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71.
72.
河北牛驼镇地热田高温地热水成因分析 总被引:1,自引:0,他引:1
牛驼镇地热田以基岩热储层最优,是目前地热田开发利用条件最好的热储层。牛驼镇基岩热储水温60℃~100℃,顶板埋深最浅处小于500m,一般为800~1500m,涌水量50~110 m3/h。基岩地热水水化学类型为Cl—Na型水,偏硅酸浓度46~92mg/L,偏硼酸浓度5.0~33 mg/L,氟浓度5.41~11 mg/L,是优质的理疗矿泉水。本文着重从构造运动的角度分析了牛驼镇高温地热水的形成。阐述了自元古代的吕梁运动开始至二叠纪期间,研究区在经过"三降两升"的五个地史发展期中不仅沉积了良好的基岩热储层,亦储藏了丰富的水源。随着新生代喜山运动的活跃,在牛东等断裂的控制下,牛驼镇凸起发育成熟,在此过程中,牛驼镇凸起暴露地表,沉积了新近系和第四系,构成基岩热储的良好盖层。另外,由于基岩热储岩性的热导率较高及埋藏深度较浅,使得牛驼镇地热田拥有相对较高温度的地热水资源。 相似文献
73.
Study of Influence of Regional Geodynamic Background on Strata Behaviors in China's Tongxin Mine 下载免费PDF全文
Strata behaviors are mainly affected by regional geodynamic background. The influence of rock mass stress and energy distribution on strata behaviors in the Tongxin mine is studied in terms of regional tectonic movement, seismic activity and tectonic stress field. The results show that the extrusion lifting movement of Kouquan fault adjacent to the Tongxin mine results in the stress concentration in the rock of the Carboniferous coal bed and accumulation of a large amount of elastic energy and forms structural background of Tongxin mine. Due to various seismic activities in the mine area, the strain energy is known to reach much higher levels, up to 0.5×108 J1/2. Since the stratigraphic structure is sensitive to the mining operation, the strain energy could cause strong strata behaviors. A special geological structure model of the Tongxin mine is established based on the geodynamic division method. The distribution of regional structure stress field is determined by the rock mass stress analysis system. Based on this model, Tongxin mine is divided into five areas with high stress, eight areas with low stress and eight areas with gradient stress. The strong strata behaviors mostly occur in high stress areas. These results could provide guidance to predict the strength of regional or mine pressure and control strata behavior in different areas. 相似文献
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75.
西秦岭上白垩统红层空间分布及其对青藏高原东北缘隆升的地质约束 总被引:2,自引:0,他引:2
通过对西秦岭上白垩统红层地层基本沉积特征的研究和空间高程分布的定量化分析,讨论了西秦岭晚白垩世时期可能的构造地貌状态及西秦岭新生代以来地壳隆升的空间变化规律。取得如下认识:1根据西秦岭上白垩统底部洪积-冲积砾岩层之上普遍存在一套厚度不等的具有风成砂岩特征的红色中细粒砂岩和上部出现以泥岩、泥质粉砂岩为主的湖相沉积,结合现今多分布在不同水系分水岭之上,以及西秦岭中部宕昌-岷县-临潭断裂带两侧上白垩统红层地层顶面高程和底部角度不整合面高程没有显著差异分析,认为西秦岭无论在晚白垩之前经历了何种构造过程,晚白垩世具有整体稳定的泛沙漠-湖盆的古构造地貌状态,且断裂带不具备控制上白垩统沉积的构造边界性质;2现今离散型分布在西秦岭的上白垩统沉积地层反映的原型盆地不是孤立的、受区域断裂控制的山间盆地,而是统一的泛沙漠-内陆湖盆,现今的离散型分布是新生代以来地壳不均匀隆升和侵蚀的结果;3西秦岭上白垩统底部的角度不整合面产状,虽然由于后期构造变动呈非完全水平状态,但总体产状平缓。从大区域尺度分析,可以近似看做原始近水平的古地貌面。通过对该角度不整合面高程信息提取和模拟分析,结果表明,其高程分布具有从南西到北东、从北西到南东逐渐降低,穿越区域断裂带没有显著梯度变化,指示了西秦岭新生代以来的隆升具有整体性和隆升幅度呈连续梯度变化的特征。这可能指示了西秦岭新生代以来的地壳隆升机制主要不是上地壳挤压逆冲缩短,而是在印度板块-欧亚板块碰撞汇聚的动力学背景下,下地壳或上地幔自西南向北东连续流变逐渐增厚,造成了青藏高原东北缘呈向北东突出的弧形扩展隆升。 相似文献
76.
