Tertiary Rocks Research Articles

Introduction to the special issue of Canadian Journal of Earth Sciences: The Nechako NATMAP Project of the central Canadian Cordillera

The Canadian Cordillera in central British Columbia has seen the Mesozoic subduction of an oceanic terrane; the amalgamation of volcanic-arc terranes; continued intermittent Mesozoic compression and magmatism; and Tertiary wrenching, extension and magmatism. Except in its northernmost mountain ranges, the area is extensively covered in glacial drift and thin veneers of Tertiary volcanic rocks. In 1994, a group of scientists and technologists believed they could understand that cover, see through it, and discover the components of that collision and extensional orogen. They would apply modern techniques of isotopic and paleontological geochronology; lake-sediment, till, and plant geochemistry; detailed gravity, magnetic, radiometric, paleomagnetic, and electromagnetic surveys; and isotopic and trace element lithochemistry, as they conducted extensive bedrock and surficial mapping. This special issue summarizes a cross-section of the scientific contributions derived from that mapping conducted under the auspices of the Nechako NATMAP Project. It demonstrates the absolute necessity of applying modern isotopic and paleontologic geochronology to understand the Phanerozoic geology of the Cordillera. It emphasizes the necessity of detailed aeromagnetic surveys (500 m or less line spacing) in looking through covered terranes at anything more than 1 : 250 000 scale. And, it shows the immense utility of applying various geochemical techniques to solve geological problems and establish baselines for future research and economic development. Bedrock and surficial mapping in the central Cordillera, using these and other techniques, have established the nature and timing of Mesozoic crustal growth, Tertiary crustal thinning, and the associated formation of mineral deposits.

Saline wetlands related to groundwater flows from low permeability Tertiary formations in the Somontano area of Huesca, Spain

AbstractPresence of groundwater flow in the ‘Somontano de Huesca’ Area, derived from low‐permeability detrital Tertiary rocks, is considered. A groundwater flow model is constructed for these Tertiary rocks. This model explains both water flow through them and the chemical characteristics of the water.Groundwater flow has clear surface manifestations: it causes wetlands (which are called ‘paules’ in the area) with sodic waters, it produces saline, sodic or alkaline soils, and it produces modifies the chemical composition of rivers in Somontano.Irrigation has increased the volume of filtered water, especially in the interfluve areas, causing the extension of the wetlands in the valley thalwegs, and also the greater movement of salts has increased the problems of saline and/or sodic soils in the area. Copyright © 2001 John Wiley & Sons, Ltd.

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We present a comprehensive statistical analysis of petrophysical properties of rocks of the northeastern Rhenish Massif and the Lower Rhine Embayment in Germany. Properties measured comprise thermal conductivity, specific heat capacity density, porosity, hydraulic permeability, and compressional wave velocity. This robust and statistically reliable data is generally useful for numerical modeling of heat transport processes and helps, in particular, reducing the risk of failure in projects of geothermal energy use. We measured the thermophysical properties of rocks from two geological settings: (1) predominantly little consolidated Tertiary rocks forming the young sedimentary cover of the Lower Rhine Embayment in the condition they arrived in the laboratory; (2) well consolidated Paleozoic rocks from the northeastern Rhenish Massif in both dry and saturated condition. We tested a total of 476 samples from different lithologies in both settings in a comprehensive laboratory program consisting of mineralogical analyses and various petro- and thermophysical measurements at ambient and elevated p-T-conditions. This yields relations between composition and thermophysical properties of different sedimentary rock types and allows distinguishing between effects due to rock matrix and structure. The results are used to prove petrophysical rock models and allow predicting thermal properties of distinct rock types for greater depth. The results show that the thermophysical properties of Paleozoic rocks are mainly controlled by their mineralogical compositions, while thermophysical characteristics of Tertiary rocks are the result of a superposition of properties of their mineral content and the water-filled pore volume.

