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Lomas S A. Cretaceous Research, 1998, 19(1):<br />
43-67<br />
The Byers Group, exposed in the western<br />
South Shetland Islands, is a thick (at least 2.7<br />
km) succession recording Late Jurassic–Early<br />
Cretaceous sedimentation and volcanism on<br />
the Pacific flank of the Antarctic Peninsula<br />
magnetic arc. At least 1.3 km of marine clastic<br />
rocks are overlain by 1.4 km of non-marine<br />
strata. Penecontemporaneous, mainly intrusive,<br />
igneous rocks are present in much of the succession.<br />
At the base of the Byers Group, radiolarian-rich,<br />
hemipelagic mudstones of the<br />
Kimmeridgian–Tithonian Anchorage Formation<br />
are succeeded by terrigenous, slope-apron<br />
mudstones and sandstones of the Berriasian<br />
President Beaches Formation. These deepmarine<br />
strata are overlain by shallower-marine<br />
conglomerates and mudstones of the Berriasian–Valanginian<br />
Chester Cone Formation.<br />
The upper part of the marine succession also<br />
includes the volcanic breccias of the Start Hill<br />
Formation, interpreted as part of a debrisapron<br />
flanking a substantial volcanic edifice.<br />
Finally, following a Valanginian–Aptian erosional<br />
hiatus, non-marine volcaniclastic rocks<br />
of the Cerro Negro Formation were deposited<br />
in early Aptian times. Comparison with timeequivalent<br />
successions elsewhere in the Antarctic<br />
Peninsula region suggests that within<br />
the overall regressive trend, the Byers Group<br />
records regionally significant pulses or arc<br />
uplift in Tithonian–earliest Berriasian, latest<br />
Berriasian, and late Valanginian–Earliest Aptian<br />
times.<br />
2008010495<br />
美 国 Lima Peaks 地 区 到 蒙 大 拿 和 爱 荷 华 西<br />
南 部 Madison Range 地 区 的 上 白 垩 统 地 层<br />
对 比 = Correlation of Upper Cretaceous strata<br />
from Lima Peaks area to Madison Range,<br />
southwestern Montana and southeastern Idaho,<br />
USA. ( 英 文 ). Dyman T S; Tysdal R G; Perry<br />
W J; Obradovich J D; Haley J C; Nichols D J.<br />
Cretaceous Research, 1997, 18(6): 751-766<br />
An 40 Ar/ 39 Ar age of 85.81 Ma±0.22 my<br />
was obtained on sanidine from a volcanic procellanite<br />
bed near the top of the 2135+m-thick<br />
Upper Cretaceous Frontier Formation in the<br />
Lima Peaks area of southwestern Montana.<br />
This early Santonian age, combined with previously<br />
determined age data including a palynological<br />
age of Cenomanian for the lower<br />
Frontier at Lima Peaks, and a U-Pb isotopic<br />
date of about 95 Ma for the base of the Frontier<br />
Formation in the eastern Pioneer Mountains<br />
north of the Lima Peaks area, provides<br />
an age range for the nonmarine formation. In<br />
the Madison Range, farther east in southweastern<br />
Montana, this age range corresponds<br />
to marine strata of not only the Frontier Formation,<br />
but also the overlying Cody Shale and<br />
Telegraph Creek Formation, a sequence that<br />
totals less than 760 m thick.<br />
The Upper Cretaceous marine formations<br />
of the madison Range are closely zoned by<br />
molluscan faunas that are well constrained<br />
with radiometric dates. The 40 Ar/ 39 Ar age of<br />
85.81 Ma±0.22 my at Lima Peaks is bracketed<br />
by radiometric dates for theScaphites depressus—Protexanites<br />
bourgeoisianusbiozone and<br />
the overlying Clioscaphites saxitonianus—<br />
Inoceramus undulatopilcatusbiozone of the<br />
Western Interior. Fossils of both of these biozones<br />
are present in the Cody Shale and the<br />
Telegraph Creek Formation in the Madison<br />
Range. The Telegraph Creek contains two<br />
units of volcanic ash that are approximate time<br />
equivalents of the volcanic procellanite of the<br />
Lima Peaks area. Clasts in the conglomerate<br />
of the upper part of the Frontier in the Lima<br />
Peaks area were shed during the initial stages<br />
of uplift of the Blacktail-Snowcrest Highlands<br />
which rose to the north. The dated porcellanite<br />
lies above the conglomerates and indicates<br />
that the uplift was initiated by middle or late<br />
Coniacian, 87–88 Ma.<br />
2008010496<br />
塔 里 木 盆 地 西 南 地 区 上 白 垩 统 生 物 丘 =<br />
Upper Cretaceous rudist bioherms in south<br />
western Tarim. ( 中 文 ). 彭 阳 ; 郭 宪 璞 ; 王 易 农 ;<br />
丁 孝 忠 . 地 质 通 报 , 2002, 21(2): 83-87 1 图 版 .<br />
塔 里 木 盆 地 西 南 部 昆 仑 山 前 缘 地 区 上 白<br />
垩 统 依 格 孜 牙 组 中 发 育 一 套 固 着 蛤 生 物 丘 ,<br />
横 向 上 由 西 向 东 沿 阿 克 彻 依 、 乌 依 塔 克 、<br />
依 格 孜 牙 、 吐 依 洛 克 、 阿 尔 塔 什 至 莫 莫 卡<br />
一 线 呈 串 珠 状 展 布 。 丘 基 下 部 为 潜 在 的 生<br />
油 岩 — 藻 泥 晶 灰 岩 , 上 部 为 生 物 碎 屑 滩 , 主 体<br />
丘 核 为 簇 状 固 着 蛤 灰 岩 , 丘 顶 藻 席 可 见 清 楚<br />
的 上 超 。 生 物 丘 下 伏 地 层 及 盖 层 均 为 膏 泥<br />
岩 , 形 成 了 一 个 顶 底 圈 闭 。<br />
2008010497<br />
辽 北 早 白 垩 世 泉 头 组 沉 积 体 系 = Study of<br />
the sedimentary system of the Early Cretaceous<br />
Quantou Formation in northern Liaoning.<br />
( 中 文 ). 周 勇 ; 胡 晋 伟 ; 李 东 涛 . 地 质 通<br />
报 , 2002, 21(3): 144-149<br />
通 过 辽 北 早 白 垩 世 泉 头 组 地 层 研 究 , 提 出<br />
泉 头 组 沉 积 层 序 划 分 方 案 : 划 分 为 2 个 层<br />
序 ,11 个 旋 回 层 序 ,20 个 基 本 层 序 ; 总 结 了 层<br />
129
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