新疆乌恰萨热克铜矿北矿带库孜贡苏组沉积相、古流向、物源区及其找矿意义——来自砾石统计分析的证据 总被引:1,自引:1,他引:0
萨热克盆地库孜贡苏组是萨热克铜矿的赋矿层位,开展沉积相、物源区及古流向研究对隐伏铜矿的勘探具有重要意义。选取萨热克铜矿北矿带库孜贡苏组地表矿化最好的砾岩展开砾石统计分析,结果表明,偏斜度显示砾岩为冲积扇相沉积,砾石叠瓦状和砂岩斜层理产状统计显示古流向为北北东向;砾石成分主要为石英、石英砂岩、砂岩,石英岩等;粒度分布呈宽峰态或尖峰态;物源区为元古宇长城系阿克苏群变质岩剥蚀区;物源补给分为主河流补给和支河流补给2种方式。冲积扇相、古流向、物源区分析确定了矿体的范围、最优的勘探线布置方位和潜在的找矿靶区,具有很好的勘探意义。 相似文献
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78.
This paper examines the distribution of unconsolidated sediment in the KwaZulu-Natal Bight located along the east coast of South Africa. Results show that there is a general shelf-wide sediment distribution of coarser grain sizes between depths of 60 and 100?m, punctuated by a broad swathe of mud offshore of the Thukela River. Seasonal changes in sediment distribution patterns are small, being restricted to seaward fining on the inner shelf off the fluvial sources. Sediment distribution reflects a partitioning between sediment populations that are current- influenced and relict (palimpsest) populations associated with submerged shorelines. Wave ravinement during the deglacial transgression, the reworking of submerged shorelines during sea-level stillstands and, to a lesser extent, the Agulhas Current system, are the dominant controls on sediment distribution. 相似文献
79.
Late Cenozoic Sedimentary Evolution of Pagri‐Duoqing Co graben,Southern End of Yadong‐Gulu Rift,Southern Tibet 总被引:1,自引:0,他引:1
The north trending rifts in southern Tibet represent the E–W extension of the plateau and confirming the initial rifting age is key to the study of mechanics of these rifts. Pagri–Duoqing Co graben is located at southern end of Yadong–Gulu rift, where the late Cenozoic sediments is predominately composed of fluvio-lacustrine and moraine. Based on the sedimentary composition and structures, the fluvio-lacustrine could be divided into three facies, namely, lacustrine, lacustrine fan delta and alluvial fan. The presence of paleo-currents and conglomerate components and the provenance of the strata around the graben indicate that it was Tethys Himalaya and High Himalaya. Electron spin resonance (ESR) dating and paleo-magnetic dating suggest that the age of the strata ranges from ca. 1.2 Ma to ca. 8 Ma. Optically stimulated luminescence (OSL) dating showed that moraine in the graben mainly developed from around 181–109 ka (late Middle Pleistocene). Combining previous data about the Late Cenozoic strata in other basins, it is suggested that 8–15 Ma may be the initial rifting time. Together with sediment distribution and drainage system, the sedimentary evolution of Pagri could be divided into four stages. The graben rifted at around 15–8 Ma due to the eastern graben-boundary fault resulting in the appearance of a paleolake. Following by a geologically quiet period about 8–2.5 Ma, the paleolake expanded from east to west at around 8–6 Ma reaching its maximum at ca. 6 Ma. Then, the graben was broken at about 2.5 Ma. At last, the development of the glacier separated the graben into two parts that were Pagri and Duoqing Co since the later stages of the Middle Pleistocene. The evolution process suggested that the former three stages were related to the tectonic movement, which determined the basement of the graben, while the last stage may have been influenced by glacial activity caused by climate change. 相似文献
80.
内蒙古1∶5万乌音呼日勒庙等四幅区域地质矿产调查项目取得的新进展及主要成果为: 根据岩石组合、动植物化石及同位素年龄等,重新厘定、划分了16个岩石地层填图单位,在多个组段沉积岩层位中首次发现丰富的动、植物化石,建立了各地层年代学格架; 将侵入岩重新解体划分为4个填图单元,并建立了侵入岩年代学格架; 新发现1处规模较大的韧性变形带,主要为逆—左行走滑韧性断层,时代归属于中三叠世末期,为额尔古纳河—阿龙山NE向韧性变形域的南部延伸; 新发现矿(化)点20处,其中金属矿点3处,金属矿化点6处,非金属矿点9处,非金属矿化点2处; 总结了该区成矿规律,圈定了成矿远景区及找矿靶区。 相似文献