Rheomorphic ignimbrites of the Rogerson Formation, central Snake River plain, USA: record of mid-Miocene rhyolitic explosive eruptions and associated crustal subsidence along the Yellowstone hotspot track
Rheomorphic ignimbrites of the Rogerson Formation, central Snake River plain, USA: record of mid-Miocene rhyolitic explosive eruptions and associated crustal subsidence along the Yellowstone hotspot track
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美国斯内克河平原中部罗杰森组的流变熔结岩：中新世中期流纹岩爆发性喷发和沿黄石热点轨道相关的地壳沉降的记录
DOI：
10.1007/s00445-016-1003-x
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发表时间：
2016
影响因子：
3.5
通讯作者：
Knott T
中科院分区：
文献类型：
--
作者：
Knott T
美国罗杰森地堑位于黄石热点轨道和西斯内克河裂谷南部投影之间的交叉点。重新定义的11个流纹岩成员，≥ 420米厚，Rogerson组记录了大量的高温爆炸喷发，侵位广泛的火山灰和流变熔结凝灰岩片。然而，每一个成员都有微妙的不同的领域，化学和古地磁特征。新的区域对比表明，Brown's View熔结凝灰岩覆盖面积≥ 3300 km~2，Wooden Shoe熔结凝灰岩覆盖面积≥ 4400 km~2，并延伸到内华达州。在11.9~12.8 Ma之间，该地区大规模爆发的平均频率为每354千公里1次，约为黄石公园的两倍。早期流纹岩的化学和矿物学表明，随着时间的推移，其成熟度逐渐增加，这可能是由于渐进的分步结晶作用。其次是一个趋势，向较少发展的韵律，可能记录熔融和杂交的中地壳源区。同期岩浆活动引起的地壳沉降的蛇河流域中部记录连续熔结凝灰岩的剥离和变薄的区域盆地边缘的单斜，这发展之间的10.59和8马的N-面向肢体。同火山盆地的地形与现今升高的黄石热点高原形成鲜明对比。同时盆地和山脉的伸展产生了N向Rogerson地堑：肖肖尼山的早期隆起（≥ 10.34 Ma），随后是肖肖尼断层和E向倾斜的半地堑（10.3 - 10.1 Ma）的开始。地堑的不对称性随后随着布朗阶断层（≥ 8 Ma）的形成而逆转，该断层直到上新世仍间歇性活动。
Rogerson Graben, USA, is critically placed at the intersection between the Yellowstone hotspot track and the southern projection of the west Snake River rift. Eleven rhyolitic members of the re-defined, ≥420-m-thick, Rogerson Formation record voluminous high-temperature explosive eruptions, emplacing extensive ashfall and rheomorphic ignimbrite sheets. Yet, each member has subtly distinct field, chemical and palaeomagnetic characteristics. New regional correlations reveal that the Brown’s View ignimbrite covers ≥3300 km2, and the Wooden Shoe ignimbrite covers ≥4400 km2and extends into Nevada. Between 11.9 and ∼8 Ma, the average frequency of large explosive eruptions in this region was 1 per 354 ky, about twice that at Yellowstone. The chemistry and mineralogy of the early rhyolites show increasing maturity with time possibly by progressive fractional crystallisation. This was followed by a trend towards less-evolved rhyolites that may record melting and hybridisation of a mid-crustal source region. Contemporaneous magmatism-induced crustal subsidence of the central Snake River Basin is recorded by successive ignimbrites offlapping and thinning up the N-facing limb of a regional basin-margin monocline, which developed between 10.59 and 8 Ma. The syn-volcanic basin topography contrasted significantly with the present-day elevated Yellowstone hotspot plateau. Concurrent basin-and-range extension produced the N-trending Rogerson Graben: early uplift of the Shoshone Hills (≥10.34 Ma) was followed by initiation of the Shoshone Fault and an E-sloping half-graben (∼10.3–10.1 Ma). The graben asymmetry then reversed with initiation of the Brown’s Bench Fault (≥8 Ma), which remained intermittently active until the Pliocene.
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影响因子：
4.9
作者：
G. Andrews;M. Branney
通讯作者：
G. Andrews;M. Branney
蛇河平原东部和黄石隆起的地壳速度结构
DOI：
--
发表时间：
1998
期刊：
影响因子：
--
作者：
Xiaohua Peng;E. Humphreys
通讯作者：
E. Humphreys
影响因子：
5.8
作者：
G. Robert;G. Andrews;Jiyang Ye;A. Whittington
通讯作者：
A. Whittington
影响因子：
4.5
作者：
S. Self;S. Blake
通讯作者：
S. Blake
美洲狮点凝灰岩：对中新世黄石热点地区高温大体积硅质岩浆热化学分带和寿命的影响
DOI：
--
发表时间：
2004
期刊：
影响因子：
--
作者：
H. Cathey;B. Nash
通讯作者：
B. Nash