Geometry and distribution of regional joint sets in a non-homogeneous stress field: case study in the Ebro basin (Spain)

Three regional joint sets striking N–S, E–W and WNW–ESE affect the Tertiary rocks of the central Ebro basin. From analysis of their chronological relationships and spatial distribution, it is concluded that they correspond to two different tectonic events. The N–S set (oldest) and the E–W set (younger) are present in the southern and central sectors, while the WNW–ESE joint set predominates in the northern one. The N–S joints propagated in response to joint-normal and fluid loads under an intraplate stress field with S Hmax oriented near N–S (related to forces caused by the convergence of Africa, Iberia and Europe and rifting at the Valencia trough) during the sedimentary infilling of the basin. These joints are only present in the southern part of the area. The E–W joint set in the southern-central sector records the same fracturing event as the WNW–ESE set does in the northern one. Its orientation was modified by the presence of the older N–S set in the south, which perturbed the regional stress field. The younger WNW–ESE and E–W joint sets are interpreted as unloading joints. These propagated as a consequence of flexural uplift and exhumation related to isostatic rebound at the Pyrenees and the Ebro foreland basin. A numerical approach is used to explain the inhomogeneous distribution of the N–S joint set in terms of their absence being controlled by the depth of the water table at the time of their formation.

GIS-based landslide hazard mapping in the Scotland District, Barbados

Rationale The Scotland District occupies an area of approximately 60 km 2 forming the northeast coastline of Barbados (Fig. 1). The district is geologically and topographically distinct from the rest of Barbados in that the coral limestone cap that covers the remainder of Barbados is absent. The underlying Tertiary rocks exposed in the Scotland District are soft and erodible, and are themselves prone to landsliding and erosion. Land use in the district comprises forest, sugar cane, fruit and vegetable growing and pasture, and the district has high landscape value and eco-tourism potential. Low rise, low density housing has developed over the decades, predominantly along cart tracks and roads with alignments that tend to follow ridge and spur lines in an attempt to avoid potentially unstable side-long ground. However, there are numerous locations where erosion and ground movements have caused significant distress to road pavements, and where foundations to residential buildings have been undermined to the extent that some areas have been abandoned altogether. The Soil Conservation Unit (Ministry of Agriculture and Rural Development) has been tackling slope instability and erosion problems in the district for over half a century. A number of useful projects have been commissioned to examine and remediate areas of known ground instability, and several schemes involving drainage and earthworks have proved successful. However, realizing that there were several geological, topographical, drainage and land use factors distributed throughout the district that had a role to play in the pattern of ground instability and erosion.

Palynostratigraphy of the tertiary sediments in north-east India with comments on the terminal eocene events

The Tertiary rocks in North-East India rest unconformably on the granitic basement. They represent more or less a continuous sequence except a post Barail unconformity. The palynological assemblage is more or less known from all the formations. The assemblage by and large is dominated by the pteridophytic spores in all the formations followed by the angiospermic pollen. The gymnospermic pollen are rare in Palaeocene-Middle Eocene and are found in Late Eocene onwards and occur in good numbers in Miocene-Pliocene rocks. The index fossils for each formation have been marked. The Terminal Eocene events have been analysed. It has been observed that during that time India was enjoying a tropical climate and there was no cooling effect as has been advocated from the other parts of the world.

Palynology in stratigraphy of lesser Himalayan sedimentary sequences from Arunachal Pradesh, India

Arunachal Pradesh has a distinct geological setup and significant data have been generated during the last decade both from Permian as well as Tertiary sediments. The palynoflora investigated from Lesser Himalayan Permian sediments of Arunachal Pradesh has been differentiated into five palynozones 1. Plicalipollenites stigmatus 2. Callumispora gretensis 3. Crucisaccites indicus 4. Pselldoreticulatispora baraknrensis and 5. Primuspollenites + Rhizomaspora: the oldest being Palynozone I (Rilu Member, Rangit Formation) representing Late Asselian whilc Palynozones 2-5 (Garu Formation) represent Early Sakmarian to Early Artinskian age.
 The palynoassemblages recorded from Tertiary sediments in Arunachal Pradesh largely show the overwhelming presence of angiosperm pollen. viz. Lakiapollis. Neocouperipollis, Arecipites, Pellicieroipollis and Ctenolophonidites. Pteridophytic spores. viz., Todisporites. Cyathidites. Striatriletes and Crassoretitriletes shows similar age connotations. Broadly two distinct palynozones have been differentiatcd. viz., Lakiapollis ovatus and Striatriletes susannae assemblage zones. At some sections presence of dinoflagellate and acritarch indicate marine influence during Early Tertiary.
 Permian spores also occur in reworked state within Early Tertiary sediments. Palynological investigations carried out along the thrust suggest that some thrust slices of Tertiary rocks arc wedged deep within the Permian outcrops. These evidences indicate severe post depositional tectonic effect in these regions. Palynological evidences along with faunal evidences. Wherever possible, have been summarised to decipher the stratigraphic resolutions, palaeogeography and palaeoenvironment of the region.

