MOUNTAIN BUILDING AND EVOLUTION OF PEAK JAYA, OCEANIA
-
摘要: 位于大洋洲新几内亚岛的查亚峰的形成与中新世以来澳大利亚大陆北部被动边缘俯冲碰撞到Melanesian岛弧之下有关.2.8 Ma以来, 查亚峰岩石隆升幅度为7 000 m, 隆升速率为2.5 mm/a, 其剥蚀速率为0.7 mm/a.据查亚峰南坡石炭—二叠系测年得出, 自2.3 Ma以来, 岩石隆升幅度为6 500 m, 隆升速度为2.88 mm/a, 剥蚀速率为1.7 mm/a; 更南可能为前寒武纪的绿片岩分布区, 剥蚀速率更快, 已剥蚀深度达9 km, 是全岛剥露最深的地区.正是这种强烈的切割和剥蚀, 在均衡抬升作用强烈影响下使查亚峰成为大洋洲最高峰.Abstract: The Peak Jaya and its neighboring areas within the New Guinea island in Oceania are located at the junction of several lithospheric plates: Pacific plate, Australian plate and Southeast Asian plate. In the Peak Jaya are present a concentration of tectonic stress, an intensification of tectonic disturbance and a complicate tectonic evolution history. The mountain building of Peak Jaya is a product of subduction of north Australian passive continental margin into the area below the Melanesian island arc since the Miocene. Since 2.8 Ma, the rock uplift amplitude of the Peak Jaya has reached about 7 000 m with the uplift rate 2.5 mm/a and the exhumation rate 0.7 mm/a.Based on the dating of the Carboniferous-Permian obtained in the southern slope of Peak Jaya, the rock uplift amplitude has reached, since 2.3 Ma, 6 500 m with the uplift rate 2.8 mm/a and exhumation rate 1.7 mm/a. Further to the south, there exists a greenschist domain of probably Precambrian. The exhumation rate there has reached a faster rate, since the exhumed depth has already reached 9 km, the deepest part of the whole island. It is this violent down-cutting and exhumation that has made Peak Jaya the highest peak in Oceania by means of equilibrium elevation.
-
Key words:
- uplift /
- exhumation /
- Peak Jaya /
- Oceania
-
(1)北海岸盆地区, 它们由第三纪的火山岩和沉积岩组成, 上面叠加有上新世—更新世的盆地层序; (2)由蛇绿岩及高级变质岩所组成的混杂岩, 即太平洋板块与澳大利亚板块汇聚的缝合带; (3)具有多期变形的Derewo变质岩带; (4)一条在中生代—老第三纪沉积层中的复杂逆冲断裂带; (5)一个40~50 km宽、轴面北倾的复向斜, 它是由中生代—新生代冒地槽沉积层所组成, 其核部为新第三纪灰岩; (6)一条由古生代地层组成的向南倒转的复背斜; (7)前陆冲断层域, 其中既有中生代—新生代冒地槽沉积层, 又有变形的新第三纪前陆磨拉石沉积层序
Fig. 1. Tectonic of New Guinea
图 2 查亚峰及邻区地质图(据文献[6]简化)
1.第四纪冲积层; 2.上新世侵入体; 3.新第三纪Ainod地层; 4.老第三纪Faumai地层; 5.白垩纪Kembelangan地层; 6.矽卡岩矿床; 7.背斜轴; 8.向斜轴; 9.逆断层; 10.断层
Fig. 2. Geological map of Peak Jaya and its adjacent area
-
[1] Giddings J W, Sunata W, Pigram C. Reinterpretation of palaeomagnetic result from the Bird's Head, Irina Jaya: new constraints on the drift history of the Kemum terrane[J]. Exploration Geophysics, 1993, 24: 283-290. doi: 10.1071/EG993283 [2] Puntodewo S S O, McCaffrey R, Calais E, et al. GPS measurements of crustal deformation within the Pacific-Australia plate boundary zone in Irian Jaya, Indonesia[J]. Tectonophysics, 1994, 237: 141-153. doi: 10.1016/0040-1951(94)90251-8 [3] McDowell F W, McMahon T P, Warren P Q, et al. Pliocene Cu-Au-bearing igneous intrusions of the Gunung Bijih (Ertsberg) district, Irian Jaya, Indonesia: K-Ar geochronology[J]. The Journal of Geology, 1996, 104: 327-340. doi: 10.1086/629828 [4] Weiland R J, Cloos M. Pliocene-Pleistocene asymmetric unroofing of the Irian fold belt, Irian Jaya, Indonesia: apatite fission-track thermochronology[J]. Geology Society of America Bulletin, 1996, 108 (11): 1438-1449. doi: 10.1130/0016-7606(1996)108<1438:PPAUOT>2.3.CO;2 [5] Nash C R, Artmont G, Gillan M L, et al. Structure of the Irian Jaya mobile belt, Irian Jaya, Indonesia[J]. Tectonics, 1993, 12 (2): 519-535. doi: 10.1029/92TC02360 [6] Mertig H J, Rubin J N, Kyle R. Sharn Cu-Au orebodies of the Gunung Bijih (Ertsberg) district, Irian Jaya, Indonesia[J]. Journal of Geochemical Exploration, 1994, 50: 179-202. doi: 10.1016/0375-6742(94)90024-8 [7] George D, MacDonald L, Clark Arnold. Geological and geochemical zoning of the Grasberg igneous complex, Irian Jaya, Indonesia[J]. Journal of Geochemical Exploration, 1994, 50: 143-178. doi: 10.1016/0375-6742(94)90023-X [8] Housh T, James E, McMahon T. Isotopic constraints "post-orogenic" magmatism in the central ranges of Irian Jaya, Indonesia[J]. American Geophysical Union, 1994, 75(Suppl): 739. [9] Abbott L D, Silver E A, Anderson R S, et al. Measurement of tectonics surface uplift rate in a young mountain belt[J]. Nature, 1997, 385 (6616): 501-507. doi: 10.1038/385501a0 [10] Abers G A. Shallow dips of normal faults during rapid extension: earthquakes in the Woodlark-D'Entrecasteaux rift system, Papua New Guinea[J]. Journal of Geophysical Research, 1997, 102: 15301-15317. doi: 10.1029/97JB00787 [11] Baldwin S L, Lister G S, Hill E J, et al. Thermochronogic constraints on the tectonic evolution of active metamorphic core complexes, D'Entrecasteaux Islands. Papua New Guinea[J]. Tectonics, 1993, 12: 611-628. doi: 10.1029/93TC00235 [12] Molnar P, England P. Late Cenozoic uplift of mountain ranges and global climate change: chicken or egg?[J]. Nature, 1990, 346: 29-34. doi: 10.1038/346029a0 -
下载:
点击查看大图
图(3)
计量
- 文章访问数: 4073
- HTML全文浏览量: 485
- PDF下载量: 12
- 被引次数: 0
