ABSTRACTS / RESUMES - Comitato Glaciologico Italiano

HUNAN ZHANG & WEIGUANG CHEN
Features of tectonic landform of fault blocks
in South China coastal area
Seismological Bureau of Guangdong Province,
Guangzhou 510070, China
In this paper, the south China coastal area is divided into
several fault block areas (first class), sub-areas (second
class) and mini-areas (third class) based on their dynamic
signs, heridity, uniformity, particularity and the mode of
action of tectonic stress. Their tectonic geomorphological
features are elaborated and the amplitude as well as the rate
of relative motion since the end of the late Pleistocene
epoch are estimated from 14C data of the samples which
fundamentally represent the sea level in different periods.
It is found that the value of amplitude and rate of fault
block movement, tend to become smaller from the east
and west towards the middle. This feature could he related
to the «screen» effect of the Taiwan-Penghu-Quanzhou­
Shantou strong earthquake area and the Leizhou-Qiongya
earthquake area.
WEIQIANG ZHANG, ZHENGUO HUANG, RUIRU HE
& ZHENGCHONG HE
Laterite evolution, climate change and tectonic motion
in China
Guangzhou Institute of Geography, CAS, 100 Xian Lie Road,
510070 Guangzhou, China
From the studying of 189 profiles of red earth in China,
there is a couping relationship between the red earth evolution,
paleoclimate change and tectonic motion. Three
main cycles of tectonic-climate (red earth) can be deduced
since Quaternary, and each cycle can subdivided into two
stage. The former is characterized by relatively structural
stillstand and warm climate (interglacial stage), the latter,
tectonically active preiod and cold warm (glacial stage) .
The red earth periods are corresponded with the warm climate
and relatively structural stillstand.
BIQIANG ZHAO 1 & WEIQIANG ZHANG 2
Plate tectonics and Quaternary volcanicity in China
1 Guangzhou Branch, Chinese Academy of Sciences, 100 Xian Lie Road,
510070 Guangzhou, China
2 Guangzhou Institue of Geography, CAS, 100-1 Xian Lie Road,
510070 Guangzhou, China
There are 10 groups of Quaternary volcanoes in China.
From the relationship between volcanicity and plate tectonics,
the groups of volcanoes can be into the follwing seven
types, as follows:
1. Volcanicity of ocean bottom and oceanic island of inside
plate in South China Sea basin.
2. Volcanicity of rift valley of plate margin in Leizhou Peninsula
and Northern Hainan Island.
3. Volcanicity of Taiwan Island arc which is a consuming
zone of plates.
4. Volcanicity of rift valley of plate margin in the bay of
Bohai Sea.
5. Volcanicity of rift valley of inside plate along the Da
Hinggan Mountain and Datong fault trough .
6. Volcanicity of plate margin along the Xiao Hinggan
Mountain and Changbai Mountain which are affected by
subduction of plates.
7. Volcanicity of inside plate in Tengchong and northern
margin of Tibet Plateau which is affected by collision of
plates.
According to incomplete statistics (collected 231 dating
data of volcanic rocks up-to-date) dating data during Qi,
Q2, Q3 and Q4 make up 37.2, 46.8,12.6 and 4.0 per cent,
respectively, which show the change of volcanicity during
Quaternary in varying degrees: the most strong period of
volcanicity is in Q2, the secondary is in Qi, and the most
weak period of thatis in Q3 and Q4.
From the study of the important events of plate movement
in China or East Asia i.e. in Eastern China (Taiwan Island)
the collision between Philippine Sea plate and Eurasian
plate occurred in the Himalayan movement between Pliocene
and Pleistocene, in Southern China the second spreading
of South China Sea and the Shikoku basin north of
Philippine Sea plate spreaded in 32 -17 and 30 -15 My
BP (from Holocene to Miocene) respectively and in Western
China the accelerating uplift of Tibet Plateau was
since Pleistocene, which was caused by the collision
between India plate and Eurasian plate, the distribution of
Quaternary volcanicity in China can be epitomized into
one basin, three rift valleys and three volcanic arcs.
The modern volcanicity occurred only in Taiwan Island,
the Xiao Hinggan Mountain and Changbai Mountains of
North-east China.
XITAO ZHAO
Development of the coral reefs and the tombolo of
Luhuitou Peninsula, Sanya City, Hainan Province
Institute of Geology, Chinese Academy of Sciences
Luhuitou Peninsula situated at the southern end of Hainan
Island is one of the areas where the Holocene fringing
reefs are the most developed in China. It consists of three
parts: the Luhuitouling tombolo island, the Yezhuang
tombolo and the Nanbianling-Huoling hills.
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