Pre-ocean opening compression of the Northwestern Atlantic margin: evidence from eastern North Greenland

The deformation of the Wandel Sea Basin of eastern North Greenland and the West Spitsbergen Fold Belt are the result of Late Cretaceous–Palaeocene Greenland–Barents Sea/Svalbard convergence following the opening of the Labrador Sea–Baffin Bay opening. The Tertiary rocks of the Wandel Sea Basin are undeformed while the Late Palaeozoic–Mesozoic are weakly folded and thrust faulted. Thrust fault movements in North Greenland ceased before Mid-Palaeocene time when the dextral motion separating Greenland and Svalbard began. The shortening was orthogonal to the continental margin and a transpressional origin for the deformation of the Wandel Sea basin is not confirmed.

Mapping Soil Geochemical Anomalies in the Mesa Quadrangle, Arizona, Using NURE Data

Maps showing anomalously high concentrations of 13 different elements in soils within the Mesa Quadrangle of southern Arizona were constructed using information contained in the National Uranium Resource Evaluation (NURE) database. Existing geochemical databases such as NURE provide an inexpensive and accessible resource that can be used to characterize an area geochemically. Anomalies in soils were determined after applying descriptive statistics, logarithmic transformations, elimination of outliers, and manipulation of below-limit detection values. Among the elements with the most number of anomalies, Cu clustered in the southcentral part of the quadrangle where porphyry copper deposits are located, while As, Be, Co, Cr, Zn, Th, and U anomalies were located over exposed Precambrian and Tertiary igneous rocks. In general, anomalies could be related to the rocks cropping out, type of soils, and several mines present in the area.

Uniaxial compression strength and erosive potential rate of rocks in strata on the coast of Miura Peninsula with specific relation to the algal communities of Eisenia bicyclis and Ecklonia cava

SUMMARY: To clarify the physical properties of the rock substratum on which algal communities of Eisenia bicyclis and Ecklonia cava are found, studies were conducted on: (i) strata on the coast of the Miura Peninsula; (ii) uniaxial compression strength and erosive potential rate of the substratum; and (iii) bond strength of Eisenia bicyclis classified by location. Sea beds and rock strata lying immediately off promontories and coves with lush algal growth were identified at Bokke-zaki (Misaki Formation: Ms), Jyogashima Island (Hatsuse Formation: Ht), Ara-saki (Ms), Kawajiribana (Zushi Formation: Zs), and Chojyaga-saki (Zs). These have all been verified as belonging to the late Miocene (Miura Group). The compression strengths (kgf/cm 2) of rocks at Ms, Zs and Ht were 73.0, 86.2 and 148.9, respectively. Erosive potential rates (%/h) of Ms, Zs and Ht strata were 4.47 × 10−2, 3.64 × 10−2 and 2.09 × 10−2, respectively. Bond strengths of Eisenia bicyclis to the substratum (kg) on Ms, Zs and Ht strata were 25.3, 27.4 and 23.1, respectively. Rocks of the Quaternary (Miyata Formation: My) with no algal community were found to be much more brittle than those in the Tertiary period. Conversely, concrete blocks were very rigid, but bond strength of Eisenia bicyclis was as low as 50% compared to Tertiary period rock. It can be seen from the observations above that the geological properties and the nature of the late Miocene rocks are the most favourable substratum for algal communities of Eisenia bicyclis and Ecklonia cava.

FIRST RECOGNITION OF THE CHEIRAGONIDAE (DECAPODA) IN THE FOSSIL RECORD AND COMPARISON OF THE FAMILY WITH THE ATELECYCLIDAE

Abstract Newly recovered fossils from the Eocene Hoko River Formation of western Washington, USA, constitute the first recognized occurrence of the Cheiragonidae Ortmann in the fossil record. The Cheiragonidae are recognized as a distinct family and are clearly distinguished from the Atelecyclidae Ortmann based on numerous characteristics of the dorsal carapace, appendages, sternum, and chelipeds. The genus Montezumella Rathbun is removed from the Atelecyclidae and placed within the Cheiragonidae. The reassignment of Montezumella to the Cheiragonidae extends the known occurrence of the family into the late Eocene. Montezumella eichhorni n. sp., Trichopeltarion granulosa n. sp. are recognized from Tertiary rocks of Washington, and Trichopeltarion merrinae n. sp. is recognized from late Miocene rocks of New Zealand.

