachyte, which must have been picked up by the second at the time
of its eruption. These pieces are not numerous, but yet they are of
such a character as to leave no doubt concerning their identity and
signification. Small portions of other rocks are quite frequently
enveloped by the second trachyte, especially near its junction with
older formations, and some of these fragments are very inter-
esting.
It is evident that by the erosion of the second trachyte a consid-
erable portion of the first trachyte has been brought to the surface.
Southwest of the Acropolis is a narrow band of the first trachyte
extending northwest across the hill, and separating the two large
areas of the second trachyte. This belt lies upon a steep slope
directly beneath the high cliffs of the Acropolis, and there is abun-
dant reason in the structure and topographical relations for believ-
ing that the trachyte of the Acropolis was once connected with that
of the large area to the westward.
Beneath the cliffs of second trachyte, a short distance southwest
of the Acropolis, a long tongue of the first trachyte extends far to
the northwest, and there can be no doubt that this area also has
been exposed by the wearing away of the overlying formation.
That the second trachyte is of more recent eruption than the first
is made evident, also, by their relation to the volcanic conglomerate.
At the western base of the Acropolis, the trachyte of which it is com-
posed rests directly upon the ashes associated with the volcanic con-
glomerate. Near the port the small mass of second trachyte plainly
Occasionally, where this trachyte is in contact with older rocks,
instead of separating into large blocks, as is usually the case, it
breaks into many small angular fragments, and appears like a mass
of breccia. Several small areas of this formation are very decep-
tive, on account of the fact that where considerable decomposition
has taken place along the many small fractures, the rock closely
resembles a conglomerate with subangular pebbles.
Although this trachyte is for the most part considerably altered,
it generally preserves its appearance of durability. In rare in-
stances, however, it is altered almost to a white micaceous clay, and
at other times disintegrates, forming a grayish micaceous sand.
The relation of the second trachyte to the first is made evident
by a number of facts. It contains distinct fragments of the first
trachyte, which must have been picked up by the second at the time
of its eruption. These pieces are not numerous, but yet they are of
such a character as to leave no doubt concerning their identity and
signification. Small portions of other rocks are quite frequently
enveloped by the second trachyte, especially near its junction with
older formations, and some of these fragments are very inter-
esting.
It is evident that by the erosion of the second trachyte a consid-
erable portion of the first trachyte has been brought to the surface.
Southwest of the Acropolis is a narrow band of the first trachyte
extending northwest across the hill, and separating the two large
areas of the second trachyte. This belt lies upon a steep slope
directly beneath the high cliffs of the Acropolis, and there is abun-
dant reason in the structure and topographical relations for believ-
ing that the trachyte of the Acropolis was once connected with that
of the large area to the westward.
Beneath the cliffs of second trachyte, a short distance southwest
of the Acropolis, a long tongue of the first trachyte extends far to
the northwest, and there can be no doubt that this area also has
been exposed by the wearing away of the overlying formation.
That the second trachyte is of more recent eruption than the first
is made evident, also, by their relation to the volcanic conglomerate.
At the western base of the Acropolis, the trachyte of which it is com-
posed rests directly upon the ashes associated with the volcanic con-
glomerate. Near the port the small mass of second trachyte plainly