Geothermal resources of Hachijojima

Hachijojima is a gourd-shaped volcanic island in the Pacific Ocean. Nishiyama and Higashiyama volcanoes consist of basalt lava and associated pyroclastic rocks. A promising geothermal resource was found in south Higashiyama, associated with an uplift of Tertiary rocks consisting of mainly andesite lava and related pyroclastic rocks, overlain by Quaternary volcanic rocks. Steep high-temperature (over 250°C) and high-pressure gradients occur in the deeper portion of the system near the Tertiary–Quaternary contact, indicating the presence of a cap rock. The cap rock formed by deposition of hydrothermal minerals. Geothermal fluid ascends from the deeper portions to shallow depths along vertical fractures through the cap rock. These vertical fractures form the geothermal reservoir in the Tertiary formation. Three wells were drilled into these vertical fractures, and approximately 30 t/h of superheated steam was obtained from each well during flow tests. The geothermal fluid is mainly a mixture of seawater and meteoric water in an approximate ratio of 1 to 2, based on chemical analyses, with a portion of volcanic gas included. At present a 3.3 MW e, geothermal power plant is being constructed here.

Reconstructing early Himalayan tectonic evolution and paleogeography from Tertiary foreland basin sedimentary rocks, northern India

Reconstructing early Himalayan tectonic evolution and paleogeography from Tertiary foreland basin sedimentary rocks, northern India

Nature of the southwestern boundary of the central Mojave Tertiary province, Rodman Mountains, California

Tertiary volcanic and sedimentary rocks in the central Mojave Desert are largely confined to the Barstow-Bristol trough, an elongate tectonic depression filled with lower Miocene strata. The southwestern boundary of the trough is sharply defined and separates thick (∼2 km) Tertiary sequences from an area to the southwest that is virtually devoid of Tertiary rocks. Segments of this boundary have been interpreted as a buttress unconformity, as a right-slip sidewall fault that formed the lateral boundary of an early Miocene extensional terrane, and as a dip-slip fault caused by flexure of the North American plate above the subducted Mendocino fracture zone. The Silver Bell fault in the Rodman Mountains, central Mojave Desert, is the best exposed segment of the boundary, and relations exposed along it can be used to test these hypotheses. The Tertiary sequence north of the Silver Bell fault is at least 2.3 km thick and comprises at least 1.9 km of mafic lava flows overlain by and intercalated with coarse clastic rocks derived from the south side of the fault. Stratigraphic relations require faulting during volcanism and indicate that the minimum throw across the fault is at least equal to the thickness of the exposed Tertiary section. Tuff layers intercalated in the lower part of the clastic deposits are 23–24 m.y. old, indicating that faulting and volcanism were contemporaneous with extension and plutonism in the nearby central Mojave metamorphic core complex. Structural and stratigraphic data indicate that the Silver Bell fault is primarily a dip-slip fault. The Tertiary section is folded into a west-trending, upright to overturned syncline located near the southern edge of exposed Tertiary rocks. The syncline records late Cenozoic north-south shortening along the northwest-striking Calico fault, which in this area accommodated about 10 km of right slip and perhaps 1 km of reverse slip. Southwestward-dipping strata in the areally extensive north limb of the syncline resemble tilted strata in nearby highly extended areas and have been interpreted to reflect crustal extension. However, bedding dip does not decrease upward in the Tertiary section, paleocurrent directions trend obliquely updip, and northeast-dipping normal faults are rare. Stratal tilting postdated the accumulation of the exposed section, which therefore was not deposited during rotational normal faulting. The new data contradict interpretation of the Silver Bell fault as a major right-slip fault bounding the central Mojave extensional terrane, although they permit small-magnitude extension across the fault. The amount of early Miocene crustal extension in this area therefore is apparently small in spite of stratal tilting, and the lateral limit of large-magnitude crustal extension in the central Mojave block is farther northwest. The data are consistent with the fault having formed by failure during plate flexure above the subducted Mendocino fracture zone.

Tectonic assembly of east-central Alaska: Evidence from Cretaceous–Tertiary sandstones of the Kandik River terrane

East-central Alaska is a tectonically significant region between parautochthonous North America and the Arctic Alaska terrane to the north. The tectonic evolution of the area is recorded in Late Jurassic to early Tertiary sedimentary rocks of the Kandik River terrane. Fine-grained clastic rocks deposited in the area from Late Jurassic to Valanginian time represent a continuation of the passive margin sequence that persisted since the late Precambrian on the nearby North American margin. A pulse of quartz arenites (sandstones in the uppermost Glenn Shale and the Keenan Quartzite) reflects Valanginian rift-shoulder uplift, marking initiation of crustal upwarping and thinning that would later lead to the opening of the Canada basin. Fine-grained turbidites interpreted as distal submarine fan deposits (Biederman Argillite), Valanginian to possibly as young as Aptian, were next deposited along the passive margin. These quartz wackes contain framework grains with the same continental source as the quartz arenites, but geochemical evidence points to arc detritus in the fine-grained (pelagic) intervals. Compressional tectonics began in the Aptian, and are recorded by arc-derived volcaniclastic turbidites (Kathul Graywacke) that were quickly overthrust, buried to depths of 5–8 km, then uplifted and eroded in the Late Cretaceous. These events record the accretion of a previously unreported island arc to the Porcupine and Kandik River terranes, followed by accretion of this complex to North America. A second orogenic event followed in the latest Cretaceous to early Tertiary, when extension, possibly associated with emplacement of Yukon-Tanana terrane along the Tintina fault to the south, produced a half graben (Nation River basin) and a pull-apart basin that were filled with litharenites derived from local sources (unit TKs). These deposits were broadly uplifted and warped in the middle Tertiary, probably by regional Laramide-age events. These results are significant in that they provide evidence for a previously unreported Aptian–Albian volcanic arc in east-central Alaska. In addition, comparison of sedimentation events in east-central Alaska with those recorded in the North Slope sequence of northern Alaska provides constraints on tectonic models for the evolution of northern Alaska.

Isotopic evidence for the sources of Cretaceous and Tertiary granitic rocks, east-central Alaska: implications for the tectonic evolution of the Yukon-Tanana Terrane

Isotopic evidence for the sources of Cretaceous and Tertiary granitic rocks, east-central Alaska: implications for the tectonic evolution of the Yukon-Tanana Terrane

Overview of the Geology and Mineral Industry of Nicaragua

This paper is a synthesis and update of the geology of Nicaragua and a discussion of metallic and non-metallic mineral deposits. Nicaragua is divided into 15 departments and 2 autonomous territories, within an area of 130,700 km2. The geologic environments include Paleozoic crystalline basement rocks, Mesozoic sedimentary and intrusive rocks, nearly continuous sedimentary sequences of Late Cretaceous to Pleistocene age, a broad area of Tertiary volcanic rocks, and Quaternary sedimentary and volcanic rocks that include several active volcanoes. These rocks have a dominant continental crust affiliation and are assigned to the Chortis Block, although there is evidence of fragments of oceanic-crust material. The structural framework is controlled largely by the NW-trending Middle America Trench, which marks the boundary between the Cocos and Caribbean plates. This trend is manifest in the Nicaraguan Depression, the chain of volcanoes that extend from western Panama to El Salvador, as well as fold axes within a forearc depositional basin. East of the Nicaraguan Depression, a northeast structural trend becomes important. There are some 94 metallic and 46 nonmetallic mineral deposits within the various geologic environments. Gold is mined from three deposits—Limon, Bonanza, and La Libertad—and limestone, gypsum, aggregates, and clay minerals are mined at six quarries. Nicaragua is the leading gold-producing country in Central America and the Caribbean Basin. Since the late 1930s more than eight million ounces of gold have been mined, mainly from epithermal and mesothermal veins (Limon, Bonanza), skarn zones (Siuna, Rosita), and various placer deposits. Geologic reserves are estimated at 6.5 million ounces. Other mineral commodities include silver, copper, zinc, limestone, aggregates, gypsum, and clay minerals. Brief descriptions of these and several other commodities are provided along with production statistics and general location maps. As a result of political unrest and nationalization of many foreign assets during the 1970s and 1980s, little exploration was conducted. However, the election of a stable, democratic government in the early 1990s and a revision of foreign investment regulations has resulted in an increase in exploration activity; nevertheless, much of the country remains underexplored.

Post-Miocene subtropical karst evolution, lower Suwannee River basin, Florida

Morphometric characteristics of ∼25 000 karstic depressions suggest that the last phase of the post-Miocene karstic evolution within the lower Suwannee River basin of Florida has been controlled by the lower sea-level stands of the Pleistocene and the formation of the Suwannee River. During the Pleistocene, as interglacial seas retreated, marine terraces formed by sequential sea-level lowstands and the time period of subaerial exposure diminished toward the sea. Consequently, geomorphologically younger karst landforms formed as the elevation of marine terraces decreased. The evolutionary geomorphological development of this heavily karstified region produced more frequent and/or larger and more complex depressions at higher elevations. A geographic information system analysis of morphometric and spatial distribution parameters of the karstic depressions within the lower Suwannee River basin reveals that the Florida karst is represented by broad, shallow depressions with an average density of 6.07/km 2 and an average pitting index of 14.5. Morphometric and spatial distribution parameters of karstic depressions show a great variation within the lower Suwannee River area and thus preclude a simple morphoclimatic classification of karst landforms. The Tertiary carbonate rocks of the subtropical Florida karst have relatively less joint frequency and significant primary porosity, and do not produce the extreme karst landforms observed in the massive limestones of the tropics.

Variability of Site Response in Seattle, Washington

Ground motion from local earthquakes and the SHIPS (Seismic Hazards Investigation in Puget Sound) experiment is used to estimate site amplification factors in Seattle. Earthquake and SHIPS records are analyzed by two methods: (1) spectral ratios relative to a nearby site on Tertiary sandstone, and (2) a source/site spectral inversion technique. Our results show site amplifications between 3 and 4 below 5 Hz for West Seattle relative to Tertiary rock. These values are approximately 30% lower than amplification in the Duwamish Valley on artificial fill, but significantly higher than the calculated range of 2 to 2.5 below 5 Hz for the till-covered hills east of downtown Seattle. Although spectral amplitudes are only 30% higher in the Duwamish Valley compared to West Seattle, the duration of long-period ground motion is significantly greater on the artificial fill sites. Using a three-dimensional displacement response spectrum measure that includes the effects of ground-motion duration, values in the Duwamish Valley are 2 to 3 times greater than West Seattle. These calculations and estimates of site response as a function of receiver azimuth point out the importance of trapped surface-wave energy within the shallow, low-velocity, sedimentary layers of the Duwamish Valley. One-dimensional velocity models yield spectral amplification factors close to the observations for till sites east of downtown Seattle and the Duwamish Valley, but underpredict amplifications by a factor of 2 in West Seattle. A two-dimensional finite-difference model does equally well for the till sites and the Duwamish Valley and also yields duration estimates consistent with the observations for the Duwamish Valley. The two-dimensional model, however, still underpredicts amplification in West Seattle by up to a factor of 2. This discrepancy is attributed to 3D effects, including basin-edge–induced surface waves and basin-geometry–focusing effects, caused by the proximity of the Seattle thrust fault and the sediment-filled Seattle basin.

Interplay of intraplate tectonics and surface processes in the Sierra de Guadarrama (central Spain) assessed by apatite fission track analysis

Apatite fission track analysis is used as a tectonic tool to unravel the evolution of the Sierra de Guadarrama, an mountain range in central Spain, and the far-field effects of the Alpine plate tectonics, expressed by reactivation of NE-SW trending lineaments in the Hercynian basement. 18 basement samples were analysed, and 4 sediments of Mesozoic and Tertiary age. Thermal histories were modelled for most samples and conversion to resultant amounts of denudation and rock uplift was possible for the Tertiary history, because of constraints on the paleo-topography and -elevation in Upper Cretaceous to Paleocene times. Accelerated cooling (up to 100 °C in 5 Ma) occurred around 100 Ma in the entire Sierra de Guadarrama. In the northern part, this cooling was preceded by reheating of Lower Triassic sediments up to 110 °C, suggesting sedimentation of about 3 km of, now eroded, Upper Triassic to Jurassic. The period of greatest erosion occurred in the Pliocene and Quaternary and affected almost the entire Sierra de Guadarrama. It was preceded by a Middle-Miocene cooling event that correlates with the beginning of the neo-tectonic setting of central Spain. The greatest Tertiary rock uplift occurred in the central part of the Sierra de Guadarrama: 5.9 ± 11.6 km. The Pliocene to recent event constitutes most of the Tertiary denudation. It is accommodated by active NE-SW trending reverse faults, and attended by about 3.2 km of denudation. These data fit as far-field effects in the plate tectonic setting of ongoing NW-SE oriented convergence between the European and African plate.